From a723406c4aeedb9dc5d54fb81130d13c757f41bc Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 28 Feb 2007 20:11:25 -0800 Subject: [PATCH] [PATCH] md: RAID6: clean up CPUID and FPU enter/exit code - Use kernel_fpu_begin() and kernel_fpu_end() - Use boot_cpu_has() for feature testing even in userspace Signed-off-by: H. Peter Anvin Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/raid6mmx.c | 16 +-- drivers/md/raid6sse1.c | 17 +--- drivers/md/raid6sse2.c | 22 ++--- drivers/md/raid6x86.h | 218 ++++------------------------------------- 4 files changed, 32 insertions(+), 241 deletions(-) diff --git a/drivers/md/raid6mmx.c b/drivers/md/raid6mmx.c index 359157aaf9..6181a5a336 100644 --- a/drivers/md/raid6mmx.c +++ b/drivers/md/raid6mmx.c @@ -30,14 +30,8 @@ const struct raid6_mmx_constants { static int raid6_have_mmx(void) { -#ifdef __KERNEL__ /* Not really "boot_cpu" but "all_cpus" */ return boot_cpu_has(X86_FEATURE_MMX); -#else - /* User space test code */ - u32 features = cpuid_features(); - return ( (features & (1<<23)) == (1<<23) ); -#endif } /* @@ -48,13 +42,12 @@ static void raid6_mmx1_gen_syndrome(int disks, size_t bytes, void **ptrs) u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; - raid6_mmx_save_t sa; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ - raid6_before_mmx(&sa); + kernel_fpu_begin(); asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d)); asm volatile("pxor %mm5,%mm5"); /* Zero temp */ @@ -78,7 +71,7 @@ static void raid6_mmx1_gen_syndrome(int disks, size_t bytes, void **ptrs) asm volatile("pxor %mm4,%mm4"); } - raid6_after_mmx(&sa); + kernel_fpu_end(); } const struct raid6_calls raid6_mmxx1 = { @@ -96,13 +89,12 @@ static void raid6_mmx2_gen_syndrome(int disks, size_t bytes, void **ptrs) u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; - raid6_mmx_save_t sa; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ - raid6_before_mmx(&sa); + kernel_fpu_begin(); asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d)); asm volatile("pxor %mm5,%mm5"); /* Zero temp */ @@ -137,7 +129,7 @@ static void raid6_mmx2_gen_syndrome(int disks, size_t bytes, void **ptrs) asm volatile("movq %%mm6,%0" : "=m" (q[d+8])); } - raid6_after_mmx(&sa); + kernel_fpu_end(); } const struct raid6_calls raid6_mmxx2 = { diff --git a/drivers/md/raid6sse1.c b/drivers/md/raid6sse1.c index f7e7859f71..f0a1ba8f40 100644 --- a/drivers/md/raid6sse1.c +++ b/drivers/md/raid6sse1.c @@ -33,16 +33,10 @@ extern const struct raid6_mmx_constants { static int raid6_have_sse1_or_mmxext(void) { -#ifdef __KERNEL__ /* Not really boot_cpu but "all_cpus" */ return boot_cpu_has(X86_FEATURE_MMX) && (boot_cpu_has(X86_FEATURE_XMM) || boot_cpu_has(X86_FEATURE_MMXEXT)); -#else - /* User space test code - this incorrectly breaks on some Athlons */ - u32 features = cpuid_features(); - return ( (features & (5<<23)) == (5<<23) ); -#endif } /* @@ -53,14 +47,12 @@ static void raid6_sse11_gen_syndrome(int disks, size_t bytes, void **ptrs) u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; - raid6_mmx_save_t sa; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ - /* This is really MMX code, not SSE */ - raid6_before_mmx(&sa); + kernel_fpu_begin(); asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d)); asm volatile("pxor %mm5,%mm5"); /* Zero temp */ @@ -94,8 +86,8 @@ static void raid6_sse11_gen_syndrome(int disks, size_t bytes, void **ptrs) asm volatile("movntq %%mm4,%0" : "=m" (q[d])); } - raid6_after_mmx(&sa); asm volatile("sfence" : : : "memory"); + kernel_fpu_end(); } const struct raid6_calls raid6_sse1x1 = { @@ -113,13 +105,12 @@ static void raid6_sse12_gen_syndrome(int