Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756188AbZFLG4V (ORCPT ); Fri, 12 Jun 2009 02:56:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755900AbZFLG4D (ORCPT ); Fri, 12 Jun 2009 02:56:03 -0400 Received: from mx2.redhat.com ([66.187.237.31]:48713 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755778AbZFLG4A (ORCPT ); Fri, 12 Jun 2009 02:56:00 -0400 Date: Fri, 12 Jun 2009 08:49:27 +0200 From: Stanislaw Gruszka To: Thomas Gleixner Cc: "linux-kernel@vger.kernel.org" , Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Andrew Morton Subject: [PATCH 2/2] posix-cpu-timers: remove tasklist_lock where we can Message-ID: <20090612084927.11673956@dhcp-lab-109.englab.brq.redhat.com> Organization: RedHat Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1566 Lines: 54 tasklist_lock is not needed to protect find_task_by_vpid() nor thread_group_leader() nor same_thread_group() , use rcu_read_lock() instead. Signed-off-by: Stanislaw Gruszka --- kernel/posix-cpu-timers.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index bece7c0..1d9cdf3 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -37,13 +37,13 @@ static int check_clock(const clockid_t which_clock) if (pid == 0) return 0; - read_lock(&tasklist_lock); + rcu_read_lock(); p = find_task_by_vpid(pid); if (!p || !(CPUCLOCK_PERTHREAD(which_clock) ? same_thread_group(p, current) : thread_group_leader(p))) { error = -EINVAL; } - read_unlock(&tasklist_lock); + rcu_read_lock(); return error; } @@ -398,7 +398,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer) new_timer->it.cpu.incr.sched = 0; new_timer->it.cpu.expires.sched = 0; - read_lock(&tasklist_lock); + rcu_read_lock(); if (CPUCLOCK_PERTHREAD(new_timer->it_clock)) { if (pid == 0) { p = current; @@ -422,7 +422,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer) } else { ret = -EINVAL; } - read_unlock(&tasklist_lock); + rcu_read_unlock(); return ret; } -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/