From a582564b24bec0443b5c5ff43ee6d1258f8bd658 Mon Sep 17 00:00:00 2001 From: Markus Stockhausen Date: Mon, 15 Dec 2014 12:57:05 +1100 Subject: [PATCH] md/raid6 algorithms: xor_syndrome() for SSE2 The second and (last) optimized XOR syndrome calculation. This version supports right and left side optimization. All CPUs with architecture older than Haswell will benefit from it. It should be noted that SSE2 movntdq kills performance for memory areas that are read and written simultaneously in chunks smaller than cache line size. So use movdqa instead for P/Q writes in sse21 and sse22 XOR functions. Signed-off-by: Markus Stockhausen Signed-off-by: NeilBrown --- lib/raid6/sse2.c | 230 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 227 insertions(+), 3 deletions(-) diff --git a/lib/raid6/sse2.c b/lib/raid6/sse2.c index 31acd59a0ef7..1d2276b007ee 100644 --- a/lib/raid6/sse2.c +++ b/lib/raid6/sse2.c @@ -88,9 +88,58 @@ static void raid6_sse21_gen_syndrome(int disks, size_t bytes, void **ptrs) kernel_fpu_end(); } + +static void raid6_sse21_xor_syndrome(int disks, int start, int stop, + size_t bytes, void **ptrs) + { + u8 **dptr = (u8 **)ptrs; + u8 *p, *q; + int d, z, z0; + + z0 = stop; /* P/Q right side optimization */ + p = dptr[disks-2]; /* XOR parity */ + q = dptr[disks-1]; /* RS syndrome */ + + kernel_fpu_begin(); + + asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0])); + + for ( d = 0 ; d < bytes ; d += 16 ) { + asm volatile("movdqa %0,%%xmm4" :: "m" (dptr[z0][d])); + asm volatile("movdqa %0,%%xmm2" : : "m" (p[d])); + asm volatile("pxor %xmm4,%xmm2"); + /* P/Q data pages */ + for ( z = z0-1 ; z >= start ; z-- ) { + asm volatile("pxor %xmm5,%xmm5"); + asm volatile("pcmpgtb %xmm4,%xmm5"); + asm volatile("paddb %xmm4,%xmm4"); + asm volatile("pand %xmm0,%xmm5"); + asm volatile("pxor %xmm5,%xmm4"); + asm volatile("movdqa %0,%%xmm5" :: "m" (dptr[z][d])); + asm volatile("pxor %xmm5,%xmm2"); + asm volatile("pxor %xmm5,%xmm4"); + } + /* P/Q left side optimization */ + for ( z = start-1 ; z >= 0 ; z-- ) { + asm volatile("pxor %xmm5,%xmm5"); + asm volatile("pcmpgtb %xmm4,%xmm5"); + asm volatile("paddb %xmm4,%xmm4"); + asm volatile("pand %xmm0,%xmm5"); + asm volatile("pxor %xmm5,%xmm4"); + } + asm volatile("pxor %0,%%xmm4" : : "m" (q[d])); + /* Don't use movntdq for r/w memory area < cache line */ + asm volatile("movdqa %%xmm4,%0" : "=m" (q[d])); + asm volatile("movdqa %%xmm2,%0" : "=m" (p[d])); + } + + asm volatile("sfence" : : : "memory"); + kernel_fpu_end(); +} + const struct raid6_calls raid6_sse2x1 = { raid6_sse21_gen_syndrome, - NULL, /* XOR not yet implemented */ + raid6_sse21_xor_syndrome, raid6_have_sse2, "sse2x1", 1 /* Has cache hints */ @@ -151,9 +200,76 @@ static void raid6_sse22_gen_syndrome(int disks, size_t bytes, void **ptrs) kernel_fpu_end(); } + static void raid6_sse22_xor_syndrome(int disks, int start, int stop, + size_t bytes, void **ptrs) + { + u8 **dptr = (u8 **)ptrs; + u8 *p, *q; + int d, z, z0; + + z0 = stop; /* P/Q right side optimization */ + p = dptr[disks-2]; /* XOR parity */ + q = dptr[disks-1]; /* RS syndrome */ + + kernel_fpu_begin(); + + asm volatile("movdqa %0,%%xmm0" : : "m" (raid6_sse_constants.x1d[0])); + + for ( d = 0 ; d < bytes ; d += 32 ) { + asm