/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. * Copyright 2013 Joyent, Inc. All rights reserved. */ /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ /* All Rights Reserved */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static pri_t rt_init(id_t, int, classfuncs_t **); static struct sclass csw = { "RT", rt_init, 0 }; static struct modlsched modlsched = { &mod_schedops, "realtime scheduling class", &csw }; static struct modlinkage modlinkage = { MODREV_1, (void *)&modlsched, NULL }; int _init() { return (mod_install(&modlinkage)); } int _fini() { return (EBUSY); /* don't remove RT for now */ } int _info(struct modinfo *modinfop) { return (mod_info(&modlinkage, modinfop)); } /* * Class specific code for the real-time class */ /* * Extern declarations for variables defined in the rt master file */ #define RTMAXPRI 59 pri_t rt_maxpri = RTMAXPRI; /* maximum real-time priority */ rtdpent_t *rt_dptbl; /* real-time dispatcher parameter table */ /* * control flags (kparms->rt_cflags). */ #define RT_DOPRI 0x01 /* change priority */ #define RT_DOTQ 0x02 /* change RT time quantum */ #define RT_DOSIG 0x04 /* change RT time quantum signal */ static int rt_admin(caddr_t, cred_t *); static int rt_enterclass(kthread_t *, id_t, void *, cred_t *, void *); static int rt_fork(kthread_t *, kthread_t *, void *); static int rt_getclinfo(void *); static int rt_getclpri(pcpri_t *); static int rt_parmsin(void *); static int rt_parmsout(void *, pc_vaparms_t *); static int rt_vaparmsin(void *, pc_vaparms_t *); static int rt_vaparmsout(void *, pc_vaparms_t *); static int rt_parmsset(kthread_t *, void *, id_t, cred_t *); static int rt_donice(kthread_t *, cred_t *, int, int *); static int rt_doprio(kthread_t *, cred_t *, int, int *); static void rt_exitclass(void *); static int rt_canexit(kthread_t *, cred_t *); static void rt_forkret(kthread_t *, kthread_t *); static void rt_nullsys(); static void rt_parmsget(kthread_t *, void *); static void rt_preempt(kthread_t *); static void rt_setrun(kthread_t *); static void rt_tick(kthread_t *); static void rt_wakeup(kthread_t *); static pri_t rt_swapin(kthread_t *, int); static pri_t rt_swapout(kthread_t *, int); static pri_t rt_globpri(kthread_t *); static void rt_yield(kthread_t *); static int rt_alloc(void **, int); static void rt_free(void *); static void rt_change_priority(kthread_t *, rtproc_t *); static id_t rt_cid; /* real-time class ID */ static rtproc_t rt_plisthead; /* dummy rtproc at head of rtproc list */ static kmutex_t rt_dptblock; /* protects realtime dispatch table */ static kmutex_t rt_list_lock; /* protects RT thread list */ extern rtdpent_t *rt_getdptbl(void); static struct classfuncs rt_classfuncs = { /* class ops */ rt_admin, rt_getclinfo, rt_parmsin, rt_parmsout, rt_vaparmsin, rt_vaparmsout, rt_getclpri, rt_alloc, rt_free, /* thread ops */ rt_enterclass, rt_exitclass, rt_canexit, rt_fork, rt_forkret, rt_parmsget, rt_parmsset, rt_nullsys, /* stop */ rt_nullsys, /* exit */ rt_nullsys, /* active */ rt_nullsys, /* inactive */ rt_swapin, rt_swapout, rt_nullsys, /* trapret */ rt_preempt, rt_setrun, rt_nullsys, /* sleep */ rt_tick, rt_wakeup, rt_donice, rt_globpri, rt_nullsys, /* set_process_group */ rt_yield, rt_doprio, }; /* * Real-time class initialization. Called by dispinit() at boot time. * We can ignore the clparmsz argument since we know that the smallest * possible parameter buffer is big enough for us. */ /* ARGSUSED */ pri_t rt_init(id_t cid, int clparmsz, classfuncs_t **clfuncspp) { rt_dptbl = rt_getdptbl(); rt_cid = cid; /* Record our class ID */ /* * Initialize the rtproc list. */ rt_plisthead.rt_next = rt_plisthead.rt_prev = &rt_plisthead; /* * We're required to return a pointer to our classfuncs * structure and the highest global priority value we use. */ *clfuncspp = &rt_classfuncs; mutex_init(&rt_dptblock, NULL, MUTEX_DEFAULT, NULL); mutex_init(&rt_list_lock, NULL, MUTEX_DEFAULT, NULL); return (rt_dptbl[rt_maxpri].rt_globpri); } /* * Get or reset the rt_dptbl values per the user's request. */ /* ARGSUSED */ static int rt_admin(caddr_t uaddr, cred_t *reqpcredp) { rtadmin_t rtadmin; rtdpent_t *tmpdpp; size_t userdpsz; size_t rtdpsz; int i; if (get_udatamodel() == DATAMODEL_NATIVE) { if (copyin(uaddr, &rtadmin, sizeof (rtadmin_t))) return (EFAULT); } #ifdef _SYSCALL32_IMPL else { /* rtadmin struct from ILP32 callers */ rtadmin32_t rtadmin32; if (copyin(uaddr, &rtadmin32, sizeof (rtadmin32_t))) return (EFAULT); rtadmin.rt_dpents = (struct rtdpent *)(uintptr_t)rtadmin32.rt_dpents; rtadmin.rt_ndpents = rtadmin32.rt_ndpents; rtadmin.rt_cmd = rtadmin32.rt_cmd; } #endif /* _SYSCALL32_IMPL */ rtdpsz = (rt_maxpri + 1) * sizeof (rtdpent_t); switch (rtadmin.rt_cmd) { case RT_GETDPSIZE: rtadmin.rt_ndpents = rt_maxpri + 1; if (get_udatamodel() == DATAMODEL_NATIVE) { if (copyout(&rtadmin, uaddr, sizeof (rtadmin_t))) return (EFAULT); } #ifdef _SYSCALL32_IMPL else { /* return rtadmin struct to ILP32 callers */ rtadmin32_t rtadmin32; rtadmin32.rt_dpents = (caddr32_t)(uintptr_t)rtadmin.rt_dpents; rtadmin32.rt_ndpents = rtadmin.rt_ndpents; rtadmin32.rt_cmd = rtadmin.rt_cmd; if (copyout(&rtadmin32, uaddr, sizeof (rtadmin32_t))) return (EFAULT); } #endif /* _SYSCALL32_IMPL */ break; case RT_GETDPTBL: userdpsz = MIN(rtadmin.rt_ndpents * sizeof (rtdpent_t), rtdpsz); if (copyout(rt_dptbl, rtadmin.rt_dpents, userdpsz)) return (EFAULT); rtadmin.rt_ndpents = userdpsz / sizeof (rtdpent_t); if (get_udatamodel() == DATAMODEL_NATIVE) { if (copyout(&rtadmin, uaddr, sizeof (rtadmin_t))) return (EFAULT); } #ifdef _SYSCALL32_IMPL else { /* return rtadmin struct to ILP32 callers */ rtadmin32_t rtadmin32; rtadmin32.rt_dpents = (caddr32_t)(uintptr_t)rtadmin.rt_dpents; rtadmin32.rt_ndpents = rtadmin.rt_ndpents; rtadmin32.rt_cmd = rtadmin.rt_cmd; if (copyout(&rtadmin32, uaddr, sizeof (rtadmin32_t))) return (EFAULT); } #endif /* _SYSCALL32_IMPL */ break; case RT_SETDPTBL: /* * We require that the requesting process has sufficient * priveleges. We also require that the table supplied by * the user exactly match the