From 751ba79cc552c146595cd439b21c4ff8998c3b69 Mon Sep 17 00:00:00 2001 From: Matt Brown Date: Fri, 4 Aug 2017 13:42:32 +1000 Subject: lib/raid6/altivec: Add vpermxor implementation for raid6 Q syndrome This patch uses the vpermxor instruction to optimise the raid6 Q syndrome. This instruction was made available with POWER8, ISA version 2.07. It allows for both vperm and vxor instructions to be done in a single instruction. This has been tested for correctness on a ppc64le vm with a basic RAID6 setup containing 5 drives. The performance benchmarks are from the raid6test in the /lib/raid6/test directory. These results are from an IBM Firestone machine with ppc64le architecture. The benchmark results show a 35% speed increase over the best existing algorithm for powerpc (altivec). The raid6test has also been run on a big-endian ppc64 vm to ensure it also works for big-endian architectures. Performance benchmarks: raid6: altivecx4 gen() 18773 MB/s raid6: altivecx8 gen() 19438 MB/s raid6: vpermxor4 gen() 25112 MB/s raid6: vpermxor8 gen() 26279 MB/s Signed-off-by: Matt Brown Reviewed-by: Daniel Axtens [mpe: Add VPERMXOR macro so we can build with old binutils] Signed-off-by: Michael Ellerman --- lib/raid6/.gitignore | 1 + lib/raid6/Makefile | 27 ++++++++++++- lib/raid6/algos.c | 4 ++ lib/raid6/test/Makefile | 17 +++++++- lib/raid6/vpermxor.uc | 105 ++++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 151 insertions(+), 3 deletions(-) create mode 100644 lib/raid6/vpermxor.uc (limited to 'lib/raid6') diff --git a/lib/raid6/.gitignore b/lib/raid6/.gitignore index f01b1cb04f91..3de0d8921286 100644 --- a/lib/raid6/.gitignore +++ b/lib/raid6/.gitignore @@ -4,3 +4,4 @@ int*.c tables.c neon?.c s390vx?.c +vpermxor*.c diff --git a/lib/raid6/Makefile b/lib/raid6/Makefile index 4add700ddfe3..21f59443e99e 100644 --- a/lib/raid6/Makefile +++ b/lib/raid6/Makefile @@ -5,7 +5,8 @@ raid6_pq-y += algos.o recov.o tables.o int1.o int2.o int4.o \ int8.o int16.o int32.o raid6_pq-$(CONFIG_X86) += recov_ssse3.o recov_avx2.o mmx.o sse1.o sse2.o avx2.o avx512.o recov_avx512.o -raid6_pq-$(CONFIG_ALTIVEC) += altivec1.o altivec2.o altivec4.o altivec8.o +raid6_pq-$(CONFIG_ALTIVEC) += altivec1.o altivec2.o altivec4.o altivec8.o \ + vpermxor1.o vpermxor2.o vpermxor4.o vpermxor8.o raid6_pq-$(CONFIG_KERNEL_MODE_NEON) += neon.o neon1.o neon2.o neon4.o neon8.o recov_neon.o recov_neon_inner.o raid6_pq-$(CONFIG_TILEGX) += tilegx8.o raid6_pq-$(CONFIG_S390) += s390vx8.o recov_s390xc.o @@ -91,6 +92,30 @@ $(obj)/altivec8.c: UNROLL := 8 $(obj)/altivec8.c: $(src)/altivec.uc $(src)/unroll.awk FORCE $(call if_changed,unroll) +CFLAGS_vpermxor1.o += $(altivec_flags) +targets += vpermxor1.c +$(obj)/vpermxor1.c: UNROLL := 1 +$(obj)/vpermxor1.c: $(src)/vpermxor.uc $(src)/unroll.awk FORCE + $(call if_changed,unroll) + +CFLAGS_vpermxor2.o += $(altivec_flags) +targets += vpermxor2.c +$(obj)/vpermxor2.c: UNROLL := 2 +$(obj)/vpermxor2.c: $(src)/vpermxor.uc $(src)/unroll.awk FORCE + $(call if_changed,unroll) + +CFLAGS_vpermxor4.o += $(altivec_flags) +targets += vpermxor4.c +$(obj)/vpermxor4.c: UNROLL := 4 +$(obj)/vpermxor4.c: $(src)/vpermxor.uc $(src)/unroll.awk FORCE + $(call