From 5927145efd5de71976e62e2822511b13014d7e56 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 19 Mar 2018 11:38:13 +0100 Subject: x86/cpu: Remove the CONFIG_X86_PPRO_FENCE=y quirk There were only a few Pentium Pro multiprocessors systems where this errata applied. They are more than 20 years old now, and we've slowly dropped places which put the workarounds in and discouraged anyone from enabling the workaround. Get rid of it for good. Tested-by: Tom Lendacky Signed-off-by: Christoph Hellwig Reviewed-by: Thomas Gleixner Reviewed-by: Konrad Rzeszutek Wilk Cc: David Woodhouse Cc: Joerg Roedel Cc: Jon Mason Cc: Linus Torvalds Cc: Muli Ben-Yehuda Cc: Peter Zijlstra Cc: iommu@lists.linux-foundation.org Link: http://lkml.kernel.org/r/20180319103826.12853-2-hch@lst.de Signed-off-by: Ingo Molnar --- arch/x86/include/asm/barrier.h | 30 ------------------------------ 1 file changed, 30 deletions(-) (limited to 'arch/x86/include/asm/barrier.h') diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h index e1259f0..042b5e8 100644 --- a/arch/x86/include/asm/barrier.h +++ b/arch/x86/include/asm/barrier.h @@ -52,11 +52,7 @@ static inline unsigned long array_index_mask_nospec(unsigned long index, #define barrier_nospec() alternative_2("", "mfence", X86_FEATURE_MFENCE_RDTSC, \ "lfence", X86_FEATURE_LFENCE_RDTSC) -#ifdef CONFIG_X86_PPRO_FENCE -#define dma_rmb() rmb() -#else #define dma_rmb() barrier() -#endif #define dma_wmb() barrier() #ifdef CONFIG_X86_32 @@ -68,30 +64,6 @@ static inline unsigned long array_index_mask_nospec(unsigned long index, #define __smp_wmb() barrier() #define __smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0) -#if defined(CONFIG_X86_PPRO_FENCE) - -/* - * For this option x86 doesn't have a strong TSO memory - * model and we should fall back to full barriers. - */ - -#define __smp_store_release(p, v) \ -do { \ - compiletime_assert_atomic_type(*p); \ - __smp_mb(); \ - WRITE_ONCE(*p, v); \ -} while (0) - -#define __smp_load_acquire(p) \ -({ \ - typeof(*p) ___p1 = READ_ONCE(*p); \ - compiletime_assert_atomic_type(*p); \ - __smp_mb(); \ - ___p1; \ -}) - -#else /* regular x86 TSO memory ordering */ - #define __smp_store_release(p, v) \ do { \ compiletime_assert_atomic_type(*p); \ @@ -107,8 +79,6 @@ do { \ ___p1; \ }) -#endif - /* Atomic operations are already serializing on x86 */ #define __smp_mb__before_atomic() barrier() #define __smp_mb__after_atomic() barrier() -- cgit v1.1