From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752696AbbKOShW (ORCPT ); Sun, 15 Nov 2015 13:37:22 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40548 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752633AbbKOShT (ORCPT ); Sun, 15 Nov 2015 13:37:19 -0500 Date: Sun, 15 Nov 2015 20:33:20 +0100 From: Oleg Nesterov To: Ingo Molnar , Peter Zijlstra Cc: Milos Vyletel , Prarit Bhargava , Tejun Heo , Thomas Gleixner , linux-kernel@vger.kernel.org Subject: [PATCH 4/8] stop_machine: change stop_one_cpu() to rely on cpu_stop_queue_work() Message-ID: <20151115193320.GA8259@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151115193254.GA8225@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Change stop_one_cpu() to return -ENOENT if cpu_stop_queue_work() fails. Otherwise we know that ->executed must be true after wait_for_completion() so we can just return done.ret. Signed-off-by: Oleg Nesterov --- kernel/stop_machine.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 0ec1f16..68b73c4 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -128,9 +128,11 @@ int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg) struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done }; cpu_stop_init_done(&done, 1); - cpu_stop_queue_work(cpu, &work); + if (!cpu_stop_queue_work(cpu, &work)) + return -ENOENT; wait_for_completion(&done.completion); - return done.executed ? done.ret : -ENOENT; + WARN_ON(!done.executed); + return done.ret; } /* This controls the threads on each CPU. */ -- 1.5.5.1