From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932568AbbA1AYZ (ORCPT ); Tue, 27 Jan 2015 19:24:25 -0500 Received: from mail-we0-f169.google.com ([74.125.82.169]:61571 "EHLO mail-we0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759393AbbA1AYW (ORCPT ); Tue, 27 Jan 2015 19:24:22 -0500 From: Frederic Weisbecker To: Ingo Molnar , Peter Zijlstra Cc: LKML , Frederic Weisbecker , Steven Rostedt , Linus Torvalds Subject: [RFC PATCH 2/4] sched: Use traced preempt count operations to toggle PREEMPT_ACTIVE Date: Wed, 28 Jan 2015 01:24:10 +0100 Message-Id: <1422404652-29067-3-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1422404652-29067-1-git-send-email-fweisbec@gmail.com> References: <1422404652-29067-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org d1f74e20b5b064a130cd0743a256c2d3cfe84010 turned PREEMPT_ACTIVE modifiers to use raw untraced preempt count operations. Meanwhile this prevents from debugging and tracing preemption disabled if we pull that responsibility to schedule() callers (see following patches). Is there anything we can do about that? Cc: Linus Torvalds Cc: Steven Rostedt Cc: Ingo Molnar Cc: Peter Zijlstra Signed-off-by: Frederic Weisbecker --- kernel/sched/core.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index bbef95d..89b165f 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2883,9 +2883,9 @@ void __sched schedule_preempt_disabled(void) static void preempt_schedule_common(void) { do { - __preempt_count_add(PREEMPT_ACTIVE); + preempt_count_add(PREEMPT_ACTIVE); __schedule(); - __preempt_count_sub(PREEMPT_ACTIVE); + preempt_count_sub(PREEMPT_ACTIVE); /* * Check again in case we missed a preemption opportunity @@ -2938,7 +2938,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_context(void) return; do { - __preempt_count_add(PREEMPT_ACTIVE); + preempt_count_add(PREEMPT_ACTIVE); /* * Needs preempt disabled in case user_exit() is traced * and the tracer calls preempt_enable_notrace() causing @@ -2948,7 +2948,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_context(void) __schedule(); exception_exit(prev_ctx); - __preempt_count_sub(PREEMPT_ACTIVE); + preempt_count_sub(PREEMPT_ACTIVE); barrier(); } while (need_resched()); } @@ -2973,11 +2973,11 @@ asmlinkage __visible void __sched preempt_schedule_irq(void) prev_state = exception_enter(); do { - __preempt_count_add(PREEMPT_ACTIVE); + preempt_count_add(PREEMPT_ACTIVE); local_irq_enable(); __schedule(); local_irq_disable(); - __preempt_count_sub(PREEMPT_ACTIVE); + preempt_count_sub(PREEMPT_ACTIVE); /* * Check again in case we missed a preemption opportunity -- 2.1.4