From b791d1193af9772040e592d5aa161790f800b762 Mon Sep 17 00:00:00 2001 From: David Daney Date: Mon, 13 Jul 2009 11:15:19 -0700 Subject: MIPS: Allow kernel use of LL/SC to be separate from the presence of LL/SC. On some CPUs, it is more efficient to disable and enable interrupts in the kernel rather than use ll/sc for atomic operations. But if we were to set cpu_has_llsc to false, we would break the userspace futex interface (in asm/futex.h). We separate the two concepts, with a new predicate kernel_uses_llsc, that lets us disable the kernel's use of ll/sc while still allowing the futex code to use it. Also there were a couple of cases in bitops.h where we were using ll/sc unconditionally even if cpu_has_llsc were false. Signed-off-by: David Daney Signed-off-by: Ralf Baechle --- arch/mips/include/asm/system.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/mips/include/asm/system.h') diff --git a/arch/mips/include/asm/system.h b/arch/mips/include/asm/system.h index cc7262ff0765..fcf5f98d90cc 100644 --- a/arch/mips/include/asm/system.h +++ b/arch/mips/include/asm/system.h @@ -94,7 +94,7 @@ static inline unsigned long __xchg_u32(volatile int * m, unsigned int val) { __u32 retval; - if (cpu_has_llsc && R10000_LLSC_WAR) { + if (kernel_uses_llsc && R10000_LLSC_WAR) { unsigned long dummy; __asm__ __volatile__( @@ -109,7 +109,7 @@ static inline unsigned long __xchg_u32(volatile int * m, unsigned int val) : "=&r" (retval), "=m" (*m), "=&r" (dummy) : "R" (*m), "Jr" (val) : "memory"); - } else if (cpu_has_llsc) { + } else if (kernel_uses_llsc) { unsigned long dummy; __asm__ __volatile__( @@ -146,7 +146,7 @@ static inline __u64 __xchg_u64(volatile __u64 * m, __u64 val) { __u64 retval; - if (cpu_has_llsc && R10000_LLSC_WAR) { + if (kernel_uses_llsc && R10000_LLSC_WAR) { unsigned long dummy; __asm__ __volatile__( @@ -159,7 +159,7 @@ static inline __u64 __xchg_u64(volatile __u64 * m, __u64 val) : "=&r" (retval), "=m" (*m), "=&r" (dummy) : "R" (*m), "Jr" (val) : "memory"); - } else if (cpu_has_llsc) { + } else if (kernel_uses_llsc) { unsigned long dummy; __asm__ __volatile__( -- cgit v1.2.3