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21 /*
22 * Copyright 2010 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 * Copyright 2018 Joyent, Inc.
25 * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
26 */
27
28 /*
29 * MAC data path
30 *
31 * The MAC data path is concerned with the flow of traffic from mac clients --
32 * DLS, IP, etc. -- to various GLDv3 device drivers -- e1000g, vnic, aggr,
33 * ixgbe, etc. -- and from the GLDv3 device drivers back to clients.
34 *
35 * -----------
36 * Terminology
37 * -----------
38 *
39 * MAC uses a lot of different, but related terms that are associated with the
40 * design and structure of the data path. Before we cover other aspects, first
41 * let's review the terminology that MAC uses.
42 *
43 * MAC
44 *
45 * This driver. It interfaces with device drivers and provides abstractions
46 * that the rest of the system consumes. All data links -- things managed
47 * with dladm(8), are accessed through MAC.
48 *
49 * GLDv3 DEVICE DRIVER
50 *
51 * A GLDv3 device driver refers to a driver, both for pseudo-devices and
52 * real devices, which implement the GLDv3 driver API. Common examples of
53 * these are igb and ixgbe, which are drivers for various Intel networking
54 * cards. These devices may or may not have various features, such as
55 * hardware rings and checksum offloading. For MAC, a GLDv3 device is the
56 * final point for the transmission of a packet and the starting point for
57 * the receipt of a packet.
58 *
59 * FLOWS
60 *
61 * At a high level, a flow refers to a series of packets that are related.
62 * Often times the term is used in the context of TCP to indicate a unique
63 * TCP connection and the traffic over it. However, a flow can exist at
64 * other levels of the system as well. MAC has a notion of a default flow
65 * which is used for all unicast traffic addressed to the address of a MAC
66 * device. For example, when a VNIC is created, a default flow is created
67 * for the VNIC's MAC address. In addition, flows are created for broadcast
68 * groups and a user may create a flow with flowadm(8).
69 *
70 * CLASSIFICATION
71 *
72 * Classification refers to the notion of identifying an incoming frame
73 * based on its destination address and optionally its source addresses and
74 * doing different processing based on that information. Classification can
75 * be done in both hardware and software. In general, we usually only
76 * classify based on the layer two destination, eg. for Ethernet, the
77 * destination MAC address.
78 *
79 * The system also will do classification based on layer three and layer
80 * four properties. This is used to support things like flowadm(8), which
81 * allows setting QoS and other properties on a per-flow basis.
82 *
83 * RING
84 *
85 * Conceptually, a ring represents a series of framed messages, often in a
86 * contiguous chunk of memory that acts as a circular buffer. Rings come in
87 * a couple of forms. Generally they are either a hardware construct (hw
88 * ring) or they are a software construct (sw ring) maintained by MAC.
89 *
90 * HW RING
91 *
92 * A hardware ring is a set of resources provided by a GLDv3 device driver
93 * (even if it is a pseudo-device). A hardware ring comes in two different
94 * forms: receive (rx) rings and transmit (tx) rings. An rx hw ring is
95 * something that has a unique DMA (direct memory access) region and
96 * generally supports some form of classification (though it isn't always
97 * used), as well as a means of generating an interrupt specific to that
98 * ring. For example, the device may generate a specific MSI-X for a PCI
99 * express device. A tx ring is similar, except that it is dedicated to
100 * transmission. It may also be a vector for enabling features such as VLAN
101 * tagging and large transmit offloading. It usually has its own dedicated
102 * interrupts for transmit being completed.
103 *
104 * SW RING
105 *
106 * A software ring is a construction of MAC. It represents the same thing
107 * that a hardware ring generally does, a collection of frames. However,
108 * instead of being in a contiguous ring of memory, they're instead linked
109 * by using the mblk_t's b_next pointer. Each frame may itself be multiple
110 * mblk_t's linked together by the b_cont pointer. A software ring always
111 * represents a collection of classified packets; however, it varies as to
112 * whether it uses only layer two information, or a combination of that and
113 * additional layer three and layer four data.
114 *
115 * FANOUT
116 *
117 * Fanout is the idea of spreading out the load of processing frames based
118 * on the source and destination information contained in the layer two,
119 * three, and four headers, such that the data can then be processed in
120 * parallel using multiple hardware threads.
121 *
122 * A fanout algorithm hashes the headers and uses that to place different
123 * flows into a bucket. The most important thing is that packets that are
124 * in the same flow end up in the same bucket. If they do not, performance
125 * can be adversely affected. Consider the case of TCP. TCP severely
126 * penalizes a connection if the data arrives out of order. If a given flow
127 * is processed on different CPUs, then the data will appear out of order,
128 * hence the invariant that fanout always hash a given flow to the same
129 * bucket and thus get processed on the same CPU.
130 *
131 * RECEIVE SIDE SCALING (RSS)
132 *
133 *
134 * Receive side scaling is a term that isn't common in illumos, but is used
135 * by vendors and was popularized by Microsoft. It refers to the idea of
136 * spreading the incoming receive load out across multiple interrupts which
137 * can be directed to different CPUs. This allows a device to leverage
138 * hardware rings even when it doesn't support hardware classification. The
139 * hardware uses an algorithm to perform fanout that ensures the flow
140 * invariant is maintained.
141 *
142 * SOFT RING SET
143 *
144 * A soft ring set, commonly abbreviated SRS, is a collection of rings and
145 * is used for both transmitting and receiving. It is maintained in the
146 * structure mac_soft_ring_set_t. A soft ring set is usually associated
147 * with flows, and coordinates both the use of hardware and software rings.
148 * Because the use of hardware rings can change as devices such as VNICs
149 * come and go, we always ensure that the set has software classification
150 * rules that correspond to the hardware classification rules from rings.
151 *
152 * Soft ring sets are also used for the enforcement of various QoS
153 * properties. For example, if a bandwidth limit has been placed on a
154 * specific flow or device, then that will be enforced by the soft ring
155 * set.
156 *
157 * SERVICE ATTACHMENT POINT (SAP)
158 *
159 * The service attachment point is a DLPI (Data Link Provider Interface)
160 * concept; however, it comes up quite often in MAC. Most MAC devices speak
161 * a protocol that has some notion of different channels or message type
162 * identifiers. For example, Ethernet defines an EtherType which is a part
163 * of the Ethernet header and defines the particular protocol of the data
164 * payload. If the EtherType is set to 0x0800, then it defines that the
165 * contents of that Ethernet frame is IPv4 traffic. For Ethernet, the
166 * EtherType is the SAP.
167 *
168 * In DLPI, a given consumer attaches to a specific SAP. In illumos, the ip
169 * and arp drivers attach to the EtherTypes for IPv4, IPv6, and ARP. Using
170 * libdlpi(3LIB) user software can attach to arbitrary SAPs. With the
171 * exception of 802.1Q VLAN tagged traffic, MAC itself does not directly
172 * consume the SAP; however, it uses that information as part of hashing
173 * and it may be used as part of the construction of flows.
174 *
175 * PRIMARY MAC CLIENT
176 *
177 * The primary mac client refers to a mac client whose unicast address
178 * matches the address of the device itself. For example, if the system has
179 * instance of the e1000g driver such as e1000g0, e1000g1, etc., the
180 * primary mac client is the one named after the device itself. VNICs that
181 * are created on top of such devices are not the primary client.
182 *
183 * TRANSMIT DESCRIPTORS
184 *
185 * Transmit descriptors are a resource that most GLDv3 device drivers have.
186 * Generally, a GLDv3 device driver takes a frame that's meant to be output
187 * and puts a copy of it into a region of memory. Each region of memory
188 * usually has an associated descriptor that the device uses to manage
189 * properties of the frames. Devices have a limited number of such
190 * descriptors. They get reclaimed once the device finishes putting the
191 * frame on the wire.
192 *
193 * If the driver runs out of transmit descriptors, for example, the OS is
194 * generating more frames than it can put on the wire, then it will return
195 * them back to the MAC layer.
196 *
197 * ---------------------------------
198 * Rings, Classification, and Fanout
199 * ---------------------------------
200 *
201 * The heart of MAC is made up of rings, and not those that Elven-kings wear.
202 * When receiving a packet, MAC breaks the work into two different, though
203 * interrelated phases. The first phase is generally classification and then the
204 * second phase is generally fanout. When a frame comes in from a GLDv3 Device,
205 * MAC needs to determine where that frame should be delivered. If it's a
206 * unicast frame (say a normal TCP/IP packet), then it will be delivered to a
207 * single MAC client; however, if it's a broadcast or multicast frame, then MAC
208 * may need to deliver it to multiple MAC clients.
209 *
210 * On transmit, classification isn't quite as important, but may still be used.
211 * Unlike with the receive path, the classification is not used to determine
212 * devices that should transmit something, but rather is used for special
213 * properties of a flow, eg. bandwidth limits for a given IP address, device, or
214 * connection.
215 *
216 * MAC employs a software classifier and leverages hardware classification as
217 * well. The software classifier can leverage the full layer two information,
218 * source, destination, VLAN, and SAP. If the SAP indicates that IP traffic is
219 * being sent, it can classify based on the IP header, and finally, it also
220 * knows how to classify based on the local and remote ports of TCP, UDP, and
221 * SCTP.
222 *
223 * Hardware classifiers vary in capability. Generally all hardware classifiers
224 * provide the capability to classify based on the destination MAC address. Some
225 * hardware has additional filters built in for performing more in-depth
226 * classification; however, it often has much more limited resources for these
227 * activities as compared to the layer two destination address classification.
228 *
229 * The modus operandi in MAC is to always ensure that we have software-based
230 * capabilities and rules in place and then to supplement that with hardware
231 * resources when available. In general, simple layer two classification is
232 * sufficient and nothing else is used, unless a specific flow is created with
233 * tools such as flowadm(8) or bandwidth limits are set on a device with
234 * dladm(8).
235 *
236 * RINGS AND GROUPS
237 *
238 * To get into how rings and classification play together, it's first important
239 * to understand how hardware devices commonly associate rings and allow them to
240 * be programmed. Recall that a hardware ring should be thought of as a DMA
241 * buffer and an interrupt resource. Rings are then collected into groups. A
242 * group itself has a series of classification rules. One or more MAC addresses
243 * are assigned to a group.
244 *
245 * Hardware devices vary in terms of what capabilities they provide. Sometimes
246 * they allow for a dynamic assignment of rings to a group and sometimes they
247 * have a static assignment of rings to a group. For example, the ixgbe driver
248 * has a static assignment of rings to groups such that every group has exactly
249 * one ring and the number of groups is equal to the number of rings.
250 *
251 * Classification and receive side scaling both come into play with how a device
252 * advertises itself to MAC and how MAC uses it. If a device supports layer two
253 * classification of frames, then MAC will assign MAC addresses to a group as a
254 * form of primary classification. If a single MAC address is assigned to a
255 * group, a common case, then MAC will consider packets that come in from rings
256 * on that group to be fully classified and will not need to do any software
257 * classification unless a specific flow has been created.
258 *
259 * If a device supports receive side scaling, then it may advertise or support
260 * groups with multiple rings. In those cases, then receive side scaling will
261 * come into play and MAC will use that as a means of fanning out received
262 * frames across multiple CPUs. This can also be combined with groups that
263 * support layer two classification.
264 *
265 * If a device supports dynamic assignments of rings to groups, then MAC will
266 * change around the way that rings are assigned to various groups as devices
267 * come and go from the system. For example, when a VNIC is created, a new flow
268 * will be created for the VNIC's MAC address. If a hardware ring is available,
269 * MAC may opt to reassign it from one group to another.
270 *
271 * ASSIGNMENT OF HARDWARE RINGS
272 *
273 * This is a bit of a complicated subject that varies depending on the device,
274 * the use of aggregations, the special nature of the primary mac client. This
275 * section deserves being fleshed out.
276 *
277 * FANOUT
278 *
279 * illumos uses fanout to help spread out the incoming processing load of chains
280 * of frames away from a single CPU. If a device supports receive side scaling,
281 * then that provides an initial form of fanout; however, what we're concerned
282 * with all happens after the context of a given set of frames being classified
283 * to a soft ring set.
284 *
285 * After frames reach a soft ring set and account for any potential bandwidth
286 * related accounting, they may be fanned out based on one of the following
287 * three modes:
288 *
289 * o No Fanout
290 * o Protocol level fanout
291 * o Full software ring protocol fanout
292 *
293 * MAC makes the determination as to which of these modes a given soft ring set
294 * obtains based on parameters such as whether or not it's the primary mac
295 * client, whether it's on a 10 GbE or faster device, user controlled dladm(8)
296 * properties, and the nature of the hardware and the resources that it has.
297 *
298 * When there is no fanout, MAC does not create any soft rings for a device and
299 * the device has frames delivered directly to the MAC client.
300 *
301 * Otherwise, all fanout is performed by software. MAC divides incoming frames
302 * into one of three buckets -- IPv4 TCP traffic, IPv4 UDP traffic, and
303 * everything else. Regardless of the type of fanout, these three categories
304 * or buckets are always used.
305 *
306 * The difference between protocol level fanout and full software ring protocol
307 * fanout is the number of software rings that end up getting created. The
308 * system always uses the same number of software rings per protocol bucket. So
309 * in the first case when we're just doing protocol level fanout, we just create
310 * one software ring each for IPv4 TCP traffic, IPv4 UDP traffic, and everything
311 * else.
312 *
313 * In the case where we do full software ring protocol fanout, we generally use
314 * mac_compute_soft_ring_count() to determine the number of rings. There are
315 * other combinations of properties and devices that may send us down other
316 * paths, but this is a common starting point. If it's a non-bandwidth enforced
317 * device and we're on at least a 10 GbE link, then we'll use eight soft rings
318 * per protocol bucket as a starting point. See mac_compute_soft_ring_count()
319 * for more information on the total number.
320 *
321 * For each of these rings, we create a mac_soft_ring_t and an associated worker
322 * thread. Particularly when doing full software ring protocol fanout, we bind
323 * each of the worker threads to individual CPUs.
324 *
325 * The other advantage of these software rings is that it allows upper layers to
326 * optionally poll on them. For example, TCP can leverage an squeue to poll on
327 * the software ring, see squeue.c for more information.
328 *
329 * DLS BYPASS
330 *
331 * DLS is the data link services module. It interfaces with DLPI, which is the
332 * primary way that other parts of the system such as IP interface with the MAC
333 * layer. While DLS is traditionally a STREAMS-based interface, it allows for
334 * certain modules such as IP to negotiate various more modern interfaces to be
335 * used, which are useful for higher performance and allow it to use direct
336 * function calls to DLS instead of using STREAMS.
337 *
338 * When we have IPv4 TCP or UDP software rings, then traffic on those rings is
339 * eligible for what we call the dls bypass. In those cases, rather than going
340 * out mac_rx_deliver() to DLS, DLS instead registers them to go directly via
341 * the direct callback registered with DLS, generally ip_input().
342 *
343 * HARDWARE RING POLLING
344 *
345 * GLDv3 devices with hardware rings generally deliver chains of messages
346 * (mblk_t chain) during the context of a single interrupt. However, interrupts
347 * are not the only way that these devices may be used. As part of implementing
348 * ring support, a GLDv3 device driver must have a way to disable the generation
349 * of that interrupt and allow for the operating system to poll on that ring.
350 *
351 * To implement this, every soft ring set has a worker thread and a polling
352 * thread. If a sufficient packet rate comes into the system, MAC will 'blank'
353 * (disable) interrupts on that specific ring and the polling thread will start
354 * consuming packets from the hardware device and deliver them to the soft ring
355 * set, where the worker thread will take over.
356 *
357 * Once the rate of packet intake drops down below a certain threshold, then
358 * polling on the hardware ring will be quiesced and interrupts will be
359 * re-enabled for the given ring. This effectively allows the system to shift
360 * how it handles a ring based on its load. At high packet rates, polling on the
361 * device as opposed to relying on interrupts can actually reduce overall system
362 * load due to the minimization of interrupt activity.
363 *
364 * Note the importance of each ring having its own interrupt source. The whole
365 * idea here is that we do not disable interrupts on the device as a whole, but
366 * rather each ring can be independently toggled.
367 *
368 * USE OF WORKER THREADS
369 *
370 * Both the soft ring set and individual soft rings have a worker thread
371 * associated with them that may be bound to a specific CPU in the system. Any
372 * such assignment will get reassessed as part of dynamic reconfiguration events
373 * in the system such as the onlining and offlining of CPUs and the creation of
374 * CPU partitions.
375 *
376 * In many cases, while in an interrupt, we try to deliver a frame all the way
377 * through the stack in the context of the interrupt itself. However, if the
378 * amount of queued frames has exceeded a threshold, then we instead defer to
379 * the worker thread to do this work and signal it. This is particularly useful
380 * when you have the soft ring set delivering frames into multiple software
381 * rings. If it was only delivering frames into a single software ring then
382 * there'd be no need to have another thread take over. However, if it's
383 * delivering chains of frames to multiple rings, then it's worthwhile to have
384 * the worker for the software ring take over so that the different software
385 * rings can be processed in parallel.
386 *
387 * In a similar fashion to the hardware polling thread, if we don't have a
388 * backlog or there's nothing to do, then the worker thread will go back to
389 * sleep and frames can be delivered all the way from an interrupt. This
390 * behavior is useful as it's designed to minimize latency and the default
391 * disposition of MAC is to optimize for latency.
392 *
393 * MAINTAINING CHAINS
394 *
395 * Another useful idea that MAC uses is to try and maintain frames in chains for
396 * as long as possible. The idea is that all of MAC can handle chains of frames
397 * structured as a series of mblk_t structures linked with the b_next pointer.
398 * When performing software classification and software fanout, MAC does not
399 * simply determine the destination and send the frame along. Instead, in the
400 * case of classification, it tries to maintain a chain for as long as possible
401 * before passing it along and performing additional processing.
402 *
403 * In the case of fanout, MAC first determines what the target software ring is
404 * for every frame in the original chain and constructs a new chain for each
405 * target. MAC then delivers the new chain to each software ring in succession.
406 *
407 * The whole rationale for doing this is that we want to try and maintain the
408 * pipe as much as possible and deliver as many frames through the stack at once
409 * that we can, rather than just pushing a single frame through. This can often
410 * help bring down latency and allows MAC to get a better sense of the overall
411 * activity in the system and properly engage worker threads.
412 *
413 * --------------------
414 * Bandwidth Management
415 * --------------------
416 *
417 * Bandwidth management is something that's built into the soft ring set itself.
418 * When bandwidth limits are placed on a flow, a corresponding soft ring set is
419 * toggled into bandwidth mode. This changes how we transmit and receive the
420 * frames in question.
421 *
422 * Bandwidth management is done on a per-tick basis. We translate the user's
423 * requested bandwidth from a quantity per-second into a quantity per-tick. MAC
424 * cannot process a frame across more than one tick, thus it sets a lower bound
425 * for the bandwidth cap to be a single MTU. This also means that when
426 * hires ticks are enabled (hz is set to 1000), that the minimum amount of
427 * bandwidth is higher, because the number of ticks has increased and MAC has to
428 * go from accepting 100 packets / sec to 1000 / sec.
429 *
430 * The bandwidth counter is reset by either the soft ring set's worker thread or
431 * a thread that is doing an inline transmit or receive if they discover that
432 * the current tick is in the future from the recorded tick.
433 *
434 * Whenever we're receiving or transmitting data, we end up leaving most of the
435 * work to the soft ring set's worker thread. This forces data inserted into the
436 * soft ring set to be effectively serialized and allows us to exhume bandwidth
437 * at a reasonable rate. If there is nothing in the soft ring set at the moment
438 * and the set has available bandwidth, then it may processed inline.
439 * Otherwise, the worker is responsible for taking care of the soft ring set.
440 *
441 * ---------------------
442 * The Receive Data Path
443 * ---------------------
444 *
445 * The following series of ASCII art images breaks apart the way that a frame
446 * comes in and is processed in MAC.
447 *
448 * Part 1 -- Initial frame receipt, SRS classification
449 *
450 * Here, a frame is received by a GLDv3 driver, generally in the context of an
451 * interrupt, and it ends up in mac_rx_common(). A driver calls either mac_rx or
452 * mac_rx_ring, depending on whether or not it supports rings and can identify
453 * the interrupt as having come from a specific ring. Here we determine whether
454 * or not it's fully classified and perform software classification as
455 * appropriate. From here, everything always ends up going to either entry [A]
456 * or entry [B] based on whether or not they have subflow processing needed. We
457 * leave via fanout or delivery.
458 *
459 * +===========+
460 * v hardware v
461 * v interrupt v
462 * +===========+
463 * |
464 * * . . appropriate
465 * | upcall made
466 * | by GLDv3 driver . . always
467 * | .
468 * +--------+ | +----------+ . +---------------+
469 * | GLDv3 | +---->| mac_rx |-----*--->| mac_rx_common |
470 * | Driver |-->--+ +----------+ +---------------+
471 * +--------+ | ^ |
472 * | | ^ v
473 * ^ | * . . always +----------------------+
474 * | | | | mac_promisc_dispatch |
475 * | | +-------------+ +----------------------+
476 * | +--->| mac_rx_ring | |
477 * | +-------------+ * . . hw classified
478 * | v or single flow?
479 * | |
480 * | +--------++--------------+
481 * | | | * hw class,
482 * | | * hw classified | subflows
483 * | no hw class and . * | or single | exist
484 * | subflows | | flow |
485 * | | v v
486 * | | +-----------+ +-----------+
487 * | | | goto | | goto |
488 * | | | entry [A] | | entry [B] |
489 * | | +-----------+ +-----------+
490 * | v ^
491 * | +-------------+ |
492 * | | mac_rx_flow | * SRS and flow found,
493 * | +-------------+ | call flow cb
494 * | | +------+
495 * | v |
496 * v +==========+ +-----------------+
497 * | v For each v--->| mac_rx_classify |
498 * +----------+ v mblk_t v +-----------------+
499 * | srs | +==========+
500 * | pollling |
501 * | thread |->------------------------------------------+
502 * +----------+ |
503 * v . inline
504 * +--------------------+ +----------+ +---------+ .
505 * [A]---->| mac_rx_srs_process |-->| check bw |-->| enqueue |--*---------+
506 * +--------------------+ | limits | | frames | |
507 * ^ +----------+ | to SRS | |
508 * | +---------+ |
509 * | send chain +--------+ | |
510 * * when clasified | signal | * BW limits, |
511 * | flow changes | srs |<---+ loopback, |
512 * | | worker | stack too |
513 * | +--------+ deep |
514 * +-----------------+ +--------+ |
515 * | mac_flow_lookup | | srs | +---------------------+ |
516 * +-----------------+ | worker |---->| mac_rx_srs_drain |<---+
517 * ^ | thread | | mac_rx_srs_drain_bw |
518 * | +--------+ +---------------------+
519 * | |
520 * +----------------------------+ * software rings
521 * [B]-->| mac_rx_srs_subflow_process | | for fanout?
522 * +----------------------------+ |
523 * +----------+-----------+
524 * | |
525 * v v
526 * +--------+ +--------+
527 * | goto | | goto |
528 * | Part 2 | | Part 3 |
529 * +--------+ +--------+
530 *
531 * Part 2 -- Fanout
532 *
533 * This part is concerned with using software fanout to assign frames to
534 * software rings and then deliver them to MAC clients or allow those rings to
535 * be polled upon. While there are two different primary fanout entry points,
536 * mac_rx_fanout and mac_rx_proto_fanout, they behave in similar ways, and aside
537 * from some of the individual hashing techniques used, most of the general
538 * flow is the same.
539 *
540 * +--------+ +-------------------+
541 * | From |---+--------->| mac_rx_srs_fanout |----+
542 * | Part 1 | | +-------------------+ | +=================+
543 * +--------+ | | v for each mblk_t v
544 * * . . protocol only +--->v assign to new v
545 * | fanout | v chain based on v
546 * | | v hash % nrings v
547 * | +-------------------------+ | +=================+
548 * +--->| mac_rx_srs_proto_fanout |----+ |
549 * +-------------------------+ |
550 * v
551 * +------------+ +--------------------------+ +================+
552 * | enqueue in |<---| mac_rx_soft_ring_process |<------v for each chain v
553 * | soft ring | +--------------------------+ +================+
554 * +------------+
555 * | +-----------+
556 * * soft ring set | soft ring |
557 * | empty and no | worker |
558 * | worker? | thread |
559 * | +-----------+
560 * +------*----------------+ |
561 * | . | v
562 * No . * . Yes | +------------------------+
563 * | +----<--| mac_rx_soft_ring_drain |
564 * | | +------------------------+
565 * v |
566 * +-----------+ v
567 * | signal | +---------------+
568 * | soft ring | | Deliver chain |
569 * | worker | | goto Part 3 |
570 * +-----------+ +---------------+
571 *
572 *
573 * Part 3 -- Packet Delivery
574 *
575 * Here, we go through and deliver the mblk_t chain directly to a given
576 * processing function. In a lot of cases this is mac_rx_deliver(). In the case
577 * of DLS bypass being used, then instead we end up going ahead and deliver it
578 * to the direct callback registered with DLS, generally ip_input.
579 *
580 *
581 * +---------+ +----------------+ +------------------+
582 * | From |---+------->| mac_rx_deliver |--->| Off to DLS, or |
583 * | Parts 1 | | +----------------+ | other MAC client |
584 * | and 2 | * DLS bypass +------------------+
585 * +---------+ | enabled +----------+ +-------------+
586 * +---------->| ip_input |--->| To IP |
587 * +----------+ | and beyond! |
588 * +-------------+
589 *
590 * ----------------------
591 * The Transmit Data Path
592 * ----------------------
593 *
594 * Before we go into the images, it's worth talking about a problem that is a
595 * bit different from the receive data path. GLDv3 device drivers have a finite
596 * amount of transmit descriptors. When they run out, they return unused frames
597 * back to MAC. MAC, at this point has several options about what it will do,
598 * which vary based upon the settings that the client uses.
