xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/simd.h (revision fd440315)
1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright 2020 Joyent, Inc.
14  */
15 
16 #ifndef _SIMD_H
17 #define	_SIMD_H
18 
19 #if defined(__amd64__) || defined(__i386__)
20 
21 #define	kfpu_initialize(tsk)	do {} while (0)
22 #define	kfpu_init()		(0)
23 #define	kfpu_fini()		do {} while (0)
24 
25 #ifdef _KERNEL
26 #include <sys/x86_archext.h>
27 #include <sys/archsystm.h>
28 #include <sys/kfpu.h>
29 #include <sys/proc.h>
30 #include <sys/disp.h>
31 #include <sys/cpuvar.h>
32 
33 static inline int
kfpu_allowed(void)34 kfpu_allowed(void)
35 {
36 	extern int zfs_fpu_enabled;
37 
38 	return (zfs_fpu_enabled != 0 ? 1 : 0);
39 }
40 
41 static inline void
kfpu_begin(void)42 kfpu_begin(void)
43 {
44 	if (curthread->t_lwp != NULL && (curthread->t_procp->p_flag & SSYS)) {
45 		kernel_fpu_begin(NULL, KFPU_USE_LWP);
46 	} else {
47 		kpreempt_disable();
48 		kernel_fpu_begin(NULL, KFPU_NO_STATE);
49 	}
50 }
51 
52 static inline void
kfpu_end(void)53 kfpu_end(void)
54 {
55 	if (curthread->t_lwp != NULL && (curthread->t_procp->p_flag & SSYS)) {
56 		kernel_fpu_end(NULL, KFPU_USE_LWP);
57 	} else {
58 		kernel_fpu_end(NULL, KFPU_NO_STATE);
59 		kpreempt_enable();
60 	}
61 }
62 
63 /*
64  * Check if various vector instruction sets are available.
65  */
66 
67 static inline boolean_t
zfs_sse_available(void)68 zfs_sse_available(void)
69 {
70 	return (is_x86_feature(x86_featureset, X86FSET_SSE));
71 }
72 
73 static inline boolean_t
zfs_sse2_available(void)74 zfs_sse2_available(void)
75 {
76 	return (is_x86_feature(x86_featureset, X86FSET_SSE2));
77 }
78 
79 static inline boolean_t
zfs_sse3_available(void)80 zfs_sse3_available(void)
81 {
82 	return (is_x86_feature(x86_featureset, X86FSET_SSE3));
83 }
84 
85 static inline boolean_t
zfs_ssse3_available(void)86 zfs_ssse3_available(void)
87 {
88 	return (is_x86_feature(x86_featureset, X86FSET_SSSE3));
89 }
90 
91 static inline boolean_t
zfs_avx_available(void)92 zfs_avx_available(void)
93 {
94 	return (is_x86_feature(x86_featureset, X86FSET_AVX));
95 }
96 
97 static inline boolean_t
zfs_avx2_available(void)98 zfs_avx2_available(void)
99 {
100 	return (is_x86_feature(x86_featureset, X86FSET_AVX2));
101 }
102 
103 #else	/* ! _KERNEL */
104 
105 #include <sys/auxv.h>
106 #include <sys/auxv_386.h>
107 
108 #define	kfpu_allowed()		1
109 #define	kfpu_begin()		do {} while (0)
110 #define	kfpu_end()		do {} while (0)
111 
112 /*
113  * User-level check if various vector instruction sets are available.
114  */
115 
116 static inline boolean_t
zfs_sse_available(void)117 zfs_sse_available(void)
118 {
119 	uint32_t u = 0;
120 
121 	(void) getisax(&u, 1);
122 	return ((u & AV_386_SSE) != 0);
123 }
124 
125 static inline boolean_t
zfs_sse2_available(void)126 zfs_sse2_available(void)
127 {
128 	uint32_t u = 0;
129 
130 	(void) getisax(&u, 1);
131 	return ((u & AV_386_SSE2) != 0);
132 }
133 
134 static inline boolean_t
zfs_sse3_available(void)135 zfs_sse3_available(void)
136 {
137 	uint32_t u = 0;
138 
139 	(void) getisax(&u, 1);
140 	return ((u & AV_386_SSE3) != 0);
141 }
142 
143 static inline boolean_t
zfs_ssse3_available(void)144 zfs_ssse3_available(void)
145 {
146 	uint32_t u = 0;
147 
148 	(void) getisax(&u, 1);
149 	return ((u & AV_386_SSSE3) != 0);
150 }
151 
152 static inline boolean_t
zfs_avx_available(void)153 zfs_avx_available(void)
154 {
155 	uint_t u = 0;
156 
157 	(void) getisax(&u, 1);
158 	return ((u & AV_386_AVX) != 0);
159 }
160 
161 static inline boolean_t
zfs_avx2_available(void)162 zfs_avx2_available(void)
163 {
164 	uint32_t u[2] = { 0 };
165 
166 	(void) getisax((uint32_t *)&u, 2);
167 	return ((u[1] & AV_386_2_AVX2) != 0);
168 }
169 
170 #endif	/* _KERNEL */
171 
172 
173 #else
174 
175 /* Non-x86 CPUs currently always disallow kernel FPU support */
176 #define	kfpu_allowed()		0
177 #define	kfpu_initialize(tsk)	do {} while (0)
178 #define	kfpu_begin()		do {} while (0)
179 #define	kfpu_end()		do {} while (0)
180 #define	kfpu_init()		(0)
181 #define	kfpu_fini()		do {} while (0)
182 #endif
183 
184 #endif /* _SIMD_H */
185