From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756282AbaCYRzc (ORCPT ); Tue, 25 Mar 2014 13:55:32 -0400 Received: from cantor2.suse.de ([195.135.220.15]:58434 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755004AbaCYRzP (ORCPT ); Tue, 25 Mar 2014 13:55:15 -0400 From: Jan Kara To: Andrew Morton Cc: LKML , pmladek@suse.cz, Frederic Weisbecker , Steven Rostedt , Jan Kara Subject: [PATCH 1/8] printk: Remove outdated comment Date: Tue, 25 Mar 2014 18:54:54 +0100 Message-Id: <1395770101-24534-2-git-send-email-jack@suse.cz> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1395770101-24534-1-git-send-email-jack@suse.cz> References: <1395770101-24534-1-git-send-email-jack@suse.cz> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Comment about interesting interlocking between lockbuf_lock and console_sem is outdated. It was added in 2002 by commit a880f45a48be2956d2c78a839c472287d54435c1 during conversion of console_lock to console_sem + lockbuf_lock. At that time release_console_sem() (today's equivalent is console_unlock()) was indeed using lockbuf_lock to avoid races between trylock on console_sem in printk() and unlock of console_sem. However these days the interlocking is gone and the races are avoided by rechecking logbuf state after releasing console_sem. Signed-off-by: Jan Kara --- kernel/printk/printk.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 4dae9cbe9259..bd7ee2a9f960 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -206,8 +206,7 @@ struct printk_log { }; /* - * The logbuf_lock protects kmsg buffer, indices, counters. It is also - * used in interesting ways to provide interlocking in console_unlock(); + * The logbuf_lock protects kmsg buffer, indices, counters. */ static DEFINE_RAW_SPINLOCK(logbuf_lock); -- 1.8.1.4