599 *
600 * When a device runs out of descriptors, the next thing that MAC does is
601 * enqueue them off of the soft ring set or a software ring, depending on the
602 * configuration of the soft ring set. MAC will enqueue up to a high watermark
603 * of mblk_t chains, at which point it will indicate flow control back to the
604 * client. Once this condition is reached, any mblk_t chains that were not
605 * enqueued will be returned to the caller and they will have to decide what to
606 * do with them. There are various flags that control this behavior that a
607 * client may pass, which are discussed below.
608 *
609 * When this condition is hit, MAC also returns a cookie to the client in
610 * addition to unconsumed frames. Clients can poll on that cookie and register a
611 * callback with MAC to be notified when they are no longer subject to flow
612 * control, at which point they may continue to call mac_tx(). This flow control
613 * actually manages to work itself all the way up the stack, back through dls,
614 * to ip, through the various protocols, and to sockfs.
615 *
616 * While the behavior described above is the default, this behavior can be
617 * modified. There are two alternate modes, described below, which are
618 * controlled with flags.
619 *
620 * DROP MODE
621 *
622 * This mode is controlled by having the client pass the MAC_DROP_ON_NO_DESC
623 * flag. When this is passed, if a device driver runs out of transmit
624 * descriptors, then the MAC layer will drop any unsent traffic. The client in
625 * this case will never have any frames returned to it.
626 *
627 * DON'T ENQUEUE
628 *
629 * This mode is controlled by having the client pass the MAC_TX_NO_ENQUEUE flag.
630 * If the MAC_DROP_ON_NO_DESC flag is also passed, it takes precedence. In this
631 * mode, when we hit a case where a driver runs out of transmit descriptors,
632 * then instead of enqueuing packets in a soft ring set or software ring, we
633 * instead return the mblk_t chain back to the caller and immediately put the
634 * soft ring set into flow control mode.
635 *
636 * The following series of ASCII art images describe the transmit data path that
637 * MAC clients enter into based on calling into mac_tx(). A soft ring set has a
638 * transmission function associated with it. There are seven possible
639 * transmission modes, some of which share function entry points. The one that a
640 * soft ring set gets depends on properties such as whether there are
641 * transmission rings for fanout, whether the device involves aggregations,
642 * whether any bandwidth limits exist, etc.
643 *
644 *
645 * Part 1 -- Initial checks
646 *
647 * * . called by
648 * | MAC clients
649 * v . . No
650 * +--------+ +-----------+ . +-------------------+ +====================+
651 * | mac_tx |->| device |-*-->| mac_protect_check |->v Is this the simple v
652 * +--------+ | quiesced? | +-------------------+ v case? See [1] v
653 * +-----------+ | +====================+
654 * * . Yes * failed |
655 * v | frames |
656 * +--------------+ | +-------+---------+
657 * | freemsgchain |<---------+ Yes . * No . *
658 * +--------------+ v v
659 * +-----------+ +--------+
660 * | goto | | goto |
661 * | Part 2 | | SRS TX |
662 * | Entry [A] | | func |
663 * +-----------+ +--------+
664 * | |
665 * | v
666 * | +--------+
667 * +---------->| return |
668 * | cookie |
669 * +--------+
670 *
671 * [1] The simple case refers to the SRS being configured with the
672 * SRS_TX_DEFAULT transmission mode, having a single mblk_t (not a chain), their
673 * being only a single active client, and not having a backlog in the srs.
674 *
675 *
676 * Part 2 -- The SRS transmission functions
677 *
678 * This part is a bit more complicated. The different transmission paths often
679 * leverage one another. In this case, we'll draw out the more common ones
680 * before the parts that depend upon them. Here, we're going to start with the
681 * workings of mac_tx_send() a common function that most of the others end up
682 * calling.
683 *
684 * +-------------+
685 * | mac_tx_send |
686 * +-------------+
687 * |
688 * v
689 * +=============+ +==============+
690 * v more than v--->v check v
691 * v one client? v v VLAN and add v
692 * +=============+ v VLAN tags v
693 * | +==============+
694 * | |
695 * +------------------+
696 * |
697 * | [A]
698 * v |
699 * +============+ . No v
700 * v more than v . +==========+ +--------------------------+
701 * v one active v-*---->v for each v---->| mac_promisc_dispatch_one |---+
702 * v client? v v mblk_t v +--------------------------+ |
703 * +============+ +==========+ ^ |
704 * | | +==========+ |
705 * * . Yes | v hardware v<-------+
706 * v +------------+ v rings? v
707 * +==========+ | +==========+
708 * v for each v No . . . * |
709 * v mblk_t v specific | |
710 * +==========+ flow | +-----+-----+
711 * | | | |
712 * v | v v
713 * +-----------------+ | +-------+ +---------+
714 * | mac_tx_classify |------------+ | GLDv3 | | GLDv3 |
715 * +-----------------+ |TX func| | ring tx |
716 * | +-------+ | func |
717 * * Specific flow, generally | +---------+
718 * | bcast, mcast, loopback | |
719 * v +-----+-----+
720 * +==========+ +---------+ |
721 * v valid L2 v--*--->| freemsg | v
722 * v header v . No +---------+ +-------------------+
723 * +==========+ | return unconsumed |
724 * * . Yes | frames to the |
725 * v | caller |
726 * +===========+ +-------------------+
727 * v braodcast v +----------------+ ^
728 * v flow? v--*-->| mac_bcast_send |------------------+
729 * +===========+ . +----------------+ |
730 * | . . Yes |
731 * No . * v
732 * | +---------------------+ +---------------+ +----------+
733 * +->|mac_promisc_dispatch |->| mac_fix_cksum |->| flow |
734 * +---------------------+ +---------------+ | callback |
735 * +----------+
736 *
737 *
738 * In addition, many but not all of the routines, all rely on
739 * mac_tx_softring_process as an entry point.
740 *
741 *
742 * . No . No
743 * +--------------------------+ +========+ . +===========+ . +-------------+
744 * | mac_tx_soft_ring_process |-->v worker v-*->v out of tx v-*->| goto |
745 * +--------------------------+ v only? v v descr.? v | mac_tx_send |
746 * +========+ +===========+ +-------------+
747 * Yes . * * . Yes |
748 * . No v | v
749 * v=========+ . +===========+ . Yes | Yes . +==========+
750 * v apppend v<--*----------v out of tx v-*-------+---------*--v returned v
751 * v mblk_t v v descr.? v | v frames? v
752 * v chain v +===========+ | +==========+
753 * +=========+ | *. No
754 * | | v
755 * v v +------------+
756 * +===================+ +----------------------+ | done |
757 * v worker scheduled? v | mac_tx_sring_enqueue | | processing |
758 * v Out of tx descr? v +----------------------+ +------------+
759 * +===================+ |
760 * | | . Yes v
761 * * Yes * No . +============+
762 * | v +-*---------v drop on no v
763 * | +========+ v v TX desc? v
764 * | v wake v +----------+ +============+
765 * | v worker v | mac_pkt_ | * . No
766 * | +========+ | drop | | . Yes . No
767 * | | +----------+ v . .
768 * | | v ^ +===============+ . +========+ .
769 * +--+--------+---------+ | v Don't enqueue v-*->v ring v-*----+
770 * | | v Set? v v empty? v |
771 * | +---------------+ +===============+ +========+ |
772 * | | | | |
773 * | | +-------------------+ | |
774 * | *. Yes | +---------+ |
775 * | | v v v
776 * | | +===========+ +========+ +--------------+
777 * | +<-v At hiwat? v v append v | return |
778 * | +===========+ v mblk_t v | mblk_t chain |
779 * | * No v chain v | and flow |
780 * | v +========+ | control |
781 * | +=========+ | | cookie |
782 * | v append v v +--------------+
783 * | v mblk_t v +========+
784 * | v chain v v wake v +------------+
785 * | +=========+ v worker v-->| done |
786 * | | +========+ | processing |
787 * | v .. Yes +------------+
788 * | +=========+ . +========+
789 * | v first v--*-->v wake v
790 * | v append? v v worker v
791 * | +=========+ +========+
792 * | | |
793 * | No . * |
794 * | v |
795 * | +--------------+ |
796 * +------>| Return | |
797 * | flow control |<------------+
798 * | cookie |
799 * +--------------+
800 *
801 *
802 * The remaining images are all specific to each of the different transmission
803 * modes.
804 *
805 * SRS TX DEFAULT
806 *
807 * [ From Part 1 ]
808 * |
809 * v
810 * +-------------------------+
811 * | mac_tx_single_ring_mode |
812 * +-------------------------+
813 * |
814 * | . Yes
815 * v .
816 * +==========+ . +============+
817 * v SRS v-*->v Try to v---->---------------------+
818 * v backlog? v v enqueue in v |
819 * +==========+ v SRS v-->------+ * . . Queue too
820 * | +============+ * don't enqueue | deep or
821 * * . No ^ | | flag or at | drop flag
822 * | | v | hiwat, |
823 * v | | | return +---------+
824 * +-------------+ | | | cookie | freemsg |
825 * | goto |-*-----+ | | +---------+
826 * | mac_tx_send | . returned | | |
827 * +-------------+ mblk_t | | |
828 * | | | |
829 * | | | |
830 * * . . all mblk_t * queued, | |
831 * v consumed | may return | |
832 * +-------------+ | tx cookie | |
833 * | SRS TX func |<------------+------------+----------------+
834 * | completed |
835 * +-------------+
836 *
837 * SRS_TX_SERIALIZE
838 *
839 * +------------------------+
840 * | mac_tx_serializer_mode |
841 * +------------------------+
842 * |
843 * | . No
844 * v .
845 * +============+ . +============+ +-------------+ +============+
846 * v srs being v-*->v set SRS v--->| goto |-->v remove SRS v
847 * v processed? v v proc flags v | mac_tx_send | v proc flag v
848 * +============+ +============+ +-------------+ +============+
849 * | |
850 * * Yes |
851 * v . No v
852 * +--------------------+ . +==========+
853 * | mac_tx_srs_enqueue | +------------------------*-----<--v returned v
854 * +--------------------+ | v frames? v
855 * | | . Yes +==========+
856 * | | . |
857 * | | . +=========+ v
858 * v +-<-*-v queued v +--------------------+
859 * +-------------+ | v frames? v<----| mac_tx_srs_enqueue |
860 * | SRS TX func | | +=========+ +--------------------+
861 * | completed, |<------+ * . Yes
862 * | may return | | v
863 * | cookie | | +========+
864 * +-------------+ +-<---v wake v
865 * v worker v
866 * +========+
867 *
868 *
869 * SRS_TX_FANOUT
870 *
871 * . Yes
872 * +--------------------+ +=============+ . +--------------------------+
873 * | mac_tx_fanout_mode |--->v Have fanout v-*-->| goto |
874 * +--------------------+ v hint? v | mac_rx_soft_ring_process |
875 * +=============+ +--------------------------+
876 * * . No |
877 * v ^
878 * +===========+ |
879 * +--->v for each v +===============+
880 * | v mblk_t v v pick softring v
881 * same * +===========+ v from hash v
882 * hash | | +===============+
883 * | v |
884 * | +--------------+ |
885 * +---| mac_pkt_hash |--->*------------+
886 * +--------------+ . different
887 * hash or
888 * done proc.
889 * SRS_TX_AGGR chain
890 *
891 * +------------------+ +================================+
892 * | mac_tx_aggr_mode |--->v Use aggr capab function to v
893 * +------------------+ v find appropriate tx ring. v
894 * v Applies hash based on aggr v
895 * v policy, see mac_tx_aggr_mode() v
896 * +================================+
897 * |
898 * v
899 * +-------------------------------+
900 * | goto |
901 * | mac_rx_srs_soft_ring_process |
902 * +-------------------------------+
903 *
904 *
905 * SRS_TX_BW, SRS_TX_BW_FANOUT, SRS_TX_BW_AGGR
906 *
907 * Note, all three of these tx functions start from the same place --
908 * mac_tx_bw_mode().
909 *
910 * +----------------+
911 * | mac_tx_bw_mode |
912 * +----------------+
913 * |
914 * v . No . No . Yes
915 * +==============+ . +============+ . +=============+ . +=========+
916 * v Out of BW? v--*->v SRS empty? v--*->v reset BW v-*->v Bump BW v
917 * +==============+ +============+ v tick count? v v Usage v
918 * | | +=============+ +=========+
919 * | +---------+ | |
920 * | | +--------------------+ |
921 * | | | +----------------------+
922 * v | v v
923 * +===============+ | +==========+ +==========+ +------------------+
924 * v Don't enqueue v | v set bw v v Is aggr? v--*-->| goto |
925 * v flag set? v | v enforced v +==========+ . | mac_tx_aggr_mode |-+
926 * +===============+ | +==========+ | . +------------------+ |
927 * | Yes .* | | No . * . |
928 * | | | | | . Yes |
929 * * . No | | v | |
930 * | +---------+ | +========+ v +======+ |
931 * | | freemsg | | v append v +============+ . Yes v pick v |
932 * | +---------+ | v mblk_t v v Is fanout? v--*---->v ring v |
933 * | | | v chain v +============+ +======+ |
934 * +------+ | +========+ | | |
935 * v | | v v |
936 * +---------+ | v +-------------+ +--------------------+ |
937 * | return | | +========+ | goto | | goto | |
938 * | flow | | v wakeup v | mac_tx_send | | mac_tx_fanout_mode | |
939 * | control | | v worker v +-------------+ +--------------------+ |
940 * | cookie | | +========+ | | |
941 * +---------+ | | | +------+------+
942 * | v | |
943 * | +---------+ | v
944 * | | return | +============+ +------------+
945 * | | flow | v unconsumed v-------+ | done |
946 * | | control | v frames? v | | processing |
947 * | | cookie | +============+ | +------------+
948 * | +---------+ | |
949 * | Yes * |
950 * | | |
951 * | +===========+ |
952 * | v subtract v |
953 * | v unused bw v |
954 * | +===========+ |
955 * | | |
956 * | v |
957 * | +--------------------+ |
958 * +------------->| mac_tx_srs_enqueue | |
959 * +--------------------+ |
960 * | |
961 * | |
962 * +------------+ |
963 * | return fc | |
964 * | cookie and |<------+
965 * | mblk_t |
966 * +------------+
967 */
968
969 #include <sys/types.h>
970 #include <sys/callb.h>
971 #include <sys/pattr.h>
972 #include <sys/sdt.h>
973 #include <sys/strsubr.h>
974 #include <sys/strsun.h>
975 #include <sys/vlan.h>
976 #include <sys/stack.h>
977 #include <sys/archsystm.h>
978 #include <inet/ipsec_impl.h>
979 #include <inet/ip_impl.h>
980 #include <inet/sadb.h>
981 #include <inet/ipsecesp.h>
982 #include <inet/ipsecah.h>
983 #include <inet/ip6.h>
984
985 #include <sys/mac_impl.h>
986 #include <sys/mac_client_impl.h>
987 #include <sys/mac_client_priv.h>
988 #include <sys/mac_soft_ring.h>
989 #include <sys/mac_flow_impl.h>
990
991 static mac_tx_cookie_t mac_tx_single_ring_mode(mac_soft_ring_set_t *, mblk_t *,
992 uintptr_t, uint16_t, mblk_t **);
993 static mac_tx_cookie_t mac_tx_serializer_mode(mac_soft_ring_set_t *, mblk_t *,
994 uintptr_t, uint16_t, mblk_t **);
995 static mac_tx_cookie_t mac_tx_fanout_mode(mac_soft_ring_set_t *, mblk_t *,
996 uintptr_t, uint16_t, mblk_t **);
997 static mac_tx_cookie_t mac_tx_bw_mode(mac_soft_ring_set_t *, mblk_t *,
998 uintptr_t, uint16_t, mblk_t **);
999 static mac_tx_cookie_t mac_tx_aggr_mode(mac_soft_ring_set_t *, mblk_t *,
1000 uintptr_t, uint16_t, mblk_t **);
1001
1002 typedef struct mac_tx_mode_s {
1003 mac_tx_srs_mode_t mac_tx_mode;
1004 mac_tx_func_t mac_tx_func;
1005 } mac_tx_mode_t;
1006
1007 /*
1008 * There are seven modes of operation on the Tx side. These modes get set
1009 * in mac_tx_srs_setup(). Except for the experimental TX_SERIALIZE mode,
1010 * none of the other modes are user configurable. They get selected by
1011 * the system depending upon whether the link (or flow) has multiple Tx
1012 * rings or a bandwidth configured, or if the link is an aggr, etc.
1013 *
1014 * When the Tx SRS is operating in aggr mode (st_mode) or if there are
1015 * multiple Tx rings owned by Tx SRS, then each Tx ring (pseudo or
1016 * otherwise) will have a soft ring associated with it. These soft rings
1017 * are stored in srs_tx_soft_rings[] array.
1018 *
1019 * Additionally in the case of aggr, there is the st_soft_rings[] array
1020 * in the mac_srs_tx_t structure. This array is used to store the same
1021 * set of soft rings that are present in srs_tx_soft_rings[] array but
1022 * in a different manner. The soft ring associated with the pseudo Tx
1023 * ring is saved at mr_index (of the pseudo ring) in st_soft_rings[]
1024 * array. This helps in quickly getting the soft ring associated with the
1025 * Tx ring when aggr_find_tx_ring() returns the pseudo Tx ring that is to
1026 * be used for transmit.
1027 */
1028 mac_tx_mode_t mac_tx_mode_list[] = {
1029 {SRS_TX_DEFAULT, mac_tx_single_ring_mode},
1030 {SRS_TX_SERIALIZE, mac_tx_serializer_mode},
1031 {SRS_TX_FANOUT, mac_tx_fanout_mode},
1032 {SRS_TX_BW, mac_tx_bw_mode},
1033 {SRS_TX_BW_FANOUT, mac_tx_bw_mode},
1034 {SRS_TX_AGGR, mac_tx_aggr_mode},
1035 {SRS_TX_BW_AGGR, mac_tx_bw_mode}
1036 };
1037
1038 /*
1039 * Soft Ring Set (SRS) - The Run time code that deals with
1040 * dynamic polling from the hardware, bandwidth enforcement,
1041 * fanout etc.
1042 *
1043 * We try to use H/W classification on NIC and assign traffic for
1044 * a MAC address to a particular Rx ring or ring group. There is a
1045 * 1-1 mapping between a SRS and a Rx ring. The SRS dynamically
1046 * switches the underlying Rx ring between interrupt and
1047 * polling mode and enforces any specified B/W control.
1048 *
1049 * There is always a SRS created and tied to each H/W and S/W rule.
1050 * Whenever we create a H/W rule, we always add the the same rule to
1051 * S/W classifier and tie a SRS to it.
1052 *
1053 * In case a B/W control is specified, it is broken into bytes
1054 * per ticks and as soon as the quota for a tick is exhausted,
1055 * the underlying Rx ring is forced into poll mode for remainder of
1056 * the tick. The SRS poll thread only polls for bytes that are
1057 * allowed to come in the SRS. We typically let 4x the configured
1058 * B/W worth of packets to come in the SRS (to prevent unnecessary
1059 * drops due to bursts) but only process the specified amount.
1060 *
1061 * A MAC client (e.g. a VNIC or aggr) can have 1 or more
1062 * Rx rings (and corresponding SRSs) assigned to it. The SRS
1063 * in turn can have softrings to do protocol level fanout or
1064 * softrings to do S/W based fanout or both. In case the NIC
1065 * has no Rx rings, we do S/W classification to respective SRS.
1066 * The S/W classification rule is always setup and ready. This
1067 * allows the MAC layer to reassign Rx rings whenever needed
1068 * but packets still continue to flow via the default path and
1069 * getting S/W classified to correct SRS.
1070 *
1071 * The SRS's are used on both Tx and Rx side. They use the same
1072 * data structure but the processing routines have slightly different
1073 * semantics due to the fact that Rx side needs to do dynamic
1074 * polling etc.
1075 *
1076 * Dynamic Polling Notes
1077 * =====================
1078 *
1079 * Each Soft ring set is capable of switching its Rx ring between
1080 * interrupt and poll mode and actively 'polls' for packets in
1081 * poll mode. If the SRS is implementing a B/W limit, it makes
1082 * sure that only Max allowed packets are pulled in poll mode
1083 * and goes to poll mode as soon as B/W limit is exceeded. As
1084 * such, there are no overheads to implement B/W limits.
1085 *
1086 * In poll mode, its better to keep the pipeline going where the
1087 * SRS worker thread keeps processing packets and poll thread
1088 * keeps bringing more packets (specially if they get to run
1089 * on different CPUs). This also prevents the overheads associated
1090 * by excessive signalling (on NUMA machines, this can be
1091 * pretty devastating). The exception is latency optimized case
1092 * where worker thread does no work and interrupt and poll thread
1093 * are allowed to do their own drain.
1094 *
1095 * We use the following policy to control Dynamic Polling:
1096 * 1) We switch to poll mode anytime the processing
1097 * thread causes a backlog to build up in SRS and
1098 * its associated Soft Rings (sr_poll_pkt_cnt > 0).
1099 * 2) As long as the backlog stays under the low water
1100 * mark (sr_lowat), we poll the H/W for more packets.
1101 * 3) If the backlog (sr_poll_pkt_cnt) exceeds low
1102 * water mark, we stay in poll mode but don't poll
1103 * the H/W for more packets.
1104 * 4) Anytime in polling mode, if we poll the H/W for
1105 * packets and find nothing plus we have an existing
1106 * backlog (sr_poll_pkt_cnt > 0), we stay in polling
1107 * mode but don't poll the H/W for packets anymore
1108 * (let the polling thread go to sleep).
1109 * 5) Once the backlog is relived (packets are processed)
1110 * we reenable polling (by signalling the poll thread)
1111 * only when the backlog dips below sr_poll_thres.
1112 * 6) sr_hiwat is used exclusively when we are not
1113 * polling capable and is used to decide when to
1114 * drop packets so the SRS queue length doesn't grow
1115 * infinitely.
1116 *
1117 * NOTE: Also see the block level comment on top of mac_soft_ring.c
1118 */
1119
1120 /*
1121 * mac_latency_optimize
1122 *
1123 * Controls whether the poll thread can process the packets inline
1124 * or let the SRS worker thread do the processing. This applies if
1125 * the SRS was not being processed. For latency sensitive traffic,
1126 * this needs to be true to allow inline processing. For throughput
1127 * under load, this should be false.
1128 *
1129 * This (and other similar) tunable should be rolled into a link
1130 * or flow specific workload hint that can be set using dladm
1131 * linkprop (instead of multiple such tunables).
1132 */
1133 boolean_t mac_latency_optimize = B_TRUE;
1134
1135 /*
1136 * MAC_RX_SRS_ENQUEUE_CHAIN and MAC_TX_SRS_ENQUEUE_CHAIN
1137 *
1138 * queue a mp or chain in soft ring set and increment the
1139 * local count (srs_count) for the SRS and the shared counter
1140 * (srs_poll_pkt_cnt - shared between SRS and its soft rings
1141 * to track the total unprocessed packets for polling to work
1142 * correctly).
1143 *
1144 * The size (total bytes queued) counters are incremented only
1145 * if we are doing B/W control.
1146 */
1147 #define MAC_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz) { \
1148 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \
1149 if ((mac_srs)->srs_last != NULL) \
1150 (mac_srs)->srs_last->b_next = (head); \
1151 else \
1152 (mac_srs)->srs_first = (head); \
1153 (mac_srs)->srs_last = (tail); \
1154 (mac_srs)->srs_count += count; \
1155 }
1156
1157 #define MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz) { \
1158 mac_srs_rx_t *srs_rx = &(mac_srs)->srs_rx; \
1159 \
1160 MAC_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz); \
1161 srs_rx->sr_poll_pkt_cnt += count; \
1162 ASSERT(srs_rx->sr_poll_pkt_cnt > 0); \
1163 if ((mac_srs)->srs_type & SRST_BW_CONTROL) { \
1164 (mac_srs)->srs_size += (sz); \
1165 mutex_enter(&(mac_srs)->srs_bw->mac_bw_lock); \
1166 (mac_srs)->srs_bw->mac_bw_sz += (sz); \
1167 mutex_exit(&(mac_srs)->srs_bw->mac_bw_lock); \
1168 } \
1169 }
1170
1171 #define MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz) { \
1172 mac_srs->srs_state |= SRS_ENQUEUED; \
1173 MAC_SRS_ENQUEUE_CHAIN(mac_srs, head, tail, count, sz); \
1174 if ((mac_srs)->srs_type & SRST_BW_CONTROL) { \
1175 (mac_srs)->srs_size += (sz); \
1176 (mac_srs)->srs_bw->mac_bw_sz += (sz); \
1177 } \
1178 }
1179
1180 /*
1181 * Turn polling on routines
1182 */
1183 #define MAC_SRS_POLLING_ON(mac_srs) { \
1184 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \
1185 if (((mac_srs)->srs_state & \
1186 (SRS_POLLING_CAPAB|SRS_POLLING)) == SRS_POLLING_CAPAB) { \
1187 (mac_srs)->srs_state |= SRS_POLLING; \
1188 (void) mac_hwring_disable_intr((mac_ring_handle_t) \
1189 (mac_srs)->srs_ring); \
1190 (mac_srs)->srs_rx.sr_poll_on++; \
1191 } \
1192 }
1193
1194 #define MAC_SRS_WORKER_POLLING_ON(mac_srs) { \
1195 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \
1196 if (((mac_srs)->srs_state & \
1197 (SRS_POLLING_CAPAB|SRS_WORKER|SRS_POLLING)) == \
1198 (SRS_POLLING_CAPAB|SRS_WORKER)) { \
1199 (mac_srs)->srs_state |= SRS_POLLING; \
1200 (void) mac_hwring_disable_intr((mac_ring_handle_t) \
1201 (mac_srs)->srs_ring); \
1202 (mac_srs)->srs_rx.sr_worker_poll_on++; \
1203 } \
1204 }
1205
1206 /*
1207 * MAC_SRS_POLL_RING
1208 *
1209 * Signal the SRS poll thread to poll the underlying H/W ring
1210 * provided it wasn't already polling (SRS_GET_PKTS was set).
1211 *
1212 * Poll thread gets to run only from mac_rx_srs_drain() and only
1213 * if the drain was being done by the worker thread.