disks, size_t bytes, void **ptrs) u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; - raid6_mmx_save_t sa; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ - raid6_before_mmx(&sa); + kernel_fpu_begin(); asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d)); asm volatile("pxor %mm5,%mm5"); /* Zero temp */ @@ -157,8 +148,8 @@ static void raid6_sse12_gen_syndrome(int disks, size_t bytes, void **ptrs) asm volatile("movntq %%mm6,%0" : "=m" (q[d+8])); } - raid6_after_mmx(&sa); asm volatile("sfence" : :: "memory"); + kernel_fpu_end(); } const struct raid6_calls raid6_sse1x2 = { diff --git a/drivers/md/raid6sse2.c b/drivers/md/raid6sse2.c index b3aa7fe087..0f019762a7 100644 --- a/drivers/md/raid6sse2.c +++ b/drivers/md/raid6sse2.c @@ -30,17 +30,11 @@ static const struct raid6_sse_constants { static int raid6_have_sse2(void) { -#ifdef __KERNEL__ /* Not really boot_cpu but "all_cpus" */ return boot_cpu_has(X86_FEATURE_MMX) && boot_cpu_has(X86_FEATURE_FXSR) && boot_cpu_has(X86_FEATURE_XMM) && boot_cpu_has(X86_FEATURE_XMM2); -#else - /* User space test code */ - u32 features = cpuid_features(); - return ( (features & (15<<23)) == (15<<23) ); -#endif } /* @@ -51,13 +45,12 @@ static void raid6_sse21_gen_syndrome(int disks, size_t bytes, void **ptrs) u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; - raid6_sse_save_t sa; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ - raid6_before_sse2(&sa); + kernel_fpu_begin(); asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0])); asm volatile("pxor %xmm5,%xmm5"); /* Zero temp */ @@ -93,8 +86,8 @@ static void raid6_sse21_gen_syndrome(int disks, size_t bytes, void **ptrs) asm volatile("pxor %xmm4,%xmm4"); } - raid6_after_sse2(&sa); asm volatile("sfence" : : : "memory"); + kernel_fpu_end(); } const struct raid6_calls raid6_sse2x1 = { @@ -112,13 +105,12 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs) u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; - raid6_sse_save_t sa; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ - raid6_before_sse2(&sa); + kernel_fpu_begin(); asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0])); asm volatile("pxor %xmm5,%xmm5"); /* Zero temp */ @@ -156,8 +148,8 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs) asm volatile("movntdq %%xmm6,%0" : "=m" (q[d+16])); } - raid6_after_sse2(&sa); asm volatile("sfence" : : : "memory"); + kernel_fpu_end(); } const struct raid6_calls raid6_sse2x2 = { @@ -179,13 +171,12 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs) u8 **dptr = (u8 **)ptrs; u8 *p, *q; int d, z, z0; - raid6_sse16_save_t sa; z0 = disks - 3; /* Highest data disk */ p = dptr[z0+1]; /* XOR parity */ q = dptr[z0+2]; /* RS syndrome */ - raid6_before_sse16(&sa); + kernel_fpu_begin(); asm volatile("movdqa %0,%%xmm0" :: "m" (raid6_sse_constants.x1d[0])); asm volatile("pxor %xmm2,%xmm2"); /* P[0] */ @@ -256,8 +247,9 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs) asm volatile("movntdq %%xmm14,%0" : "=m" (q[d+48])); asm volatile("pxor %xmm14,%xmm14"); } + asm volatile("sfence" : : : "memory"); - raid6_after_sse16(&sa); + kernel_fpu_end(); } const struct raid6_calls raid6_sse2x4 = { diff --git a/drivers/md/raid6x86.h b/drivers/md/raid6x86.h index 4cf20534fe..9111950414 100644 --- a/drivers/md/raid6x86.h +++ b/drivers/md/raid6x86.h @@ -21,224 +21,40 @@ #if defined(__i386__) || defined(__x86_64__) -#ifdef __x86_64__ - -typedef struct { - unsigned int fsave[27]; - unsigned long cr0; -} raid6_mmx_save_t __attribute__((aligned(16))); - -/* N.B.: For SSE we only save %xmm0-%xmm7 even for x86-64, since - the code doesn't know