if_changed,unroll) + +CFLAGS_vpermxor8.o += $(altivec_flags) +targets += vpermxor8.c +$(obj)/vpermxor8.c: UNROLL := 8 +$(obj)/vpermxor8.c: $(src)/vpermxor.uc $(src)/unroll.awk FORCE + $(call if_changed,unroll) + CFLAGS_neon1.o += $(NEON_FLAGS) targets += neon1.c $(obj)/neon1.c: UNROLL := 1 diff --git a/lib/raid6/algos.c b/lib/raid6/algos.c index 476994723258..b2e681018145 100644 --- a/lib/raid6/algos.c +++ b/lib/raid6/algos.c @@ -74,6 +74,10 @@ const struct raid6_calls * const raid6_algos[] = { &raid6_altivec2, &raid6_altivec4, &raid6_altivec8, + &raid6_vpermxor1, + &raid6_vpermxor2, + &raid6_vpermxor4, + &raid6_vpermxor8, #endif #if defined(CONFIG_TILEGX) &raid6_tilegx8, diff --git a/lib/raid6/test/Makefile b/lib/raid6/test/Makefile index be1010bdc435..ef6d0e00f189 100644 --- a/lib/raid6/test/Makefile +++ b/lib/raid6/test/Makefile @@ -48,7 +48,8 @@ else gcc -c -x c - >&/dev/null && \ rm ./-.o && echo yes) ifeq ($(HAS_ALTIVEC),yes) - OBJS += altivec1.o altivec2.o altivec4.o altivec8.o + OBJS += altivec1.o altivec2.o altivec4.o altivec8.o \ + vpermxor1.o vpermxor2.o vpermxor4.o vpermxor8.o endif endif ifeq ($(ARCH),tilegx) @@ -98,6 +99,18 @@ altivec4.c: altivec.uc ../unroll.awk altivec8.c: altivec.uc ../unroll.awk $(AWK) ../unroll.awk -vN=8 < altivec.uc > $@ +vpermxor1.c: vpermxor.uc ../unroll.awk + $(AWK) ../unroll.awk -vN=1 < vpermxor.uc > $@ + +vpermxor2.c: vpermxor.uc ../unroll.awk + $(AWK) ../unroll.awk -vN=2 < vpermxor.uc > $@ + +vpermxor4.c: vpermxor.uc ../unroll.awk + $(AWK) ../unroll.awk -vN=4 < vpermxor.uc > $@ + +vpermxor8.c: vpermxor.uc ../unroll.awk + $(AWK) ../unroll.awk -vN=8 < vpermxor.uc > $@ + int1.c: int.uc ../unroll.awk $(AWK) ../unroll.awk -vN=1 < int.uc > $@ @@ -123,7 +136,7 @@ tables.c: mktables ./mktables > tables.c clean: - rm -f *.o *.a mktables mktables.c *.uc int*.c altivec*.c neon*.c tables.c raid6test + rm -f *.o *.a mktables mktables.c *.uc int*.c altivec*.c vpermxor*.c neon*.c tables.c raid6test rm -f tilegx*.c spotless: clean diff --git a/lib/raid6/vpermxor.uc b/lib/raid6/vpermxor.uc new file mode 100644 index 000000000000..10475dc423c1 --- /dev/null +++ b/lib/raid6/vpermxor.uc @@ -0,0 +1,105 @@ +/* + * Copyright 2017, Matt Brown, IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * vpermxor$#.c + * + * Based on H. Peter Anvin's paper - The mathematics of RAID-6 + * + * $#-way unrolled portable integer math RAID-6 instruction set + * This file is postprocessed using unroll.awk + * + * vpermxor$#.c makes use of the vpermxor instruction to optimise the RAID6 Q + * syndrome calculations. + * This can be run on systems which have both Altivec and vpermxor instruction. + * + * This instruction was introduced in POWER8 - ISA v2.07. + */ + +#include +#ifdef CONFIG_ALTIVEC + +#include +#ifdef __KERNEL__ +#include +#include +#include +#endif + +typedef vector unsigned char unative_t; +#define NSIZE sizeof(unative_t) + +static const vector unsigned char gf_low = {0x1e, 0x1c, 0x1a, 0x18, 0x16, 0x14, + 0x12, 0x10, 0x0e, 0x0c, 0x0a, 0x08, + 0x06, 0x04, 0x02,0x00}; +static const vector unsigned char gf_high = {0xfd, 0xdd, 0xbd, 0x9d, 0x7d, 0x5d, + 0x3d, 0x1d, 0xe0, 0xc0, 0xa0, 0x80, + 0x60, 0x40, 0x20, 