From: Pan Xinhui <xinhui@linux.vnet.ibm.com>
To: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
Michael Ellerman <mpe@ellerman.id.au>,
Boqun Feng <boqun.feng@gmail.com>,
"'Peter Zijlstra (Intel)\"" <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH] powerpc: introduce {cmp}xchg for u8 and u16
Date: Fri, 08 Apr 2016 14:41:46 +0800 [thread overview]
Message-ID: <570752AA.9050603@linux.vnet.ibm.com> (raw)
From: pan xinhui <xinhui.pan@linux.vnet.ibm.com>
Implement xchg{u8,u16}{local,relaxed}, and
cmpxchg{u8,u16}{,local,acquire,relaxed}.
Atomic operation on 8-bit and 16-bit data type is supported from power7
Signed-off-by: pan xinhui <xinhui.pan@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/cmpxchg.h | 265 +++++++++++++++++++++++++++++++++++++
1 file changed, 265 insertions(+)
diff --git a/arch/powerpc/include/asm/cmpxchg.h b/arch/powerpc/include/asm/cmpxchg.h
index 44efe73..928ad89 100644
--- a/arch/powerpc/include/asm/cmpxchg.h
+++ b/arch/powerpc/include/asm/cmpxchg.h
@@ -15,6 +15,74 @@
*/
static __always_inline unsigned long
+__xchg_u8_local(volatile void *p, unsigned long val)
+{
+ unsigned long prev;
+
+ __asm__ __volatile__(
+"1: lbarx %0,0,%2\n"
+ PPC405_ERR77(0,%2)
+" stbcx. %3,0,%2\n"
+" bne- 1b"
+ : "=&r" (prev), "+m" (*(volatile unsigned char *)p)
+ : "r" (p), "r" (val)
+ : "cc", "memory");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__xchg_u8_relaxed(u8 *p, unsigned long val)
+{
+ unsigned long prev;
+
+ __asm__ __volatile__(
+"1: lbarx %0,0,%2\n"
+ PPC405_ERR77(0,%2)
+" stbcx. %3,0,%2\n"
+" bne- 1b"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (val)
+ : "cc");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__xchg_u16_local(volatile void *p, unsigned long val)
+{
+ unsigned long prev;
+
+ __asm__ __volatile__(
+"1: lharx %0,0,%2\n"
+ PPC405_ERR77(0,%2)
+" sthcx. %3,0,%2\n"
+" bne- 1b"
+ : "=&r" (prev), "+m" (*(volatile unsigned short *)p)
+ : "r" (p), "r" (val)
+ : "cc", "memory");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__xchg_u16_relaxed(u16 *p, unsigned long val)
+{
+ unsigned long prev;
+
+ __asm__ __volatile__(
+"1: lharx %0,0,%2\n"
+ PPC405_ERR77(0,%2)
+" sthcx. %3,0,%2\n"
+" bne- 1b"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (val)
+ : "cc");
+
+ return prev;
+}
+
+static __always_inline unsigned long
__xchg_u32_local(volatile void *p, unsigned long val)
{
unsigned long prev;
@@ -88,6 +156,10 @@ static __always_inline unsigned long
__xchg_local(volatile void *ptr, unsigned long x, unsigned int size)
{
switch (size) {
+ case 1:
+ return __xchg_u8_local(ptr, x);
+ case 2:
+ return __xchg_u16_local(ptr, x);
case 4:
return __xchg_u32_local(ptr, x);
#ifdef CONFIG_PPC64
@@ -103,6 +175,10 @@ static __always_inline unsigned long
__xchg_relaxed(void *ptr, unsigned long x, unsigned int size)
{
switch (size) {
+ case 1:
+ return __xchg_u8_relaxed(ptr, x);
+ case 2:
+ return __xchg_u16_relaxed(ptr, x);
case 4:
return __xchg_u32_relaxed(ptr, x);
#ifdef CONFIG_PPC64
@@ -132,6 +208,179 @@ __xchg_relaxed(void *ptr, unsigned long x, unsigned int size)
*/
static __always_inline unsigned long
+__cmpxchg_u8(volatile unsigned char *p, unsigned long old, unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+ PPC_ATOMIC_ENTRY_BARRIER
+"1: lbarx %0,0,%2 # __cmpxchg_u8\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" stbcx. %4,0,%2\n"
+" bne- 1b\n"
+ PPC_ATOMIC_EXIT_BARRIER
+ "\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc", "memory");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_u8_local(volatile unsigned char *p, unsigned long old,
+ unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+"1: lbarx %0,0,%2 # __cmpxchg_u8_local\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" stbcx. %4,0,%2\n"
+" bne- 1b\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc", "memory");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_u8_relaxed(u8 *p, unsigned long old, unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+"1: lbarx %0,0,%2 # __cmpxchg_u8_relaxed\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" stbcx. %4,0,%2\n"
