From: Gunnar Larisch Date: Thu, 7 Feb 2008 08:16:22 +0000 (-0800) Subject: Add cmpxchg_local to ppc X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=85fdbe1b4b33b797321bfadf706b355e7cca6165;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git Add cmpxchg_local to ppc Add a local processor version of cmpxchg for ppc. Implements __cmpxchg_u32_local and uses it for 32 bits cmpxchg_local. It uses the non NMI safe cmpxchg_local_generic for 1, 2 and 8 bytes cmpxchg_local. Signed-off-by: Gunnar Larisch Signed-off-by: Mathieu Desnoyers Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Kumar Gala Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/asm-ppc/system.h b/include/asm-ppc/system.h index 51df94c73846..0593cb889d45 100644 --- a/include/asm-ppc/system.h +++ b/include/asm-ppc/system.h @@ -209,12 +209,34 @@ __cmpxchg_u32(volatile unsigned int *p, unsigned int old, unsigned int new) return prev; } +static inline unsigned long +__cmpxchg_u32_local(volatile unsigned int *p, unsigned int old, + unsigned int new) +{ + unsigned int prev; + + __asm__ __volatile__ ("\n\ +1: lwarx %0,0,%2 \n\ + cmpw 0,%0,%3 \n\ + bne 2f \n" + PPC405_ERR77(0,%2) +" stwcx. %4,0,%2 \n\ + bne- 1b\n" +"2:" + : "=&r" (prev), "=m" (*p) + : "r" (p), "r" (old), "r" (new), "m" (*p) + : "cc", "memory"); + + return prev; +} + /* This function doesn't exist, so you'll get a linker error if something tries to do an invalid cmpxchg(). */ extern void __cmpxchg_called_with_bad_pointer(void); static __inline__ unsigned long -__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) +__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, + unsigned int size) { switch (size) { case 4: @@ -228,7 +250,7 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) return old; } -#define cmpxchg(ptr,o,n) \ +#define cmpxchg(ptr, o, n) \ ({ \ __typeof__(*(ptr)) _o_ = (o); \ __typeof__(*(ptr)) _n_ = (n); \ @@ -236,6 +258,31 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) (unsigned long)_n_, sizeof(*(ptr))); \ }) +#include + +static inline unsigned long __cmpxchg_local(volatile void *ptr, + unsigned long old, + unsigned long new, int size) +{ + switch (size) { + case 4: + return __cmpxchg_u32_local(ptr, old, new); + default: + return __cmpxchg_local_generic(ptr, old, new, size); + } + + return old; +} + +/* + * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make + * them available. + */ +#define cmpxchg_local(ptr, o, n) \ + ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \ + (unsigned long)(n), sizeof(*(ptr)))) +#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) + #define arch_align_stack(x) (x) #endif /* __KERNEL__ */