1214 */
1215 #define MAC_SRS_POLL_RING(mac_srs) { \
1216 mac_srs_rx_t *srs_rx = &(mac_srs)->srs_rx; \
1217 \
1218 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \
1219 srs_rx->sr_poll_thr_sig++; \
1220 if (((mac_srs)->srs_state & \
1221 (SRS_POLLING_CAPAB|SRS_WORKER|SRS_GET_PKTS)) == \
1222 (SRS_WORKER|SRS_POLLING_CAPAB)) { \
1223 (mac_srs)->srs_state |= SRS_GET_PKTS; \
1224 cv_signal(&(mac_srs)->srs_cv); \
1225 } else { \
1226 srs_rx->sr_poll_thr_busy++; \
1227 } \
1228 }
1229
1230 /*
1231 * MAC_SRS_CHECK_BW_CONTROL
1232 *
1233 * Check to see if next tick has started so we can reset the
1234 * SRS_BW_ENFORCED flag and allow more packets to come in the
1235 * system.
1236 */
1237 #define MAC_SRS_CHECK_BW_CONTROL(mac_srs) { \
1238 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \
1239 ASSERT(((mac_srs)->srs_type & SRST_TX) || \
1240 MUTEX_HELD(&(mac_srs)->srs_bw->mac_bw_lock)); \
1241 clock_t now = ddi_get_lbolt(); \
1242 if ((mac_srs)->srs_bw->mac_bw_curr_time != now) { \
1243 (mac_srs)->srs_bw->mac_bw_curr_time = now; \
1244 (mac_srs)->srs_bw->mac_bw_used = 0; \
1245 if ((mac_srs)->srs_bw->mac_bw_state & SRS_BW_ENFORCED) \
1246 (mac_srs)->srs_bw->mac_bw_state &= ~SRS_BW_ENFORCED; \
1247 } \
1248 }
1249
1250 /*
1251 * MAC_SRS_WORKER_WAKEUP
1252 *
1253 * Wake up the SRS worker thread to process the queue as long as
1254 * no one else is processing the queue. If we are optimizing for
1255 * latency, we wake up the worker thread immediately or else we
1256 * wait mac_srs_worker_wakeup_ticks before worker thread gets
1257 * woken up.
1258 */
1259 int mac_srs_worker_wakeup_ticks = 0;
1260 #define MAC_SRS_WORKER_WAKEUP(mac_srs) { \
1261 ASSERT(MUTEX_HELD(&(mac_srs)->srs_lock)); \
1262 if (!((mac_srs)->srs_state & SRS_PROC) && \
1263 (mac_srs)->srs_tid == NULL) { \
1264 if (((mac_srs)->srs_state & SRS_LATENCY_OPT) || \
1265 (mac_srs_worker_wakeup_ticks == 0)) \
1266 cv_signal(&(mac_srs)->srs_async); \
1267 else \
1268 (mac_srs)->srs_tid = \
1269 timeout(mac_srs_fire, (mac_srs), \
1270 mac_srs_worker_wakeup_ticks); \
1271 } \
1272 }
1273
1274 #define TX_BANDWIDTH_MODE(mac_srs) \
1275 ((mac_srs)->srs_tx.st_mode == SRS_TX_BW || \
1276 (mac_srs)->srs_tx.st_mode == SRS_TX_BW_FANOUT || \
1277 (mac_srs)->srs_tx.st_mode == SRS_TX_BW_AGGR)
1278
1279 #define TX_SRS_TO_SOFT_RING(mac_srs, head, hint) { \
1280 if (tx_mode == SRS_TX_BW_FANOUT) \
1281 (void) mac_tx_fanout_mode(mac_srs, head, hint, 0, NULL);\
1282 else \
1283 (void) mac_tx_aggr_mode(mac_srs, head, hint, 0, NULL); \
1284 }
1285
1286 /*
1287 * MAC_TX_SRS_BLOCK
1288 *
1289 * Always called from mac_tx_srs_drain() function. SRS_TX_BLOCKED
1290 * will be set only if srs_tx_woken_up is FALSE. If
1291 * srs_tx_woken_up is TRUE, it indicates that the wakeup arrived
1292 * before we grabbed srs_lock to set SRS_TX_BLOCKED. We need to
1293 * attempt to transmit again and not setting SRS_TX_BLOCKED does
1294 * that.
1295 */
1296 #define MAC_TX_SRS_BLOCK(srs, mp) { \
1297 ASSERT(MUTEX_HELD(&(srs)->srs_lock)); \
1298 if ((srs)->srs_tx.st_woken_up) { \
1299 (srs)->srs_tx.st_woken_up = B_FALSE; \
1300 } else { \
1301 ASSERT(!((srs)->srs_state & SRS_TX_BLOCKED)); \
1302 (srs)->srs_state |= SRS_TX_BLOCKED; \
1303 (srs)->srs_tx.st_stat.mts_blockcnt++; \
1304 } \
1305 }
1306
1307 /*
1308 * MAC_TX_SRS_TEST_HIWAT
1309 *
1310 * Called before queueing a packet onto Tx SRS to test and set
1311 * SRS_TX_HIWAT if srs_count exceeds srs_tx_hiwat.
1312 */
1313 #define MAC_TX_SRS_TEST_HIWAT(srs, mp, tail, cnt, sz, cookie) { \
1314 boolean_t enqueue = 1; \
1315 \
1316 if ((srs)->srs_count > (srs)->srs_tx.st_hiwat) { \
1317 /* \
1318 * flow-controlled. Store srs in cookie so that it \
1319 * can be returned as mac_tx_cookie_t to client \
1320 */ \
1321 (srs)->srs_state |= SRS_TX_HIWAT; \
1322 cookie = (mac_tx_cookie_t)srs; \
1323 (srs)->srs_tx.st_hiwat_cnt++; \
1324 if ((srs)->srs_count > (srs)->srs_tx.st_max_q_cnt) { \
1325 /* increment freed stats */ \
1326 (srs)->srs_tx.st_stat.mts_sdrops += cnt; \
1327 /* \
1328 * b_prev may be set to the fanout hint \
1329 * hence can't use freemsg directly \
1330 */ \
1331 mac_drop_chain(mp_chain, "SRS Tx max queue"); \
1332 DTRACE_PROBE1(tx_queued_hiwat, \
1333 mac_soft_ring_set_t *, srs); \
1334 enqueue = 0; \
1335 } \
1336 } \
1337 if (enqueue) \
1338 MAC_TX_SRS_ENQUEUE_CHAIN(srs, mp, tail, cnt, sz); \
1339 }
1340
1341 /* Some utility macros */
1342 #define MAC_SRS_BW_LOCK(srs) \
1343 if (!(srs->srs_type & SRST_TX)) \
1344 mutex_enter(&srs->srs_bw->mac_bw_lock);
1345
1346 #define MAC_SRS_BW_UNLOCK(srs) \
1347 if (!(srs->srs_type & SRST_TX)) \
1348 mutex_exit(&srs->srs_bw->mac_bw_lock);
1349
1350 #define MAC_TX_SRS_DROP_MESSAGE(srs, chain, cookie, s) { \
1351 mac_drop_chain((chain), (s)); \
1352 /* increment freed stats */ \
1353 (srs)->srs_tx.st_stat.mts_sdrops++; \
1354 (cookie) = (mac_tx_cookie_t)(srs); \
1355 }
1356
1357 #define MAC_TX_SET_NO_ENQUEUE(srs, mp_chain, ret_mp, cookie) { \
1358 mac_srs->srs_state |= SRS_TX_WAKEUP_CLIENT; \
1359 cookie = (mac_tx_cookie_t)srs; \
1360 *ret_mp = mp_chain; \
1361 }
1362
1363 /*
1364 * Threshold used in receive-side processing to determine if handling
1365 * can occur in situ (in the interrupt thread) or if it should be left to a
1366 * worker thread. Note that the constant used to make this determination is
1367 * not entirely made-up, and is a result of some emprical validation. That
1368 * said, the constant is left as a global variable to allow it to be
1369 * dynamically tuned in the field if and as needed.
1370 */
1371 uintptr_t mac_rx_srs_stack_needed = 14336;
1372 uint_t mac_rx_srs_stack_toodeep;
1373
1374 #ifndef STACK_GROWTH_DOWN
1375 #error Downward stack growth assumed.
1376 #endif
1377
1378 /*
1379 * Drop the rx packet and advance to the next one in the chain.
1380 */
1381 static void
mac_rx_drop_pkt(mac_soft_ring_set_t * srs,mblk_t * mp)1382 mac_rx_drop_pkt(mac_soft_ring_set_t *srs, mblk_t *mp)
1383 {
1384 mac_srs_rx_t *srs_rx = &srs->srs_rx;
1385
1386 ASSERT(mp->b_next == NULL);
1387 mutex_enter(&srs->srs_lock);
1388 MAC_UPDATE_SRS_COUNT_LOCKED(srs, 1);
1389 MAC_UPDATE_SRS_SIZE_LOCKED(srs, msgdsize(mp));
1390 mutex_exit(&srs->srs_lock);
1391
1392 srs_rx->sr_stat.mrs_sdrops++;
1393 freemsg(mp);
1394 }
1395
1396 /* DATAPATH RUNTIME ROUTINES */
1397
1398 /*
1399 * mac_srs_fire
1400 *
1401 * Timer callback routine for waking up the SRS worker thread.
1402 */
1403 static void
mac_srs_fire(void * arg)1404 mac_srs_fire(void *arg)
1405 {
1406 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)arg;
1407
1408 mutex_enter(&mac_srs->srs_lock);
1409 if (mac_srs->srs_tid == NULL) {
1410 mutex_exit(&mac_srs->srs_lock);
1411 return;
1412 }
1413
1414 mac_srs->srs_tid = NULL;
1415 if (!(mac_srs->srs_state & SRS_PROC))
1416 cv_signal(&mac_srs->srs_async);
1417
1418 mutex_exit(&mac_srs->srs_lock);
1419 }
1420
1421 /*
1422 * 'hint' is fanout_hint (type of uint64_t) which is given by the TCP/IP stack,
1423 * and it is used on the TX path.
1424 */
1425 #define HASH_HINT(hint) \
1426 ((hint) ^ ((hint) >> 24) ^ ((hint) >> 16) ^ ((hint) >> 8))
1427
1428
1429 /*
1430 * hash based on the src address, dst address and the port information.
1431 */
1432 #define HASH_ADDR(src, dst, ports) \
1433 (ntohl((src) + (dst)) ^ ((ports) >> 24) ^ ((ports) >> 16) ^ \
1434 ((ports) >> 8) ^ (ports))
1435
1436 #define COMPUTE_INDEX(key, sz) (key % sz)
1437
1438 #define FANOUT_ENQUEUE_MP(head, tail, cnt, bw_ctl, sz, sz0, mp) { \
1439 if ((tail) != NULL) { \
1440 ASSERT((tail)->b_next == NULL); \
1441 (tail)->b_next = (mp); \
1442 } else { \
1443 ASSERT((head) == NULL); \
1444 (head) = (mp); \
1445 } \
1446 (tail) = (mp); \
1447 (cnt)++; \
1448 if ((bw_ctl)) \
1449 (sz) += (sz0); \
1450 }
1451
1452 #define MAC_FANOUT_DEFAULT 0
1453 #define MAC_FANOUT_RND_ROBIN 1
1454 int mac_fanout_type = MAC_FANOUT_DEFAULT;
1455
1456 #define MAX_SR_TYPES 3
1457 /* fanout types for port based hashing */
1458 enum pkt_type {
1459 V4_TCP = 0,
1460 V4_UDP,
1461 OTH,
1462 UNDEF
1463 };
1464
1465 /*
1466 * Pair of local and remote ports in the transport header
1467 */
1468 #define PORTS_SIZE 4
1469
1470 /*
1471 * This routine delivers packets destined for an SRS into one of the
1472 * protocol soft rings.
1473 *
1474 * Given a chain of packets we need to split it up into multiple sub
1475 * chains: TCP, UDP or OTH soft ring. Instead of entering the soft
1476 * ring one packet at a time, we want to enter it in the form of a
1477 * chain otherwise we get this start/stop behaviour where the worker
1478 * thread goes to sleep and then next packet comes in forcing it to
1479 * wake up.
1480 */
1481 static void
mac_rx_srs_proto_fanout(mac_soft_ring_set_t * mac_srs,mblk_t * head)1482 mac_rx_srs_proto_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *head)
1483 {
1484 struct ether_header *ehp;
1485 struct ether_vlan_header *evhp;
1486 uint32_t sap;
1487 ipha_t *ipha;
1488 uint8_t *dstaddr;
1489 size_t hdrsize;
1490 mblk_t *mp;
1491 mblk_t *headmp[MAX_SR_TYPES];
1492 mblk_t *tailmp[MAX_SR_TYPES];
1493 int cnt[MAX_SR_TYPES];
1494 size_t sz[MAX_SR_TYPES];
1495 size_t sz1;
1496 boolean_t bw_ctl;
1497 boolean_t hw_classified;
1498 boolean_t dls_bypass;
1499 boolean_t is_ether;
1500 boolean_t is_unicast;
1501 enum pkt_type type;
1502 mac_client_impl_t *mcip = mac_srs->srs_mcip;
1503
1504 is_ether = (mcip->mci_mip->mi_info.mi_nativemedia == DL_ETHER);
1505 bw_ctl = ((mac_srs->srs_type & SRST_BW_CONTROL) != 0);
1506
1507 /*
1508 * If we don't have a Rx ring, S/W classification would have done
1509 * its job and its a packet meant for us. If we were polling on
1510 * the default ring (i.e. there was a ring assigned to this SRS),
1511 * then we need to make sure that the mac address really belongs
1512 * to us.
1513 */
1514 hw_classified = mac_srs->srs_ring != NULL &&
1515 mac_srs->srs_ring->mr_classify_type == MAC_HW_CLASSIFIER;
1516
1517 /*
1518 * Some clients, such as non-ethernet, need DLS processing in
1519 * the Rx path. Such clients clear the SRST_DLS_BYPASS flag.
1520 * DLS bypass may also be disabled via the
1521 * MCIS_RX_BYPASS_DISABLE flag.
1522 */
1523 dls_bypass = ((mac_srs->srs_type & SRST_DLS_BYPASS) != 0) &&
1524 ((mcip->mci_state_flags & MCIS_RX_BYPASS_DISABLE) == 0);
1525
1526 bzero(headmp, MAX_SR_TYPES * sizeof (mblk_t *));
1527 bzero(tailmp, MAX_SR_TYPES * sizeof (mblk_t *));
1528 bzero(cnt, MAX_SR_TYPES * sizeof (int));
1529 bzero(sz, MAX_SR_TYPES * sizeof (size_t));
1530
1531 /*
1532 * We have a chain from SRS that we need to split across the
1533 * soft rings. The squeues for the TCP and IPv4 SAPs use their
1534 * own soft rings to allow polling from the squeue. The rest of
1535 * the packets are delivered on the OTH soft ring which cannot
1536 * be polled.
1537 */
1538 while (head != NULL) {
1539 mp = head;
1540 head = head->b_next;
1541 mp->b_next = NULL;
1542
1543 type = OTH;
1544 sz1 = (mp->b_cont == NULL) ? MBLKL(mp) : msgdsize(mp);
1545
1546 if (is_ether) {
1547 /*
1548 * At this point we can be sure the packet at least
1549 * has an ether header.
1550 */
1551 if (sz1 < sizeof (struct ether_header)) {
1552 mac_rx_drop_pkt(mac_srs, mp);
1553 continue;
1554 }
1555 ehp = (struct ether_header *)mp->b_rptr;
1556
1557 /*
1558 * Determine if this is a VLAN or non-VLAN packet.
1559 */
1560 if ((sap = ntohs(ehp->ether_type)) == VLAN_TPID) {
1561 evhp = (struct ether_vlan_header *)mp->b_rptr;
1562 sap = ntohs(evhp->ether_type);
1563 hdrsize = sizeof (struct ether_vlan_header);
1564
1565 /*
1566 * Check if the VID of the packet, if
1567 * any, belongs to this client.
1568 * Technically, if this packet came up
1569 * via a HW classified ring then we
1570 * don't need to perform this check.
1571 * Perhaps a future optimization.
1572 */
1573 if (!mac_client_check_flow_vid(mcip,
1574 VLAN_ID(ntohs(evhp->ether_tci)))) {
1575 mac_rx_drop_pkt(mac_srs, mp);
1576 continue;
1577 }
1578 } else {
1579 hdrsize = sizeof (struct ether_header);
1580 }
1581 is_unicast =
1582 ((((uint8_t *)&ehp->ether_dhost)[0] & 0x01) == 0);
1583 dstaddr = (uint8_t *)&ehp->ether_dhost;
1584 } else {
1585 mac_header_info_t mhi;
1586
1587 if (mac_header_info((mac_handle_t)mcip->mci_mip,
1588 mp, &mhi) != 0) {
1589 mac_rx_drop_pkt(mac_srs, mp);
1590 continue;
1591 }
1592 hdrsize = mhi.mhi_hdrsize;
1593 sap = mhi.mhi_bindsap;
1594 is_unicast = (mhi.mhi_dsttype == MAC_ADDRTYPE_UNICAST);
1595 dstaddr = (uint8_t *)mhi.mhi_daddr;
1596 }
1597
1598 if (!dls_bypass) {
1599 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type],
1600 cnt[type], bw_ctl, sz[type], sz1, mp);
1601 continue;
1602 }
1603
1604 if (sap == ETHERTYPE_IP) {
1605 /*
1606 * If we are H/W classified, but we have promisc
1607 * on, then we need to check for the unicast address.
1608 */
1609 if (hw_classified && mcip->mci_promisc_list != NULL) {
1610 mac_address_t *map;
1611
1612 rw_enter(&mcip->mci_rw_lock, RW_READER);
1613 map = mcip->mci_unicast;
1614 if (bcmp(dstaddr, map->ma_addr,
1615 map->ma_len) == 0)
1616 type = UNDEF;
1617 rw_exit(&mcip->mci_rw_lock);
1618 } else if (is_unicast) {
1619 type = UNDEF;
1620 }
1621 }
1622
1623 /*
1624 * This needs to become a contract with the driver for
1625 * the fast path.
1626 *
1627 * In the normal case the packet will have at least the L2
1628 * header and the IP + Transport header in the same mblk.
1629 * This is usually the case when the NIC driver sends up
1630 * the packet. This is also true when the stack generates
1631 * a packet that is looped back and when the stack uses the
1632 * fastpath mechanism. The normal case is optimized for
1633 * performance and may bypass DLS. All other cases go through
1634 * the 'OTH' type path without DLS bypass.
1635 */
1636 ipha = (ipha_t *)(mp->b_rptr + hdrsize);
1637 if ((type != OTH) && MBLK_RX_FANOUT_SLOWPATH(mp, ipha))
1638 type = OTH;
1639
1640 if (type == OTH) {
1641 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type],
1642 cnt[type], bw_ctl, sz[type], sz1, mp);
1643 continue;
1644 }
1645
1646 ASSERT(type == UNDEF);
1647
1648 /*
1649 * Determine the type from the IP protocol value. If
1650 * classified as TCP or UDP, then update the read
1651 * pointer to the beginning of the IP header.
1652 * Otherwise leave the message as is for further
1653 * processing by DLS.
1654 */
1655 switch (ipha->ipha_protocol) {
1656 case IPPROTO_TCP:
1657 type = V4_TCP;
1658 mp->b_rptr += hdrsize;
1659 break;
1660 case IPPROTO_UDP:
1661 type = V4_UDP;
1662 mp->b_rptr += hdrsize;
1663 break;
1664 default:
1665 type = OTH;
1666 break;
1667 }
1668
1669 FANOUT_ENQUEUE_MP(headmp[type], tailmp[type], cnt[type],
1670 bw_ctl, sz[type], sz1, mp);
1671 }
1672
1673 for (type = V4_TCP; type < UNDEF; type++) {
1674 if (headmp[type] != NULL) {
1675 mac_soft_ring_t *softring;
1676
1677 ASSERT(tailmp[type]->b_next == NULL);
1678 switch (type) {
1679 case V4_TCP:
1680 softring = mac_srs->srs_tcp_soft_rings[0];
1681 break;
1682 case V4_UDP:
1683 softring = mac_srs->srs_udp_soft_rings[0];
1684 break;
1685 case OTH:
1686 softring = mac_srs->srs_oth_soft_rings[0];
1687 }
1688 mac_rx_soft_ring_process(mcip, softring,
1689 headmp[type], tailmp[type], cnt[type], sz[type]);
1690 }
1691 }
1692 }
1693
1694 int fanout_unaligned = 0;
1695
1696 /*
1697 * The fanout routine for any clients with DLS bypass disabled or for
1698 * traffic classified as "other". Returns -1 on an error (drop the
1699 * packet due to a malformed packet), 0 on success, with values
1700 * written in *indx and *type.
1701 */
1702 static int
mac_rx_srs_long_fanout(mac_soft_ring_set_t * mac_srs,mblk_t * mp,uint32_t sap,size_t hdrsize,enum pkt_type * type,uint_t * indx)1703 mac_rx_srs_long_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *mp,
1704 uint32_t sap, size_t hdrsize, enum pkt_type *type, uint_t *indx)
1705 {
1706 ip6_t *ip6h;
1707 ipha_t *ipha;
1708 uint8_t *whereptr;
1709 uint_t hash;
1710 uint16_t remlen;
1711 uint8_t nexthdr;
1712 uint16_t hdr_len;
1713 uint32_t src_val, dst_val;
1714 boolean_t modifiable = B_TRUE;
1715 boolean_t v6;
1716
1717 ASSERT(MBLKL(mp) >= hdrsize);
1718
1719 if (sap == ETHERTYPE_IPV6) {
1720 v6 = B_TRUE;
1721 hdr_len = IPV6_HDR_LEN;
1722 } else if (sap == ETHERTYPE_IP) {
1723 v6 = B_FALSE;
1724 hdr_len = IP_SIMPLE_HDR_LENGTH;
1725 } else {
1726 *indx = 0;
1727 *type = OTH;
1728 return (0);
1729 }
1730
1731 ip6h = (ip6_t *)(mp->b_rptr + hdrsize);
1732 ipha = (ipha_t *)ip6h;
1733
1734 if ((uint8_t *)ip6h == mp->b_wptr) {
1735 /*
1736 * The first mblk_t only includes the mac header.
1737 * Note that it is safe to change the mp pointer here,
1738 * as the subsequent operation does not assume mp
1739 * points to the start of the mac header.
1740 */
1741 mp = mp->b_cont;
1742
1743 /*
1744 * Make sure the IP header points to an entire one.
1745 */
1746 if (mp == NULL)
1747 return (-1);
1748
1749 if (MBLKL(mp) < hdr_len) {
1750 modifiable = (DB_REF(mp) == 1);
1751
1752 if (modifiable && !pullupmsg(mp, hdr_len))
1753 return (-1);
1754 }
1755
1756 ip6h = (ip6_t *)mp->b_rptr;
1757 ipha = (ipha_t *)ip6h;
1758 }
1759
1760 if (!modifiable || !(OK_32PTR((char *)ip6h)) ||
1761 ((uint8_t *)ip6h + hdr_len > mp->b_wptr)) {
1762 /*
1763 * If either the IP header is not aligned, or it does not hold
1764 * the complete simple structure (a pullupmsg() is not an
1765 * option since it would result in an unaligned IP header),
1766 * fanout to the default ring.
1767 *
1768 * Note that this may cause packet reordering.
1769 */
1770 *indx = 0;
1771 *type = OTH;
1772 fanout_unaligned++;
1773 return (0);
1774 }
1775
1776 /*
1777 * Extract next-header, full header length, and source-hash value
1778 * using v4/v6 specific fields.
1779 */
1780 if (v6) {
1781 remlen = ntohs(ip6h->ip6_plen);
1782 nexthdr = ip6h->ip6_nxt;
1783 src_val = V4_PART_OF_V6(ip6h->ip6_src);
1784 dst_val = V4_PART_OF_V6(ip6h->ip6_dst);
1785 /*
1786 * Do src based fanout if below tunable is set to B_TRUE or
1787 * when mac_ip_hdr_length_v6() fails because of malformed
1788 * packets or because mblks need to be concatenated using
1789 * pullupmsg().
1790 *
1791 * Perform a version check to prevent parsing weirdness...
1792 */
1793 if (IPH_HDR_VERSION(ip6h) != IPV6_VERSION ||
1794 !mac_ip_hdr_length_v6(ip6h, mp->b_wptr, &hdr_len, &nexthdr,
1795 NULL)) {
1796 goto src_dst_based_fanout;
1797 }
1798 } else {
1799 hdr_len = IPH_HDR_LENGTH(ipha);
1800 remlen = ntohs(ipha->ipha_length) - hdr_len;
1801 nexthdr = ipha->ipha_protocol;
1802 src_val = (uint32_t)ipha->ipha_src;
1803 dst_val = (uint32_t)ipha->ipha_dst;
1804 /*
1805 * Catch IPv4 fragment case here. IPv6 has nexthdr == FRAG
1806 * for its equivalent case.
1807 */
1808 if ((ntohs(ipha->ipha_fragment_offset_and_flags) &
1809 (IPH_MF | IPH_OFFSET)) != 0) {
1810 goto src_dst_based_fanout;
1811 }
1812 }
1813 if (remlen < MIN_EHDR_LEN)
1814 return (-1);
1815 whereptr = (uint8_t *)ip6h + hdr_len;
1816
1817 /* If the transport is one of below, we do port/SPI based fanout */
1818 switch (nexthdr) {
1819 case IPPROTO_TCP:
1820 case IPPROTO_UDP:
1821 case IPPROTO_SCTP:
1822 case IPPROTO_ESP:
1823 /*
1824 * If the ports or SPI in the transport header is not part of
1825 * the mblk, do src_based_fanout, instead of calling
1826 * pullupmsg().
