Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754902Ab1DVM1A (ORCPT ); Fri, 22 Apr 2011 08:27:00 -0400 Received: from arkanian.console-pimps.org ([212.110.184.194]:51602 "EHLO arkanian.console-pimps.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751977Ab1DVM07 (ORCPT ); Fri, 22 Apr 2011 08:26:59 -0400 Date: Fri, 22 Apr 2011 13:26:57 +0100 From: Matt Fleming To: Oleg Nesterov Cc: Tejun Heo , Linus Torvalds , Andrew Morton , "Nikita V. Youshchenko" , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/7] signal: retarget_shared_pending: optimize while_each_thread() loop Message-ID: <20110422132657.646f1774@mfleming-mobl1.ger.corp.intel.com> In-Reply-To: <20110418134518.GD15951@redhat.com> References: <20110418134421.GA15951@redhat.com> <20110418134518.GD15951@redhat.com> X-Mailer: Claws Mail 3.7.8cvs52 (GTK+ 2.22.0; x86_64-unknown-linux-gnu) 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: 855 Lines: 22 On Mon, 18 Apr 2011 15:45:18 +0200 Oleg Nesterov wrote: > retarget_shared_pending() blindly does recalc_sigpending_and_wake() for > every sub-thread, this is suboptimal. We can check t->blocked and stop > looping once every bit in shared_pending has the new target. > > Note: we do not take task_is_stopped_or_traced(t) into account, we are > not trying to speed up the signal delivery or to avoid the unnecessary > (but harmless) signal_wake_up(0) in this unlikely case. > > Signed-off-by: Oleg Nesterov Nice. Reviewed-by: Matt Fleming -- 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/