Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752729AbcCXOjG (ORCPT ); Thu, 24 Mar 2016 10:39:06 -0400 Received: from mail-wm0-f44.google.com ([74.125.82.44]:36878 "EHLO mail-wm0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752570AbcCXOiw (ORCPT ); Thu, 24 Mar 2016 10:38:52 -0400 From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Peter Zijlstra , Linus Torvalds , Thomas Gleixner , Ingo Molnar , Andrew Morton Subject: [PATCH 3/3] Revert "atomic: Export fetch_or()" Date: Thu, 24 Mar 2016 15:38:01 +0100 Message-Id: <1458830281-4255-4-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1458830281-4255-1-git-send-email-fweisbec@gmail.com> References: <1458830281-4255-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2594 Lines: 88 This reverts commit 5fd7a09cfb8c6852f596c1f8c891c6158395250e. Now that we have introduced atomic_fetch_or(), fetch_or() is only used by the scheduler in order to deal with thread_info flags which type can vary across architectures. Lets confine fetch_or() back to the scheduler so that we encourage future users to use the more robust and well typed atomic_t version instead. While at it, fetch_or() gets robustified, pasting improvements from a previous patch by Ingo Molnar that avoids needless expression re-evaluations in the loop. Cc: Andrew Morton Cc: Ingo Molnar Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Frederic Weisbecker --- include/linux/atomic.h | 21 --------------------- kernel/sched/core.c | 18 ++++++++++++++++++ 2 files changed, 18 insertions(+), 21 deletions(-) diff --git a/include/linux/atomic.h b/include/linux/atomic.h index 3d64c08..506c353 100644 --- a/include/linux/atomic.h +++ b/include/linux/atomic.h @@ -579,27 +579,6 @@ static inline int atomic_fetch_or(atomic_t *p, int mask) } #endif -/** - * fetch_or - perform *ptr |= mask and return old value of *ptr - * @ptr: pointer to value - * @mask: mask to OR on the value - * - * cmpxchg based fetch_or, macro so it works for different integer types - */ -#ifndef fetch_or -#define fetch_or(ptr, mask) \ -({ typeof(*(ptr)) __old, __val = *(ptr); \ - for (;;) { \ - __old = cmpxchg((ptr), __val, __val | (mask)); \ - if (__old == __val) \ - break; \ - __val = __old; \ - } \ - __old; \ -}) -#endif - - #ifdef CONFIG_GENERIC_ATOMIC64 #include #endif diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 44db0ff..4cce134 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -321,6 +321,24 @@ static inline void init_hrtick(void) } #endif /* CONFIG_SCHED_HRTICK */ +/* + * cmpxchg based fetch_or, macro so it works for different integer types + */ +#define fetch_or(ptr, mask) \ + ({ \ + typeof(ptr) _ptr = (ptr); \ + typeof(mask) _mask = (mask); \ + typeof(*_ptr) _old, _val = *_ptr; \ + \ + for (;;) { \ + _old = cmpxchg(_ptr, _val, _val | _mask); \ + if (_old == _val) \ + break; \ + _val = _old; \ + } \ + _old; \ +}) + #if defined(CONFIG_SMP) && defined(TIF_POLLING_NRFLAG) /* * Atomically set TIF_NEED_RESCHED and test for TIF_POLLING_NRFLAG, -- 2.7.0