current rt_dptbl in size. */ if (secpolicy_dispadm(reqpcredp) != 0) return (EPERM); if (rtadmin.rt_ndpents * sizeof (rtdpent_t) != rtdpsz) return (EINVAL); /* * We read the user supplied table into a temporary buffer * where the time quantum values are validated before * being copied to the rt_dptbl. */ tmpdpp = kmem_alloc(rtdpsz, KM_SLEEP); if (copyin(rtadmin.rt_dpents, tmpdpp, rtdpsz)) { kmem_free(tmpdpp, rtdpsz); return (EFAULT); } for (i = 0; i < rtadmin.rt_ndpents; i++) { /* * Validate the user supplied time quantum values. */ if (tmpdpp[i].rt_quantum <= 0 && tmpdpp[i].rt_quantum != RT_TQINF) { kmem_free(tmpdpp, rtdpsz); return (EINVAL); } } /* * Copy the user supplied values over the current rt_dptbl * values. The rt_globpri member is read-only so we don't * overwrite it. */ mutex_enter(&rt_dptblock); for (i = 0; i < rtadmin.rt_ndpents; i++) rt_dptbl[i].rt_quantum = tmpdpp[i].rt_quantum; mutex_exit(&rt_dptblock); kmem_free(tmpdpp, rtdpsz); break; default: return (EINVAL); } return (0); } /* * Allocate a real-time class specific proc structure and * initialize it with the parameters supplied. Also move thread * to specified real-time priority. */ /* ARGSUSED */ static int rt_enterclass(kthread_t *t, id_t cid, void *parmsp, cred_t *reqpcredp, void *bufp) { rtkparms_t *rtkparmsp = (rtkparms_t *)parmsp; rtproc_t *rtpp; /* * For a thread to enter the real-time class the thread * which initiates the request must be privileged. * This may have been checked previously but if our * caller passed us a credential structure we assume it * hasn't and we check it here. */ if (reqpcredp != NULL && secpolicy_setpriority(reqpcredp) != 0) return (EPERM); rtpp = (rtproc_t *)bufp; ASSERT(rtpp != NULL); /* * If this thread's lwp is swapped out, it will be brought in * when it is put onto the runqueue. * * Now, Initialize the rtproc structure. */ if (rtkparmsp == NULL) { /* * Use default values */ rtpp->rt_pri = 0; rtpp->rt_pquantum = rt_dptbl[0].rt_quantum; rtpp->rt_tqsignal = 0; } else { /* * Use supplied values */ if ((rtkparmsp->rt_cflags & RT_DOPRI) == 0) rtpp->rt_pri = 0; else rtpp->rt_pri = rtkparmsp->rt_pri; if (rtkparmsp->rt_tqntm == RT_TQINF) rtpp->rt_pquantum = RT_TQINF; else if (rtkparmsp->rt_tqntm == RT_TQDEF || (rtkparmsp->rt_cflags & RT_DOTQ) == 0) rtpp->rt_pquantum = rt_dptbl[rtpp->rt_pri].rt_quantum; else rtpp->rt_pquantum = rtkparmsp->rt_tqntm; if ((rtkparmsp->rt_cflags & RT_DOSIG) == 0) rtpp->rt_tqsignal = 0; else rtpp->rt_tqsignal = rtkparmsp->rt_tqsig; } rtpp->rt_flags = 0; rtpp->rt_tp = t; /* * Reset thread priority */ thread_lock(t); t->t_clfuncs = &(sclass[cid].cl_funcs->thread); t->t_cid = cid; t->t_cldata = (void *)rtpp; t->t_schedflag &= ~TS_RUNQMATCH; rt_change_priority(t, rtpp); thread_unlock(t); /* * Link new structure into rtproc list */ mutex_enter(&rt_list_lock); rtpp->rt_next = rt_plisthead.rt_next; rtpp->rt_prev = &rt_plisthead; rt_plisthead.rt_next->rt_prev = rtpp; rt_plisthead.rt_next = rtpp; mutex_exit(&rt_list_lock); return (0); } /* * Free rtproc