From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 064AFC2D0A8 for ; Mon, 28 Sep 2020 23:31:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C5F5621775 for ; Mon, 28 Sep 2020 23:31:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601335872; bh=AuTy7tGMkG8gJzgNl9lfYfB9FwNBH9eZew6Rscmgudw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=VAEmVvONe4166RbiKtGZHCfoq56uQowQwmIor0ETjAymWawTGGJTg5PuveOmo6Ni/ agFQ7xwn/t//gn4vEr1tNUd+tWXo+mzDZDVPDN1OfkJYQLl3IJ95pgfADYFl5ulWRM ZjlYFyROP+GFtTFiGF1HHYSGj3MWOs6akBr9yN+Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727256AbgI1XbL (ORCPT ); Mon, 28 Sep 2020 19:31:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:54292 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727210AbgI1XbF (ORCPT ); Mon, 28 Sep 2020 19:31:05 -0400 Received: from paulmck-ThinkPad-P72.home (unknown [50.45.173.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BB0BD21D43; Mon, 28 Sep 2020 23:31:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601335864; bh=AuTy7tGMkG8gJzgNl9lfYfB9FwNBH9eZew6Rscmgudw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=St7E+3398t135547ZTAV7d9yGDqXB/LD/PIAHTT5Aly7GP7S5puG+FntxYT7/JitX sdy+Qq2x5f2b/VKgoF2Tw3DXrzjpB8eiYrl2UHnj8nfMAj1j1oWxWm3+MmahwI28AZ GrjM8kUy5fzhE9AtWisvUFcbevpCMdVf2p1npAYA= From: paulmck@kernel.org To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, mhocko@kernel.org, mgorman@techsingularity.net, torvalds@linux-foundation.org, Juri Lelli , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , "Paul E . McKenney" Subject: [PATCH tip/core/rcu 03/15] preempt: Cleanup PREEMPT_COUNT leftovers Date: Mon, 28 Sep 2020 16:30:50 -0700 Message-Id: <20200928233102.24265-3-paulmck@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20200928233041.GA23230@paulmck-ThinkPad-P72> References: <20200928233041.GA23230@paulmck-ThinkPad-P72> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner CONFIG_PREEMPT_COUNT is now unconditionally enabled and will be removed. Cleanup the leftovers before doing so. Signed-off-by: Thomas Gleixner Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Juri Lelli Cc: Vincent Guittot Cc: Dietmar Eggemann Cc: Steven Rostedt Cc: Ben Segall Cc: Mel Gorman Cc: Daniel Bristot de Oliveira Signed-off-by: Paul E. McKenney --- include/linux/preempt.h | 37 ++++--------------------------------- 1 file changed, 4 insertions(+), 33 deletions(-) diff --git a/include/linux/preempt.h b/include/linux/preempt.h index 7d9c1c0..513769b 100644 --- a/include/linux/preempt.h +++ b/include/linux/preempt.h @@ -56,8 +56,7 @@ #define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) /* - * Disable preemption until the scheduler is running -- use an unconditional - * value so that it also works on !PREEMPT_COUNT kernels. + * Disable preemption until the scheduler is running. * * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count(). */ @@ -69,7 +68,6 @@ * * preempt_count() == 2*PREEMPT_DISABLE_OFFSET * - * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels. * Note: See finish_task_switch(). */ #define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) @@ -106,11 +104,7 @@ /* * The preempt_count offset after preempt_disable(); */ -#if defined(CONFIG_PREEMPT_COUNT) -# define PREEMPT_DISABLE_OFFSET PREEMPT_OFFSET -#else -# define PREEMPT_DISABLE_OFFSET 0 -#endif +#define PREEMPT_DISABLE_OFFSET PREEMPT_OFFSET /* * The preempt_count offset after spin_lock() @@ -122,8 +116,8 @@ * * spin_lock_bh() * - * Which need to disable both preemption (CONFIG_PREEMPT_COUNT) and - * softirqs, such that unlock sequences of: + * Which need to disable both preemption and softirqs, such that unlock + * sequences of: * * spin_unlock(); * local_bh_enable(); @@ -164,8 +158,6 @@ extern void preempt_count_sub(int val); #define preempt_count_inc() preempt_count_add(1) #define preempt_count_dec() preempt_count_sub(1) -#ifdef CONFIG_PREEMPT_COUNT - #define preempt_disable() \ do { \ preempt_count_inc(); \ @@ -231,27 +223,6 @@ do { \ __preempt_count_dec(); \ } while (0) -#else /* !CONFIG_PREEMPT_COUNT */ - -/* - * Even if we don't have any preemption, we need preempt disable/enable - * to be barriers, so that we don't have things like get_user/put_user - * that can cause faults and scheduling migrate into our preempt-protected - * region. - */ -#define preempt_disable() barrier() -#define sched_preempt_enable_no_resched() barrier() -#define preempt_enable_no_resched() barrier() -#define preempt_enable() barrier() -#define preempt_check_resched() do { } while (0) - -#define preempt_disable_notrace() barrier() -#define preempt_enable_no_resched_notrace() barrier() -#define preempt_enable_notrace() barrier() -#define preemptible() 0 - -#endif /* CONFIG_PREEMPT_COUNT */ - #ifdef MODULE /* * Modules have no business playing preemption tricks. -- 2.9.5