From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753749AbdEQPUk (ORCPT ); Wed, 17 May 2017 11:20:40 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:36293 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750969AbdEQPUg (ORCPT ); Wed, 17 May 2017 11:20:36 -0400 From: Karim Eshapa To: corbet@lwn.net Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Karim Eshapa Subject: [PATCH] Documentation: scheduler: sched-arch: remove __ARCH_WANT_UNLOCKED_CTXSW macro Date: Wed, 17 May 2017 17:20:28 +0200 Message-Id: <1495034428-6734-1-git-send-email-karim.eshapa@gmail.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org remove __ARCH_WANT_UNLOCKED_CTXSW macro because it's no longer exist after 3.17.8 kernel release. Signed-off-by: Karim Eshapa --- Documentation/scheduler/sched-arch.txt | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/Documentation/scheduler/sched-arch.txt b/Documentation/scheduler/sched-arch.txt index a2f27bb..36ed0b4 100644 --- a/Documentation/scheduler/sched-arch.txt +++ b/Documentation/scheduler/sched-arch.txt @@ -6,16 +6,11 @@ Context switch ============== 1. Runqueue locking By default, the switch_to arch function is called with the runqueue -locked. This is usually not a problem unless switch_to may need to -take the runqueue lock. This is usually due to a wake up operation in -the context switch. See arch/ia64/include/asm/switch_to.h for an example. - -To request the scheduler call switch_to with the runqueue unlocked, -you must `#define __ARCH_WANT_UNLOCKED_CTXSW` in a header file -(typically the one where switch_to is defined). - -Unlocked context switches introduce only a very minor performance -penalty to the core scheduler implementation in the CONFIG_SMP case. +locked. This is usually due to a wake up operation in the context +switch.The schedular call switch_to became with runqueue unlocked +such that use rq_unpin_lock(), spin_release() that warn for locking +bugs (lock inversion, circular lock dependencies,..) and release +lockdep respectively. CPU idle ======== -- 2.7.4