structure of thread. */ static void rt_exitclass(void *procp) { rtproc_t *rtprocp = (rtproc_t *)procp; mutex_enter(&rt_list_lock); rtprocp->rt_prev->rt_next = rtprocp->rt_next; rtprocp->rt_next->rt_prev = rtprocp->rt_prev; mutex_exit(&rt_list_lock); kmem_free(rtprocp, sizeof (rtproc_t)); } /* * Allocate and initialize real-time class specific * proc structure for child. */ /* ARGSUSED */ static int rt_fork(kthread_t *t, kthread_t *ct, void *bufp) { rtproc_t *prtpp; rtproc_t *crtpp; ASSERT(MUTEX_HELD(&ttoproc(t)->p_lock)); /* * Initialize child's rtproc structure */ crtpp = (rtproc_t *)bufp; ASSERT(crtpp != NULL); prtpp = (rtproc_t *)t->t_cldata; thread_lock(t); crtpp->rt_timeleft = crtpp->rt_pquantum = prtpp->rt_pquantum; crtpp->rt_pri = prtpp->rt_pri; crtpp->rt_flags = prtpp->rt_flags & ~RTBACKQ; crtpp->rt_tqsignal = prtpp->rt_tqsignal; crtpp->rt_tp = ct; thread_unlock(t); /* * Link new structure into rtproc list */ ct->t_cldata = (void *)crtpp; mutex_enter(&rt_list_lock); crtpp->rt_next = rt_plisthead.rt_next; crtpp->rt_prev = &rt_plisthead; rt_plisthead.rt_next->rt_prev = crtpp; rt_plisthead.rt_next = crtpp; mutex_exit(&rt_list_lock); return (0); } /* * The child goes to the back of its dispatcher queue while the * parent continues to run after a real time thread forks. */ /* ARGSUSED */ static void rt_forkret(kthread_t *t, kthread_t *ct) { proc_t *pp = ttoproc(t); proc_t *cp = ttoproc(ct); ASSERT(t == curthread); ASSERT(MUTEX_HELD(&pidlock)); /* * Grab the child's p_lock before dropping pidlock to ensure * the process does not disappear before we set it running. */ mutex_enter(&cp->p_lock); mutex_exit(&pidlock); continuelwps(cp); mutex_exit(&cp->p_lock); mutex_enter(&pp->p_lock); continuelwps(pp); mutex_exit(&pp->p_lock); } /* * Get information about the real-time class into the buffer * pointed to by rtinfop. The maximum configured real-time * priority is the only information we supply. We ignore the * class and credential arguments because anyone can have this * information. */ /* ARGSUSED */ static int rt_getclinfo(void *infop) { rtinfo_t *rtinfop = (rtinfo_t *)infop; rtinfop->rt_maxpri = rt_maxpri; return (0); } /* * Return the user mode scheduling priority range. */ static int rt_getclpri(pcpri_t *pcprip) { pcprip->pc_clpmax = rt_maxpri; pcprip->pc_clpmin = 0; return (0); } static void rt_nullsys() { } /* ARGSUSED */ static int rt_canexit(kthread_t *t, cred_t *cred) { /* * Thread can always leave RT class */ return (0); } /* * Get the real-time scheduling parameters of the thread pointed to by * rtprocp into the buffer pointed to by rtkparmsp. */ static void rt_parmsget(kthread_t *t, void *parmsp) { rtproc_t *rtprocp = (rtproc_t *)t->t_cldata; rtkparms_t *rtkparmsp = (rtkparms_t *)parmsp; rtkparmsp->rt_pri = rtprocp->rt_pri; rtkparmsp->rt_tqntm = rtprocp->rt_pquantum; rtkparmsp->rt_tqsig = rtprocp->rt_tqsignal; } /* * Check the validity of the real-time parameters in the buffer * pointed to by rtprmsp. * We convert the rtparms buffer from the user supplied format