From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754534Ab2A3XPB (ORCPT ); Mon, 30 Jan 2012 18:15:01 -0500 Received: from e28smtp01.in.ibm.com ([122.248.162.1]:58357 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752676Ab2A3XO7 (ORCPT ); Mon, 30 Jan 2012 18:14:59 -0500 From: "Srivatsa S. Bhat" Subject: [PATCH v2 2/4] PM/Freezer: Make thaw_processes() thaw only userspace tasks To: rjw@sisk.pl Cc: pavel@ucw.cz, len.brown@intel.com, tj@kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, "Srivatsa S. Bhat" Date: Tue, 31 Jan 2012 04:44:48 +0530 Message-ID: <20120130231437.11129.3708.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20120130231342.11129.87187.stgit@srivatsabhat.in.ibm.com> References: <20120130231342.11129.87187.stgit@srivatsabhat.in.ibm.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit x-cbid: 12013023-4790-0000-0000-00000118E062 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently the situation is: freeze_processes() - freezes only userspace tasks freeze_kernel_threads() - freezes only kernel threads thaw_kernel_threads() - thaws only kernel threads thaw_processes() - thaws *everything* (both userspace tasks and kernel threads) The point that thaw_processes() thaws everything is rather unintuitive and can lead to bugs. So, modify thaw_processes() so that it thaws only userspace processes. This way we can also have more control over what exactly gets thawed in different situations. Signed-off-by: Srivatsa S. Bhat --- kernel/power/process.c | 9 ++++----- 1 files changed, 4 insertions(+), 5 deletions(-) diff --git a/kernel/power/process.c b/kernel/power/process.c index 3734fb9..8ae6c4b 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -116,7 +116,8 @@ static int try_to_freeze_tasks(bool user_only) /** * freeze_processes - Signal user space processes to enter the refrigerator. * - * On success, returns 0. On failure, -errno and system is fully thawed. + * On success, returns 0. On failure, -errno and all user space processes + * are thawed. */ int freeze_processes(void) { @@ -170,17 +171,15 @@ void thaw_processes(void) if (pm_freezing) atomic_dec(&system_freezing_cnt); pm_freezing = false; - pm_nosig_freezing = false; oom_killer_enable(); printk("Restarting tasks ... "); - thaw_workqueues(); - read_lock(&tasklist_lock); do_each_thread(g, p) { - __thaw_task(p); + if (!(p->flags & (PF_KTHREAD | PF_WQ_WORKER))) + __thaw_task(p); } while_each_thread(g, p); read_unlock(&tasklist_lock);