+" bne- 1b\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_u8_acquire(u8 *p, unsigned long old, unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+"1: lbarx %0,0,%2 # __cmpxchg_u8_acquire\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" stbcx. %4,0,%2\n"
+" bne- 1b\n"
+ PPC_ACQUIRE_BARRIER
+ "\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc", "memory");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_u16(volatile unsigned short *p, unsigned long old, unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+ PPC_ATOMIC_ENTRY_BARRIER
+"1: lharx %0,0,%2 # __cmpxchg_u16\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" sthcx. %4,0,%2\n"
+" bne- 1b\n"
+ PPC_ATOMIC_EXIT_BARRIER
+ "\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc", "memory");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_u16_local(volatile unsigned short *p, unsigned long old,
+ unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+"1: lharx %0,0,%2 # __cmpxchg_u16_local\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" sthcx. %4,0,%2\n"
+" bne- 1b\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc", "memory");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_u16_relaxed(u16 *p, unsigned long old, unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+"1: lharx %0,0,%2 # __cmpxchg_u16_relaxed\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" sthcx. %4,0,%2\n"
+" bne- 1b\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc");
+
+ return prev;
+}
+
+static __always_inline unsigned long
+__cmpxchg_u16_acquire(u16 *p, unsigned long old, unsigned long new)
+{
+ unsigned long prev = 0;
+
+ __asm__ __volatile__ (
+"1: lharx %0,0,%2 # __cmpxchg_u16_acquire\n"
+" cmpw 0,%0,%3\n"
+" bne- 2f\n"
+ PPC405_ERR77(0,%2)
+" sthcx. %4,0,%2\n"
+" bne- 1b\n"
+ PPC_ACQUIRE_BARRIER
+ "\n"
+"2:"
+ : "=&r" (prev), "+m" (*p)
+ : "r" (p), "r" (old), "r" (new)
+ : "cc", "memory");
+
+ return prev;
+}
+
+
+static __always_inline unsigned long
__cmpxchg_u32(volatile unsigned int *p, unsigned long old, unsigned long new)
{
unsigned int prev;
@@ -316,6 +565,10 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new,
unsigned int size)
{
switch (size) {
+ case 1:
+ return __cmpxchg_u8(ptr, old, new);
+ case 2:
+ return __cmpxchg_u16(ptr, old, new);
case 4:
return __cmpxchg_u32(ptr, old, new);
#ifdef CONFIG_PPC64
@@ -332,6 +585,10 @@ __cmpxchg_local(volatile void *ptr, unsigned long old, unsigned long new,
unsigned int size)
{
switch (size) {
+ case 1:
+ return __cmpxchg_u8_local(ptr, old, new);
+ case 2:
+ return __cmpxchg_u16_local(ptr, old, new);
case 4:
return __cmpxchg_u32_local(ptr, old, new);
#ifdef CONFIG_PPC64
@@ -348,6 +605,10 @@ __cmpxchg_relaxed(void *ptr, unsigned long old, unsigned long new,
unsigned int size)
{
switch (size) {
+ case 1:
+ return __cmpxchg_u8_relaxed(ptr, old, new);
+ case 2:
+ return __cmpxchg_u16_relaxed(ptr, old, new);
case 4:
return __cmpxchg_u32_relaxed(ptr, old, new);
#ifdef CONFIG_PPC64
@@ -364,6 +625,10 @@ __cmpxchg_acquire(void *ptr, unsigned long old, unsigned long new,
unsigned int size)
{
switch (size) {
+ case 1:
+ return __cmpxchg_u8_acquire(ptr, old, new);
+ case 2:
+ return __cmpxchg_u16_acquire(ptr, old, new);
case 4:
return __cmpxchg_u32_acquire(ptr, old, new);
#ifdef CONFIG_PPC64
--
1.9.1
next reply other threads:[~2016-04-08 6:42 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-08 6:41 Pan Xinhui [this message]
2016-04-08 7:47 ` [PATCH] powerpc: introduce {cmp}xchg for u8 and u16 Peter Zijlstra
2016-04-10 14:17 ` Pan Xinhui
2016-04-12 14:30 ` Peter Zijlstra
2016-04-13 11:15 ` Pan Xinhui
2016-04-13 15:53 ` Waiman Long
2016-04-14 8:31 ` Pan Xinhui
2016-04-16 19:43 ` Arnd Bergmann
2016-04-16 19:43 ` Arnd Bergmann
2016-04-18 10:19 ` Pan Xinhui
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