1827 */
1828 if (mp->b_cont == NULL || whereptr + PORTS_SIZE <= mp->b_wptr)
1829 break; /* out of switch... */
1830 /* FALLTHRU */
1831 default:
1832 goto src_dst_based_fanout;
1833 }
1834
1835 switch (nexthdr) {
1836 case IPPROTO_TCP:
1837 hash = HASH_ADDR(src_val, dst_val, *(uint32_t *)whereptr);
1838 *indx = COMPUTE_INDEX(hash, mac_srs->srs_tcp_ring_count);
1839 *type = OTH;
1840 break;
1841 case IPPROTO_UDP:
1842 case IPPROTO_SCTP:
1843 case IPPROTO_ESP:
1844 if (mac_fanout_type == MAC_FANOUT_DEFAULT) {
1845 hash = HASH_ADDR(src_val, dst_val,
1846 *(uint32_t *)whereptr);
1847 *indx = COMPUTE_INDEX(hash,
1848 mac_srs->srs_udp_ring_count);
1849 } else {
1850 *indx = mac_srs->srs_ind % mac_srs->srs_udp_ring_count;
1851 mac_srs->srs_ind++;
1852 }
1853 *type = OTH;
1854 break;
1855 }
1856 return (0);
1857
1858 src_dst_based_fanout:
1859 hash = HASH_ADDR(src_val, dst_val, (uint32_t)0);
1860 *indx = COMPUTE_INDEX(hash, mac_srs->srs_oth_ring_count);
1861 *type = OTH;
1862 return (0);
1863 }
1864
1865 /*
1866 * This routine delivers packets destined for an SRS into a soft ring member
1867 * of the set.
1868 *
1869 * Given a chain of packets we need to split it up into multiple sub
1870 * chains: TCP, UDP or OTH soft ring. Instead of entering the soft
1871 * ring one packet at a time, we want to enter it in the form of a
1872 * chain otherwise we get this start/stop behaviour where the worker
1873 * thread goes to sleep and then next packet comes in forcing it to
1874 * wake up.
1875 *
1876 * Note:
1877 * Since we know what is the maximum fanout possible, we create a 2D array
1878 * of 'softring types * MAX_SR_FANOUT' for the head, tail, cnt and sz
1879 * variables so that we can enter the softrings with chain. We need the
1880 * MAX_SR_FANOUT so we can allocate the arrays on the stack (a kmem_alloc
1881 * for each packet would be expensive). If we ever want to have the
1882 * ability to have unlimited fanout, we should probably declare a head,
1883 * tail, cnt, sz with each soft ring (a data struct which contains a softring
1884 * along with these members) and create an array of this uber struct so we
1885 * don't have to do kmem_alloc.
1886 */
1887 int fanout_oth1 = 0;
1888 int fanout_oth2 = 0;
1889 int fanout_oth3 = 0;
1890 int fanout_oth4 = 0;
1891 int fanout_oth5 = 0;
1892
1893 static void
mac_rx_srs_fanout(mac_soft_ring_set_t * mac_srs,mblk_t * head)1894 mac_rx_srs_fanout(mac_soft_ring_set_t *mac_srs, mblk_t *head)
1895 {
1896 struct ether_header *ehp;
1897 struct ether_vlan_header *evhp;
1898 uint32_t sap;
1899 ipha_t *ipha;
1900 uint8_t *dstaddr;
1901 uint_t indx;
1902 size_t ports_offset;
1903 size_t ipha_len;
1904 size_t hdrsize;
1905 uint_t hash;
1906 mblk_t *mp;
1907 mblk_t *headmp[MAX_SR_TYPES][MAX_SR_FANOUT];
1908 mblk_t *tailmp[MAX_SR_TYPES][MAX_SR_FANOUT];
1909 int cnt[MAX_SR_TYPES][MAX_SR_FANOUT];
1910 size_t sz[MAX_SR_TYPES][MAX_SR_FANOUT];
1911 size_t sz1;
1912 boolean_t bw_ctl;
1913 boolean_t hw_classified;
1914 boolean_t dls_bypass;
1915 boolean_t is_ether;
1916 boolean_t is_unicast;
1917 int fanout_cnt;
1918 enum pkt_type type;
1919 mac_client_impl_t *mcip = mac_srs->srs_mcip;
1920
1921 is_ether = (mcip->mci_mip->mi_info.mi_nativemedia == DL_ETHER);
1922 bw_ctl = ((mac_srs->srs_type & SRST_BW_CONTROL) != 0);
1923
1924 /*
1925 * If we don't have a Rx ring, S/W classification would have done
1926 * its job and its a packet meant for us. If we were polling on
1927 * the default ring (i.e. there was a ring assigned to this SRS),
1928 * then we need to make sure that the mac address really belongs
1929 * to us.
1930 */
1931 hw_classified = mac_srs->srs_ring != NULL &&
1932 mac_srs->srs_ring->mr_classify_type == MAC_HW_CLASSIFIER;
1933
1934 /*
1935 * Some clients, such as non Ethernet, need DLS processing in
1936 * the Rx path. Such clients clear the SRST_DLS_BYPASS flag.
1937 * DLS bypass may also be disabled via the
1938 * MCIS_RX_BYPASS_DISABLE flag, but this is only consumed by
1939 * sun4v vsw currently.
1940 */
1941 dls_bypass = ((mac_srs->srs_type & SRST_DLS_BYPASS) != 0) &&
1942 ((mcip->mci_state_flags & MCIS_RX_BYPASS_DISABLE) == 0);
1943
1944 /*
1945 * Since the softrings are never destroyed and we always
1946 * create equal number of softrings for TCP, UDP and rest,
1947 * its OK to check one of them for count and use it without
1948 * any lock. In future, if soft rings get destroyed because
1949 * of reduction in fanout, we will need to ensure that happens
1950 * behind the SRS_PROC.
1951 */
1952 fanout_cnt = mac_srs->srs_tcp_ring_count;
1953
1954 bzero(headmp, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (mblk_t *));
1955 bzero(tailmp, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (mblk_t *));
1956 bzero(cnt, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (int));
1957 bzero(sz, MAX_SR_TYPES * MAX_SR_FANOUT * sizeof (size_t));
1958
1959 /*
1960 * We got a chain from SRS that we need to send to the soft rings.
1961 * Since squeues for TCP & IPv4 SAP poll their soft rings (for
1962 * performance reasons), we need to separate out v4_tcp, v4_udp
1963 * and the rest goes in other.
1964 */
1965 while (head != NULL) {
1966 mp = head;
1967 head = head->b_next;
1968 mp->b_next = NULL;
1969
1970 type = OTH;
1971 sz1 = (mp->b_cont == NULL) ? MBLKL(mp) : msgdsize(mp);
1972
1973 if (is_ether) {
1974 /*
1975 * At this point we can be sure the packet at least
1976 * has an ether header.
1977 */
1978 if (sz1 < sizeof (struct ether_header)) {
1979 mac_rx_drop_pkt(mac_srs, mp);
1980 continue;
1981 }
1982 ehp = (struct ether_header *)mp->b_rptr;
1983
1984 /*
1985 * Determine if this is a VLAN or non-VLAN packet.
1986 */
1987 if ((sap = ntohs(ehp->ether_type)) == VLAN_TPID) {
1988 evhp = (struct ether_vlan_header *)mp->b_rptr;
1989 sap = ntohs(evhp->ether_type);
1990 hdrsize = sizeof (struct ether_vlan_header);
1991
1992 /*
1993 * Check if the VID of the packet, if
1994 * any, belongs to this client.
1995 * Technically, if this packet came up
1996 * via a HW classified ring then we
1997 * don't need to perform this check.
1998 * Perhaps a future optimization.
1999 */
2000 if (!mac_client_check_flow_vid(mcip,
2001 VLAN_ID(ntohs(evhp->ether_tci)))) {
2002 mac_rx_drop_pkt(mac_srs, mp);
2003 continue;
2004 }
2005 } else {
2006 hdrsize = sizeof (struct ether_header);
2007 }
2008 is_unicast =
2009 ((((uint8_t *)&ehp->ether_dhost)[0] & 0x01) == 0);
2010 dstaddr = (uint8_t *)&ehp->ether_dhost;
2011 } else {
2012 mac_header_info_t mhi;
2013
2014 if (mac_header_info((mac_handle_t)mcip->mci_mip,
2015 mp, &mhi) != 0) {
2016 mac_rx_drop_pkt(mac_srs, mp);
2017 continue;
2018 }
2019 hdrsize = mhi.mhi_hdrsize;
2020 sap = mhi.mhi_bindsap;
2021 is_unicast = (mhi.mhi_dsttype == MAC_ADDRTYPE_UNICAST);
2022 dstaddr = (uint8_t *)mhi.mhi_daddr;
2023 }
2024
2025 if (!dls_bypass) {
2026 if (mac_rx_srs_long_fanout(mac_srs, mp, sap,
2027 hdrsize, &type, &indx) == -1) {
2028 mac_rx_drop_pkt(mac_srs, mp);
2029 continue;
2030 }
2031
2032 FANOUT_ENQUEUE_MP(headmp[type][indx],
2033 tailmp[type][indx], cnt[type][indx], bw_ctl,
2034 sz[type][indx], sz1, mp);
2035 continue;
2036 }
2037
2038 /*
2039 * If we are using the default Rx ring where H/W or S/W
2040 * classification has not happened, we need to verify if
2041 * this unicast packet really belongs to us.
2042 */
2043 if (sap == ETHERTYPE_IP) {
2044 /*
2045 * If we are H/W classified, but we have promisc
2046 * on, then we need to check for the unicast address.
2047 */
2048 if (hw_classified && mcip->mci_promisc_list != NULL) {
2049 mac_address_t *map;
2050
2051 rw_enter(&mcip->mci_rw_lock, RW_READER);
2052 map = mcip->mci_unicast;
2053 if (bcmp(dstaddr, map->ma_addr,
2054 map->ma_len) == 0)
2055 type = UNDEF;
2056 rw_exit(&mcip->mci_rw_lock);
2057 } else if (is_unicast) {
2058 type = UNDEF;
2059 }
2060 }
2061
2062 /*
2063 * This needs to become a contract with the driver for
2064 * the fast path.
2065 */
2066
2067 ipha = (ipha_t *)(mp->b_rptr + hdrsize);
2068 if ((type != OTH) && MBLK_RX_FANOUT_SLOWPATH(mp, ipha)) {
2069 type = OTH;
2070 fanout_oth1++;
2071 }
2072
2073 if (type != OTH) {
2074 uint16_t frag_offset_flags;
2075
2076 switch (ipha->ipha_protocol) {
2077 case IPPROTO_TCP:
2078 case IPPROTO_UDP:
2079 case IPPROTO_SCTP:
2080 case IPPROTO_ESP:
2081 ipha_len = IPH_HDR_LENGTH(ipha);
2082 if ((uchar_t *)ipha + ipha_len + PORTS_SIZE >
2083 mp->b_wptr) {
2084 type = OTH;
2085 break;
2086 }
2087 frag_offset_flags =
2088 ntohs(ipha->ipha_fragment_offset_and_flags);
2089 if ((frag_offset_flags &
2090 (IPH_MF | IPH_OFFSET)) != 0) {
2091 type = OTH;
2092 fanout_oth3++;
2093 break;
2094 }
2095 ports_offset = hdrsize + ipha_len;
2096 break;
2097 default:
2098 type = OTH;
2099 fanout_oth4++;
2100 break;
2101 }
2102 }
2103
2104 if (type == OTH) {
2105 if (mac_rx_srs_long_fanout(mac_srs, mp, sap,
2106 hdrsize, &type, &indx) == -1) {
2107 mac_rx_drop_pkt(mac_srs, mp);
2108 continue;
2109 }
2110
2111 FANOUT_ENQUEUE_MP(headmp[type][indx],
2112 tailmp[type][indx], cnt[type][indx], bw_ctl,
2113 sz[type][indx], sz1, mp);
2114 continue;
2115 }
2116
2117 ASSERT(type == UNDEF);
2118
2119 /*
2120 * XXX-Sunay: We should hold srs_lock since ring_count
2121 * below can change. But if we are always called from
2122 * mac_rx_srs_drain and SRS_PROC is set, then we can
2123 * enforce that ring_count can't be changed i.e.
2124 * to change fanout type or ring count, the calling
2125 * thread needs to be behind SRS_PROC.
2126 */
2127 switch (ipha->ipha_protocol) {
2128 case IPPROTO_TCP:
2129 /*
2130 * Note that for ESP, we fanout on SPI and it is at the
2131 * same offset as the 2x16-bit ports. So it is clumped
2132 * along with TCP, UDP and SCTP.
2133 */
2134 hash = HASH_ADDR(ipha->ipha_src, ipha->ipha_dst,
2135 *(uint32_t *)(mp->b_rptr + ports_offset));
2136 indx = COMPUTE_INDEX(hash, mac_srs->srs_tcp_ring_count);
2137 type = V4_TCP;
2138 mp->b_rptr += hdrsize;
2139 break;
2140 case IPPROTO_UDP:
2141 case IPPROTO_SCTP:
2142 case IPPROTO_ESP:
2143 if (mac_fanout_type == MAC_FANOUT_DEFAULT) {
2144 hash = HASH_ADDR(ipha->ipha_src, ipha->ipha_dst,
2145 *(uint32_t *)(mp->b_rptr + ports_offset));
2146 indx = COMPUTE_INDEX(hash,
2147 mac_srs->srs_udp_ring_count);
2148 } else {
2149 indx = mac_srs->srs_ind %
2150 mac_srs->srs_udp_ring_count;
2151 mac_srs->srs_ind++;
2152 }
2153 type = V4_UDP;
2154 mp->b_rptr += hdrsize;
2155 break;
2156 default:
2157 indx = 0;
2158 type = OTH;
2159 }
2160
2161 FANOUT_ENQUEUE_MP(headmp[type][indx], tailmp[type][indx],
2162 cnt[type][indx], bw_ctl, sz[type][indx], sz1, mp);
2163 }
2164
2165 for (type = V4_TCP; type < UNDEF; type++) {
2166 int i;
2167
2168 for (i = 0; i < fanout_cnt; i++) {
2169 if (headmp[type][i] != NULL) {
2170 mac_soft_ring_t *softring;
2171
2172 ASSERT(tailmp[type][i]->b_next == NULL);
2173 switch (type) {
2174 case V4_TCP:
2175 softring =
2176 mac_srs->srs_tcp_soft_rings[i];
2177 break;
2178 case V4_UDP:
2179 softring =
2180 mac_srs->srs_udp_soft_rings[i];
2181 break;
2182 case OTH:
2183 softring =
2184 mac_srs->srs_oth_soft_rings[i];
2185 break;
2186 }
2187 mac_rx_soft_ring_process(mcip,
2188 softring, headmp[type][i], tailmp[type][i],
2189 cnt[type][i], sz[type][i]);
2190 }
2191 }
2192 }
2193 }
2194
2195 #define SRS_BYTES_TO_PICKUP 150000
2196 ssize_t max_bytes_to_pickup = SRS_BYTES_TO_PICKUP;
2197
2198 /*
2199 * mac_rx_srs_poll_ring
2200 *
2201 * This SRS Poll thread uses this routine to poll the underlying hardware
2202 * Rx ring to get a chain of packets. It can inline process that chain
2203 * if mac_latency_optimize is set (default) or signal the SRS worker thread
2204 * to do the remaining processing.
2205 *
2206 * Since packets come in the system via interrupt or poll path, we also
2207 * update the stats and deal with promiscous clients here.
2208 */
2209 void
mac_rx_srs_poll_ring(mac_soft_ring_set_t * mac_srs)2210 mac_rx_srs_poll_ring(mac_soft_ring_set_t *mac_srs)
2211 {
2212 kmutex_t *lock = &mac_srs->srs_lock;
2213 kcondvar_t *async = &mac_srs->srs_cv;
2214 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx;
2215 mblk_t *head, *tail, *mp;
2216 callb_cpr_t cprinfo;
2217 ssize_t bytes_to_pickup;
2218 size_t sz;
2219 int count;
2220 mac_client_impl_t *smcip;
2221
2222 CALLB_CPR_INIT(&cprinfo, lock, callb_generic_cpr, "mac_srs_poll");
2223 mutex_enter(lock);
2224
2225 start:
2226 for (;;) {
2227 if (mac_srs->srs_state & SRS_PAUSE)
2228 goto done;
2229
2230 CALLB_CPR_SAFE_BEGIN(&cprinfo);
2231 cv_wait(async, lock);
2232 CALLB_CPR_SAFE_END(&cprinfo, lock);
2233
2234 if (mac_srs->srs_state & SRS_PAUSE)
2235 goto done;
2236
2237 check_again:
2238 if (mac_srs->srs_type & SRST_BW_CONTROL) {
2239 /*
2240 * We pick as many bytes as we are allowed to queue.
2241 * Its possible that we will exceed the total
2242 * packets queued in case this SRS is part of the
2243 * Rx ring group since > 1 poll thread can be pulling
2244 * upto the max allowed packets at the same time
2245 * but that should be OK.
2246 */
2247 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
2248 bytes_to_pickup =
2249 mac_srs->srs_bw->mac_bw_drop_threshold -
2250 mac_srs->srs_bw->mac_bw_sz;
2251 /*
2252 * We shouldn't have been signalled if we
2253 * have 0 or less bytes to pick but since
2254 * some of the bytes accounting is driver
2255 * dependant, we do the safety check.
2256 */
2257 if (bytes_to_pickup < 0)
2258 bytes_to_pickup = 0;
2259 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2260 } else {
2261 /*
2262 * ToDO: Need to change the polling API
2263 * to add a packet count and a flag which
2264 * tells the driver whether we want packets
2265 * based on a count, or bytes, or all the
2266 * packets queued in the driver/HW. This
2267 * way, we never have to check the limits
2268 * on poll path. We truly let only as many
2269 * packets enter the system as we are willing
2270 * to process or queue.
2271 *
2272 * Something along the lines of
2273 * pkts_to_pickup = mac_soft_ring_max_q_cnt -
2274 * mac_srs->srs_poll_pkt_cnt
2275 */
2276
2277 /*
2278 * Since we are not doing B/W control, pick
2279 * as many packets as allowed.
2280 */
2281 bytes_to_pickup = max_bytes_to_pickup;
2282 }
2283
2284 /* Poll the underlying Hardware */
2285 mutex_exit(lock);
2286 head = MAC_HWRING_POLL(mac_srs->srs_ring, (int)bytes_to_pickup);
2287 mutex_enter(lock);
2288
2289 ASSERT((mac_srs->srs_state & SRS_POLL_THR_OWNER) ==
2290 SRS_POLL_THR_OWNER);
2291
2292 mp = tail = head;
2293 count = 0;
2294 sz = 0;
2295 while (mp != NULL) {
2296 tail = mp;
2297 sz += msgdsize(mp);
2298 mp = mp->b_next;
2299 count++;
2300 }
2301
2302 if (head != NULL) {
2303 tail->b_next = NULL;
2304 smcip = mac_srs->srs_mcip;
2305
2306 SRS_RX_STAT_UPDATE(mac_srs, pollbytes, sz);
2307 SRS_RX_STAT_UPDATE(mac_srs, pollcnt, count);
2308
2309 /*
2310 * If there are any promiscuous mode callbacks
2311 * defined for this MAC client, pass them a copy
2312 * if appropriate and also update the counters.
2313 */
2314 if (smcip != NULL) {
2315 if (smcip->mci_mip->mi_promisc_list != NULL) {
2316 mutex_exit(lock);
2317 mac_promisc_dispatch(smcip->mci_mip,
2318 head, NULL, B_FALSE);
2319 mutex_enter(lock);
2320 }
2321 }
2322 if (mac_srs->srs_type & SRST_BW_CONTROL) {
2323 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
2324 mac_srs->srs_bw->mac_bw_polled += sz;
2325 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2326 }
2327 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, head, tail,
2328 count, sz);
2329 if (count <= 10)
2330 srs_rx->sr_stat.mrs_chaincntundr10++;
2331 else if (count > 10 && count <= 50)
2332 srs_rx->sr_stat.mrs_chaincnt10to50++;
2333 else
2334 srs_rx->sr_stat.mrs_chaincntover50++;
2335 }
2336
2337 /*
2338 * We are guaranteed that SRS_PROC will be set if we
2339 * are here. Also, poll thread gets to run only if
2340 * the drain was being done by a worker thread although
2341 * its possible that worker thread is still running
2342 * and poll thread was sent down to keep the pipeline
2343 * going instead of doing a complete drain and then
2344 * trying to poll the NIC.
2345 *
2346 * So we need to check SRS_WORKER flag to make sure
2347 * that the worker thread is not processing the queue
2348 * in parallel to us. The flags and conditions are
2349 * protected by the srs_lock to prevent any race. We
2350 * ensure that we don't drop the srs_lock from now
2351 * till the end and similarly we don't drop the srs_lock
2352 * in mac_rx_srs_drain() till similar condition check
2353 * are complete. The mac_rx_srs_drain() needs to ensure
2354 * that SRS_WORKER flag remains set as long as its
2355 * processing the queue.
2356 */
2357 if (!(mac_srs->srs_state & SRS_WORKER) &&
2358 (mac_srs->srs_first != NULL)) {
2359 /*
2360 * We have packets to process and worker thread
2361 * is not running. Check to see if poll thread is
2362 * allowed to process.
2363 */
2364 if (mac_srs->srs_state & SRS_LATENCY_OPT) {
2365 mac_srs->srs_drain_func(mac_srs, SRS_POLL_PROC);
2366 if (!(mac_srs->srs_state & SRS_PAUSE) &&
2367 srs_rx->sr_poll_pkt_cnt <=
2368 srs_rx->sr_lowat) {
2369 srs_rx->sr_poll_again++;
2370 goto check_again;
2371 }
2372 /*
2373 * We are already above low water mark
2374 * so stay in the polling mode but no
2375 * need to poll. Once we dip below
2376 * the polling threshold, the processing
2377 * thread (soft ring) will signal us
2378 * to poll again (MAC_UPDATE_SRS_COUNT)
2379 */
2380 srs_rx->sr_poll_drain_no_poll++;
2381 mac_srs->srs_state &= ~(SRS_PROC|SRS_GET_PKTS);
2382 /*
2383 * In B/W control case, its possible
2384 * that the backlog built up due to
2385 * B/W limit being reached and packets
2386 * are queued only in SRS. In this case,
2387 * we should schedule worker thread
2388 * since no one else will wake us up.
2389 */
2390 if ((mac_srs->srs_type & SRST_BW_CONTROL) &&
2391 (mac_srs->srs_tid == NULL)) {
2392 mac_srs->srs_tid =
2393 timeout(mac_srs_fire, mac_srs, 1);
2394 srs_rx->sr_poll_worker_wakeup++;
2395 }
2396 } else {
2397 /*
2398 * Wakeup the worker thread for more processing.
2399 * We optimize for throughput in this case.
2400 */
2401 mac_srs->srs_state &= ~(SRS_PROC|SRS_GET_PKTS);
2402 MAC_SRS_WORKER_WAKEUP(mac_srs);
2403 srs_rx->sr_poll_sig_worker++;
2404 }
2405 } else if ((mac_srs->srs_first == NULL) &&
2406 !(mac_srs->srs_state & SRS_WORKER)) {
2407 /*
2408 * There is nothing queued in SRS and
2409 * no worker thread running. Plus we
2410 * didn't get anything from the H/W
2411 * as well (head == NULL);
2412 */
2413 ASSERT(head == NULL);
2414 mac_srs->srs_state &=
2415 ~(SRS_PROC|SRS_GET_PKTS);
2416
2417 /*
2418 * If we have a packets in soft ring, don't allow
2419 * more packets to come into this SRS by keeping the
2420 * interrupts off but not polling the H/W. The
2421 * poll thread will get signaled as soon as
2422 * srs_poll_pkt_cnt dips below poll threshold.
2423 */
2424 if (srs_rx->sr_poll_pkt_cnt == 0) {
2425 srs_rx->sr_poll_intr_enable++;
2426 MAC_SRS_POLLING_OFF(mac_srs);
2427 } else {
2428 /*
2429 * We know nothing is queued in SRS
2430 * since we are here after checking
2431 * srs_first is NULL. The backlog
2432 * is entirely due to packets queued
2433 * in Soft ring which will wake us up
2434 * and get the interface out of polling
2435 * mode once the backlog dips below
2436 * sr_poll_thres.
2437 */
2438 srs_rx->sr_poll_no_poll++;
2439 }
2440 } else {
2441 /*
2442 * Worker thread is already running.
2443 * Nothing much to do. If the polling
2444 * was enabled, worker thread will deal
2445 * with that.
2446 */
2447 mac_srs->srs_state &= ~SRS_GET_PKTS;
2448 srs_rx->sr_poll_goto_sleep++;
2449 }
2450 }
2451 done:
2452 mac_srs->srs_state |= SRS_POLL_THR_QUIESCED;
2453 cv_signal(&mac_srs->srs_async);
2454 /*
2455 * If this is a temporary quiesce then wait for the restart signal
2456 * from the srs worker. Then clear the flags and signal the srs worker
2457 * to ensure a positive handshake and go back to start.
2458 */
2459 while (!(mac_srs->srs_state & (SRS_CONDEMNED | SRS_POLL_THR_RESTART)))
2460 cv_wait(async, lock);
2461 if (mac_srs->srs_state & SRS_POLL_THR_RESTART) {
2462 ASSERT(!(mac_srs->srs_state & SRS_CONDEMNED));
2463 mac_srs->srs_state &=
2464 ~(SRS_POLL_THR_QUIESCED | SRS_POLL_THR_RESTART);
2465 cv_signal(&mac_srs->srs_async);
2466 goto start;
2467 } else {
2468 mac_srs->srs_state |= SRS_POLL_THR_EXITED;
2469 cv_signal(&mac_srs->srs_async);
2470 CALLB_CPR_EXIT(&cprinfo);
2471 thread_exit();
2472 }
2473 }
2474
2475 /*
2476 * mac_srs_pick_chain
2477 *
2478 * In Bandwidth control case, checks how many packets can be processed
2479 * and return them in a sub chain.