to * our internal format (i.e. time quantum expressed in ticks). */ static int rt_parmsin(void *prmsp) { rtparms_t *rtprmsp = (rtparms_t *)prmsp; longlong_t ticks; uint_t cflags; /* * First check the validity of parameters and convert * the buffer to kernel format. */ if ((rtprmsp->rt_pri < 0 || rtprmsp->rt_pri > rt_maxpri) && rtprmsp->rt_pri != RT_NOCHANGE) return (EINVAL); cflags = (rtprmsp->rt_pri != RT_NOCHANGE ? RT_DOPRI : 0); if ((rtprmsp->rt_tqsecs == 0 && rtprmsp->rt_tqnsecs == 0) || rtprmsp->rt_tqnsecs >= NANOSEC) return (EINVAL); if (rtprmsp->rt_tqnsecs != RT_NOCHANGE) cflags |= RT_DOTQ; if (rtprmsp->rt_tqnsecs >= 0) { if ((ticks = SEC_TO_TICK((longlong_t)rtprmsp->rt_tqsecs) + NSEC_TO_TICK_ROUNDUP(rtprmsp->rt_tqnsecs)) > INT_MAX) return (ERANGE); ((rtkparms_t *)rtprmsp)->rt_tqntm = (int)ticks; } else { if (rtprmsp->rt_tqnsecs != RT_NOCHANGE && rtprmsp->rt_tqnsecs != RT_TQINF && rtprmsp->rt_tqnsecs != RT_TQDEF) return (EINVAL); ((rtkparms_t *)rtprmsp)->rt_tqntm = rtprmsp->rt_tqnsecs; } ((rtkparms_t *)rtprmsp)->rt_cflags = cflags; return (0); } /* * Check the validity of the real-time parameters in the pc_vaparms_t * structure vaparmsp and put them in the buffer pointed to by rtprmsp. * pc_vaparms_t contains (key, value) pairs of parameter. * rt_vaparmsin() is the variable parameter version of rt_parmsin(). */ static int rt_vaparmsin(void *prmsp, pc_vaparms_t *vaparmsp) { uint_t secs = 0; uint_t cnt; int nsecs = 0; int priflag, secflag, nsecflag, sigflag; longlong_t ticks; rtkparms_t *rtprmsp = (rtkparms_t *)prmsp; pc_vaparm_t *vpp = &vaparmsp->pc_parms[0]; /* * First check the validity of parameters and convert them * from the user supplied format to the internal format. */ priflag = secflag = nsecflag = sigflag = 0; rtprmsp->rt_cflags = 0; if (vaparmsp->pc_vaparmscnt > PC_VAPARMCNT) return (EINVAL); for (cnt = 0; cnt < vaparmsp->pc_vaparmscnt; cnt++, vpp++) { switch (vpp->pc_key) { case RT_KY_PRI: if (priflag++) return (EINVAL); rtprmsp->rt_cflags |= RT_DOPRI; rtprmsp->rt_pri = (pri_t)vpp->pc_parm; if (rtprmsp->rt_pri < 0 || rtprmsp->rt_pri > rt_maxpri) return (EINVAL); break; case RT_KY_TQSECS: if (secflag++) return (EINVAL); rtprmsp->rt_cflags |= RT_DOTQ; secs = (uint_t)vpp->pc_parm; break; case RT_KY_TQNSECS: if (nsecflag++) return (EINVAL); rtprmsp->rt_cflags |= RT_DOTQ; nsecs = (int)vpp->pc_parm; break; case RT_KY_TQSIG: if (sigflag++) return (EINVAL); rtprmsp->rt_cflags |= RT_DOSIG; rtprmsp->rt_tqsig = (int)vpp->pc_parm; if (rtprmsp->rt_tqsig < 0 || rtprmsp->rt_tqsig >= NSIG) return (EINVAL); break; default: return (EINVAL); } } if (vaparmsp->pc_vaparmscnt == 0) { /* * Use default parameters. */ rtprmsp->rt_pri = 0; rtprmsp->rt_tqntm = RT_TQDEF; rtprmsp->rt_tqsig = 0; rtprmsp->rt_cflags = RT_DOPRI | RT_DOTQ | RT_DOSIG; } else if ((rtprmsp->rt_cflags & RT_DOTQ) != 0) { if ((secs == 0 && nsecs == 0) || nsecs >= NANOSEC) return (EINVAL); if (nsecs >= 0) { if ((ticks = SEC_TO_TICK((longlong_t)secs) + NSEC_TO_TICK_ROUNDUP(nsecs)) > INT_MAX) return (ERANGE); rtprmsp->rt_tqntm = (int)ticks; } else { if (nsecs != RT_TQINF && nsecs != RT_TQDEF) return (EINVAL); rtprmsp->rt_tqntm = nsecs; } } return (0); } /* * Do required processing on the real-time parameter buffer * before it is copied out to the user. * All we have to do is convert the buffer from kernel to user format * (i.e. convert time quantum from ticks to seconds-nanoseconds). */ /* ARGSUSED */ static int rt_parmsout(void *prmsp, pc_vaparms_t *vaparmsp) { rtkparms_t *rtkprmsp = (rtkparms_t *)prmsp; if (vaparmsp != NULL) return (0); if (rtkprmsp->rt_tqntm < 0) { /* * Quantum field set to special value (e.g. RT_TQINF) */ ((rtparms_t *)rtkprmsp)->rt_tqnsecs = rtkprmsp->rt_tqntm; ((rtparms_t *)rtkprmsp)->rt_tqsecs = 0; } else { /* Convert quantum from ticks to seconds-nanoseconds */ timestruc_t ts; TICK_TO_TIMESTRUC(rtkprmsp->rt_tqntm, &ts); ((rtparms_t *)rtkprmsp)->rt_tqsecs = ts.tv_sec; ((rtparms_t *)rtkprmsp)->rt_tqnsecs = ts.tv_nsec; } return (0); } /* * Copy all selected real-time class parameters to the user. * The parameters are specified by a key. */ static int rt_vaparmsout(void *prmsp, pc_vaparms_t *vaparmsp) { rtkparms_t *rtkprmsp = (rtkparms_t *)prmsp; timestruc_t ts; uint_t cnt; uint_t secs; int nsecs; int priflag, secflag, nsecflag, sigflag; pc_vaparm_t *vpp = &vaparmsp->pc_parms[0]; ASSERT(MUTEX_NOT_HELD(&curproc->p_lock)); priflag = secflag = nsecflag = sigflag = 0; if (vaparmsp->pc_vaparmscnt > PC_VAPARMCNT) return (EINVAL); if (rtkprmsp->rt_tqntm < 0) { /* * Quantum field set to special value (e.g. RT_TQINF). */ secs = 0; nsecs = rtkprmsp->rt_tqntm; } else { /* * Convert quantum from ticks to seconds-nanoseconds. */ TICK_TO_TIMESTRUC(rtkprmsp->rt_tqntm, &ts); secs = ts.tv_sec; nsecs = ts.tv_nsec; } for (cnt = 0; cnt < vaparmsp->pc_vaparmscnt; cnt++, vpp++) { switch (vpp->pc_key) { case RT_KY_PRI: if (priflag++) return (EINVAL); if (copyout(&rtkprmsp->rt_pri, (caddr_t)(uintptr_t)vpp->pc_parm, sizeof (pri_t))) return (EFAULT); break; case RT_KY_TQSECS: if (secflag++) return (EINVAL); if (copyout(&secs, (caddr_t)(uintptr_t)vpp->pc_parm, sizeof (uint_t))) return (EFAULT); break; case RT_KY_TQNSECS: if (nsecflag++) return (EINVAL); if (copyout(&nsecs, (caddr_t)(uintptr_t)vpp->pc_parm, sizeof (int))) return (EFAULT); break; case RT_KY_TQSIG: if (sigflag++) return (EINVAL); if (copyout(&rtkprmsp->rt_tqsig, (caddr_t)(uintptr_t)vpp->pc_parm, sizeof (int))) return (EFAULT); break; default: return (EINVAL); } } return (0); } /* * Set the scheduling parameters of the thread pointed to by rtprocp * to those specified in the buffer pointed to by rtkprmsp. * Note that the parameters are expected to be in kernel format * (i.e. time quantm expressed in ticks). Real time parameters copied * in from the user should be processed by rt_parmsin() before they are * passed to this function. */ static int rt_parmsset(kthread_t *tx, void *prmsp, id_t reqpcid, cred_t *reqpcredp) { rtkparms_t *rtkprmsp = (rtkparms_t *)prmsp; rtproc_t *rtpp = (rtproc_t *)tx->t_cldata; ASSERT(MUTEX_HELD(&(ttoproc(tx))->p_lock)); /* * Basic