Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753482AbaBTLJi (ORCPT ); Thu, 20 Feb 2014 06:09:38 -0500 Received: from www.linutronix.de ([62.245.132.108]:58365 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752885AbaBTLJh (ORCPT ); Thu, 20 Feb 2014 06:09:37 -0500 Date: Thu, 20 Feb 2014 12:09:43 +0100 (CET) From: Thomas Gleixner To: Alexey Perevalov cc: linux-kernel@vger.kernel.org, john.stultz@linaro.org, Anton Vorontsov , anton@nomsg.org, kyungmin.park@samsung.com, cw00.choi@samsung.com, akpm@linux-foundation.org, Anton Vorontsov Subject: Re: [PATCH v3 5/6] timerfd: Add support for deferrable timers In-Reply-To: <1392885633-7787-6-git-send-email-a.perevalov@samsung.com> Message-ID: References: <1392885633-7787-1-git-send-email-a.perevalov@samsung.com> <1392885633-7787-6-git-send-email-a.perevalov@samsung.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 20 Feb 2014, Alexey Perevalov wrote: > From: Anton Vorontsov > > This patch implements a userland-side API for generic deferrable timers, > per linux/timer.h: > > * A deferrable timer will work normally when the system is busy, but > * will not cause a CPU to come out of idle just to service it; instead, > * the timer will be serviced when the CPU eventually wakes up with a > * subsequent non-deferrable timer. > > These timers are crucial for power saving, i.e. periodic tasks that want > to work in background when the system is under use, but don't want to > cause wakeups themselves. > > The deferred timers are somewhat orthogonal to high-res external timers, > since the deferred timer is tied to the system load, not just to some > external decrementer source. Again this changelog makes no sense. What's orthogonal to high-res timers and why are they external? So 5 out of 6 patches are a trainwreck in various degrees of wreckage. A pretty impressive achievement. Thanks, tglx -- 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/