2480 */
2481 static mblk_t *
mac_srs_pick_chain(mac_soft_ring_set_t * mac_srs,mblk_t ** chain_tail,size_t * chain_sz,int * chain_cnt)2482 mac_srs_pick_chain(mac_soft_ring_set_t *mac_srs, mblk_t **chain_tail,
2483 size_t *chain_sz, int *chain_cnt)
2484 {
2485 mblk_t *head = NULL;
2486 mblk_t *tail = NULL;
2487 size_t sz;
2488 size_t tsz = 0;
2489 int cnt = 0;
2490 mblk_t *mp;
2491
2492 ASSERT(MUTEX_HELD(&mac_srs->srs_lock));
2493 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
2494 if (((mac_srs->srs_bw->mac_bw_used + mac_srs->srs_size) <=
2495 mac_srs->srs_bw->mac_bw_limit) ||
2496 (mac_srs->srs_bw->mac_bw_limit == 0)) {
2497 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2498 head = mac_srs->srs_first;
2499 mac_srs->srs_first = NULL;
2500 *chain_tail = mac_srs->srs_last;
2501 mac_srs->srs_last = NULL;
2502 *chain_sz = mac_srs->srs_size;
2503 *chain_cnt = mac_srs->srs_count;
2504 mac_srs->srs_count = 0;
2505 mac_srs->srs_size = 0;
2506 return (head);
2507 }
2508
2509 /*
2510 * Can't clear the entire backlog.
2511 * Need to find how many packets to pick
2512 */
2513 ASSERT(MUTEX_HELD(&mac_srs->srs_bw->mac_bw_lock));
2514 while ((mp = mac_srs->srs_first) != NULL) {
2515 sz = msgdsize(mp);
2516 if ((tsz + sz + mac_srs->srs_bw->mac_bw_used) >
2517 mac_srs->srs_bw->mac_bw_limit) {
2518 if (!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED))
2519 mac_srs->srs_bw->mac_bw_state |=
2520 SRS_BW_ENFORCED;
2521 break;
2522 }
2523
2524 /*
2525 * The _size & cnt is decremented from the softrings
2526 * when they send up the packet for polling to work
2527 * properly.
2528 */
2529 tsz += sz;
2530 cnt++;
2531 mac_srs->srs_count--;
2532 mac_srs->srs_size -= sz;
2533 if (tail != NULL)
2534 tail->b_next = mp;
2535 else
2536 head = mp;
2537 tail = mp;
2538 mac_srs->srs_first = mac_srs->srs_first->b_next;
2539 }
2540 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2541 if (mac_srs->srs_first == NULL)
2542 mac_srs->srs_last = NULL;
2543
2544 if (tail != NULL)
2545 tail->b_next = NULL;
2546 *chain_tail = tail;
2547 *chain_cnt = cnt;
2548 *chain_sz = tsz;
2549
2550 return (head);
2551 }
2552
2553 /*
2554 * mac_rx_srs_drain
2555 *
2556 * The SRS drain routine. Gets to run to clear the queue. Any thread
2557 * (worker, interrupt, poll) can call this based on processing model.
2558 * The first thing we do is disable interrupts if possible and then
2559 * drain the queue. we also try to poll the underlying hardware if
2560 * there is a dedicated hardware Rx ring assigned to this SRS.
2561 *
2562 * There is a equivalent drain routine in bandwidth control mode
2563 * mac_rx_srs_drain_bw. There is some code duplication between the two
2564 * routines but they are highly performance sensitive and are easier
2565 * to read/debug if they stay separate. Any code changes here might
2566 * also apply to mac_rx_srs_drain_bw as well.
2567 */
2568 void
mac_rx_srs_drain(mac_soft_ring_set_t * mac_srs,uint_t proc_type)2569 mac_rx_srs_drain(mac_soft_ring_set_t *mac_srs, uint_t proc_type)
2570 {
2571 mblk_t *head;
2572 mblk_t *tail;
2573 timeout_id_t tid;
2574 int cnt = 0;
2575 mac_client_impl_t *mcip = mac_srs->srs_mcip;
2576 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx;
2577
2578 ASSERT(MUTEX_HELD(&mac_srs->srs_lock));
2579 ASSERT(!(mac_srs->srs_type & SRST_BW_CONTROL));
2580
2581 /* If we are blanked i.e. can't do upcalls, then we are done */
2582 if (mac_srs->srs_state & (SRS_BLANK | SRS_PAUSE)) {
2583 ASSERT((mac_srs->srs_type & SRST_NO_SOFT_RINGS) ||
2584 (mac_srs->srs_state & SRS_PAUSE));
2585 goto out;
2586 }
2587
2588 if (mac_srs->srs_first == NULL)
2589 goto out;
2590
2591 if (!(mac_srs->srs_state & SRS_LATENCY_OPT) &&
2592 (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat)) {
2593 /*
2594 * In the normal case, the SRS worker thread does no
2595 * work and we wait for a backlog to build up before
2596 * we switch into polling mode. In case we are
2597 * optimizing for throughput, we use the worker thread
2598 * as well. The goal is to let worker thread process
2599 * the queue and poll thread to feed packets into
2600 * the queue. As such, we should signal the poll
2601 * thread to try and get more packets.
2602 *
2603 * We could have pulled this check in the POLL_RING
2604 * macro itself but keeping it explicit here makes
2605 * the architecture more human understandable.
2606 */
2607 MAC_SRS_POLL_RING(mac_srs);
2608 }
2609
2610 again:
2611 head = mac_srs->srs_first;
2612 mac_srs->srs_first = NULL;
2613 tail = mac_srs->srs_last;
2614 mac_srs->srs_last = NULL;
2615 cnt = mac_srs->srs_count;
2616 mac_srs->srs_count = 0;
2617
2618 ASSERT(head != NULL);
2619 ASSERT(tail != NULL);
2620
2621 if ((tid = mac_srs->srs_tid) != NULL)
2622 mac_srs->srs_tid = NULL;
2623
2624 mac_srs->srs_state |= (SRS_PROC|proc_type);
2625
2626 /*
2627 * mcip is NULL for broadcast and multicast flows. The promisc
2628 * callbacks for broadcast and multicast packets are delivered from
2629 * mac_rx() and we don't need to worry about that case in this path
2630 */
2631 if (mcip != NULL) {
2632 if (mcip->mci_promisc_list != NULL) {
2633 mutex_exit(&mac_srs->srs_lock);
2634 mac_promisc_client_dispatch(mcip, head);
2635 mutex_enter(&mac_srs->srs_lock);
2636 }
2637 if (MAC_PROTECT_ENABLED(mcip, MPT_IPNOSPOOF)) {
2638 mutex_exit(&mac_srs->srs_lock);
2639 mac_protect_intercept_dynamic(mcip, head);
2640 mutex_enter(&mac_srs->srs_lock);
2641 }
2642 }
2643
2644 /*
2645 * Check if SRS itself is doing the processing. This direct
2646 * path applies only when subflows are present.
2647 */
2648 if (mac_srs->srs_type & SRST_NO_SOFT_RINGS) {
2649 mac_direct_rx_t proc;
2650 void *arg1;
2651 mac_resource_handle_t arg2;
2652
2653 /*
2654 * This is the case when a Rx is directly
2655 * assigned and we have a fully classified
2656 * protocol chain. We can deal with it in
2657 * one shot.
2658 */
2659 proc = srs_rx->sr_func;
2660 arg1 = srs_rx->sr_arg1;
2661 arg2 = srs_rx->sr_arg2;
2662
2663 mac_srs->srs_state |= SRS_CLIENT_PROC;
2664 mutex_exit(&mac_srs->srs_lock);
2665 if (tid != NULL) {
2666 (void) untimeout(tid);
2667 tid = NULL;
2668 }
2669
2670 proc(arg1, arg2, head, NULL);
2671 /*
2672 * Decrement the size and count here itelf
2673 * since the packet has been processed.
2674 */
2675 mutex_enter(&mac_srs->srs_lock);
2676 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt);
2677 if (mac_srs->srs_state & SRS_CLIENT_WAIT)
2678 cv_signal(&mac_srs->srs_client_cv);
2679 mac_srs->srs_state &= ~SRS_CLIENT_PROC;
2680 } else {
2681 /* Some kind of softrings based fanout is required */
2682 mutex_exit(&mac_srs->srs_lock);
2683 if (tid != NULL) {
2684 (void) untimeout(tid);
2685 tid = NULL;
2686 }
2687
2688 /*
2689 * Since the fanout routines can deal with chains,
2690 * shoot the entire chain up.
2691 */
2692 if (mac_srs->srs_type & SRST_FANOUT_SRC_IP)
2693 mac_rx_srs_fanout(mac_srs, head);
2694 else
2695 mac_rx_srs_proto_fanout(mac_srs, head);
2696 mutex_enter(&mac_srs->srs_lock);
2697 }
2698
2699 if (!(mac_srs->srs_state & (SRS_BLANK|SRS_PAUSE)) &&
2700 (mac_srs->srs_first != NULL)) {
2701 /*
2702 * More packets arrived while we were clearing the
2703 * SRS. This can be possible because of one of
2704 * three conditions below:
2705 * 1) The driver is using multiple worker threads
2706 * to send the packets to us.
2707 * 2) The driver has a race in switching
2708 * between interrupt and polling mode or
2709 * 3) Packets are arriving in this SRS via the
2710 * S/W classification as well.
2711 *
2712 * We should switch to polling mode and see if we
2713 * need to send the poll thread down. Also, signal
2714 * the worker thread to process whats just arrived.
2715 */
2716 MAC_SRS_POLLING_ON(mac_srs);
2717 if (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat) {
2718 srs_rx->sr_drain_poll_sig++;
2719 MAC_SRS_POLL_RING(mac_srs);
2720 }
2721
2722 /*
2723 * If we didn't signal the poll thread, we need
2724 * to deal with the pending packets ourselves.
2725 */
2726 if (proc_type == SRS_WORKER) {
2727 srs_rx->sr_drain_again++;
2728 goto again;
2729 } else {
2730 srs_rx->sr_drain_worker_sig++;
2731 cv_signal(&mac_srs->srs_async);
2732 }
2733 }
2734
2735 out:
2736 if (mac_srs->srs_state & SRS_GET_PKTS) {
2737 /*
2738 * Poll thread is already running. Leave the
2739 * SRS_RPOC set and hand over the control to
2740 * poll thread.
2741 */
2742 mac_srs->srs_state &= ~proc_type;
2743 srs_rx->sr_drain_poll_running++;
2744 return;
2745 }
2746
2747 /*
2748 * Even if there are no packets queued in SRS, we
2749 * need to make sure that the shared counter is
2750 * clear and any associated softrings have cleared
2751 * all the backlog. Otherwise, leave the interface
2752 * in polling mode and the poll thread will get
2753 * signalled once the count goes down to zero.
2754 *
2755 * If someone is already draining the queue (SRS_PROC is
2756 * set) when the srs_poll_pkt_cnt goes down to zero,
2757 * then it means that drain is already running and we
2758 * will turn off polling at that time if there is
2759 * no backlog.
2760 *
2761 * As long as there are packets queued either
2762 * in soft ring set or its soft rings, we will leave
2763 * the interface in polling mode (even if the drain
2764 * was done being the interrupt thread). We signal
2765 * the poll thread as well if we have dipped below
2766 * low water mark.
2767 *
2768 * NOTE: We can't use the MAC_SRS_POLLING_ON macro
2769 * since that turn polling on only for worker thread.
2770 * Its not worth turning polling on for interrupt
2771 * thread (since NIC will not issue another interrupt)
2772 * unless a backlog builds up.
2773 */
2774 if ((srs_rx->sr_poll_pkt_cnt > 0) &&
2775 (mac_srs->srs_state & SRS_POLLING_CAPAB)) {
2776 mac_srs->srs_state &= ~(SRS_PROC|proc_type);
2777 srs_rx->sr_drain_keep_polling++;
2778 MAC_SRS_POLLING_ON(mac_srs);
2779 if (srs_rx->sr_poll_pkt_cnt <= srs_rx->sr_lowat)
2780 MAC_SRS_POLL_RING(mac_srs);
2781 return;
2782 }
2783
2784 /* Nothing else to do. Get out of poll mode */
2785 MAC_SRS_POLLING_OFF(mac_srs);
2786 mac_srs->srs_state &= ~(SRS_PROC|proc_type);
2787 srs_rx->sr_drain_finish_intr++;
2788 }
2789
2790 /*
2791 * mac_rx_srs_drain_bw
2792 *
2793 * The SRS BW drain routine. Gets to run to clear the queue. Any thread
2794 * (worker, interrupt, poll) can call this based on processing model.
2795 * The first thing we do is disable interrupts if possible and then
2796 * drain the queue. we also try to poll the underlying hardware if
2797 * there is a dedicated hardware Rx ring assigned to this SRS.
2798 *
2799 * There is a equivalent drain routine in non bandwidth control mode
2800 * mac_rx_srs_drain. There is some code duplication between the two
2801 * routines but they are highly performance sensitive and are easier
2802 * to read/debug if they stay separate. Any code changes here might
2803 * also apply to mac_rx_srs_drain as well.
2804 */
2805 void
mac_rx_srs_drain_bw(mac_soft_ring_set_t * mac_srs,uint_t proc_type)2806 mac_rx_srs_drain_bw(mac_soft_ring_set_t *mac_srs, uint_t proc_type)
2807 {
2808 mblk_t *head;
2809 mblk_t *tail;
2810 timeout_id_t tid;
2811 size_t sz = 0;
2812 int cnt = 0;
2813 mac_client_impl_t *mcip = mac_srs->srs_mcip;
2814 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx;
2815 clock_t now;
2816
2817 ASSERT(MUTEX_HELD(&mac_srs->srs_lock));
2818 ASSERT(mac_srs->srs_type & SRST_BW_CONTROL);
2819 again:
2820 /* Check if we are doing B/W control */
2821 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
2822 now = ddi_get_lbolt();
2823 if (mac_srs->srs_bw->mac_bw_curr_time != now) {
2824 mac_srs->srs_bw->mac_bw_curr_time = now;
2825 mac_srs->srs_bw->mac_bw_used = 0;
2826 if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)
2827 mac_srs->srs_bw->mac_bw_state &= ~SRS_BW_ENFORCED;
2828 } else if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) {
2829 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2830 goto done;
2831 } else if (mac_srs->srs_bw->mac_bw_used >
2832 mac_srs->srs_bw->mac_bw_limit) {
2833 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED;
2834 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2835 goto done;
2836 }
2837 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2838
2839 /* If we are blanked i.e. can't do upcalls, then we are done */
2840 if (mac_srs->srs_state & (SRS_BLANK | SRS_PAUSE)) {
2841 ASSERT((mac_srs->srs_type & SRST_NO_SOFT_RINGS) ||
2842 (mac_srs->srs_state & SRS_PAUSE));
2843 goto done;
2844 }
2845
2846 sz = 0;
2847 cnt = 0;
2848 if ((head = mac_srs_pick_chain(mac_srs, &tail, &sz, &cnt)) == NULL) {
2849 /*
2850 * We couldn't pick up a single packet.
2851 */
2852 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
2853 if ((mac_srs->srs_bw->mac_bw_used == 0) &&
2854 (mac_srs->srs_size != 0) &&
2855 !(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) {
2856 /*
2857 * Seems like configured B/W doesn't
2858 * even allow processing of 1 packet
2859 * per tick.
2860 *
2861 * XXX: raise the limit to processing
2862 * at least 1 packet per tick.
2863 */
2864 mac_srs->srs_bw->mac_bw_limit +=
2865 mac_srs->srs_bw->mac_bw_limit;
2866 mac_srs->srs_bw->mac_bw_drop_threshold +=
2867 mac_srs->srs_bw->mac_bw_drop_threshold;
2868 cmn_err(CE_NOTE, "mac_rx_srs_drain: srs(%p) "
2869 "raised B/W limit to %d since not even a "
2870 "single packet can be processed per "
2871 "tick %d\n", (void *)mac_srs,
2872 (int)mac_srs->srs_bw->mac_bw_limit,
2873 (int)msgdsize(mac_srs->srs_first));
2874 }
2875 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2876 goto done;
2877 }
2878
2879 ASSERT(head != NULL);
2880 ASSERT(tail != NULL);
2881
2882 /* zero bandwidth: drop all and return to interrupt mode */
2883 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
2884 if (mac_srs->srs_bw->mac_bw_limit == 0) {
2885 srs_rx->sr_stat.mrs_sdrops += cnt;
2886 ASSERT(mac_srs->srs_bw->mac_bw_sz >= sz);
2887 mac_srs->srs_bw->mac_bw_sz -= sz;
2888 mac_srs->srs_bw->mac_bw_drop_bytes += sz;
2889 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2890 mac_drop_chain(head, "Rx no bandwidth");
2891 goto leave_poll;
2892 } else {
2893 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
2894 }
2895
2896 if ((tid = mac_srs->srs_tid) != NULL)
2897 mac_srs->srs_tid = NULL;
2898
2899 mac_srs->srs_state |= (SRS_PROC|proc_type);
2900 MAC_SRS_WORKER_POLLING_ON(mac_srs);
2901
2902 /*
2903 * mcip is NULL for broadcast and multicast flows. The promisc
2904 * callbacks for broadcast and multicast packets are delivered from
2905 * mac_rx() and we don't need to worry about that case in this path
2906 */
2907 if (mcip != NULL) {
2908 if (mcip->mci_promisc_list != NULL) {
2909 mutex_exit(&mac_srs->srs_lock);
2910 mac_promisc_client_dispatch(mcip, head);
2911 mutex_enter(&mac_srs->srs_lock);
2912 }
2913 if (MAC_PROTECT_ENABLED(mcip, MPT_IPNOSPOOF)) {
2914 mutex_exit(&mac_srs->srs_lock);
2915 mac_protect_intercept_dynamic(mcip, head);
2916 mutex_enter(&mac_srs->srs_lock);
2917 }
2918 }
2919
2920 /*
2921 * Check if SRS itself is doing the processing
2922 * This direct path does not apply when subflows are present. In this
2923 * case, packets need to be dispatched to a soft ring according to the
2924 * flow's bandwidth and other resources contraints.
2925 */
2926 if (mac_srs->srs_type & SRST_NO_SOFT_RINGS) {
2927 mac_direct_rx_t proc;
2928 void *arg1;
2929 mac_resource_handle_t arg2;
2930
2931 /*
2932 * This is the case when a Rx is directly
2933 * assigned and we have a fully classified
2934 * protocol chain. We can deal with it in
2935 * one shot.
2936 */
2937 proc = srs_rx->sr_func;
2938 arg1 = srs_rx->sr_arg1;
2939 arg2 = srs_rx->sr_arg2;
2940
2941 mac_srs->srs_state |= SRS_CLIENT_PROC;
2942 mutex_exit(&mac_srs->srs_lock);
2943 if (tid != NULL) {
2944 (void) untimeout(tid);
2945 tid = NULL;
2946 }
2947
2948 proc(arg1, arg2, head, NULL);
2949 /*
2950 * Decrement the size and count here itelf
2951 * since the packet has been processed.
2952 */
2953 mutex_enter(&mac_srs->srs_lock);
2954 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt);
2955 MAC_UPDATE_SRS_SIZE_LOCKED(mac_srs, sz);
2956
2957 if (mac_srs->srs_state & SRS_CLIENT_WAIT)
2958 cv_signal(&mac_srs->srs_client_cv);
2959 mac_srs->srs_state &= ~SRS_CLIENT_PROC;
2960 } else {
2961 /* Some kind of softrings based fanout is required */
2962 mutex_exit(&mac_srs->srs_lock);
2963 if (tid != NULL) {
2964 (void) untimeout(tid);
2965 tid = NULL;
2966 }
2967
2968 /*
2969 * Since the fanout routines can deal with chains,
2970 * shoot the entire chain up.
2971 */
2972 if (mac_srs->srs_type & SRST_FANOUT_SRC_IP)
2973 mac_rx_srs_fanout(mac_srs, head);
2974 else
2975 mac_rx_srs_proto_fanout(mac_srs, head);
2976 mutex_enter(&mac_srs->srs_lock);
2977 }
2978
2979 /*
2980 * Send the poll thread to pick up any packets arrived
2981 * so far. This also serves as the last check in case
2982 * nothing else is queued in the SRS. The poll thread
2983 * is signalled only in the case the drain was done
2984 * by the worker thread and SRS_WORKER is set. The
2985 * worker thread can run in parallel as long as the
2986 * SRS_WORKER flag is set. We we have nothing else to
2987 * process, we can exit while leaving SRS_PROC set
2988 * which gives the poll thread control to process and
2989 * cleanup once it returns from the NIC.
2990 *
2991 * If we have nothing else to process, we need to
2992 * ensure that we keep holding the srs_lock till
2993 * all the checks below are done and control is
2994 * handed to the poll thread if it was running.
2995 */
2996 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
2997 if (!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) {
2998 if (mac_srs->srs_first != NULL) {
2999 if (proc_type == SRS_WORKER) {
3000 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
3001 if (srs_rx->sr_poll_pkt_cnt <=
3002 srs_rx->sr_lowat)
3003 MAC_SRS_POLL_RING(mac_srs);
3004 goto again;
3005 } else {
3006 cv_signal(&mac_srs->srs_async);
3007 }
3008 }
3009 }
3010 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
3011
3012 done:
3013
3014 if (mac_srs->srs_state & SRS_GET_PKTS) {
3015 /*
3016 * Poll thread is already running. Leave the
3017 * SRS_RPOC set and hand over the control to
3018 * poll thread.
3019 */
3020 mac_srs->srs_state &= ~proc_type;
3021 return;
3022 }
3023
3024 /*
3025 * If we can't process packets because we have exceeded
3026 * B/W limit for this tick, just set the timeout
3027 * and leave.
3028 *
3029 * Even if there are no packets queued in SRS, we
3030 * need to make sure that the shared counter is
3031 * clear and any associated softrings have cleared
3032 * all the backlog. Otherwise, leave the interface
3033 * in polling mode and the poll thread will get
3034 * signalled once the count goes down to zero.
3035 *
3036 * If someone is already draining the queue (SRS_PROC is
3037 * set) when the srs_poll_pkt_cnt goes down to zero,
3038 * then it means that drain is already running and we
3039 * will turn off polling at that time if there is
3040 * no backlog. As long as there are packets queued either
3041 * is soft ring set or its soft rings, we will leave
3042 * the interface in polling mode.
3043 */
3044 mutex_enter(&mac_srs->srs_bw->mac_bw_lock);
3045 if ((mac_srs->srs_state & SRS_POLLING_CAPAB) &&
3046 ((mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED) ||
3047 (srs_rx->sr_poll_pkt_cnt > 0))) {
3048 MAC_SRS_POLLING_ON(mac_srs);
3049 mac_srs->srs_state &= ~(SRS_PROC|proc_type);
3050 if ((mac_srs->srs_first != NULL) &&
3051 (mac_srs->srs_tid == NULL))
3052 mac_srs->srs_tid = timeout(mac_srs_fire,
3053 mac_srs, 1);
3054 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
3055 return;
3056 }
3057 mutex_exit(&mac_srs->srs_bw->mac_bw_lock);
3058
3059 leave_poll:
3060
3061 /* Nothing else to do. Get out of poll mode */
3062 MAC_SRS_POLLING_OFF(mac_srs);
3063 mac_srs->srs_state &= ~(SRS_PROC|proc_type);
3064 }
3065
3066 /*
3067 * mac_srs_worker
3068 *
3069 * The SRS worker routine. Drains the queue when no one else is
3070 * processing it.
3071 */
3072 void
mac_srs_worker(mac_soft_ring_set_t * mac_srs)3073 mac_srs_worker(mac_soft_ring_set_t *mac_srs)
3074 {
3075 kmutex_t *lock = &mac_srs->srs_lock;
3076 kcondvar_t *async = &mac_srs->srs_async;
3077 callb_cpr_t cprinfo;
3078 boolean_t bw_ctl_flag;
3079
3080 CALLB_CPR_INIT(&cprinfo, lock, callb_generic_cpr, "srs_worker");
3081 mutex_enter(lock);
3082
3083 start:
3084 for (;;) {
3085 bw_ctl_flag = B_FALSE;
3086 if (mac_srs->srs_type & SRST_BW_CONTROL) {
3087 MAC_SRS_BW_LOCK(mac_srs);
3088 MAC_SRS_CHECK_BW_CONTROL(mac_srs);
3089 if (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)
3090 bw_ctl_flag = B_TRUE;
3091 MAC_SRS_BW_UNLOCK(mac_srs);
3092 }
3093 /*
3094 * The SRS_BW_ENFORCED flag may change since we have dropped
3095 * the mac_bw_lock. However the drain function can handle both
3096 * a drainable SRS or a bandwidth controlled SRS, and the
3097 * effect of scheduling a timeout is to wakeup the worker
3098 * thread which in turn will call the drain function. Since
3099 * we release the srs_lock atomically only in the cv_wait there
3100 * isn't a fear of waiting for ever.
3101 */
3102 while (((mac_srs->srs_state & SRS_PROC) ||
3103 (mac_srs->srs_first == NULL) || bw_ctl_flag ||
3104 (mac_srs->srs_state & SRS_TX_BLOCKED)) &&
3105 !(mac_srs->srs_state & SRS_PAUSE)) {
3106 /*
3107 * If we have packets queued and we are here
3108 * because B/W control is in place, we better
3109 * schedule the worker wakeup after 1 tick
3110 * to see if bandwidth control can be relaxed.
3111 */
3112 if (bw_ctl_flag && mac_srs->srs_tid == NULL) {
3113 /*
3114 * We need to ensure that a timer is already
3115 * scheduled or we force schedule one for
3116 * later so that we can continue processing
3117 * after this quanta is over.