about the additional x86-64 registers */ -typedef struct { - unsigned int sarea[8*4+2]; - unsigned long cr0; -} raid6_sse_save_t __attribute__((aligned(16))); - -/* This is for x86-64-specific code which uses all 16 XMM registers */ -typedef struct { - unsigned int sarea[16*4+2]; - unsigned long cr0; -} raid6_sse16_save_t __attribute__((aligned(16))); - -/* On x86-64 the stack *SHOULD* be 16-byte aligned, but currently this - is buggy in the kernel and it's only 8-byte aligned in places, so - we need to do this anyway. Sigh. */ -#define SAREA(x) ((unsigned int *)((((unsigned long)&(x)->sarea)+15) & ~15)) - -#else /* __i386__ */ - -typedef struct { - unsigned int fsave[27]; - unsigned long cr0; -} raid6_mmx_save_t; - -/* On i386, the stack is only 8-byte aligned, but SSE requires 16-byte - alignment. The +3 is so we have the slack space to manually align - a properly-sized area correctly. */ -typedef struct { - unsigned int sarea[8*4+3]; - unsigned long cr0; -} raid6_sse_save_t; - -/* Find the 16-byte aligned save area */ -#define SAREA(x) ((unsigned int *)((((unsigned long)&(x)->sarea)+15) & ~15)) - -#endif - #ifdef __KERNEL__ /* Real code */ -/* Note: %cr0 is 32 bits on i386 and 64 bits on x86-64 */ - -static inline unsigned long raid6_get_fpu(void) -{ - unsigned long cr0; - - preempt_disable(); - asm volatile("mov %%cr0,%0 ; clts" : "=r" (cr0)); - return cr0; -} - -static inline void raid6_put_fpu(unsigned long cr0) -{ - asm volatile("mov %0,%%cr0" : : "r" (cr0)); - preempt_enable(); -} +#include #else /* Dummy code for user space testing */ -static inline unsigned long raid6_get_fpu(void) -{ - return 0xf00ba6; -} - -static inline void raid6_put_fpu(unsigned long cr0) -{ - (void)cr0; -} - -#endif - -static inline void raid6_before_mmx(raid6_mmx_save_t *s) -{ - s->cr0 = raid6_get_fpu(); - asm volatile("fsave %0 ; fwait" : "=m" (s->fsave[0])); -} - -static inline void raid6_after_mmx(raid6_mmx_save_t *s) -{ - asm volatile("frstor %0" : : "m" (s->fsave[0])); - raid6_put_fpu(s->cr0); -} - -static inline void raid6_before_sse(raid6_sse_save_t *s) -{ - unsigned int *rsa = SAREA(s); - - s->cr0 = raid6_get_fpu(); - - asm volatile("movaps %%xmm0,%0" : "=m" (rsa[0])); - asm volatile("movaps %%xmm1,%0" : "=m" (rsa[4])); - asm volatile("movaps %%xmm2,%0" : "=m" (rsa[8])); - asm volatile("movaps %%xmm3,%0" : "=m" (rsa[12])); - asm volatile("movaps %%xmm4,%0" : "=m" (rsa[16])); - asm volatile("movaps %%xmm5,%0" : "=m" (rsa[20])); - asm volatile("movaps %%xmm6,%0" : "=m" (rsa[24])); - asm volatile("movaps %%xmm7,%0" : "=m" (rsa[28])); -} - -static inline void raid6_after_sse(raid6_sse_save_t *s) -{ - unsigned int *rsa = SAREA(s); - - asm volatile("movaps %0,%%xmm0" : : "m" (rsa[0])); - asm volatile("movaps %0,%%xmm1" : : "m" (rsa[4])); - asm volatile("movaps %0,%%xmm2" : : "m" (rsa[8])); - asm volatile("movaps %0,%%xmm3" : : "m" (rsa[12])); - asm volatile("movaps %0,%%xmm4" : : "m" (rsa[16])); - asm volatile("movaps %0,%%xmm5" : : "m" (rsa[20])); - asm volatile("movaps %0,%%xmm6" : : "m" (rsa[24])); - asm volatile("movaps %0,%%xmm7" : : "m" (rsa[28])); - - raid6_put_fpu(s->cr0); -} - -static inline void raid6_before_sse2(raid6_sse_save_t *s) +static inline void kernel_fpu_begin(void) { - unsigned int *rsa = SAREA(s); - - s->cr0 = raid6_get_fpu(); - - asm volatile("movdqa %%xmm0,%0" : "=m" (rsa[0])); - asm volatile("movdqa %%xmm1,%0" : "=m" (rsa[4])); - asm volatile("movdqa %%xmm2,%0" : "=m" (rsa[8])); - asm volatile("movdqa %%xmm3,%0" : "=m" (rsa[12])); - asm volatile("movdqa %%xmm4,%0" : "=m" (rsa[16])); - asm volatile("movdqa %%xmm5,%0" : "=m" (rsa[20])); - asm