From 0004a9dfeaa709a7f853487aba19932c9b1a87c8 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Tue, 31 Oct 2006 03:45:07 +0000 Subject: [MIPS] Cleanup memory barriers for weakly ordered systems. Also the R4000 / R4600 LL/SC instructions imply a sync so no explicit sync needed. Signed-off-by: Ralf Baechle --- include/asm-mips/futex.h | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) (limited to 'include/asm-mips/futex.h') diff --git a/include/asm-mips/futex.h b/include/asm-mips/futex.h index ed023eae067..927a216bd53 100644 --- a/include/asm-mips/futex.h +++ b/include/asm-mips/futex.h @@ -1,19 +1,21 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (c) 2006 Ralf Baechle (ralf@linux-mips.org) + */ #ifndef _ASM_FUTEX_H #define _ASM_FUTEX_H #ifdef __KERNEL__ #include +#include #include #include #include -#ifdef CONFIG_SMP -#define __FUTEX_SMP_SYNC " sync \n" -#else -#define __FUTEX_SMP_SYNC -#endif - #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ { \ if (cpu_has_llsc && R10000_LLSC_WAR) { \ @@ -27,7 +29,7 @@ " .set mips3 \n" \ "2: sc $1, %2 \n" \ " beqzl $1, 1b \n" \ - __FUTEX_SMP_SYNC \ + __WEAK_ORDERING_MB \ "3: \n" \ " .set pop \n" \ " .set mips0 \n" \ @@ -53,7 +55,7 @@ " .set mips3 \n" \ "2: sc $1, %2 \n" \ " beqz $1, 1b \n" \ - __FUTEX_SMP_SYNC \ + __WEAK_ORDERING_MB \ "3: \n" \ " .set pop \n" \ " .set mips0 \n" \ @@ -150,7 +152,7 @@ futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval) " .set mips3 \n" "2: sc $1, %1 \n" " beqzl $1, 1b \n" - __FUTEX_SMP_SYNC + __WEAK_ORDERING_MB "3: \n" " .set pop \n" " .section .fixup,\"ax\" \n" @@ -177,7 +179,7 @@ futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval) " .set mips3 \n" "2: sc $1, %1 \n" " beqz $1, 1b \n" - __FUTEX_SMP_SYNC + __WEAK_ORDERING_MB "3: \n" " .set pop \n" " .section .fixup,\"ax\" \n" -- cgit v1.2.3-18-g5258 From a866374aecc90c7d90619727ccd851ac096b2fc7 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 6 Dec 2006 20:32:20 -0800 Subject: [PATCH] mm: pagefault_{disable,enable}() Introduce pagefault_{disable,enable}() and use these where previously we did manual preempt increments/decrements to make the pagefault handler do the atomic thing. Currently they still rely on the increased preempt count, but do not rely on the disabled preemption, this might go away in the future. (NOTE: the extra barrier() in pagefault_disable might fix some holes on machines which have too many registers for their own good) [heiko.carstens@de.ibm.com: s390 fix] Signed-off-by: Peter Zijlstra Acked-by: Nick Piggin Cc: Martin Schwidefsky Signed-off-by: Heiko Carstens Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-mips/futex.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/asm-mips/futex.h') diff --git a/include/asm-mips/futex.h b/include/asm-mips/futex.h index 927a216bd53..47e5679c235 100644 --- a/include/asm-mips/futex.h +++ b/include/asm-mips/futex.h @@ -88,7 +88,7 @@ futex_atomic_op_inuser (int encoded_op, int __user *uaddr) if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int))) return -EFAULT; - inc_preempt_count(); + pagefault_disable(); switch (op) { case FUTEX_OP_SET: @@ -115,7 +115,7 @@ futex_atomic_op_inuser (int encoded_op, int __user *uaddr) ret = -ENOSYS; } - dec_preempt_count(); + pagefault_enable(); if (!ret) { switch (cmp) { -- cgit v1.2.3-18-g5258