3118 */
3119 mac_srs->srs_tid = timeout(mac_srs_fire,
3120 mac_srs, 1);
3121 }
3122 wait:
3123 CALLB_CPR_SAFE_BEGIN(&cprinfo);
3124 cv_wait(async, lock);
3125 CALLB_CPR_SAFE_END(&cprinfo, lock);
3126
3127 if (mac_srs->srs_state & SRS_PAUSE)
3128 goto done;
3129 if (mac_srs->srs_state & SRS_PROC)
3130 goto wait;
3131
3132 if (mac_srs->srs_first != NULL &&
3133 mac_srs->srs_type & SRST_BW_CONTROL) {
3134 MAC_SRS_BW_LOCK(mac_srs);
3135 if (mac_srs->srs_bw->mac_bw_state &
3136 SRS_BW_ENFORCED) {
3137 MAC_SRS_CHECK_BW_CONTROL(mac_srs);
3138 }
3139 bw_ctl_flag = mac_srs->srs_bw->mac_bw_state &
3140 SRS_BW_ENFORCED;
3141 MAC_SRS_BW_UNLOCK(mac_srs);
3142 }
3143 }
3144
3145 if (mac_srs->srs_state & SRS_PAUSE)
3146 goto done;
3147 mac_srs->srs_drain_func(mac_srs, SRS_WORKER);
3148 }
3149 done:
3150 /*
3151 * The Rx SRS quiesce logic first cuts off packet supply to the SRS
3152 * from both hard and soft classifications and waits for such threads
3153 * to finish before signaling the worker. So at this point the only
3154 * thread left that could be competing with the worker is the poll
3155 * thread. In the case of Tx, there shouldn't be any thread holding
3156 * SRS_PROC at this point.
3157 */
3158 if (!(mac_srs->srs_state & SRS_PROC)) {
3159 mac_srs->srs_state |= SRS_PROC;
3160 } else {
3161 ASSERT((mac_srs->srs_type & SRST_TX) == 0);
3162 /*
3163 * Poll thread still owns the SRS and is still running
3164 */
3165 ASSERT((mac_srs->srs_poll_thr == NULL) ||
3166 ((mac_srs->srs_state & SRS_POLL_THR_OWNER) ==
3167 SRS_POLL_THR_OWNER));
3168 }
3169 mac_srs_worker_quiesce(mac_srs);
3170 /*
3171 * Wait for the SRS_RESTART or SRS_CONDEMNED signal from the initiator
3172 * of the quiesce operation
3173 */
3174 while (!(mac_srs->srs_state & (SRS_CONDEMNED | SRS_RESTART)))
3175 cv_wait(&mac_srs->srs_async, &mac_srs->srs_lock);
3176
3177 if (mac_srs->srs_state & SRS_RESTART) {
3178 ASSERT(!(mac_srs->srs_state & SRS_CONDEMNED));
3179 mac_srs_worker_restart(mac_srs);
3180 mac_srs->srs_state &= ~SRS_PROC;
3181 goto start;
3182 }
3183
3184 if (!(mac_srs->srs_state & SRS_CONDEMNED_DONE))
3185 mac_srs_worker_quiesce(mac_srs);
3186
3187 mac_srs->srs_state &= ~SRS_PROC;
3188 /* The macro drops the srs_lock */
3189 CALLB_CPR_EXIT(&cprinfo);
3190 thread_exit();
3191 }
3192
3193 /*
3194 * mac_rx_srs_subflow_process
3195 *
3196 * Receive side routine called from interrupt path when there are
3197 * sub flows present on this SRS.
3198 */
3199 /* ARGSUSED */
3200 void
mac_rx_srs_subflow_process(void * arg,mac_resource_handle_t srs,mblk_t * mp_chain,boolean_t loopback)3201 mac_rx_srs_subflow_process(void *arg, mac_resource_handle_t srs,
3202 mblk_t *mp_chain, boolean_t loopback)
3203 {
3204 flow_entry_t *flent = NULL;
3205 flow_entry_t *prev_flent = NULL;
3206 mblk_t *mp = NULL;
3207 mblk_t *tail = NULL;
3208 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)srs;
3209 mac_client_impl_t *mcip;
3210
3211 mcip = mac_srs->srs_mcip;
3212 ASSERT(mcip != NULL);
3213
3214 /*
3215 * We need to determine the SRS for every packet
3216 * by walking the flow table, if we don't get any,
3217 * then we proceed using the SRS we came with.
3218 */
3219 mp = tail = mp_chain;
3220 while (mp != NULL) {
3221
3222 /*
3223 * We will increment the stats for the mactching subflow.
3224 * when we get the bytes/pkt count for the classified packets
3225 * later in mac_rx_srs_process.
3226 */
3227 (void) mac_flow_lookup(mcip->mci_subflow_tab, mp,
3228 FLOW_INBOUND, &flent);
3229
3230 if (mp == mp_chain || flent == prev_flent) {
3231 if (prev_flent != NULL)
3232 FLOW_REFRELE(prev_flent);
3233 prev_flent = flent;
3234 flent = NULL;
3235 tail = mp;
3236 mp = mp->b_next;
3237 continue;
3238 }
3239 tail->b_next = NULL;
3240 /*
3241 * A null indicates, this is for the mac_srs itself.
3242 * XXX-venu : probably assert for fe_rx_srs_cnt == 0.
3243 */
3244 if (prev_flent == NULL || prev_flent->fe_rx_srs_cnt == 0) {
3245 mac_rx_srs_process(arg,
3246 (mac_resource_handle_t)mac_srs, mp_chain,
3247 loopback);
3248 } else {
3249 (prev_flent->fe_cb_fn)(prev_flent->fe_cb_arg1,
3250 prev_flent->fe_cb_arg2, mp_chain, loopback);
3251 FLOW_REFRELE(prev_flent);
3252 }
3253 prev_flent = flent;
3254 flent = NULL;
3255 mp_chain = mp;
3256 tail = mp;
3257 mp = mp->b_next;
3258 }
3259 /* Last chain */
3260 ASSERT(mp_chain != NULL);
3261 if (prev_flent == NULL || prev_flent->fe_rx_srs_cnt == 0) {
3262 mac_rx_srs_process(arg,
3263 (mac_resource_handle_t)mac_srs, mp_chain, loopback);
3264 } else {
3265 (prev_flent->fe_cb_fn)(prev_flent->fe_cb_arg1,
3266 prev_flent->fe_cb_arg2, mp_chain, loopback);
3267 FLOW_REFRELE(prev_flent);
3268 }
3269 }
3270
3271 /*
3272 * MAC SRS receive side routine. If the data is coming from the
3273 * network (i.e. from a NIC) then this is called in interrupt context.
3274 * If the data is coming from a local sender (e.g. mac_tx_send() or
3275 * bridge_forward()) then this is not called in interrupt context.
3276 *
3277 * loopback is set to force a context switch on the loopback
3278 * path between MAC clients.
3279 */
3280 /* ARGSUSED */
3281 void
mac_rx_srs_process(void * arg,mac_resource_handle_t srs,mblk_t * mp_chain,boolean_t loopback)3282 mac_rx_srs_process(void *arg, mac_resource_handle_t srs, mblk_t *mp_chain,
3283 boolean_t loopback)
3284 {
3285 mac_soft_ring_set_t *mac_srs = (mac_soft_ring_set_t *)srs;
3286 mblk_t *mp, *tail, *head;
3287 int count = 0;
3288 int count1;
3289 size_t sz = 0;
3290 size_t chain_sz, sz1;
3291 mac_bw_ctl_t *mac_bw;
3292 mac_srs_rx_t *srs_rx = &mac_srs->srs_rx;
3293
3294 /*
3295 * Set the tail, count and sz. We set the sz irrespective
3296 * of whether we are doing B/W control or not for the
3297 * purpose of updating the stats.
3298 */
3299 mp = tail = mp_chain;
3300 while (mp != NULL) {
3301 tail = mp;
3302 count++;
3303 sz += msgdsize(mp);
3304 mp = mp->b_next;
3305 }
3306
3307 mutex_enter(&mac_srs->srs_lock);
3308
3309 if (loopback) {
3310 SRS_RX_STAT_UPDATE(mac_srs, lclbytes, sz);
3311 SRS_RX_STAT_UPDATE(mac_srs, lclcnt, count);
3312
3313 } else {
3314 SRS_RX_STAT_UPDATE(mac_srs, intrbytes, sz);
3315 SRS_RX_STAT_UPDATE(mac_srs, intrcnt, count);
3316 }
3317
3318 /*
3319 * If the SRS in already being processed; has been blanked;
3320 * can be processed by worker thread only; or the B/W limit
3321 * has been reached, then queue the chain and check if
3322 * worker thread needs to be awakend.
3323 */
3324 if (mac_srs->srs_type & SRST_BW_CONTROL) {
3325 mac_bw = mac_srs->srs_bw;
3326 ASSERT(mac_bw != NULL);
3327 mutex_enter(&mac_bw->mac_bw_lock);
3328 mac_bw->mac_bw_intr += sz;
3329 if (mac_bw->mac_bw_limit == 0) {
3330 /* zero bandwidth: drop all */
3331 srs_rx->sr_stat.mrs_sdrops += count;
3332 mac_bw->mac_bw_drop_bytes += sz;
3333 mutex_exit(&mac_bw->mac_bw_lock);
3334 mutex_exit(&mac_srs->srs_lock);
3335 mac_drop_chain(mp_chain, "Rx no bandwidth");
3336 return;
3337 } else {
3338 if ((mac_bw->mac_bw_sz + sz) <=
3339 mac_bw->mac_bw_drop_threshold) {
3340 mutex_exit(&mac_bw->mac_bw_lock);
3341 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, mp_chain,
3342 tail, count, sz);
3343 } else {
3344 mp = mp_chain;
3345 chain_sz = 0;
3346 count1 = 0;
3347 tail = NULL;
3348 head = NULL;
3349 while (mp != NULL) {
3350 sz1 = msgdsize(mp);
3351 if (mac_bw->mac_bw_sz + chain_sz + sz1 >
3352 mac_bw->mac_bw_drop_threshold)
3353 break;
3354 chain_sz += sz1;
3355 count1++;
3356 tail = mp;
3357 mp = mp->b_next;
3358 }
3359 mutex_exit(&mac_bw->mac_bw_lock);
3360 if (tail != NULL) {
3361 head = tail->b_next;
3362 tail->b_next = NULL;
3363 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs,
3364 mp_chain, tail, count1, chain_sz);
3365 sz -= chain_sz;
3366 count -= count1;
3367 } else {
3368 /* Can't pick up any */
3369 head = mp_chain;
3370 }
3371 if (head != NULL) {
3372 /* Drop any packet over the threshold */
3373 srs_rx->sr_stat.mrs_sdrops += count;
3374 mutex_enter(&mac_bw->mac_bw_lock);
3375 mac_bw->mac_bw_drop_bytes += sz;
3376 mutex_exit(&mac_bw->mac_bw_lock);
3377 freemsgchain(head);
3378 }
3379 }
3380 MAC_SRS_WORKER_WAKEUP(mac_srs);
3381 mutex_exit(&mac_srs->srs_lock);
3382 return;
3383 }
3384 }
3385
3386 /*
3387 * If the total number of packets queued in the SRS and
3388 * its associated soft rings exceeds the max allowed,
3389 * then drop the chain. If we are polling capable, this
3390 * shouldn't be happening.
3391 */
3392 if (!(mac_srs->srs_type & SRST_BW_CONTROL) &&
3393 (srs_rx->sr_poll_pkt_cnt > srs_rx->sr_hiwat)) {
3394 mac_bw = mac_srs->srs_bw;
3395 srs_rx->sr_stat.mrs_sdrops += count;
3396 mutex_enter(&mac_bw->mac_bw_lock);
3397 mac_bw->mac_bw_drop_bytes += sz;
3398 mutex_exit(&mac_bw->mac_bw_lock);
3399 freemsgchain(mp_chain);
3400 mutex_exit(&mac_srs->srs_lock);
3401 return;
3402 }
3403
3404 MAC_RX_SRS_ENQUEUE_CHAIN(mac_srs, mp_chain, tail, count, sz);
3405
3406 if (!(mac_srs->srs_state & SRS_PROC)) {
3407 /*
3408 * If we are coming via loopback, if we are not optimizing for
3409 * latency, or if our stack is running deep, we should signal
3410 * the worker thread.
3411 */
3412 if (loopback || !(mac_srs->srs_state & SRS_LATENCY_OPT)) {
3413 /*
3414 * For loopback, We need to let the worker take
3415 * over as we don't want to continue in the same
3416 * thread even if we can. This could lead to stack
3417 * overflows and may also end up using
3418 * resources (cpu) incorrectly.
3419 */
3420 cv_signal(&mac_srs->srs_async);
3421 } else if (STACK_BIAS + (uintptr_t)getfp() -
3422 (uintptr_t)curthread->t_stkbase < mac_rx_srs_stack_needed) {
3423 if (++mac_rx_srs_stack_toodeep == 0)
3424 mac_rx_srs_stack_toodeep = 1;
3425 cv_signal(&mac_srs->srs_async);
3426 } else {
3427 /*
3428 * Seems like no one is processing the SRS and
3429 * there is no backlog. We also inline process
3430 * our packet if its a single packet in non
3431 * latency optimized case (in latency optimized
3432 * case, we inline process chains of any size).
3433 */
3434 mac_srs->srs_drain_func(mac_srs, SRS_PROC_FAST);
3435 }
3436 }
3437 mutex_exit(&mac_srs->srs_lock);
3438 }
3439
3440 /* TX SIDE ROUTINES (RUNTIME) */
3441
3442 /*
3443 * mac_tx_srs_no_desc
3444 *
3445 * This routine is called by Tx single ring default mode
3446 * when Tx ring runs out of descs.
3447 */
3448 mac_tx_cookie_t
mac_tx_srs_no_desc(mac_soft_ring_set_t * mac_srs,mblk_t * mp_chain,uint16_t flag,mblk_t ** ret_mp)3449 mac_tx_srs_no_desc(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain,
3450 uint16_t flag, mblk_t **ret_mp)
3451 {
3452 mac_tx_cookie_t cookie = 0;
3453 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx;
3454 boolean_t wakeup_worker = B_TRUE;
3455 uint32_t tx_mode = srs_tx->st_mode;
3456 int cnt, sz;
3457 mblk_t *tail;
3458
3459 ASSERT(tx_mode == SRS_TX_DEFAULT || tx_mode == SRS_TX_BW);
3460 if (flag & MAC_DROP_ON_NO_DESC) {
3461 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie,
3462 "Tx no desc");
3463 } else {
3464 if (mac_srs->srs_first != NULL)
3465 wakeup_worker = B_FALSE;
3466 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz);
3467 if (flag & MAC_TX_NO_ENQUEUE) {
3468 /*
3469 * If TX_QUEUED is not set, queue the
3470 * packet and let mac_tx_srs_drain()
3471 * set the TX_BLOCKED bit for the
3472 * reasons explained above. Otherwise,
3473 * return the mblks.
3474 */
3475 if (wakeup_worker) {
3476 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs,
3477 mp_chain, tail, cnt, sz);
3478 } else {
3479 MAC_TX_SET_NO_ENQUEUE(mac_srs,
3480 mp_chain, ret_mp, cookie);
3481 }
3482 } else {
3483 MAC_TX_SRS_TEST_HIWAT(mac_srs, mp_chain,
3484 tail, cnt, sz, cookie);
3485 }
3486 if (wakeup_worker)
3487 cv_signal(&mac_srs->srs_async);
3488 }
3489 return (cookie);
3490 }
3491
3492 /*
3493 * mac_tx_srs_enqueue
3494 *
3495 * This routine is called when Tx SRS is operating in either serializer
3496 * or bandwidth mode. In serializer mode, a packet will get enqueued
3497 * when a thread cannot enter SRS exclusively. In bandwidth mode,
3498 * packets gets queued if allowed byte-count limit for a tick is
3499 * exceeded. The action that gets taken when MAC_DROP_ON_NO_DESC and
3500 * MAC_TX_NO_ENQUEUE is set is different than when operaing in either
3501 * the default mode or fanout mode. Here packets get dropped or
3502 * returned back to the caller only after hi-watermark worth of data
3503 * is queued.
3504 */
3505 static mac_tx_cookie_t
mac_tx_srs_enqueue(mac_soft_ring_set_t * mac_srs,mblk_t * mp_chain,uint16_t flag,uintptr_t fanout_hint,mblk_t ** ret_mp)3506 mac_tx_srs_enqueue(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain,
3507 uint16_t flag, uintptr_t fanout_hint, mblk_t **ret_mp)
3508 {
3509 mac_tx_cookie_t cookie = 0;
3510 int cnt, sz;
3511 mblk_t *tail;
3512 boolean_t wakeup_worker = B_TRUE;
3513
3514 /*
3515 * Ignore fanout hint if we don't have multiple tx rings.
3516 */
3517 if (!MAC_TX_SOFT_RINGS(mac_srs))
3518 fanout_hint = 0;
3519
3520 if (mac_srs->srs_first != NULL)
3521 wakeup_worker = B_FALSE;
3522 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz);
3523 if (flag & MAC_DROP_ON_NO_DESC) {
3524 if (mac_srs->srs_count > mac_srs->srs_tx.st_hiwat) {
3525 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie,
3526 "Tx SRS hiwat");
3527 } else {
3528 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs,
3529 mp_chain, tail, cnt, sz);
3530 }
3531 } else if (flag & MAC_TX_NO_ENQUEUE) {
3532 if ((mac_srs->srs_count > mac_srs->srs_tx.st_hiwat) ||
3533 (mac_srs->srs_state & SRS_TX_WAKEUP_CLIENT)) {
3534 MAC_TX_SET_NO_ENQUEUE(mac_srs, mp_chain,
3535 ret_mp, cookie);
3536 } else {
3537 mp_chain->b_prev = (mblk_t *)fanout_hint;
3538 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs,
3539 mp_chain, tail, cnt, sz);
3540 }
3541 } else {
3542 /*
3543 * If you are BW_ENFORCED, just enqueue the
3544 * packet. srs_worker will drain it at the
3545 * prescribed rate. Before enqueueing, save
3546 * the fanout hint.
3547 */
3548 mp_chain->b_prev = (mblk_t *)fanout_hint;
3549 MAC_TX_SRS_TEST_HIWAT(mac_srs, mp_chain,
3550 tail, cnt, sz, cookie);
3551 }
3552 if (wakeup_worker)
3553 cv_signal(&mac_srs->srs_async);
3554 return (cookie);
3555 }
3556
3557 /*
3558 * There are seven tx modes:
3559 *
3560 * 1) Default mode (SRS_TX_DEFAULT)
3561 * 2) Serialization mode (SRS_TX_SERIALIZE)
3562 * 3) Fanout mode (SRS_TX_FANOUT)
3563 * 4) Bandwdith mode (SRS_TX_BW)
3564 * 5) Fanout and Bandwidth mode (SRS_TX_BW_FANOUT)
3565 * 6) aggr Tx mode (SRS_TX_AGGR)
3566 * 7) aggr Tx bw mode (SRS_TX_BW_AGGR)
3567 *
3568 * The tx mode in which an SRS operates is decided in mac_tx_srs_setup()
3569 * based on the number of Tx rings requested for an SRS and whether
3570 * bandwidth control is requested or not.
3571 *
3572 * The default mode (i.e., no fanout/no bandwidth) is used when the
3573 * underlying NIC does not have Tx rings or just one Tx ring. In this mode,
3574 * the SRS acts as a pass-thru. Packets will go directly to mac_tx_send().
3575 * When the underlying Tx ring runs out of Tx descs, it starts queueing up
3576 * packets in SRS. When flow-control is relieved, the srs_worker drains
3577 * the queued packets and informs blocked clients to restart sending
3578 * packets.
3579 *
3580 * In the SRS_TX_SERIALIZE mode, all calls to mac_tx() are serialized. This
3581 * mode is used when the link has no Tx rings or only one Tx ring.
3582 *
3583 * In the SRS_TX_FANOUT mode, packets will be fanned out to multiple
3584 * Tx rings. Each Tx ring will have a soft ring associated with it.
3585 * These soft rings will be hung off the Tx SRS. Queueing if it happens
3586 * due to lack of Tx desc will be in individual soft ring (and not srs)
3587 * associated with Tx ring.
3588 *
3589 * In the TX_BW mode, tx srs will allow packets to go down to Tx ring
3590 * only if bw is available. Otherwise the packets will be queued in
3591 * SRS. If fanout to multiple Tx rings is configured, the packets will
3592 * be fanned out among the soft rings associated with the Tx rings.
3593 *
3594 * In SRS_TX_AGGR mode, mac_tx_aggr_mode() routine is called. This routine
3595 * invokes an aggr function, aggr_find_tx_ring(), to find a pseudo Tx ring
3596 * belonging to a port on which the packet has to be sent. Aggr will
3597 * always have a pseudo Tx ring associated with it even when it is an
3598 * aggregation over a single NIC that has no Tx rings. Even in such a
3599 * case, the single pseudo Tx ring will have a soft ring associated with
3600 * it and the soft ring will hang off the SRS.
3601 *
3602 * If a bandwidth is specified for an aggr, SRS_TX_BW_AGGR mode is used.
3603 * In this mode, the bandwidth is first applied on the outgoing packets
3604 * and later mac_tx_addr_mode() function is called to send the packet out
3605 * of one of the pseudo Tx rings.
3606 *
3607 * Four flags are used in srs_state for indicating flow control
3608 * conditions : SRS_TX_BLOCKED, SRS_TX_HIWAT, SRS_TX_WAKEUP_CLIENT.
3609 * SRS_TX_BLOCKED indicates out of Tx descs. SRS expects a wakeup from the
3610 * driver below.
3611 * SRS_TX_HIWAT indicates packet count enqueued in Tx SRS exceeded Tx hiwat
3612 * and flow-control pressure is applied back to clients. The clients expect
3613 * wakeup when flow-control is relieved.
3614 * SRS_TX_WAKEUP_CLIENT get set when (flag == MAC_TX_NO_ENQUEUE) and mblk
3615 * got returned back to client either due to lack of Tx descs or due to bw
3616 * control reasons. The clients expect a wakeup when condition is relieved.
3617 *
3618 * The fourth argument to mac_tx() is the flag. Normally it will be 0 but
3619 * some clients set the following values too: MAC_DROP_ON_NO_DESC,
3620 * MAC_TX_NO_ENQUEUE
3621 * Mac clients that do not want packets to be enqueued in the mac layer set
3622 * MAC_DROP_ON_NO_DESC value. The packets won't be queued in the Tx SRS or
3623 * Tx soft rings but instead get dropped when the NIC runs out of desc. The
3624 * behaviour of this flag is different when the Tx is running in serializer
3625 * or bandwidth mode. Under these (Serializer, bandwidth) modes, the packet
3626 * get dropped when Tx high watermark is reached.
3627 * There are some mac clients like vsw, aggr that want the mblks to be
3628 * returned back to clients instead of being queued in Tx SRS (or Tx soft
3629 * rings) under flow-control (i.e., out of desc or exceeding bw limits)
3630 * conditions. These clients call mac_tx() with MAC_TX_NO_ENQUEUE flag set.
3631 * In the default and Tx fanout mode, the un-transmitted mblks will be
3632 * returned back to the clients when the driver runs out of Tx descs.
3633 * SRS_TX_WAKEUP_CLIENT (or S_RING_WAKEUP_CLIENT) will be set in SRS (or
3634 * soft ring) so that the clients can be woken up when Tx desc become
3635 * available. When running in serializer or bandwidth mode mode,
3636 * SRS_TX_WAKEUP_CLIENT will be set when tx hi-watermark is reached.
3637 */
3638
3639 mac_tx_func_t
mac_tx_get_func(uint32_t mode)3640 mac_tx_get_func(uint32_t mode)
3641 {
3642 return (mac_tx_mode_list[mode].mac_tx_func);
3643 }
3644
3645 /* ARGSUSED */
3646 static mac_tx_cookie_t
mac_tx_single_ring_mode(mac_soft_ring_set_t * mac_srs,mblk_t * mp_chain,uintptr_t fanout_hint,uint16_t flag,mblk_t ** ret_mp)3647 mac_tx_single_ring_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain,
3648 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp)
3649 {
3650 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx;
3651 mac_tx_stats_t stats;
3652 mac_tx_cookie_t cookie = 0;
3653
3654 ASSERT(srs_tx->st_mode == SRS_TX_DEFAULT);
3655
3656 /* Regular case with a single Tx ring */
3657 /*
3658 * SRS_TX_BLOCKED is set when underlying NIC runs
3659 * out of Tx descs and messages start getting
3660 * queued. It won't get reset until
3661 * tx_srs_drain() completely drains out the
3662 * messages.
3663 */
3664 if ((mac_srs->srs_state & SRS_ENQUEUED) != 0) {
3665 /* Tx descs/resources not available */
3666 mutex_enter(&mac_srs->srs_lock);
3667 if ((mac_srs->srs_state & SRS_ENQUEUED) != 0) {
3668 cookie = mac_tx_srs_no_desc(mac_srs, mp_chain,
3669 flag, ret_mp);
3670 mutex_exit(&mac_srs->srs_lock);
3671 return (cookie);
3672 }
3673 /*
3674 * While we were computing mblk count, the
3675 * flow control condition got relieved.
3676 * Continue with the transmission.
3677 */
3678 mutex_exit(&mac_srs->srs_lock);
3679 }
3680
3681 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2,
3682 mp_chain, &stats);
3683
3684 /*
3685 * Multiple threads could be here sending packets.
3686 * Under such conditions, it is not possible to
3687 * automically set SRS_TX_BLOCKED bit to indicate
3688 * out of tx desc condition. To atomically set
3689 * this, we queue the returned packet and do
3690 * the setting of SRS_TX_BLOCKED in
3691 * mac_tx_srs_drain().
3692 */
3693 if (mp_chain != NULL) {
3694 mutex_enter(&mac_srs->srs_lock);
3695 cookie = mac_tx_srs_no_desc(mac_srs, mp_chain, flag, ret_mp);
3696 mutex_exit(&mac_srs->srs_lock);
3697 return (cookie);
3698 }
3699 SRS_TX_STATS_UPDATE(mac_srs, &stats);
3700
3701 return (0);
3702 }
3703
3704 /*
3705 * mac_tx_serialize_mode
3706 *
3707 * This is an experimental mode implemented as per the request of PAE.
3708 * In this mode, all callers attempting to send a packet to the NIC
3709 * will get serialized. Only one thread at any time will access the
3710 * NIC to send the packet out.