0x00}; + +static void noinline raid6_vpermxor$#_gen_syndrome_real(int disks, size_t bytes, + void **ptrs) +{ + u8 **dptr = (u8 **)ptrs; + u8 *p, *q; + int d, z, z0; + unative_t wp$$, wq$$, wd$$; + + z0 = disks - 3; /* Highest data disk */ + p = dptr[z0+1]; /* XOR parity */ + q = dptr[z0+2]; /* RS syndrome */ + + for (d = 0; d < bytes; d += NSIZE*$#) { + wp$$ = wq$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; + + for (z = z0-1; z>=0; z--) { + wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE]; + /* P syndrome */ + wp$$ = vec_xor(wp$$, wd$$); + + /* Q syndrome */ + asm(VPERMXOR(%0,%1,%2,%3):"=v"(wq$$):"v"(gf_high), "v"(gf_low), "v"(wq$$)); + wq$$ = vec_xor(wq$$, wd$$); + } + *(unative_t *)&p[d+NSIZE*$$] = wp$$; + *(unative_t *)&q[d+NSIZE*$$] = wq$$; + } +} + +static void raid6_vpermxor$#_gen_syndrome(int disks, size_t bytes, void **ptrs) +{ + preempt_disable(); + enable_kernel_altivec(); + + raid6_vpermxor$#_gen_syndrome_real(disks, bytes, ptrs); + + disable_kernel_altivec(); + preempt_enable(); +} + +int raid6_have_altivec_vpermxor(void); +#if $# == 1 +int raid6_have_altivec_vpermxor(void) +{ + /* Check if arch has both altivec and the vpermxor instructions */ +# ifdef __KERNEL__ + return (cpu_has_feature(CPU_FTR_ALTIVEC_COMP) && + cpu_has_feature(CPU_FTR_ARCH_207S)); +# else + return 1; +#endif + +} +#endif + +const struct raid6_calls raid6_vpermxor$# = { + raid6_vpermxor$#_gen_syndrome, + NULL, + raid6_have_altivec_vpermxor, + "vpermxor$#", + 0 +}; +#endif -- cgit v1.2.3-55-g7522 From aa9532d4899ff14e50de10d261b761d157cd2ae3 Mon Sep 17 00:00:00 2001 From: Matt Brown Date: Fri, 4 Aug 2017 13:42:33 +1000 Subject: lib/raid6: Build proper raid6test files on powerpc Previously the raid6 test Makefile did not build the POWER specific files (altivec and vpermxor). This patch fixes the bug, so that all appropriate files for powerpc are built. This patch also fixes the missing and mismatched ifdef statements to allow the altivec.uc file to be built correctly. Signed-off-by: Matt Brown Signed-off-by: Michael Ellerman --- lib/raid6/altivec.uc | 3 +++ lib/raid6/test/Makefile | 5 +++-- 2 files changed, 6 insertions(+), 2 deletions(-) (limited to 'lib/raid6') diff --git a/lib/raid6/altivec.uc b/lib/raid6/altivec.uc index 682aae8a1fef..d20ed0d11411 100644 --- a/lib/raid6/altivec.uc +++ b/lib/raid6/altivec.uc @@ -24,10 +24,13 @@ #include +#ifdef CONFIG_ALTIVEC + #include #ifdef __KERNEL__ # include # include +#endif /* __KERNEL__ */ /* * This is the C data type to use. We use a vector of diff --git a/lib/raid6/test/Makefile b/lib/raid6/test/Makefile index ef6d0e00f189..5050e270c06b 100644 --- a/lib/raid6/test/Makefile +++ b/lib/raid6/test/Makefile @@ -45,9 +45,10 @@ else ifeq ($(HAS_NEON),yes) CFLAGS += -DCONFIG_KERNEL_MODE_NEON=1 else HAS_ALTIVEC := $(shell printf '\#include \nvector int a;\n' |\ - gcc -c -x c - >&/dev/null && \ - rm ./-.o && echo yes) + gcc -c -x c - >/dev/null && rm ./-.o && echo yes) ifeq ($(HAS_ALTIVEC),yes) + CFLAGS += -I../../../arch/powerpc/include + CFLAGS += -DCONFIG_ALTIVEC OBJS += altivec1.o altivec2.o altivec4.o altivec8.o \ vpermxor1.o vpermxor2.o vpermxor4.o vpermxor8.o endif -- cgit v1.2.3-55-g7522