From 0b77d6701cf8d4eb343a83fa8d7eca81a863bb7c Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Wed, 4 Oct 2017 19:27:05 +0200
Subject: [PATCH] s390: implement memset16, memset32 & memset64
Provide fast versions of the new memset variants. E.g. the generic
memset64 is ten times slower than the optimized version if used on a
whole page.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
arch/s390/include/asm/string.h | 22 +++++++++++++++++
arch/s390/lib/mem.S | 44 ++++++++++++++++++++++++++++++++++
2 files changed, 66 insertions(+)
diff --git a/arch/s390/include/asm/string.h b/arch/s390/include/asm/string.h
index 8fb43319693db..aa9c3a0f59ff4 100644
--- a/arch/s390/include/asm/string.h
+++ b/arch/s390/include/asm/string.h
@@ -17,6 +17,9 @@
#define __HAVE_ARCH_MEMMOVE /* gcc builtin & arch function */
#define __HAVE_ARCH_MEMSCAN /* inline & arch function */
#define __HAVE_ARCH_MEMSET /* gcc builtin & arch function */
+#define __HAVE_ARCH_MEMSET16 /* arch function */
+#define __HAVE_ARCH_MEMSET32 /* arch function */
+#define __HAVE_ARCH_MEMSET64 /* arch function */
#define __HAVE_ARCH_STRCAT /* inline & arch function */
#define __HAVE_ARCH_STRCMP /* arch function */
#define __HAVE_ARCH_STRCPY /* inline & arch function */
@@ -49,6 +52,25 @@ extern char *strstr(const char *, const char *);
#undef __HAVE_ARCH_STRSEP
#undef __HAVE_ARCH_STRSPN
+void *__memset16(uint16_t *s, uint16_t v, size_t count);
+void *__memset32(uint32_t *s, uint32_t v, size_t count);
+void *__memset64(uint64_t *s, uint64_t v, size_t count);
+
+static inline void *memset16(uint16_t *s, uint16_t v, size_t count)
+{
+ return __memset16(s, v, count * sizeof(v));
+}
+
+static inline void *memset32(uint32_t *s, uint32_t v, size_t count)
+{
+ return __memset32(s, v, count * sizeof(v));
+}
+
+static inline void *memset64(uint64_t *s, uint64_t v, size_t count)
+{
+ return __memset64(s, v, count * sizeof(v));
+}
+
#if !defined(IN_ARCH_STRING_C) && (!defined(CONFIG_FORTIFY_SOURCE) || defined(__NO_FORTIFY))
static inline void *memchr(const void * s, int c, size_t n)
diff --git a/arch/s390/lib/mem.S b/arch/s390/lib/mem.S
index 7ff79a4ff00cd..f88cf6983849b 100644
--- a/arch/s390/lib/mem.S
+++ b/arch/s390/lib/mem.S
@@ -126,3 +126,47 @@ ENTRY(memcpy)
.Lmemcpy_mvc:
mvc 0(1,%r1),0(%r3)
EXPORT_SYMBOL(memcpy)
+
+/*
+ * __memset16/32/64
+ *
+ * void *__memset16(uint16_t *s, uint16_t v, size_t count)
+ * void *__memset32(uint32_t *s, uint32_t v, size_t count)
+ * void *__memset64(uint64_t *s, uint64_t v, size_t count)
+ */
+.macro __MEMSET bits,bytes,insn
+ENTRY(__memset\bits)
+ ltgr %r4,%r4
+ bzr %r14
+ cghi %r4,\bytes
+ je .L__memset_exit\bits
+ aghi %r4,-(\bytes+1)
+ srlg %r5,%r4,8
+ ltgr %r5,%r5
+ lgr %r1,%r2
+ jz .L__memset_remainder\bits
+.L__memset_loop\bits:
+ \insn %r3,0(%r1)
+ mvc \bytes(256-\bytes,%r1),0(%r1)
+ la %r1,256(%r1)
+ brctg %r5,.L__memset_loop\bits
+.L__memset_remainder\bits:
+ \insn %r3,0(%r1)
+ larl %r5,.L__memset_mvc\bits
+ ex %r4,0(%r5)
+ br %r14
+.L__memset_exit\bits:
+ \insn %r3,0(%r2)
+ br %r14
+.L__memset_mvc\bits:
+ mvc \bytes(1,%r1),0(%r1)
+.endm
+
+__MEMSET 16,2,sth
+EXPORT_SYMBOL(__memset16)
+
+__MEMSET 32,4,st
+EXPORT_SYMBOL(__memset32)
+
+__MEMSET 64,8,stg
+EXPORT_SYMBOL(__memset64)
--
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