3711 */
3712 /* ARGSUSED */
3713 static mac_tx_cookie_t
mac_tx_serializer_mode(mac_soft_ring_set_t * mac_srs,mblk_t * mp_chain,uintptr_t fanout_hint,uint16_t flag,mblk_t ** ret_mp)3714 mac_tx_serializer_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain,
3715 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp)
3716 {
3717 mac_tx_stats_t stats;
3718 mac_tx_cookie_t cookie = 0;
3719 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx;
3720
3721 /* Single ring, serialize below */
3722 ASSERT(srs_tx->st_mode == SRS_TX_SERIALIZE);
3723 mutex_enter(&mac_srs->srs_lock);
3724 if ((mac_srs->srs_first != NULL) ||
3725 (mac_srs->srs_state & SRS_PROC)) {
3726 /*
3727 * In serialization mode, queue all packets until
3728 * TX_HIWAT is set.
3729 * If drop bit is set, drop if TX_HIWAT is set.
3730 * If no_enqueue is set, still enqueue until hiwat
3731 * is set and return mblks after TX_HIWAT is set.
3732 */
3733 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain,
3734 flag, 0, ret_mp);
3735 mutex_exit(&mac_srs->srs_lock);
3736 return (cookie);
3737 }
3738 /*
3739 * No packets queued, nothing on proc and no flow
3740 * control condition. Fast-path, ok. Do inline
3741 * processing.
3742 */
3743 mac_srs->srs_state |= SRS_PROC;
3744 mutex_exit(&mac_srs->srs_lock);
3745
3746 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2,
3747 mp_chain, &stats);
3748
3749 mutex_enter(&mac_srs->srs_lock);
3750 mac_srs->srs_state &= ~SRS_PROC;
3751 if (mp_chain != NULL) {
3752 cookie = mac_tx_srs_enqueue(mac_srs,
3753 mp_chain, flag, 0, ret_mp);
3754 }
3755 if (mac_srs->srs_first != NULL) {
3756 /*
3757 * We processed inline our packet and a new
3758 * packet/s got queued while we were
3759 * processing. Wakeup srs worker
3760 */
3761 cv_signal(&mac_srs->srs_async);
3762 }
3763 mutex_exit(&mac_srs->srs_lock);
3764
3765 if (cookie == 0)
3766 SRS_TX_STATS_UPDATE(mac_srs, &stats);
3767
3768 return (cookie);
3769 }
3770
3771 /*
3772 * mac_tx_fanout_mode
3773 *
3774 * In this mode, the SRS will have access to multiple Tx rings to send
3775 * the packet out. The fanout hint that is passed as an argument is
3776 * used to find an appropriate ring to fanout the traffic. Each Tx
3777 * ring, in turn, will have a soft ring associated with it. If a Tx
3778 * ring runs out of Tx desc's the returned packet will be queued in
3779 * the soft ring associated with that Tx ring. The srs itself will not
3780 * queue any packets.
3781 */
3782
3783 #define MAC_TX_SOFT_RING_PROCESS(chain) { \
3784 index = COMPUTE_INDEX(hash, mac_srs->srs_tx_ring_count), \
3785 softring = mac_srs->srs_tx_soft_rings[index]; \
3786 cookie = mac_tx_soft_ring_process(softring, chain, flag, ret_mp); \
3787 DTRACE_PROBE2(tx__fanout, uint64_t, hash, uint_t, index); \
3788 }
3789
3790 static mac_tx_cookie_t
mac_tx_fanout_mode(mac_soft_ring_set_t * mac_srs,mblk_t * mp_chain,uintptr_t fanout_hint,uint16_t flag,mblk_t ** ret_mp)3791 mac_tx_fanout_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain,
3792 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp)
3793 {
3794 mac_soft_ring_t *softring;
3795 uint64_t hash;
3796 uint_t index;
3797 mac_tx_cookie_t cookie = 0;
3798
3799 ASSERT(mac_srs->srs_tx.st_mode == SRS_TX_FANOUT ||
3800 mac_srs->srs_tx.st_mode == SRS_TX_BW_FANOUT);
3801 if (fanout_hint != 0) {
3802 /*
3803 * The hint is specified by the caller, simply pass the
3804 * whole chain to the soft ring.
3805 */
3806 hash = HASH_HINT(fanout_hint);
3807 MAC_TX_SOFT_RING_PROCESS(mp_chain);
3808 } else {
3809 mblk_t *last_mp, *cur_mp, *sub_chain;
3810 uint64_t last_hash = 0;
3811 uint_t media = mac_srs->srs_mcip->mci_mip->mi_info.mi_media;
3812
3813 /*
3814 * Compute the hash from the contents (headers) of the
3815 * packets of the mblk chain. Split the chains into
3816 * subchains of the same conversation.
3817 *
3818 * Since there may be more than one ring used for
3819 * sub-chains of the same call, and since the caller
3820 * does not maintain per conversation state since it
3821 * passed a zero hint, unsent subchains will be
3822 * dropped.
3823 */
3824
3825 flag |= MAC_DROP_ON_NO_DESC;
3826 ret_mp = NULL;
3827
3828 ASSERT(ret_mp == NULL);
3829
3830 sub_chain = NULL;
3831 last_mp = NULL;
3832
3833 for (cur_mp = mp_chain; cur_mp != NULL;
3834 cur_mp = cur_mp->b_next) {
3835 hash = mac_pkt_hash(media, cur_mp, MAC_PKT_HASH_L4,
3836 B_TRUE);
3837 if (last_hash != 0 && hash != last_hash) {
3838 /*
3839 * Starting a different subchain, send current
3840 * chain out.
3841 */
3842 ASSERT(last_mp != NULL);
3843 last_mp->b_next = NULL;
3844 MAC_TX_SOFT_RING_PROCESS(sub_chain);
3845 sub_chain = NULL;
3846 }
3847
3848 /* add packet to subchain */
3849 if (sub_chain == NULL)
3850 sub_chain = cur_mp;
3851 last_mp = cur_mp;
3852 last_hash = hash;
3853 }
3854
3855 if (sub_chain != NULL) {
3856 /* send last subchain */
3857 ASSERT(last_mp != NULL);
3858 last_mp->b_next = NULL;
3859 MAC_TX_SOFT_RING_PROCESS(sub_chain);
3860 }
3861
3862 cookie = 0;
3863 }
3864
3865 return (cookie);
3866 }
3867
3868 /*
3869 * mac_tx_bw_mode
3870 *
3871 * In the bandwidth mode, Tx srs will allow packets to go down to Tx ring
3872 * only if bw is available. Otherwise the packets will be queued in
3873 * SRS. If the SRS has multiple Tx rings, then packets will get fanned
3874 * out to a Tx rings.
3875 */
3876 static mac_tx_cookie_t
mac_tx_bw_mode(mac_soft_ring_set_t * mac_srs,mblk_t * mp_chain,uintptr_t fanout_hint,uint16_t flag,mblk_t ** ret_mp)3877 mac_tx_bw_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain,
3878 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp)
3879 {
3880 int cnt, sz;
3881 mblk_t *tail;
3882 mac_tx_cookie_t cookie = 0;
3883 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx;
3884 clock_t now;
3885
3886 ASSERT(TX_BANDWIDTH_MODE(mac_srs));
3887 ASSERT(mac_srs->srs_type & SRST_BW_CONTROL);
3888 mutex_enter(&mac_srs->srs_lock);
3889 if (mac_srs->srs_bw->mac_bw_limit == 0) {
3890 /*
3891 * zero bandwidth, no traffic is sent: drop the packets,
3892 * or return the whole chain if the caller requests all
3893 * unsent packets back.
3894 */
3895 if (flag & MAC_TX_NO_ENQUEUE) {
3896 cookie = (mac_tx_cookie_t)mac_srs;
3897 *ret_mp = mp_chain;
3898 } else {
3899 MAC_TX_SRS_DROP_MESSAGE(mac_srs, mp_chain, cookie,
3900 "Tx no bandwidth");
3901 }
3902 mutex_exit(&mac_srs->srs_lock);
3903 return (cookie);
3904 } else if ((mac_srs->srs_first != NULL) ||
3905 (mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED)) {
3906 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, flag,
3907 fanout_hint, ret_mp);
3908 mutex_exit(&mac_srs->srs_lock);
3909 return (cookie);
3910 }
3911 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz);
3912 now = ddi_get_lbolt();
3913 if (mac_srs->srs_bw->mac_bw_curr_time != now) {
3914 mac_srs->srs_bw->mac_bw_curr_time = now;
3915 mac_srs->srs_bw->mac_bw_used = 0;
3916 } else if (mac_srs->srs_bw->mac_bw_used >
3917 mac_srs->srs_bw->mac_bw_limit) {
3918 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED;
3919 MAC_TX_SRS_ENQUEUE_CHAIN(mac_srs,
3920 mp_chain, tail, cnt, sz);
3921 /*
3922 * Wakeup worker thread. Note that worker
3923 * thread has to be woken up so that it
3924 * can fire up the timer to be woken up
3925 * on the next tick. Also once
3926 * BW_ENFORCED is set, it can only be
3927 * reset by srs_worker thread. Until then
3928 * all packets will get queued up in SRS
3929 * and hence this this code path won't be
3930 * entered until BW_ENFORCED is reset.
3931 */
3932 cv_signal(&mac_srs->srs_async);
3933 mutex_exit(&mac_srs->srs_lock);
3934 return (cookie);
3935 }
3936
3937 mac_srs->srs_bw->mac_bw_used += sz;
3938 mutex_exit(&mac_srs->srs_lock);
3939
3940 if (srs_tx->st_mode == SRS_TX_BW_FANOUT) {
3941 mac_soft_ring_t *softring;
3942 uint_t indx, hash;
3943
3944 hash = HASH_HINT(fanout_hint);
3945 indx = COMPUTE_INDEX(hash,
3946 mac_srs->srs_tx_ring_count);
3947 softring = mac_srs->srs_tx_soft_rings[indx];
3948 return (mac_tx_soft_ring_process(softring, mp_chain, flag,
3949 ret_mp));
3950 } else if (srs_tx->st_mode == SRS_TX_BW_AGGR) {
3951 return (mac_tx_aggr_mode(mac_srs, mp_chain,
3952 fanout_hint, flag, ret_mp));
3953 } else {
3954 mac_tx_stats_t stats;
3955
3956 mp_chain = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2,
3957 mp_chain, &stats);
3958
3959 if (mp_chain != NULL) {
3960 mutex_enter(&mac_srs->srs_lock);
3961 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz);
3962 if (mac_srs->srs_bw->mac_bw_used > sz)
3963 mac_srs->srs_bw->mac_bw_used -= sz;
3964 else
3965 mac_srs->srs_bw->mac_bw_used = 0;
3966 cookie = mac_tx_srs_enqueue(mac_srs, mp_chain, flag,
3967 fanout_hint, ret_mp);
3968 mutex_exit(&mac_srs->srs_lock);
3969 return (cookie);
3970 }
3971 SRS_TX_STATS_UPDATE(mac_srs, &stats);
3972
3973 return (0);
3974 }
3975 }
3976
3977 /*
3978 * mac_tx_aggr_mode
3979 *
3980 * This routine invokes an aggr function, aggr_find_tx_ring(), to find
3981 * a (pseudo) Tx ring belonging to a port on which the packet has to
3982 * be sent. aggr_find_tx_ring() first finds the outgoing port based on
3983 * L2/L3/L4 policy and then uses the fanout_hint passed to it to pick
3984 * a Tx ring from the selected port.
3985 *
3986 * Note that a port can be deleted from the aggregation. In such a case,
3987 * the aggregation layer first separates the port from the rest of the
3988 * ports making sure that port (and thus any Tx rings associated with
3989 * it) won't get selected in the call to aggr_find_tx_ring() function.
3990 * Later calls are made to mac_group_rem_ring() passing pseudo Tx ring
3991 * handles one by one which in turn will quiesce the Tx SRS and remove
3992 * the soft ring associated with the pseudo Tx ring. Unlike Rx side
3993 * where a cookie is used to protect against mac_rx_ring() calls on
3994 * rings that have been removed, no such cookie is needed on the Tx
3995 * side as the pseudo Tx ring won't be available anymore to
3996 * aggr_find_tx_ring() once the port has been removed.
3997 */
3998 static mac_tx_cookie_t
mac_tx_aggr_mode(mac_soft_ring_set_t * mac_srs,mblk_t * mp_chain,uintptr_t fanout_hint,uint16_t flag,mblk_t ** ret_mp)3999 mac_tx_aggr_mode(mac_soft_ring_set_t *mac_srs, mblk_t *mp_chain,
4000 uintptr_t fanout_hint, uint16_t flag, mblk_t **ret_mp)
4001 {
4002 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx;
4003 mac_tx_ring_fn_t find_tx_ring_fn;
4004 mac_ring_handle_t ring = NULL;
4005 void *arg;
4006 mac_soft_ring_t *sringp;
4007
4008 find_tx_ring_fn = srs_tx->st_capab_aggr.mca_find_tx_ring_fn;
4009 arg = srs_tx->st_capab_aggr.mca_arg;
4010 if (find_tx_ring_fn(arg, mp_chain, fanout_hint, &ring) == NULL)
4011 return (0);
4012 sringp = srs_tx->st_soft_rings[((mac_ring_t *)ring)->mr_index];
4013 return (mac_tx_soft_ring_process(sringp, mp_chain, flag, ret_mp));
4014 }
4015
4016 void
mac_tx_invoke_callbacks(mac_client_impl_t * mcip,mac_tx_cookie_t cookie)4017 mac_tx_invoke_callbacks(mac_client_impl_t *mcip, mac_tx_cookie_t cookie)
4018 {
4019 mac_cb_t *mcb;
4020 mac_tx_notify_cb_t *mtnfp;
4021
4022 /* Wakeup callback registered clients */
4023 MAC_CALLBACK_WALKER_INC(&mcip->mci_tx_notify_cb_info);
4024 for (mcb = mcip->mci_tx_notify_cb_list; mcb != NULL;
4025 mcb = mcb->mcb_nextp) {
4026 mtnfp = (mac_tx_notify_cb_t *)mcb->mcb_objp;
4027 mtnfp->mtnf_fn(mtnfp->mtnf_arg, cookie);
4028 }
4029 MAC_CALLBACK_WALKER_DCR(&mcip->mci_tx_notify_cb_info,
4030 &mcip->mci_tx_notify_cb_list);
4031 }
4032
4033 /* ARGSUSED */
4034 void
mac_tx_srs_drain(mac_soft_ring_set_t * mac_srs,uint_t proc_type)4035 mac_tx_srs_drain(mac_soft_ring_set_t *mac_srs, uint_t proc_type)
4036 {
4037 mblk_t *head, *tail;
4038 size_t sz;
4039 uint32_t tx_mode;
4040 uint_t saved_pkt_count;
4041 mac_tx_stats_t stats;
4042 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx;
4043 clock_t now;
4044
4045 saved_pkt_count = 0;
4046 ASSERT(mutex_owned(&mac_srs->srs_lock));
4047 ASSERT(!(mac_srs->srs_state & SRS_PROC));
4048
4049 mac_srs->srs_state |= SRS_PROC;
4050
4051 tx_mode = srs_tx->st_mode;
4052 if (tx_mode == SRS_TX_DEFAULT || tx_mode == SRS_TX_SERIALIZE) {
4053 if (mac_srs->srs_first != NULL) {
4054 head = mac_srs->srs_first;
4055 tail = mac_srs->srs_last;
4056 saved_pkt_count = mac_srs->srs_count;
4057 mac_srs->srs_first = NULL;
4058 mac_srs->srs_last = NULL;
4059 mac_srs->srs_count = 0;
4060 mutex_exit(&mac_srs->srs_lock);
4061
4062 head = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2,
4063 head, &stats);
4064
4065 mutex_enter(&mac_srs->srs_lock);
4066 if (head != NULL) {
4067 /* Device out of tx desc, set block */
4068 if (head->b_next == NULL)
4069 VERIFY(head == tail);
4070 tail->b_next = mac_srs->srs_first;
4071 mac_srs->srs_first = head;
4072 mac_srs->srs_count +=
4073 (saved_pkt_count - stats.mts_opackets);
4074 if (mac_srs->srs_last == NULL)
4075 mac_srs->srs_last = tail;
4076 MAC_TX_SRS_BLOCK(mac_srs, head);
4077 } else {
4078 srs_tx->st_woken_up = B_FALSE;
4079 SRS_TX_STATS_UPDATE(mac_srs, &stats);
4080 }
4081 }
4082 } else if (tx_mode == SRS_TX_BW) {
4083 /*
4084 * We are here because the timer fired and we have some data
4085 * to tranmit. Also mac_tx_srs_worker should have reset
4086 * SRS_BW_ENFORCED flag
4087 */
4088 ASSERT(!(mac_srs->srs_bw->mac_bw_state & SRS_BW_ENFORCED));
4089 head = tail = mac_srs->srs_first;
4090 while (mac_srs->srs_first != NULL) {
4091 tail = mac_srs->srs_first;
4092 tail->b_prev = NULL;
4093 mac_srs->srs_first = tail->b_next;
4094 if (mac_srs->srs_first == NULL)
4095 mac_srs->srs_last = NULL;
4096 mac_srs->srs_count--;
4097 sz = msgdsize(tail);
4098 mac_srs->srs_size -= sz;
4099 saved_pkt_count++;
4100 MAC_TX_UPDATE_BW_INFO(mac_srs, sz);
4101
4102 if (mac_srs->srs_bw->mac_bw_used <
4103 mac_srs->srs_bw->mac_bw_limit)
4104 continue;
4105
4106 now = ddi_get_lbolt();
4107 if (mac_srs->srs_bw->mac_bw_curr_time != now) {
4108 mac_srs->srs_bw->mac_bw_curr_time = now;
4109 mac_srs->srs_bw->mac_bw_used = sz;
4110 continue;
4111 }
4112 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED;
4113 break;
4114 }
4115
4116 ASSERT((head == NULL && tail == NULL) ||
4117 (head != NULL && tail != NULL));
4118 if (tail != NULL) {
4119 tail->b_next = NULL;
4120 mutex_exit(&mac_srs->srs_lock);
4121
4122 head = mac_tx_send(srs_tx->st_arg1, srs_tx->st_arg2,
4123 head, &stats);
4124
4125 mutex_enter(&mac_srs->srs_lock);
4126 if (head != NULL) {
4127 uint_t size_sent;
4128
4129 /* Device out of tx desc, set block */
4130 if (head->b_next == NULL)
4131 VERIFY(head == tail);
4132 tail->b_next = mac_srs->srs_first;
4133 mac_srs->srs_first = head;
4134 mac_srs->srs_count +=
4135 (saved_pkt_count - stats.mts_opackets);
4136 if (mac_srs->srs_last == NULL)
4137 mac_srs->srs_last = tail;
4138 size_sent = sz - stats.mts_obytes;
4139 mac_srs->srs_size += size_sent;
4140 mac_srs->srs_bw->mac_bw_sz += size_sent;
4141 if (mac_srs->srs_bw->mac_bw_used > size_sent) {
4142 mac_srs->srs_bw->mac_bw_used -=
4143 size_sent;
4144 } else {
4145 mac_srs->srs_bw->mac_bw_used = 0;
4146 }
4147 MAC_TX_SRS_BLOCK(mac_srs, head);
4148 } else {
4149 srs_tx->st_woken_up = B_FALSE;
4150 SRS_TX_STATS_UPDATE(mac_srs, &stats);
4151 }
4152 }
4153 } else if (tx_mode == SRS_TX_BW_FANOUT || tx_mode == SRS_TX_BW_AGGR) {
4154 mblk_t *prev;
4155 uint64_t hint;
4156
4157 /*
4158 * We are here because the timer fired and we
4159 * have some quota to tranmit.
4160 */
4161 prev = NULL;
4162 head = tail = mac_srs->srs_first;
4163 while (mac_srs->srs_first != NULL) {
4164 tail = mac_srs->srs_first;
4165 mac_srs->srs_first = tail->b_next;
4166 if (mac_srs->srs_first == NULL)
4167 mac_srs->srs_last = NULL;
4168 mac_srs->srs_count--;
4169 sz = msgdsize(tail);
4170 mac_srs->srs_size -= sz;
4171 mac_srs->srs_bw->mac_bw_used += sz;
4172 if (prev == NULL)
4173 hint = (ulong_t)tail->b_prev;
4174 if (hint != (ulong_t)tail->b_prev) {
4175 prev->b_next = NULL;
4176 mutex_exit(&mac_srs->srs_lock);
4177 TX_SRS_TO_SOFT_RING(mac_srs, head, hint);
4178 head = tail;
4179 hint = (ulong_t)tail->b_prev;
4180 mutex_enter(&mac_srs->srs_lock);
4181 }
4182
4183 prev = tail;
4184 tail->b_prev = NULL;
4185 if (mac_srs->srs_bw->mac_bw_used <
4186 mac_srs->srs_bw->mac_bw_limit)
4187 continue;
4188
4189 now = ddi_get_lbolt();
4190 if (mac_srs->srs_bw->mac_bw_curr_time != now) {
4191 mac_srs->srs_bw->mac_bw_curr_time = now;
4192 mac_srs->srs_bw->mac_bw_used = 0;
4193 continue;
4194 }
4195 mac_srs->srs_bw->mac_bw_state |= SRS_BW_ENFORCED;
4196 break;
4197 }
4198 ASSERT((head == NULL && tail == NULL) ||
4199 (head != NULL && tail != NULL));
4200 if (tail != NULL) {
4201 tail->b_next = NULL;
4202 mutex_exit(&mac_srs->srs_lock);
4203 TX_SRS_TO_SOFT_RING(mac_srs, head, hint);
4204 mutex_enter(&mac_srs->srs_lock);
4205 }
4206 }
4207 /*
4208 * SRS_TX_FANOUT case not considered here because packets
4209 * won't be queued in the SRS for this case. Packets will
4210 * be sent directly to soft rings underneath and if there
4211 * is any queueing at all, it would be in Tx side soft
4212 * rings.
4213 */
4214
4215 /*
4216 * When srs_count becomes 0, reset SRS_TX_HIWAT and
4217 * SRS_TX_WAKEUP_CLIENT and wakeup registered clients.
4218 */
4219 if (mac_srs->srs_count == 0 && (mac_srs->srs_state &
4220 (SRS_TX_HIWAT | SRS_TX_WAKEUP_CLIENT | SRS_ENQUEUED))) {
4221 mac_client_impl_t *mcip = mac_srs->srs_mcip;
4222 boolean_t wakeup_required = B_FALSE;
4223
4224 if (mac_srs->srs_state &
4225 (SRS_TX_HIWAT|SRS_TX_WAKEUP_CLIENT)) {
4226 wakeup_required = B_TRUE;
4227 }
4228 mac_srs->srs_state &= ~(SRS_TX_HIWAT |
4229 SRS_TX_WAKEUP_CLIENT | SRS_ENQUEUED);
4230 mutex_exit(&mac_srs->srs_lock);
4231 if (wakeup_required) {
4232 mac_tx_invoke_callbacks(mcip, (mac_tx_cookie_t)mac_srs);
4233 /*
4234 * If the client is not the primary MAC client, then we
4235 * need to send the notification to the clients upper
4236 * MAC, i.e. mci_upper_mip.
4237 */
4238 mac_tx_notify(mcip->mci_upper_mip != NULL ?
4239 mcip->mci_upper_mip : mcip->mci_mip);
4240 }
4241 mutex_enter(&mac_srs->srs_lock);
4242 }
4243 mac_srs->srs_state &= ~SRS_PROC;
4244 }
4245
4246 /*
4247 * Given a packet, get the flow_entry that identifies the flow
4248 * to which that packet belongs. The flow_entry will contain
4249 * the transmit function to be used to send the packet. If the
4250 * function returns NULL, the packet should be sent using the
4251 * underlying NIC.
4252 */
4253 static flow_entry_t *
mac_tx_classify(mac_impl_t * mip,mblk_t * mp)4254 mac_tx_classify(mac_impl_t *mip, mblk_t *mp)
4255 {
4256 flow_entry_t *flent = NULL;
4257 mac_client_impl_t *mcip;
4258 int err;
4259
4260 /*
4261 * Do classification on the packet.
4262 */
4263 err = mac_flow_lookup(mip->mi_flow_tab, mp, FLOW_OUTBOUND, &flent);
4264 if (err != 0)
4265 return (NULL);
4266
4267 /*
4268 * This flent might just be an additional one on the MAC client,
4269 * i.e. for classification purposes (different fdesc), however
4270 * the resources, SRS et. al., are in the mci_flent, so if
4271 * this isn't the mci_flent, we need to get it.
4272 */
4273 if ((mcip = flent->fe_mcip) != NULL && mcip->mci_flent != flent) {
4274 FLOW_REFRELE(flent);
4275 flent = mcip->mci_flent;
4276 FLOW_TRY_REFHOLD(flent, err);
4277 if (err != 0)
4278 return (NULL);
4279 }
4280
4281 return (flent);
4282 }
4283
4284 /*
4285 * This macro is only meant to be used by mac_tx_send().
4286 */
4287 #define CHECK_VID_AND_ADD_TAG(mp) { \
4288 if (vid_check) { \
4289 int err = 0; \
4290 \
4291 MAC_VID_CHECK(src_mcip, (mp), err); \
4292 if (err != 0) { \
4293 freemsg((mp)); \
4294 (mp) = next; \
4295 oerrors++; \
4296 continue; \
4297 } \
4298 } \
4299 if (add_tag) { \
4300 (mp) = mac_add_vlan_tag((mp), 0, vid); \
4301 if ((mp) == NULL) { \
4302 (mp) = next; \
4303 oerrors++; \
4304 continue; \
4305 } \
4306 } \
4307 }
4308
4309 mblk_t *
mac_tx_send(mac_client_handle_t mch,mac_ring_handle_t ring,mblk_t * mp_chain,mac_tx_stats_t * stats)4310 mac_tx_send(mac_client_handle_t mch, mac_ring_handle_t ring, mblk_t *mp_chain,
4311 mac_tx_stats_t *stats)
4312 {
4313 mac_client_impl_t *src_mcip = (mac_client_impl_t *)mch;
4314 mac_impl_t *mip = src_mcip->mci_mip;
4315 uint_t obytes = 0, opackets = 0, oerrors = 0;
4316 mblk_t *mp = NULL, *next;
4317 boolean_t vid_check, add_tag;
4318 uint16_t vid = 0;
4319
4320 if (mip->mi_nclients > 1) {
4321 vid_check = MAC_VID_CHECK_NEEDED(src_mcip);
4322 add_tag = MAC_TAG_NEEDED(src_mcip);
4323 if (add_tag)
4324 vid = mac_client_vid(mch);
4325 } else {
4326 ASSERT(mip->mi_nclients == 1);
4327 vid_check = add_tag = B_FALSE;
4328 }
4329
4330 /*
4331 * Fastpath: if there's only one client, we simply send
4332 * the packet down to the underlying NIC.
