From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751733AbeBWI2f (ORCPT ); Fri, 23 Feb 2018 03:28:35 -0500 Received: from terminus.zytor.com ([198.137.202.136]:56683 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750796AbeBWI2d (ORCPT ); Fri, 23 Feb 2018 03:28:33 -0500 Date: Fri, 23 Feb 2018 00:27:54 -0800 From: tip-bot for Andrea Parri Message-ID: Cc: will.deacon@arm.com, rth@twiddle.net, mattst88@gmail.com, tglx@linutronix.de, hpa@zytor.com, parri.andrea@gmail.com, ink@jurassic.park.msu.ru, stern@rowland.harvard.edu, paulmck@linux.vnet.ibm.com, mingo@kernel.org, linux-kernel@vger.kernel.org, peterz@infradead.org, torvalds@linux-foundation.org, akpm@linux-foundation.org Reply-To: mattst88@gmail.com, rth@twiddle.net, will.deacon@arm.com, tglx@linutronix.de, hpa@zytor.com, stern@rowland.harvard.edu, parri.andrea@gmail.com, ink@jurassic.park.msu.ru, akpm@linux-foundation.org, paulmck@linux.vnet.ibm.com, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, peterz@infradead.org, mingo@kernel.org In-Reply-To: <1519291469-5702-1-git-send-email-parri.andrea@gmail.com> References: <1519291469-5702-1-git-send-email-parri.andrea@gmail.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:locking/urgent] locking/xchg/alpha: Clean up barrier usage by using smp_mb() in place of __ASM__MB Git-Commit-ID: 79d442461df7478cdd0c50d9b8a76f431f150fa3 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 79d442461df7478cdd0c50d9b8a76f431f150fa3 Gitweb: https://git.kernel.org/tip/79d442461df7478cdd0c50d9b8a76f431f150fa3 Author: Andrea Parri AuthorDate: Thu, 22 Feb 2018 10:24:29 +0100 Committer: Ingo Molnar CommitDate: Fri, 23 Feb 2018 08:38:15 +0100 locking/xchg/alpha: Clean up barrier usage by using smp_mb() in place of __ASM__MB Replace each occurrence of __ASM__MB with a (trailing) smp_mb() in xchg(), cmpxchg(), and remove the now unused __ASM__MB definitions; this improves readability, with no additional synchronization cost. Suggested-by: Will Deacon Signed-off-by: Andrea Parri Acked-by: Paul E. McKenney Cc: Alan Stern Cc: Andrew Morton Cc: Ivan Kokshaysky Cc: Linus Torvalds Cc: Matt Turner Cc: Peter Zijlstra Cc: Richard Henderson Cc: Thomas Gleixner Cc: linux-alpha@vger.kernel.org Link: http://lkml.kernel.org/r/1519291469-5702-1-git-send-email-parri.andrea@gmail.com Signed-off-by: Ingo Molnar --- arch/alpha/include/asm/cmpxchg.h | 6 ------ arch/alpha/include/asm/xchg.h | 16 ++++++++-------- 2 files changed, 8 insertions(+), 14 deletions(-) diff --git a/arch/alpha/include/asm/cmpxchg.h b/arch/alpha/include/asm/cmpxchg.h index 46ebf14aed4e..8a2b331e43fe 100644 --- a/arch/alpha/include/asm/cmpxchg.h +++ b/arch/alpha/include/asm/cmpxchg.h @@ -6,7 +6,6 @@ * Atomic exchange routines. */ -#define __ASM__MB #define ____xchg(type, args...) __xchg ## type ## _local(args) #define ____cmpxchg(type, args...) __cmpxchg ## type ## _local(args) #include @@ -33,10 +32,6 @@ cmpxchg_local((ptr), (o), (n)); \ }) -#ifdef CONFIG_SMP -#undef __ASM__MB -#define __ASM__MB "\tmb\n" -#endif #undef ____xchg #undef ____cmpxchg #define ____xchg(type, args...) __xchg ##type(args) @@ -64,7 +59,6 @@ cmpxchg((ptr), (o), (n)); \ }) -#undef __ASM__MB #undef ____cmpxchg #endif /* _ALPHA_CMPXCHG_H */ diff --git a/arch/alpha/include/asm/xchg.h b/arch/alpha/include/asm/xchg.h index e2660866ce97..e1facf6fc244 100644 --- a/arch/alpha/include/asm/xchg.h +++ b/arch/alpha/include/asm/xchg.h @@ -28,12 +28,12 @@ ____xchg(_u8, volatile char *m, unsigned long val) " or %1,%2,%2\n" " stq_c %2,0(%3)\n" " beq %2,2f\n" - __ASM__MB ".subsection 2\n" "2: br 1b\n" ".previous" : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64) : "r" ((long)m), "1" (val) : "memory"); + smp_mb(); return ret; } @@ -52,12 +52,12 @@ ____xchg(_u16, volatile short *m, unsigned long val) " or %1,%2,%2\n" " stq_c %2,0(%3)\n" " beq %2,2f\n" - __ASM__MB ".subsection 2\n" "2: br 1b\n" ".previous" : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64) : "r" ((long)m), "1" (val) : "memory"); + smp_mb(); return ret; } @@ -72,12 +72,12 @@ ____xchg(_u32, volatile int *m, unsigned long val) " bis $31,%3,%1\n" " stl_c %1,%2\n" " beq %1,2f\n" - __ASM__MB ".subsection 2\n" "2: br 1b\n" ".previous" : "=&r" (val), "=&r" (dummy), "=m" (*m) : "rI" (val), "m" (*m) : "memory"); + smp_mb(); return val; } @@ -92,12 +92,12 @@ ____xchg(_u64, volatile long *m, unsigned long val) " bis $31,%3,%1\n" " stq_c %1,%2\n" " beq %1,2f\n" - __ASM__MB ".subsection 2\n" "2: br 1b\n" ".previous" : "=&r" (val), "=&r" (dummy), "=m" (*m) : "rI" (val), "m" (*m) : "memory"); + smp_mb(); return val; } @@ -150,12 +150,12 @@ ____cmpxchg(_u8, volatile char *m, unsigned char old, unsigned char new) " stq_c %2,0(%4)\n" " beq %2,3f\n" "2:\n" - __ASM__MB ".subsection 2\n" "3: br 1b\n" ".previous" : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64) : "r" ((long)m), "Ir" (old), "1" (new) : "memory"); + smp_mb(); return prev; } @@ -177,12 +177,12 @@ ____cmpxchg(_u16, volatile short *m, unsigned short old, unsigned short new) " stq_c %2,0(%4)\n" " beq %2,3f\n" "2:\n" - __ASM__MB ".subsection 2\n" "3: br 1b\n" ".previous" : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64) : "r" ((long)m), "Ir" (old), "1" (new) : "memory"); + smp_mb(); return prev; } @@ -200,12 +200,12 @@ ____cmpxchg(_u32, volatile int *m, int old, int new) " stl_c %1,%2\n" " beq %1,3f\n" "2:\n" - __ASM__MB ".subsection 2\n" "3: br 1b\n" ".previous" : "=&r"(prev), "=&r"(cmp), "=m"(*m) : "r"((long) old), "r"(new), "m"(*m) : "memory"); + smp_mb(); return prev; } @@ -223,12 +223,12 @@ ____cmpxchg(_u64, volatile long *m, unsigned long old, unsigned long new) " stq_c %1,%2\n" " beq %1,3f\n" "2:\n" - __ASM__MB ".subsection 2\n" "3: br 1b\n" ".previous" : "=&r"(prev), "=&r"(cmp), "=m"(*m) : "r"((long) old), "r"(new), "m"(*m) : "memory"); + smp_mb(); return prev; }