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authorMartin Schwidefsky <schwidefsky@de.ibm.com>2016-08-23 13:30:24 +0200
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2016-08-29 11:05:04 +0200
commit474fd6e80fe529e9adeeb7ea9d4e5d6c4da0b7fe (patch)
treea5294d90e6e7205f26c4271cee49199be2a8addb /lib
parent8f149ea6e91534c3e0b4cfcd843323bd94273087 (diff)
downloadlinux-474fd6e80fe529e9adeeb7ea9d4e5d6c4da0b7fe.tar.bz2
RAID/s390: add SIMD implementation for raid6 gen/xor
Using vector registers is slightly faster: raid6: vx128x8 gen() 19705 MB/s raid6: vx128x8 xor() 11886 MB/s raid6: using algorithm vx128x8 gen() 19705 MB/s raid6: .... xor() 11886 MB/s, rmw enabled vs the software algorithms: raid6: int64x1 gen() 3018 MB/s raid6: int64x1 xor() 1429 MB/s raid6: int64x2 gen() 4661 MB/s raid6: int64x2 xor() 3143 MB/s raid6: int64x4 gen() 5392 MB/s raid6: int64x4 xor() 3509 MB/s raid6: int64x8 gen() 4441 MB/s raid6: int64x8 xor() 3207 MB/s raid6: using algorithm int64x4 gen() 5392 MB/s raid6: .... xor() 3509 MB/s, rmw enabled Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'lib')
-rw-r--r--lib/raid6/.gitignore1
-rw-r--r--lib/raid6/Makefile6
-rw-r--r--lib/raid6/algos.c3
-rw-r--r--lib/raid6/s390vx.uc168
4 files changed, 178 insertions, 0 deletions
diff --git a/lib/raid6/.gitignore b/lib/raid6/.gitignore
index 0a7e494b2bcd..f01b1cb04f91 100644
--- a/lib/raid6/.gitignore
+++ b/lib/raid6/.gitignore
@@ -3,3 +3,4 @@ altivec*.c
int*.c
tables.c
neon?.c
+s390vx?.c
diff --git a/lib/raid6/Makefile b/lib/raid6/Makefile
index 3b10a48fa040..667b9607f8c0 100644
--- a/lib/raid6/Makefile
+++ b/lib/raid6/Makefile
@@ -7,6 +7,7 @@ raid6_pq-$(CONFIG_X86) += recov_ssse3.o recov_avx2.o mmx.o sse1.o sse2.o avx2.o
raid6_pq-$(CONFIG_ALTIVEC) += altivec1.o altivec2.o altivec4.o altivec8.o
raid6_pq-$(CONFIG_KERNEL_MODE_NEON) += neon.o neon1.o neon2.o neon4.o neon8.o
raid6_pq-$(CONFIG_TILEGX) += tilegx8.o
+raid6_pq-$(CONFIG_S390) += s390vx8.o
hostprogs-y += mktables
@@ -116,6 +117,11 @@ $(obj)/tilegx8.c: UNROLL := 8
$(obj)/tilegx8.c: $(src)/tilegx.uc $(src)/unroll.awk FORCE
$(call if_changed,unroll)
+targets += s390vx8.c
+$(obj)/s390vx8.c: UNROLL := 8
+$(obj)/s390vx8.c: $(src)/s390vx.uc $(src)/unroll.awk FORCE
+ $(call if_changed,unroll)
+
quiet_cmd_mktable = TABLE $@
cmd_mktable = $(obj)/mktables > $@ || ( rm -f $@ && exit 1 )
diff --git a/lib/raid6/algos.c b/lib/raid6/algos.c
index 975c6e0434bd..e1923b602bbc 100644
--- a/lib/raid6/algos.c
+++ b/lib/raid6/algos.c
@@ -69,6 +69,9 @@ const struct raid6_calls * const raid6_algos[] = {
#if defined(CONFIG_TILEGX)
&raid6_tilegx8,
#endif
+#if defined(CONFIG_S390)
+ &raid6_s390vx8,
+#endif
&raid6_intx1,
&raid6_intx2,
&raid6_intx4,
diff --git a/lib/raid6/s390vx.uc b/lib/raid6/s390vx.uc
new file mode 100644
index 000000000000..7b45191a655f
--- /dev/null
+++ b/lib/raid6/s390vx.uc
@@ -0,0 +1,168 @@
+/*
+ * raid6_vx$#.c
+ *
+ * $#-way unrolled RAID6 gen/xor functions for s390
+ * based on the vector facility
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ *
+ * This file is postprocessed using unroll.awk.
+ */
+
+#include <linux/raid/pq.h>
+#include <asm/fpu/api.h>
+
+asm(".include \"asm/vx-insn.h\"\n");
+
+#define NSIZE 16
+
+static inline void LOAD_CONST(void)
+{
+ asm volatile("VREPIB %v24,7");
+ asm volatile("VREPIB %v25,0x1d");
+}
+
+/*
+ * The SHLBYTE() operation shifts each of the 16 bytes in
+ * vector register y left by 1 bit and stores the result in
+ * vector register x.