4333 */
4334 if (mip->mi_nactiveclients == 1) {
4335 DTRACE_PROBE2(fastpath,
4336 mac_client_impl_t *, src_mcip, mblk_t *, mp_chain);
4337
4338 mp = mp_chain;
4339 while (mp != NULL) {
4340 next = mp->b_next;
4341 mp->b_next = NULL;
4342 opackets++;
4343 obytes += (mp->b_cont == NULL ? MBLKL(mp) :
4344 msgdsize(mp));
4345
4346 CHECK_VID_AND_ADD_TAG(mp);
4347 mp = mac_provider_tx(mip, ring, mp, src_mcip);
4348
4349 /*
4350 * If the driver is out of descriptors and does a
4351 * partial send it will return a chain of unsent
4352 * mblks. Adjust the accounting stats.
4353 */
4354 if (mp != NULL) {
4355 opackets--;
4356 obytes -= msgdsize(mp);
4357 mp->b_next = next;
4358 break;
4359 }
4360 mp = next;
4361 }
4362 goto done;
4363 }
4364
4365 /*
4366 * No fastpath, we either have more than one MAC client
4367 * defined on top of the same MAC, or one or more MAC
4368 * client promiscuous callbacks.
4369 */
4370 DTRACE_PROBE3(slowpath, mac_client_impl_t *,
4371 src_mcip, int, mip->mi_nclients, mblk_t *, mp_chain);
4372
4373 mp = mp_chain;
4374 while (mp != NULL) {
4375 flow_entry_t *dst_flow_ent;
4376 void *flow_cookie;
4377 size_t pkt_size;
4378
4379 next = mp->b_next;
4380 mp->b_next = NULL;
4381 opackets++;
4382 pkt_size = (mp->b_cont == NULL ? MBLKL(mp) : msgdsize(mp));
4383 obytes += pkt_size;
4384 CHECK_VID_AND_ADD_TAG(mp);
4385
4386 /*
4387 * Find the destination.
4388 */
4389 dst_flow_ent = mac_tx_classify(mip, mp);
4390
4391 if (dst_flow_ent != NULL) {
4392 /*
4393 * Got a matching flow. It's either another
4394 * MAC client, or a broadcast/multicast flow.
4395 */
4396 flow_cookie = mac_flow_get_client_cookie(dst_flow_ent);
4397
4398 if (flow_cookie != NULL) {
4399 /*
4400 * The vnic_bcast_send function expects
4401 * to receive the sender MAC client
4402 * as value for arg2.
4403 */
4404 mac_bcast_send(flow_cookie, src_mcip, mp,
4405 B_TRUE);
4406 } else {
4407 /*
4408 * loopback the packet to a local MAC
4409 * client. We force a context switch
4410 * if both source and destination MAC
4411 * clients are used by IP, i.e.
4412 * bypass is set.
4413 */
4414 boolean_t do_switch;
4415
4416 mac_client_impl_t *dst_mcip =
4417 dst_flow_ent->fe_mcip;
4418
4419 /*
4420 * Check if there are promiscuous mode
4421 * callbacks defined. This check is
4422 * done here in the 'else' case and
4423 * not in other cases because this
4424 * path is for local loopback
4425 * communication which does not go
4426 * through MAC_TX(). For paths that go
4427 * through MAC_TX(), the promisc_list
4428 * check is done inside the MAC_TX()
4429 * macro.
4430 */
4431 if (mip->mi_promisc_list != NULL) {
4432 mac_promisc_dispatch(mip, mp, src_mcip,
4433 B_TRUE);
4434 }
4435
4436 do_switch = ((src_mcip->mci_state_flags &
4437 dst_mcip->mci_state_flags &
4438 MCIS_CLIENT_POLL_CAPABLE) != 0);
4439
4440 mac_hw_emul(&mp, NULL, NULL, MAC_ALL_EMULS);
4441 if (mp != NULL) {
4442 (dst_flow_ent->fe_cb_fn)(
4443 dst_flow_ent->fe_cb_arg1,
4444 dst_flow_ent->fe_cb_arg2,
4445 mp, do_switch);
4446 }
4447
4448 }
4449 FLOW_REFRELE(dst_flow_ent);
4450 } else {
4451 /*
4452 * Unknown destination, send via the underlying
4453 * NIC.
4454 */
4455 mp = mac_provider_tx(mip, ring, mp, src_mcip);
4456 if (mp != NULL) {
4457 /*
4458 * Adjust for the last packet that
4459 * could not be transmitted
4460 */
4461 opackets--;
4462 obytes -= pkt_size;
4463 mp->b_next = next;
4464 break;
4465 }
4466 }
4467 mp = next;
4468 }
4469
4470 done:
4471 stats->mts_obytes = obytes;
4472 stats->mts_opackets = opackets;
4473 stats->mts_oerrors = oerrors;
4474 return (mp);
4475 }
4476
4477 /*
4478 * mac_tx_srs_ring_present
4479 *
4480 * Returns whether the specified ring is part of the specified SRS.
4481 */
4482 boolean_t
mac_tx_srs_ring_present(mac_soft_ring_set_t * srs,mac_ring_t * tx_ring)4483 mac_tx_srs_ring_present(mac_soft_ring_set_t *srs, mac_ring_t *tx_ring)
4484 {
4485 int i;
4486 mac_soft_ring_t *soft_ring;
4487
4488 if (srs->srs_tx.st_arg2 == tx_ring)
4489 return (B_TRUE);
4490
4491 for (i = 0; i < srs->srs_tx_ring_count; i++) {
4492 soft_ring = srs->srs_tx_soft_rings[i];
4493 if (soft_ring->s_ring_tx_arg2 == tx_ring)
4494 return (B_TRUE);
4495 }
4496
4497 return (B_FALSE);
4498 }
4499
4500 /*
4501 * mac_tx_srs_get_soft_ring
4502 *
4503 * Returns the TX soft ring associated with the given ring, if present.
4504 */
4505 mac_soft_ring_t *
mac_tx_srs_get_soft_ring(mac_soft_ring_set_t * srs,mac_ring_t * tx_ring)4506 mac_tx_srs_get_soft_ring(mac_soft_ring_set_t *srs, mac_ring_t *tx_ring)
4507 {
4508 int i;
4509 mac_soft_ring_t *soft_ring;
4510
4511 if (srs->srs_tx.st_arg2 == tx_ring)
4512 return (NULL);
4513
4514 for (i = 0; i < srs->srs_tx_ring_count; i++) {
4515 soft_ring = srs->srs_tx_soft_rings[i];
4516 if (soft_ring->s_ring_tx_arg2 == tx_ring)
4517 return (soft_ring);
4518 }
4519
4520 return (NULL);
4521 }
4522
4523 /*
4524 * mac_tx_srs_wakeup
4525 *
4526 * Called when Tx desc become available. Wakeup the appropriate worker
4527 * thread after resetting the SRS_TX_BLOCKED/S_RING_BLOCK bit in the
4528 * state field.
4529 */
4530 void
mac_tx_srs_wakeup(mac_soft_ring_set_t * mac_srs,mac_ring_handle_t ring)4531 mac_tx_srs_wakeup(mac_soft_ring_set_t *mac_srs, mac_ring_handle_t ring)
4532 {
4533 int i;
4534 mac_soft_ring_t *sringp;
4535 mac_srs_tx_t *srs_tx = &mac_srs->srs_tx;
4536
4537 mutex_enter(&mac_srs->srs_lock);
4538 /*
4539 * srs_tx_ring_count == 0 is the single ring mode case. In
4540 * this mode, there will not be Tx soft rings associated
4541 * with the SRS.
4542 */
4543 if (!MAC_TX_SOFT_RINGS(mac_srs)) {
4544 if (srs_tx->st_arg2 == ring &&
4545 mac_srs->srs_state & SRS_TX_BLOCKED) {
4546 mac_srs->srs_state &= ~SRS_TX_BLOCKED;
4547 srs_tx->st_stat.mts_unblockcnt++;
4548 cv_signal(&mac_srs->srs_async);
4549 }
4550 /*
4551 * A wakeup can come before tx_srs_drain() could
4552 * grab srs lock and set SRS_TX_BLOCKED. So
4553 * always set woken_up flag when we come here.
4554 */
4555 srs_tx->st_woken_up = B_TRUE;
4556 mutex_exit(&mac_srs->srs_lock);
4557 return;
4558 }
4559
4560 /*
4561 * If you are here, it is for FANOUT, BW_FANOUT,
4562 * AGGR_MODE or AGGR_BW_MODE case
4563 */
4564 for (i = 0; i < mac_srs->srs_tx_ring_count; i++) {
4565 sringp = mac_srs->srs_tx_soft_rings[i];
4566 mutex_enter(&sringp->s_ring_lock);
4567 if (sringp->s_ring_tx_arg2 == ring) {
4568 if (sringp->s_ring_state & S_RING_BLOCK) {
4569 sringp->s_ring_state &= ~S_RING_BLOCK;
4570 sringp->s_st_stat.mts_unblockcnt++;
4571 cv_signal(&sringp->s_ring_async);
4572 }
4573 sringp->s_ring_tx_woken_up = B_TRUE;
4574 }
4575 mutex_exit(&sringp->s_ring_lock);
4576 }
4577 mutex_exit(&mac_srs->srs_lock);
4578 }
4579
4580 /*
4581 * Once the driver is done draining, send a MAC_NOTE_TX notification to unleash
4582 * the blocked clients again.
4583 */
4584 void
mac_tx_notify(mac_impl_t * mip)4585 mac_tx_notify(mac_impl_t *mip)
4586 {
4587 i_mac_notify(mip, MAC_NOTE_TX);
4588 }
4589
4590 /*
4591 * RX SOFTRING RELATED FUNCTIONS
4592 *
4593 * These functions really belong in mac_soft_ring.c and here for
4594 * a short period.
4595 */
4596
4597 #define SOFT_RING_ENQUEUE_CHAIN(ringp, mp, tail, cnt, sz) { \
4598 /* \
4599 * Enqueue our mblk chain. \
4600 */ \
4601 ASSERT(MUTEX_HELD(&(ringp)->s_ring_lock)); \
4602 \
4603 if ((ringp)->s_ring_last != NULL) \
4604 (ringp)->s_ring_last->b_next = (mp); \
4605 else \
4606 (ringp)->s_ring_first = (mp); \
4607 (ringp)->s_ring_last = (tail); \
4608 (ringp)->s_ring_count += (cnt); \
4609 ASSERT((ringp)->s_ring_count > 0); \
4610 if ((ringp)->s_ring_type & ST_RING_BW_CTL) { \
4611 (ringp)->s_ring_size += sz; \
4612 } \
4613 }
4614
4615 /*
4616 * Default entry point to deliver a packet chain to a MAC client.
4617 * If the MAC client has flows, do the classification with these
4618 * flows as well.
4619 */
4620 /* ARGSUSED */
4621 void
mac_rx_deliver(void * arg1,mac_resource_handle_t mrh,mblk_t * mp_chain,mac_header_info_t * arg3)4622 mac_rx_deliver(void *arg1, mac_resource_handle_t mrh, mblk_t *mp_chain,
4623 mac_header_info_t *arg3)
4624 {
4625 mac_client_impl_t *mcip = arg1;
4626
4627 if (mcip->mci_nvids == 1 &&
4628 !(mcip->mci_state_flags & MCIS_STRIP_DISABLE)) {
4629 /*
4630 * If the client has exactly one VID associated with it
4631 * and striping of VLAN header is not disabled,
4632 * remove the VLAN tag from the packet before
4633 * passing it on to the client's receive callback.
4634 * Note that this needs to be done after we dispatch
4635 * the packet to the promiscuous listeners of the
4636 * client, since they expect to see the whole
4637 * frame including the VLAN headers.
4638 *
4639 * The MCIS_STRIP_DISABLE is only issued when sun4v
4640 * vsw is in play.
4641 */
4642 mp_chain = mac_strip_vlan_tag_chain(mp_chain);
4643 }
4644
4645 mcip->mci_rx_fn(mcip->mci_rx_arg, mrh, mp_chain, B_FALSE);
4646 }
4647
4648 /*
4649 * Process a chain for a given soft ring. If the number of packets
4650 * queued in the SRS and its associated soft rings (including this
4651 * one) is very small (tracked by srs_poll_pkt_cnt) then allow the
4652 * entering thread (interrupt or poll thread) to process the chain
4653 * inline. This is meant to reduce latency under low load.
4654 *
4655 * The proc and arg for each mblk is already stored in the mblk in
4656 * appropriate places.
4657 */
4658 /* ARGSUSED */
4659 void
mac_rx_soft_ring_process(mac_client_impl_t * mcip,mac_soft_ring_t * ringp,mblk_t * mp_chain,mblk_t * tail,int cnt,size_t sz)4660 mac_rx_soft_ring_process(mac_client_impl_t *mcip, mac_soft_ring_t *ringp,
4661 mblk_t *mp_chain, mblk_t *tail, int cnt, size_t sz)
4662 {
4663 mac_direct_rx_t proc;
4664 void *arg1;
4665 mac_resource_handle_t arg2;
4666 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set;
4667
4668 ASSERT(ringp != NULL);
4669 ASSERT(mp_chain != NULL);
4670 ASSERT(tail != NULL);
4671 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock));
4672
4673 mutex_enter(&ringp->s_ring_lock);
4674 ringp->s_ring_total_inpkt += cnt;
4675 ringp->s_ring_total_rbytes += sz;
4676 if ((mac_srs->srs_rx.sr_poll_pkt_cnt <= 1) &&
4677 !(ringp->s_ring_type & ST_RING_WORKER_ONLY)) {
4678 /* If on processor or blanking on, then enqueue and return */
4679 if (ringp->s_ring_state & S_RING_BLANK ||
4680 ringp->s_ring_state & S_RING_PROC) {
4681 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz);
4682 mutex_exit(&ringp->s_ring_lock);
4683 return;
4684 }
4685 proc = ringp->s_ring_rx_func;
4686 arg1 = ringp->s_ring_rx_arg1;
4687 arg2 = ringp->s_ring_rx_arg2;
4688 /*
4689 * See if anything is already queued. If we are the
4690 * first packet, do inline processing else queue the
4691 * packet and do the drain.
4692 */
4693 if (ringp->s_ring_first == NULL) {
4694 /*
4695 * Fast-path, ok to process and nothing queued.
4696 */
4697 ringp->s_ring_run = curthread;
4698 ringp->s_ring_state |= (S_RING_PROC);
4699
4700 mutex_exit(&ringp->s_ring_lock);
4701
4702 /*
4703 * We are the chain of 1 packet so
4704 * go through this fast path.
4705 */
4706 ASSERT(mp_chain->b_next == NULL);
4707
4708 (*proc)(arg1, arg2, mp_chain, NULL);
4709
4710 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock));
4711 /*
4712 * If we have an SRS performing bandwidth
4713 * control then we need to decrement the size
4714 * and count so the SRS has an accurate count
4715 * of the data queued between the SRS and its
4716 * soft rings. We decrement the counters only
4717 * when the packet is processed by both the
4718 * SRS and the soft ring.
4719 */
4720 mutex_enter(&mac_srs->srs_lock);
4721 MAC_UPDATE_SRS_COUNT_LOCKED(mac_srs, cnt);
4722 MAC_UPDATE_SRS_SIZE_LOCKED(mac_srs, sz);
4723 mutex_exit(&mac_srs->srs_lock);
4724
4725 mutex_enter(&ringp->s_ring_lock);
4726 ringp->s_ring_run = NULL;
4727 ringp->s_ring_state &= ~S_RING_PROC;
4728 if (ringp->s_ring_state & S_RING_CLIENT_WAIT)
4729 cv_signal(&ringp->s_ring_client_cv);
4730
4731 if ((ringp->s_ring_first == NULL) ||
4732 (ringp->s_ring_state & S_RING_BLANK)) {
4733 /*
4734 * We processed a single packet inline
4735 * and nothing new has arrived or our
4736 * receiver doesn't want to receive
4737 * any packets. We are done.
4738 */
4739 mutex_exit(&ringp->s_ring_lock);
4740 return;
4741 }
4742 } else {
4743 SOFT_RING_ENQUEUE_CHAIN(ringp,
4744 mp_chain, tail, cnt, sz);
4745 }
4746
4747 /*
4748 * We are here because either we couldn't do inline
4749 * processing (because something was already
4750 * queued), or we had a chain of more than one
4751 * packet, or something else arrived after we were
4752 * done with inline processing.
4753 */
4754 ASSERT(MUTEX_HELD(&ringp->s_ring_lock));
4755 ASSERT(ringp->s_ring_first != NULL);
4756
4757 ringp->s_ring_drain_func(ringp);
4758 mutex_exit(&ringp->s_ring_lock);
4759 return;
4760 } else {
4761 /* ST_RING_WORKER_ONLY case */
4762 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz);
4763 mac_soft_ring_worker_wakeup(ringp);
4764 mutex_exit(&ringp->s_ring_lock);
4765 }
4766 }
4767
4768 /*
4769 * TX SOFTRING RELATED FUNCTIONS
4770 *
4771 * These functions really belong in mac_soft_ring.c and here for
4772 * a short period.
4773 */
4774
4775 #define TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp, tail, cnt, sz) { \
4776 ASSERT(MUTEX_HELD(&ringp->s_ring_lock)); \
4777 ringp->s_ring_state |= S_RING_ENQUEUED; \
4778 SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz); \
4779 }
4780
4781 /*
4782 * mac_tx_sring_queued
4783 *
4784 * When we are out of transmit descriptors and we already have a
4785 * queue that exceeds hiwat (or the client called us with
4786 * MAC_TX_NO_ENQUEUE or MAC_DROP_ON_NO_DESC flag), return the
4787 * soft ring pointer as the opaque cookie for the client enable
4788 * flow control.
4789 */
4790 static mac_tx_cookie_t
mac_tx_sring_enqueue(mac_soft_ring_t * ringp,mblk_t * mp_chain,uint16_t flag,mblk_t ** ret_mp)4791 mac_tx_sring_enqueue(mac_soft_ring_t *ringp, mblk_t *mp_chain, uint16_t flag,
4792 mblk_t **ret_mp)
4793 {
4794 int cnt;
4795 size_t sz;
4796 mblk_t *tail;
4797 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set;
4798 mac_tx_cookie_t cookie = 0;
4799 boolean_t wakeup_worker = B_TRUE;
4800
4801 ASSERT(MUTEX_HELD(&ringp->s_ring_lock));
4802 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz);
4803 if (flag & MAC_DROP_ON_NO_DESC) {
4804 mac_drop_chain(mp_chain, "Tx softring no desc");
4805 /* increment freed stats */
4806 ringp->s_ring_drops += cnt;
4807 cookie = (mac_tx_cookie_t)ringp;
4808 } else {
4809 if (ringp->s_ring_first != NULL)
4810 wakeup_worker = B_FALSE;
4811
4812 if (flag & MAC_TX_NO_ENQUEUE) {
4813 /*
4814 * If QUEUED is not set, queue the packet
4815 * and let mac_tx_soft_ring_drain() set
4816 * the TX_BLOCKED bit for the reasons
4817 * explained above. Otherwise, return the
4818 * mblks.
4819 */
4820 if (wakeup_worker) {
4821 TX_SOFT_RING_ENQUEUE_CHAIN(ringp,
4822 mp_chain, tail, cnt, sz);
4823 } else {
4824 ringp->s_ring_state |= S_RING_WAKEUP_CLIENT;
4825 cookie = (mac_tx_cookie_t)ringp;
4826 *ret_mp = mp_chain;
4827 }
4828 } else {
4829 boolean_t enqueue = B_TRUE;
4830
4831 if (ringp->s_ring_count > ringp->s_ring_tx_hiwat) {
4832 /*
4833 * flow-controlled. Store ringp in cookie
4834 * so that it can be returned as
4835 * mac_tx_cookie_t to client
4836 */
4837 ringp->s_ring_state |= S_RING_TX_HIWAT;
4838 cookie = (mac_tx_cookie_t)ringp;
4839 ringp->s_ring_hiwat_cnt++;
4840 if (ringp->s_ring_count >
4841 ringp->s_ring_tx_max_q_cnt) {
4842 /* increment freed stats */
4843 ringp->s_ring_drops += cnt;
4844 /*
4845 * b_prev may be set to the fanout hint
4846 * hence can't use freemsg directly
4847 */
4848 mac_drop_chain(mp_chain,
4849 "Tx softring max queue");
4850 DTRACE_PROBE1(tx_queued_hiwat,
4851 mac_soft_ring_t *, ringp);
4852 enqueue = B_FALSE;
4853 }
4854 }
4855 if (enqueue) {
4856 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain,
4857 tail, cnt, sz);
4858 }
4859 }
4860 if (wakeup_worker)
4861 cv_signal(&ringp->s_ring_async);
4862 }
4863 return (cookie);
4864 }
4865
4866
4867 /*
4868 * mac_tx_soft_ring_process
4869 *
4870 * This routine is called when fanning out outgoing traffic among
4871 * multipe Tx rings.
4872 * Note that a soft ring is associated with a h/w Tx ring.
4873 */
4874 mac_tx_cookie_t
mac_tx_soft_ring_process(mac_soft_ring_t * ringp,mblk_t * mp_chain,uint16_t flag,mblk_t ** ret_mp)4875 mac_tx_soft_ring_process(mac_soft_ring_t *ringp, mblk_t *mp_chain,
4876 uint16_t flag, mblk_t **ret_mp)
4877 {
4878 mac_soft_ring_set_t *mac_srs = ringp->s_ring_set;
4879 int cnt;
4880 size_t sz;
4881 mblk_t *tail;
4882 mac_tx_cookie_t cookie = 0;
4883
4884 ASSERT(ringp != NULL);
4885 ASSERT(mp_chain != NULL);
4886 ASSERT(MUTEX_NOT_HELD(&ringp->s_ring_lock));
4887 /*
4888 * The following modes can come here: SRS_TX_BW_FANOUT,
4889 * SRS_TX_FANOUT, SRS_TX_AGGR, SRS_TX_BW_AGGR.
4890 */
4891 ASSERT(MAC_TX_SOFT_RINGS(mac_srs));
4892 ASSERT(mac_srs->srs_tx.st_mode == SRS_TX_FANOUT ||
4893 mac_srs->srs_tx.st_mode == SRS_TX_BW_FANOUT ||
4894 mac_srs->srs_tx.st_mode == SRS_TX_AGGR ||
4895 mac_srs->srs_tx.st_mode == SRS_TX_BW_AGGR);
4896
4897 if (ringp->s_ring_type & ST_RING_WORKER_ONLY) {
4898 /* Serialization mode */
4899
4900 mutex_enter(&ringp->s_ring_lock);
4901 if (ringp->s_ring_count > ringp->s_ring_tx_hiwat) {
4902 cookie = mac_tx_sring_enqueue(ringp, mp_chain,
4903 flag, ret_mp);
4904 mutex_exit(&ringp->s_ring_lock);
4905 return (cookie);
4906 }
4907 MAC_COUNT_CHAIN(mac_srs, mp_chain, tail, cnt, sz);
4908 TX_SOFT_RING_ENQUEUE_CHAIN(ringp, mp_chain, tail, cnt, sz);
4909 if (ringp->s_ring_state & (S_RING_BLOCK | S_RING_PROC)) {
4910 /*
4911 * If ring is blocked due to lack of Tx
4912 * descs, just return. Worker thread
4913 * will get scheduled when Tx desc's
4914 * become available.
4915 */
4916 mutex_exit(&ringp->s_ring_lock);
4917 return (cookie);
4918 }
4919 mac_soft_ring_worker_wakeup(ringp);
4920 mutex_exit(&ringp->s_ring_lock);
4921 return (cookie);
4922 } else {
4923 /* Default fanout mode */
4924 /*
4925 * S_RING_BLOCKED is set when underlying NIC runs
4926 * out of Tx descs and messages start getting
4927 * queued. It won't get reset until
4928 * tx_srs_drain() completely drains out the
4929 * messages.
4930 */
4931 mac_tx_stats_t stats;
4932
4933 if (ringp->s_ring_state & S_RING_ENQUEUED) {
4934 /* Tx descs/resources not available */
4935 mutex_enter(&ringp->s_ring_lock);
4936 if (ringp->s_ring_state & S_RING_ENQUEUED) {
4937 cookie = mac_tx_sring_enqueue(ringp, mp_chain,
4938 flag, ret_mp);
4939 mutex_exit(&ringp->s_ring_lock);
4940 return (cookie);
4941 }
4942 /*
4943 * While we were computing mblk count, the
4944 * flow control condition got relieved.
4945 * Continue with the transmission.
4946 */
4947 mutex_exit(&ringp->s_ring_lock);
4948 }
4949
4950 mp_chain = mac_tx_send(ringp->s_ring_tx_arg1,
4951 ringp->s_ring_tx_arg2, mp_chain, &stats);
4952
4953 /*
4954 * Multiple threads could be here sending packets.
4955 * Under such conditions, it is not possible to
4956 * automically set S_RING_BLOCKED bit to indicate
4957 * out of tx desc condition. To atomically set
4958 * this, we queue the returned packet and do
4959 * the setting of S_RING_BLOCKED in
4960 * mac_tx_soft_ring_drain().
4961 */
4962 if (mp_chain != NULL) {
4963 mutex_enter(&ringp->s_ring_lock);
4964 cookie =
4965 mac_tx_sring_enqueue(ringp, mp_chain, flag, ret_mp);
4966 mutex_exit(&ringp->s_ring_lock);
4967 return (cookie);
4968 }
4969 SRS_TX_STATS_UPDATE(mac_srs, &stats);
4970 SOFTRING_TX_STATS_UPDATE(ringp, &stats);
4971
4972 return (0);
4973 }
4974 }
4975