From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey Starikovskiy Subject: Re: [PATCH -V2] acpi: don't cond_resched if irq is disabled Date: Mon, 28 Dec 2009 14:12:33 +0300 Message-ID: <4B3892A1.9010303@suse.de> References: <20091210100907.GA2446@ucw.cz> <1260446205-16868-1-git-send-email-dfeng@redhat.com> <4B20E7B2.1010208@suse.de> <1260510373.10543.17.camel@minggr.sh.intel.com> <4B223185.80202@suse.de> <20091211161549.GA15760@elf.ucw.cz> <4B227275.5010201@gmail.com> <20091211173424.GC15760@elf.ucw.cz> <4B3849F6.1080403@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from nat.nue.novell.com ([195.135.221.3]:58903 "EHLO emea5-mh.id5.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751168AbZL1LMf (ORCPT ); Mon, 28 Dec 2009 06:12:35 -0500 In-Reply-To: <4B3849F6.1080403@redhat.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Xiaotian Feng Cc: Pavel Machek , Alexey Starikovskiy , Lin Ming , "linux-acpi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Len Brown , "Moore, Robert" Xiaotian Feng =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > On 12/12/2009 01:34 AM, Pavel Machek wrote: >> >>>>> If there are none, fine. >>>>> >>>>>> #ifdef CONFIG_PREEMPT >>>>>> # define preemptible() (preempt_count() =3D=3D 0&& !irqs_disab= led()) >>>>>> # define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1) >>>>>> #else >>>>>> # define preemptible() 0 >>>>>> # define IRQ_EXIT_OFFSET HARDIRQ_OFFSET >>>>>> #endif >>>>>> >>>> >>>> Well, normally we want low latency even for !CONFIG_PREEMPT kernel= s. >>>> >>>> Actually, explicit preemption points are NOPs for CONFIG_PREEMPT >>>> kernels, right? >> >>> Right. Do you have code? >> >> I'd prefer to spend my time with patches to areas that actually do >> take cleanup patches. >=20 > What's the status of this now? We can still see the sleeping function > call warning or enable irq at resume stage. > If acpi wants low latency even for !CONFIG_PREEMPT kernels, what's wr= ong > with V2 patch? >=20 > We should not set any preemption points in irq or atomic. Since we ha= ve > a simple fix, and it did fix bugs, why should > we make things more complex? We should not do anything complex here, you are right. Consider me ACK your patch. Thanks, Alex -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752537AbZL1LMi (ORCPT ); Mon, 28 Dec 2009 06:12:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751670AbZL1LMf (ORCPT ); Mon, 28 Dec 2009 06:12:35 -0500 Received: from nat.nue.novell.com ([195.135.221.3]:58903 "EHLO emea5-mh.id5.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751168AbZL1LMf (ORCPT ); Mon, 28 Dec 2009 06:12:35 -0500 Message-ID: <4B3892A1.9010303@suse.de> Date: Mon, 28 Dec 2009 14:12:33 +0300 From: Alexey Starikovskiy User-Agent: Thunderbird 2.0.0.23 (X11/20090817) MIME-Version: 1.0 To: Xiaotian Feng CC: Pavel Machek , Alexey Starikovskiy , Lin Ming , "linux-acpi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Len Brown , "Moore, Robert" Subject: Re: [PATCH -V2] acpi: don't cond_resched if irq is disabled References: <20091210100907.GA2446@ucw.cz> <1260446205-16868-1-git-send-email-dfeng@redhat.com> <4B20E7B2.1010208@suse.de> <1260510373.10543.17.camel@minggr.sh.intel.com> <4B223185.80202@suse.de> <20091211161549.GA15760@elf.ucw.cz> <4B227275.5010201@gmail.com> <20091211173424.GC15760@elf.ucw.cz> <4B3849F6.1080403@redhat.com> In-Reply-To: <4B3849F6.1080403@redhat.com> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Xiaotian Feng пишет: > On 12/12/2009 01:34 AM, Pavel Machek wrote: >> >>>>> If there are none, fine. >>>>> >>>>>> #ifdef CONFIG_PREEMPT >>>>>> # define preemptible() (preempt_count() == 0&& !irqs_disabled()) >>>>>> # define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1) >>>>>> #else >>>>>> # define preemptible() 0 >>>>>> # define IRQ_EXIT_OFFSET HARDIRQ_OFFSET >>>>>> #endif >>>>>> >>>> >>>> Well, normally we want low latency even for !CONFIG_PREEMPT kernels. >>>> >>>> Actually, explicit preemption points are NOPs for CONFIG_PREEMPT >>>> kernels, right? >> >>> Right. Do you have code? >> >> I'd prefer to spend my time with patches to areas that actually do >> take cleanup patches. > > What's the status of this now? We can still see the sleeping function > call warning or enable irq at resume stage. > If acpi wants low latency even for !CONFIG_PREEMPT kernels, what's wrong > with V2 patch? > > We should not set any preemption points in irq or atomic. Since we have > a simple fix, and it did fix bugs, why should > we make things more complex? We should not do anything complex here, you are right. Consider me ACK your patch. Thanks, Alex