volatile("movdqa %%xmm6,%0" : "=m" (rsa[24])); - asm volatile("movdqa %%xmm7,%0" : "=m" (rsa[28])); } -static inline void raid6_after_sse2(raid6_sse_save_t *s) +static inline void kernel_fpu_end(void) { - unsigned int *rsa = SAREA(s); - - asm volatile("movdqa %0,%%xmm0" : : "m" (rsa[0])); - asm volatile("movdqa %0,%%xmm1" : : "m" (rsa[4])); - asm volatile("movdqa %0,%%xmm2" : : "m" (rsa[8])); - asm volatile("movdqa %0,%%xmm3" : : "m" (rsa[12])); - asm volatile("movdqa %0,%%xmm4" : : "m" (rsa[16])); - asm volatile("movdqa %0,%%xmm5" : : "m" (rsa[20])); - asm volatile("movdqa %0,%%xmm6" : : "m" (rsa[24])); - asm volatile("movdqa %0,%%xmm7" : : "m" (rsa[28])); - - raid6_put_fpu(s->cr0); } -#ifdef __x86_64__ - -static inline void raid6_before_sse16(raid6_sse16_save_t *s) -{ - unsigned int *rsa = SAREA(s); - - s->cr0 = raid6_get_fpu(); +#define X86_FEATURE_MMX (0*32+23) /* Multimedia Extensions */ +#define X86_FEATURE_FXSR (0*32+24) /* FXSAVE and FXRSTOR instructions + * (fast save and restore) */ +#define X86_FEATURE_XMM (0*32+25) /* Streaming SIMD Extensions */ +#define X86_FEATURE_XMM2 (0*32+26) /* Streaming SIMD Extensions-2 */ +#define X86_FEATURE_MMXEXT (1*32+22) /* AMD MMX extensions */ - asm volatile("movdqa %%xmm0,%0" : "=m" (rsa[0])); - asm volatile("movdqa %%xmm1,%0" : "=m" (rsa[4])); - asm volatile("movdqa %%xmm2,%0" : "=m" (rsa[8])); - asm volatile("movdqa %%xmm3,%0" : "=m" (rsa[12])); - asm volatile("movdqa %%xmm4,%0" : "=m" (rsa[16])); - asm volatile("movdqa %%xmm5,%0" : "=m" (rsa[20])); - asm volatile("movdqa %%xmm6,%0" : "=m" (rsa[24])); - asm volatile("movdqa %%xmm7,%0" : "=m" (rsa[28])); - asm volatile("movdqa %%xmm8,%0" : "=m" (rsa[32])); - asm volatile("movdqa %%xmm9,%0" : "=m" (rsa[36])); - asm volatile("movdqa %%xmm10,%0" : "=m" (rsa[40])); - asm volatile("movdqa %%xmm11,%0" : "=m" (rsa[44])); - asm volatile("movdqa %%xmm12,%0" : "=m" (rsa[48])); - asm volatile("movdqa %%xmm13,%0" : "=m" (rsa[52])); - asm volatile("movdqa %%xmm14,%0" : "=m" (rsa[56])); - asm volatile("movdqa %%xmm15,%0" : "=m" (rsa[60])); -} - -static inline void raid6_after_sse16(raid6_sse16_save_t *s) +/* Should work well enough on modern CPUs for testing */ +static inline int boot_cpu_has(int flag) { - unsigned int *rsa = SAREA(s); + u32 eax = (flag >> 5) ? 0x80000001 : 1; + u32 edx; - asm volatile("movdqa %0,%%xmm0" : : "m" (rsa[0])); - asm volatile("movdqa %0,%%xmm1" : : "m" (rsa[4])); - asm volatile("movdqa %0,%%xmm2" : : "m" (rsa[8])); - asm volatile("movdqa %0,%%xmm3" : : "m" (rsa[12])); - asm volatile("movdqa %0,%%xmm4" : : "m" (rsa[16])); - asm volatile("movdqa %0,%%xmm5" : : "m" (rsa[20])); - asm volatile("movdqa %0,%%xmm6" : : "m" (rsa[24])); - asm volatile("movdqa %0,%%xmm7" : : "m" (rsa[28])); - asm volatile("movdqa %0,%%xmm8" : : "m" (rsa[32])); - asm volatile("movdqa %0,%%xmm9" : : "m" (rsa[36])); - asm volatile("movdqa %0,%%xmm10" : : "m" (rsa[40])); - asm volatile("movdqa %0,%%xmm11" : : "m" (rsa[44])); - asm volatile("movdqa %0,%%xmm12" : : "m" (rsa[48])); - asm volatile("movdqa %0,%%xmm13" : : "m" (rsa[52])); - asm volatile("movdqa %0,%%xmm14" : : "m" (rsa[56])); - asm volatile("movdqa %0,%%xmm15" : : "m" (rsa[60])); + asm volatile("cpuid" + : "+a" (eax), "=d" (edx) + : : "ecx", "ebx"); - raid6_put_fpu(s->cr0); + return (edx >> (flag & 31)) & 1; } -#endif /* __x86_64__ */ - -/* User space test hack */ -#ifndef __KERNEL__ -static inline int cpuid_features(void) -{ - u32 eax = 1; - u32 ebx, ecx, edx; - - asm volatile("cpuid" : - "+a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)); - - return edx; -} #endif /* ndef __KERNEL__ */ #endif -- 2.20.1