permissions enforced by generic kernel code * for all classes require that a thread attempting * to change the scheduling parameters of a target thread * be privileged or have a real or effective UID * matching that of the target thread. We are not * called unless these basic permission checks have * already passed. The real-time class requires in addition * that the requesting thread be real-time unless it is privileged. * This may also have been checked previously but if our caller * passes us a credential structure we assume it hasn't and * we check it here. */ if (reqpcredp != NULL && reqpcid != rt_cid && secpolicy_raisepriority(reqpcredp) != 0) return (EPERM); thread_lock(tx); if ((rtkprmsp->rt_cflags & RT_DOPRI) != 0) { rtpp->rt_pri = rtkprmsp->rt_pri; rt_change_priority(tx, rtpp); } if (rtkprmsp->rt_tqntm == RT_TQINF) rtpp->rt_pquantum = RT_TQINF; else if (rtkprmsp->rt_tqntm == RT_TQDEF) rtpp->rt_timeleft = rtpp->rt_pquantum = rt_dptbl[rtpp->rt_pri].rt_quantum; else if ((rtkprmsp->rt_cflags & RT_DOTQ) != 0) rtpp->rt_timeleft = rtpp->rt_pquantum = rtkprmsp->rt_tqntm; if ((rtkprmsp->rt_cflags & RT_DOSIG) != 0) rtpp->rt_tqsignal = rtkprmsp->rt_tqsig; thread_unlock(tx); return (0); } /* * Arrange for thread to be placed in appropriate location * on dispatcher queue. Runs at splhi() since the clock * interrupt can cause RTBACKQ to be set. */ static void rt_preempt(kthread_t *t) { rtproc_t *rtpp = (rtproc_t *)(t->t_cldata); klwp_t *lwp; ASSERT(THREAD_LOCK_HELD(t)); /* * If the state is user I allow swapping because I know I won't * be holding any locks. */ if ((lwp = curthread->t_lwp) != NULL && lwp->lwp_state == LWP_USER) t->t_schedflag &= ~TS_DONT_SWAP; if ((rtpp->rt_flags & RTBACKQ) != 0) { rtpp->rt_timeleft = rtpp->rt_pquantum; rtpp->rt_flags &= ~RTBACKQ; setbackdq(t); } else setfrontdq(t); } /* * Return the global priority associated with this rt_pri. */ static pri_t rt_globpri(kthread_t *t) { rtproc_t *rtprocp = (rtproc_t *)t->t_cldata; return (rt_dptbl[rtprocp->rt_pri].rt_globpri); } static void rt_setrun(kthread_t *t) { rtproc_t *rtpp = (rtproc_t *)(t->t_cldata); ASSERT(THREAD_LOCK_HELD(t)); rtpp->rt_timeleft = rtpp->rt_pquantum; rtpp->rt_flags &= ~RTBACKQ; setbackdq(t); } /* * Returns the priority of the thread, -1 if the thread is loaded or ineligible * for swapin. * * FX and RT threads are designed so that they don't swapout; however, it * is possible that while the thread is swapped out and in another class, it * can be changed to FX or RT. Since these threads should be swapped in as * soon as they're runnable, rt_swapin returns SHRT_MAX, and fx_swapin * returns SHRT_MAX - 1, so that it gives deference to any swapped out RT * threads. */ /* ARGSUSED */ static pri_t rt_swapin(kthread_t *t, int flags) { pri_t tpri = -1; ASSERT(THREAD_LOCK_HELD(t)); if (t->t_state == TS_RUN && (t->t_schedflag & TS_LOAD) == 0) { tpri = (pri_t)SHRT_MAX; } return (tpri); } /* * Return an effective priority for swapout. */ /* ARGSUSED */ static pri_t