volatile("movdqa %0,%%xmm4" :: "m" (dptr[z0][d])); + asm volatile("movdqa %0,%%xmm6" :: "m" (dptr[z0][d+16])); + asm volatile("movdqa %0,%%xmm2" : : "m" (p[d])); + asm volatile("movdqa %0,%%xmm3" : : "m" (p[d+16])); + asm volatile("pxor %xmm4,%xmm2"); + asm volatile("pxor %xmm6,%xmm3"); + /* P/Q data pages */ + for ( z = z0-1 ; z >= start ; z-- ) { + asm volatile("pxor %xmm5,%xmm5"); + asm volatile("pxor %xmm7,%xmm7"); + asm volatile("pcmpgtb %xmm4,%xmm5"); + asm volatile("pcmpgtb %xmm6,%xmm7"); + asm volatile("paddb %xmm4,%xmm4"); + asm volatile("paddb %xmm6,%xmm6"); + asm volatile("pand %xmm0,%xmm5"); + asm volatile("pand %xmm0,%xmm7"); + asm volatile("pxor %xmm5,%xmm4"); + asm volatile("pxor %xmm7,%xmm6"); + asm volatile("movdqa %0,%%xmm5" :: "m" (dptr[z][d])); + asm volatile("movdqa %0,%%xmm7" :: "m" (dptr[z][d+16])); + asm volatile("pxor %xmm5,%xmm2"); + asm volatile("pxor %xmm7,%xmm3"); + asm volatile("pxor %xmm5,%xmm4"); + asm volatile("pxor %xmm7,%xmm6"); + } + /* P/Q left side optimization */ + for ( z = start-1 ; z >= 0 ; z-- ) { + asm volatile("pxor %xmm5,%xmm5"); + asm volatile("pxor %xmm7,%xmm7"); + asm volatile("pcmpgtb %xmm4,%xmm5"); + asm volatile("pcmpgtb %xmm6,%xmm7"); + asm volatile("paddb %xmm4,%xmm4"); + asm volatile("paddb %xmm6,%xmm6"); + asm volatile("pand %xmm0,%xmm5"); + asm volatile("pand %xmm0,%xmm7"); + asm volatile("pxor %xmm5,%xmm4"); + asm volatile("pxor %xmm7,%xmm6"); + } + asm volatile("pxor %0,%%xmm4" : : "m" (q[d])); + asm volatile("pxor %0,%%xmm6" : : "m" (q[d+16])); + /* Don't use movntdq for r/w memory area < cache line */ + asm volatile("movdqa %%xmm4,%0" : "=m" (q[d])); + asm volatile("movdqa %%xmm6,%0" : "=m" (q[d+16])); + asm volatile("movdqa %%xmm2,%0" : "=m" (p[d])); + asm volatile("movdqa %%xmm3,%0" : "=m" (p[d+16])); + } + + asm volatile("sfence" : : : "memory"); + kernel_fpu_end(); + } + const struct raid6_calls raid6_sse2x2 = { raid6_sse22_gen_syndrome, - NULL, /* XOR not yet implemented */ + raid6_sse22_xor_syndrome, raid6_have_sse2, "sse2x2", 1 /* Has cache hints */ @@ -250,9 +366,117 @@ static void raid6_sse24_gen_syndrome(int disks, size_t bytes, void **ptrs) kernel_fpu_end(); } + static void raid6_sse24_xor_syndrome(int disks, int start, int stop, + size_t bytes, void **ptrs) + { + u8 **dptr = (u8 **)ptrs; + u8 *p, *q; + int d, z, z0; + + z0 = stop; /* P/Q right side optimization */ + p = dptr[disks-2]; /* XOR parity */ + q = dptr[disks-1]; /* RS syndrome */ + + kernel_fpu_begin(); + + asm volatile("movdqa %0,%%xmm0" :: "m" (raid6_sse_constants.x1d[0])); + + for ( d = 0 ; d < bytes ; d += 64 ) { + asm volatile("movdqa %0,%%xmm4" :: "m" (dptr[z0][d])); + asm volatile("movdqa %0,%%xmm6" :: "m" (dptr[z0][d+16])); + asm volatile("movdqa %0,%%xmm12" :: "m" (dptr[z0][d+32])); + asm volatile("movdqa %0,%%xmm14" :: "m" (dptr[z0][d+48])); + asm volatile("movdqa %0,%%xmm2" : : "m" (p[d])); + asm volatile("movdqa %0,%%xmm3" : : "m" (p[d+16])); + asm volatile("movdqa %0,%%xmm10" : : "m" (p[d+32])); + asm volatile("movdqa %0,%%xmm11" : : "m" (p[d+48])); + asm volatile("pxor %xmm4,%xmm2"); + asm volatile("pxor %xmm6,%xmm3"); + asm volatile("pxor %xmm12,%xmm10"); + asm volatile("pxor %xmm14,%xmm11"); + /* P/Q data pages */ + for ( z = z0-1 ; z >= start ; z-- ) { + asm volatile("prefetchnta %0" :: "m" (dptr[z][d])); + asm volatile("prefetchnta %0" :: "m" (dptr[z][d+32])); + asm volatile("pxor %xmm5,%xmm5"); + asm volatile("pxor %xmm7,%xmm7"); + asm volatile("pxor %xmm13,%xmm13"); + asm volatile("pxor %xmm15,%xmm15"); + asm volatile("pcmpgtb %xmm4,%xmm5"); + asm volatile("pcmpgtb %xmm6,%xmm7"); + asm volatile("pcmpgtb %xmm12,%xmm13"); + asm volatile("pcmpgtb %xmm14,%xmm15"); + asm volatile("paddb %xmm4,%xmm4"); + asm volatile("paddb %xmm6,%xmm6"); + asm volatile("paddb %xmm12,%xmm12"); + asm volatile("paddb %xmm14,%xmm14"); + asm volatile("pand %xmm0,%xmm5"); + asm volatile("pand %xmm0,%xmm7"); + asm volatile("pand %xmm0,%xmm13"); + asm volatile("pand %xmm0,%xmm15"); + asm volatile("pxor %xmm5,%xmm4"); + asm volatile("pxor %xmm7,%xmm6"); + asm volatile("pxor %xmm13,%xmm12"); + asm volatile("pxor %xmm15,%xmm14"); + asm volatile("movdqa %0,%%xmm5" :: "m" (dptr[z][d])); + asm volatile("movdqa %0,%%xmm7" :: "m" (dptr[z][d+16])); + asm volatile("movdqa %0,%%xmm13" :: "m" (dptr[z][d+32])); + asm volatile("movdqa %0,%%xmm15" :: "m" (dptr[z][d+48])); + asm volatile("pxor %xmm5,%xmm2"); + asm volatile("pxor %xmm7,%xmm3"); + asm volatile("pxor %xmm13,%xmm10"); + asm volatile("pxor %xmm15,%xmm11"); + asm volatile("pxor %xmm5,%xmm4"); + asm volatile("pxor %xmm7,%xmm6"); + asm volatile("pxor %xmm13,%xmm12"); + asm volatile("pxor %xmm15,%xmm14"); + } + asm volatile("prefetchnta %0" :: "m" (q[d])); + asm volatile("prefetchnta %0" :: "m" (q[d+32])); + /* P/Q left side optimization */ + for ( z = start-1 ; z >= 0 ; z-- ) { + asm volatile("pxor %xmm5,%xmm5"); + asm volatile("pxor %xmm7,%xmm7"); + asm volatile("pxor %xmm13,%xmm13"); + asm volatile("pxor %xmm15,%xmm15"); + asm volatile("pcmpgtb %xmm4,%xmm5"); + asm volatile("pcmpgtb %xmm6,%xmm7"); + asm volatile("pcmpgtb %xmm12,%xmm13"); + asm volatile("pcmpgtb %xmm14,%xmm15"); + asm volatile("paddb %xmm4,%xmm4"); + asm volatile("paddb %xmm6,%xmm6"); + asm volatile("paddb %xmm12,%xmm12"); + asm volatile("paddb %xmm14,%xmm14"); + asm volatile("pand %xmm0,%xmm5"); + asm volatile("pand %xmm0,%xmm7"); + asm volatile("pand %xmm0,%xmm13"); + asm volatile("pand %xmm0,%xmm15"); + asm volatile("pxor %xmm5,%xmm4"); + asm volatile("pxor %xmm7,%xmm6"); + asm volatile("pxor %xmm13,%xmm12"); + asm volatile("pxor %xmm15,%xmm14"); + } + asm volatile("movntdq %%xmm2,%0" : "=m" (p[d])); + asm volatile("movntdq %%xmm3,%0" : "=m" (p[d+16])); + asm volatile("movntdq %%xmm10,%0" : "=m" (p[d+32])); + asm volatile("movntdq %%xmm11,%0" : "=m" (p[d+48])); + asm volatile("pxor %0,%%xmm4" : : "m" (q[d])); + asm volatile("pxor %0,%%xmm6" : : "m" (q[d+16])); + asm volatile("pxor %0,%%xmm12" : : "m" (q[d+32])); + asm volatile("pxor %0,%%xmm14" : : "m" (q[d+48])); + asm volatile("movntdq %%xmm4,%0" : "=m" (q[d])); + asm volatile("movntdq %%xmm6,%0" : "=m" (q[d+16])); + asm volatile("movntdq %%xmm12,%0" : "=m" (q[d+32])); + asm volatile("movntdq %%xmm14,%0" : "=m" (q[d+48])); + } + asm volatile("sfence" : : : "memory"); + kernel_fpu_end(); + } + + const struct raid6_calls raid6_sse2x4 = { raid6_sse24_gen_syndrome, - NULL, /* XOR not yet implemented */ + raid6_sse24_xor_syndrome, raid6_have_sse2, "sse2x4", 1 /* Has cache hints */ -- 2.20.1