From patchwork Tue Apr 23 12:51:41 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Lezcano X-Patchwork-Id: 16350 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-qe0-f70.google.com (mail-qe0-f70.google.com [209.85.128.70]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id 88D672391B for ; Tue, 23 Apr 2013 12:52:36 +0000 (UTC) Received: by mail-qe0-f70.google.com with SMTP id 1sf1177545qec.5 for ; Tue, 23 Apr 2013 05:51:47 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:x-beenthere:x-received:received-spf:x-received :x-forwarded-to:x-forwarded-for:delivered-to:x-received:received-spf :x-received:message-id:date:from:user-agent:mime-version:to:cc :subject:references:in-reply-to:x-gm-message-state:x-original-sender :x-original-authentication-results:precedence:mailing-list:list-id :x-google-group-id:list-post:list-help:list-archive:list-unsubscribe :content-type:content-transfer-encoding; bh=jQVHYdcfvFnCqECv8biSlFGGCesr4EU/ovxXi4QOxdw=; b=FExtcwNSk9AWvm5/9IYJ2jdmZFIboH6AweWSszwoHalk451bBfJXur/fqZ8ufhYcAI U3lQXdFrr2Gn8AI6CPDZ97vCN0dTd+BdPmvXJYDgk2G4H3n58EnrIjQzzaYyT3T/rrcg 9EMVLN2LgBd2Q8AwYLuTjnRSlQldiECidJIgLV4Nsv7GyJFiSbzFZB93dAdGGCdWe+it myvkiplpkIwDKulhIbtjX9SPFCPpZKDpqEfX/1wn1JTHzCY4L4VOkeQORZmYRG2PvXMs wrRzRpmOHNrAdbOntn7wKGOUm5jEhEAD8jJSOWAXidnlRw8CnQrQqIEowLC5Ur+u9TJe IhCQ== X-Received: by 10.236.145.131 with SMTP id p3mr15157868yhj.6.1366721507706; Tue, 23 Apr 2013 05:51:47 -0700 (PDT) X-BeenThere: patchwork-forward@linaro.org Received: by 10.49.117.101 with SMTP id kd5ls293229qeb.45.gmail; Tue, 23 Apr 2013 05:51:47 -0700 (PDT) X-Received: by 10.58.145.162 with SMTP id sv2mr2995856veb.1.1366721507477; Tue, 23 Apr 2013 05:51:47 -0700 (PDT) Received: from mail-vb0-x232.google.com (mail-vb0-x232.google.com [2607:f8b0:400c:c02::232]) by mx.google.com with ESMTPS id j11si18416688vcw.5.2013.04.23.05.51.47 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 23 Apr 2013 05:51:47 -0700 (PDT) Received-SPF: neutral (google.com: 2607:f8b0:400c:c02::232 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) client-ip=2607:f8b0:400c:c02::232; Received: by mail-vb0-f50.google.com with SMTP id w16so519086vbb.37 for ; Tue, 23 Apr 2013 05:51:47 -0700 (PDT) X-Received: by 10.52.71.4 with SMTP id q4mr18819489vdu.8.1366721507351; Tue, 23 Apr 2013 05:51:47 -0700 (PDT) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patches@linaro.org Received: by 10.58.127.98 with SMTP id nf2csp123727veb; Tue, 23 Apr 2013 05:51:46 -0700 (PDT) X-Received: by 10.194.92.197 with SMTP id co5mr30877791wjb.41.1366721506255; Tue, 23 Apr 2013 05:51:46 -0700 (PDT) Received: from mail-ee0-f49.google.com (mail-ee0-f49.google.com [74.125.83.49]) by mx.google.com with ESMTPS id v7si3515807eep.108.2013.04.23.05.51.45 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 23 Apr 2013 05:51:46 -0700 (PDT) Received-SPF: neutral (google.com: 74.125.83.49 is neither permitted nor denied by best guess record for domain of daniel.lezcano@linaro.org) client-ip=74.125.83.49; Received: by mail-ee0-f49.google.com with SMTP id d4so237446eek.36 for ; Tue, 23 Apr 2013 05:51:45 -0700 (PDT) X-Received: by 10.15.31.197 with SMTP id y45mr51039716eeu.18.1366721505551; Tue, 23 Apr 2013 05:51:45 -0700 (PDT) Received: from [192.168.1.150] (AToulouse-654-1-479-219.w86-201.abo.wanadoo.fr. [86.201.194.219]) by mx.google.com with ESMTPS id b5sm46755056eew.16.2013.04.23.05.51.42 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 23 Apr 2013 05:51:44 -0700 (PDT) Message-ID: <517683DD.6060805@linaro.org> Date: Tue, 23 Apr 2013 14:51:41 +0200 From: Daniel Lezcano User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: Santosh Shilimkar CC: rjw@sisk.pl, andrew@lunn.ch, kgene.kim@samsung.com, jason@lakedaemon.net, horms@verge.net.au, patches@linaro.org, khilman@deeprootsystems.com, magnus.damm@gmail.com, linux-pm@vger.kernel.org, swarren@wwwdotorg.org, nsekhar@ti.com, rob.herring@calxeda.com, deepthi@linux.vnet.ibm.com, tony@atomide.com, lethal@linux-sh.org, linaro-kernel@lists.linaro.org, kernel@pengutronix.de, josephl@nvidia.com, jkosina@suse.cz, plagnioj@jcrosoft.com, linux@maxim.org.za, linux-arm-kernel@lists.infradead.org Subject: Re: [V4 patch 03/15] cpuidle: make a single register function for all References: <1366707285-12179-1-git-send-email-daniel.lezcano@linaro.org> <1366707285-12179-4-git-send-email-daniel.lezcano@linaro.org> <51767F57.7060809@ti.com> In-Reply-To: <51767F57.7060809@ti.com> X-Gm-Message-State: ALoCoQk6H+RVyFO3J7Tlso1Vd2IS9T+pZ11xhf0tZvODDNj5tCkqjdrs6PimlKNcwtNxkLZg9QY5 X-Original-Sender: daniel.lezcano@linaro.org X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 2607:f8b0:400c:c02::232 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org Precedence: list Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org List-ID: X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , On 04/23/2013 02:32 PM, Santosh Shilimkar wrote: > On Tuesday 23 April 2013 02:24 PM, Daniel Lezcano wrote: >> The usual scheme to initialize a cpuidle driver on a SMP is: >> >> cpuidle_register_driver(drv); >> for_each_possible_cpu(cpu) { >> device = &per_cpu(cpuidle_dev, cpu); >> cpuidle_register_device(device); >> } >> >> This code is duplicated in each cpuidle driver. >> >> On UP systems, it is done this way: >> >> cpuidle_register_driver(drv); >> device = &per_cpu(cpuidle_dev, cpu); >> cpuidle_register_device(device); >> >> On UP, the macro 'for_each_cpu' does one iteration: >> >> #define for_each_cpu(cpu, mask) \ >> for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) >> >> Hence, the initialization loop is the same for UP than SMP. >> >> Beside, we saw different bugs / mis-initialization / return code unchecked in >> the different drivers, the code is duplicated including bugs. After fixing all >> these ones, it appears the initialization pattern is the same for everyone. >> >> Please note, some drivers are doing dev->state_count = drv->state_count. This is >> not necessary because it is done by the cpuidle_enable_device function in the >> cpuidle framework. This is true, until you have the same states for all your >> devices. Otherwise, the 'low level' API should be used instead with the specific >> initialization for the driver. >> >> Let's add a wrapper function doing this initialization with a cpumask parameter >> for the coupled idle states and use it for all the drivers. >> >> That will save a lot of LOC, consolidate the code, and the modifications in the >> future could be done in a single place. Another benefit is the consolidation of >> the cpuidle_device variable which is now in the cpuidle framework and no longer >> spread accross the different arch specific drivers. >> >> Signed-off-by: Daniel Lezcano >> --- > > I don't see you have addressed the comment on V3 [1] i gave for the subject patch > Any reason ? Yes, sorry for not answering. This modification should be handled in the __cpuidle_register_device function. per_cpu(cpuidle_devices, dev->cpu) = dev; Thus, the cpuidle_register function is not impacted by this as it will always do cpuidle_register_driver, followed by cpuidle_register_device. -- Daniel diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 49e8d30..936d862 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -372,7 +372,7 @@ static int __cpuidle_register_device(struct cpuidle_device *dev) int ret; struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); - if (!try_module_get(drv->owner)) + if (!drv || !try_module_get(drv->owner)) return -EINVAL;