rt_swapout(kthread_t *t, int flags) { ASSERT(THREAD_LOCK_HELD(t)); return (-1); } /* * Check for time slice expiration (unless thread has infinite time * slice). If time slice has expired arrange for thread to be preempted * and placed on back of queue. */ static void rt_tick(kthread_t *t) { rtproc_t *rtpp = (rtproc_t *)(t->t_cldata); ASSERT(MUTEX_HELD(&(ttoproc(t))->p_lock)); thread_lock(t); if ((rtpp->rt_pquantum != RT_TQINF && --rtpp->rt_timeleft == 0) || (t->t_state == TS_ONPROC && DISP_MUST_SURRENDER(t))) { if (rtpp->rt_timeleft == 0 && rtpp->rt_tqsignal) { thread_unlock(t); sigtoproc(ttoproc(t), t, rtpp->rt_tqsignal); thread_lock(t); } rtpp->rt_flags |= RTBACKQ; cpu_surrender(t); } thread_unlock(t); } /* * Place the thread waking up on the dispatcher queue. */ static void rt_wakeup(kthread_t *t) { rtproc_t *rtpp = (rtproc_t *)(t->t_cldata); ASSERT(THREAD_LOCK_HELD(t)); rtpp->rt_timeleft = rtpp->rt_pquantum; rtpp->rt_flags &= ~RTBACKQ; setbackdq(t); } static void rt_yield(kthread_t *t) { rtproc_t *rtpp = (rtproc_t *)(t->t_cldata); ASSERT(t == curthread); ASSERT(THREAD_LOCK_HELD(t)); rtpp->rt_flags &= ~RTBACKQ; setbackdq(t); } /* ARGSUSED */ static int rt_donice(kthread_t *t, cred_t *cr, int incr, int *retvalp) { return (EINVAL); } /* * Increment the priority of the specified thread by incr and * return the new value in *retvalp. */ static int rt_doprio(kthread_t *t, cred_t *cr, int incr, int *retvalp) { int newpri; rtproc_t *rtpp = (rtproc_t *)(t->t_cldata); rtkparms_t rtkparms; /* If there's no change to the priority, just return current setting */ if (incr == 0) { *retvalp = rtpp->rt_pri; return (0); } newpri = rtpp->rt_pri + incr; if (newpri > rt_maxpri || newpri < 0) return (EINVAL); *retvalp = newpri; rtkparms.rt_pri = newpri; rtkparms.rt_tqntm = RT_NOCHANGE; rtkparms.rt_tqsig = 0; rtkparms.rt_cflags = RT_DOPRI; return (rt_parmsset(t, &rtkparms, rt_cid, cr)); } static int rt_alloc(void **p, int flag) { void *bufp; bufp = kmem_alloc(sizeof (rtproc_t), flag); if (bufp == NULL) { return (ENOMEM); } else { *p = bufp; return (0); } } static void rt_free(void *bufp) { if (bufp) kmem_free(bufp, sizeof (rtproc_t)); } static void rt_change_priority(kthread_t *t, rtproc_t *rtpp) { pri_t new_pri; ASSERT(THREAD_LOCK_HELD(t)); new_pri = rt_dptbl[rtpp->rt_pri].rt_globpri; t->t_cpri = rtpp->rt_pri; if (t == curthread || t->t_state == TS_ONPROC) { cpu_t *cp = t->t_disp_queue->disp_cpu; THREAD_CHANGE_PRI(t, new_pri); if (t == cp->cpu_dispthread) cp->cpu_dispatch_pri = DISP_PRIO(t); if (DISP_MUST_SURRENDER(t)) { rtpp->rt_flags |= RTBACKQ; cpu_surrender(t); } else { rtpp->rt_timeleft = rtpp->rt_pquantum; } } else { /* * When the priority of a thread is changed, * it may be necessary to adjust its position * on a sleep queue or dispatch queue. The * function thread_change_pri() accomplishes this. */ if (thread_change_pri(t, new_pri, 0)) { /* * The thread was on a run queue. * Reset its CPU timeleft. */ rtpp->rt_timeleft = rtpp->rt_pquantum; } else { rtpp->rt_flags |= RTBACKQ; } } }