+ */
+static inline void SHLBYTE(int x, int y)
+{
+ asm volatile ("VAB %0,%1,%1" : : "i" (x), "i" (y));
+}
+
+/*
+ * For each of the 16 bytes in the vector register y the MASK()
+ * operation returns 0xFF if the high bit of the byte is 1,
+ * or 0x00 if the high bit is 0. The result is stored in vector
+ * register x.
+ */
+static inline void MASK(int x, int y)
+{
+ asm volatile ("VESRAVB %0,%1,24" : : "i" (x), "i" (y));
+}
+
+static inline void AND(int x, int y, int z)
+{
+ asm volatile ("VN %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
+}
+
+static inline void XOR(int x, int y, int z)
+{
+ asm volatile ("VX %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
+}
+
+static inline void LOAD_DATA(int x, int n, u8 *ptr)
+{
+ typedef struct { u8 _[16*n]; } addrtype;
+ register addrtype *__ptr asm("1") = (addrtype *) ptr;
+
+ asm volatile ("VLM %2,%3,0,%r1"
+ : : "m" (*__ptr), "a" (__ptr), "i" (x), "i" (x + n - 1));
+}
+
+static inline void STORE_DATA(int x, int n, u8 *ptr)
+{
+ typedef struct { u8 _[16*n]; } addrtype;
+ register addrtype *__ptr asm("1") = (addrtype *) ptr;
+
+ asm volatile ("VSTM %2,%3,0,1"
+ : "=m" (*__ptr) : "a" (__ptr), "i" (x), "i" (x + n - 1));
+}
+
+static inline void COPY_VEC(int x, int y)
+{
+ asm volatile ("VLR %0,%1" : : "i" (x), "i" (y));
+}
+
+static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+ struct kernel_fpu vxstate;
+ u8 **dptr, *p, *q;
+ int d, z, z0;
+
+ kernel_fpu_begin(&vxstate, KERNEL_VXR);
+ LOAD_CONST();
+
+ dptr = (u8 **) ptrs;
+ z0 = disks - 3; /* Highest data disk */
+ p = dptr[z0 + 1]; /* XOR parity */
+ q = dptr[z0 + 2]; /* RS syndrome */
+
+ for (d = 0; d < bytes; d += $#*NSIZE) {
+ LOAD_DATA(0,$#,&dptr[z0][d]);
+ COPY_VEC(8+$$,0+$$);
+ for (z = z0 - 1; z >= 0; z--) {
+ MASK(16+$$,8+$$);
+ AND(16+$$,16+$$,25);
+ SHLBYTE(8+$$,8+$$);
+ XOR(8+$$,8+$$,16+$$);
+ LOAD_DATA(16,$#,&dptr[z][d]);
+ XOR(0+$$,0+$$,16+$$);
+ XOR(8+$$,8+$$,16+$$);
+ }
+ STORE_DATA(0,$#,&p[d]);
+ STORE_DATA(8,$#,&q[d]);
+ }
+ kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop,
+ size_t bytes, void **ptrs)
+{
+ struct kernel_fpu vxstate;
+ u8 **dptr, *p, *q;
+ int d, z, z0;
+
+ dptr = (u8 **) ptrs;
+ z0 = stop; /* P/Q right side optimization */
+ p = dptr[disks - 2]; /* XOR parity */
+ q = dptr[disks - 1]; /* RS syndrome */
+
+ kernel_fpu_begin(&vxstate, KERNEL_VXR);
+ LOAD_CONST();
+
+ for (d = 0; d < bytes; d += $#*NSIZE) {
+ /* P/Q data pages */
+ LOAD_DATA(0,$#,&dptr[z0][d]);
+ COPY_VEC(8+$$,0+$$);
+ for (z = z0 - 1; z >= start; z--) {
+ MASK(16+$$,8+$$);
+ AND(16+$$,16+$$,25);
+ SHLBYTE(8+$$,8+$$);
+ XOR(8+$$,8+$$,16+$$);
+ LOAD_DATA(16,$#,&dptr[z][d]);
+ XOR(0+$$,0+$$,16+$$);
+ XOR(8+$$,8+$$,16+$$);
+ }
+ /* P/Q left side optimization */
+ for (z = start - 1; z >= 0; z--) {
+ MASK(16+$$,8+$$);
+ AND(16+$$,16+$$,25);
+ SHLBYTE(8+$$,8+$$);
+ XOR(8+$$,8+$$,16+$$);
+ }
+ LOAD_DATA(16,$#,&p[d]);
+ XOR(16+$$,16+$$,0+$$);
+ STORE_DATA(16,$#,&p[d]);
+ LOAD_DATA(16,$#,&q[d]);
+ XOR(16+$$,16+$$,8+$$);
+ STORE_DATA(16,$#,&q[d]);
+ }
+ kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+static int raid6_s390vx$#_valid(void)
+{
+ return MACHINE_HAS_VX;
+}
+
+const struct raid6_calls raid6_s390vx$# = {
+ raid6_s390vx$#_gen_syndrome,
+ raid6_s390vx$#_xor_syndrome,
+ raid6_s390vx$#_valid,
+ "vx128x$#",
+ 1
+};