From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 263A9C433F5 for ; Thu, 6 Sep 2018 08:17:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6DCA2083D for ; Thu, 6 Sep 2018 08:17:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D6DCA2083D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728076AbeIFMvt (ORCPT ); Thu, 6 Sep 2018 08:51:49 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:40293 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725819AbeIFMvt (ORCPT ); Thu, 6 Sep 2018 08:51:49 -0400 Received: by mail-wr1-f68.google.com with SMTP id n2-v6so10358738wrw.7 for ; Thu, 06 Sep 2018 01:17:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=OcUD6zyFubkDVhsmPCCCASObW8UUhxp/Hh/diNtVEmg=; b=SHM8ipMLCvTPnk/+2FulyrAqa3173qRgsaUuWSo8QsYdJZ3VWVNcJS7BJosoCmEoow +bVSF420fDiDvfJKarXmZRhLClBf3RzqBgo4VLZPZtb6xPuAtRIggDsTFlg6VIPusCoC z/5Vc5O1m8RSr25mBI6bNFpwJBVUnJA511TeIULJJLlhyhNNyRbf4hge1sQCozmwCo2E QEstgek7PdSwvJ282tm1waUaF2C1irt03DrX9ks+vwIv3wQeSIwVl1mMaV1gdzTqCi+Z W+vyGK0+GARZaJKna/fVTumIR1TRJRGWiFP6FXTaQ8z5KhmNIFiqyeR+1Qr2jneA5jNU Rojg== X-Gm-Message-State: APzg51D9GM4A7b71zVv+gVn+gUyZ24BI/3Y34zIvh+6uYnaTCSEejNLE 9V6kkDcrB1e76XGazzbWQz7qLg== X-Google-Smtp-Source: ANB0Vdbd8cF+3mEuY8S0hsIqRjrbnDZuWxSj+U83RJVL1pAa3XAhI/b/4C1nrW1goaCXuOn5PAV26A== X-Received: by 2002:adf:ea92:: with SMTP id s18-v6mr1291427wrm.284.1536221851665; Thu, 06 Sep 2018 01:17:31 -0700 (PDT) Received: from localhost.localdomain ([151.15.227.30]) by smtp.gmail.com with ESMTPSA id 200-v6sm6790961wmv.6.2018.09.06.01.17.29 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 06 Sep 2018 01:17:30 -0700 (PDT) Date: Thu, 6 Sep 2018 10:17:28 +0200 From: Juri Lelli To: Patrick Bellasi Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Ingo Molnar , Peter Zijlstra , Tejun Heo , "Rafael J . Wysocki" , Viresh Kumar , Vincent Guittot , Paul Turner , Quentin Perret , Dietmar Eggemann , Morten Rasmussen , Todd Kjos , Joel Fernandes , Steve Muckle , Suren Baghdasaryan Subject: Re: [PATCH v4 02/16] sched/core: uclamp: map TASK's clamp values into CPU's clamp groups Message-ID: <20180906081728.GB27626@localhost.localdomain> References: <20180828135324.21976-1-patrick.bellasi@arm.com> <20180828135324.21976-3-patrick.bellasi@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180828135324.21976-3-patrick.bellasi@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 28/08/18 14:53, Patrick Bellasi wrote: [...] > static inline int __setscheduler_uclamp(struct task_struct *p, > const struct sched_attr *attr) > { > - if (attr->sched_util_min > attr->sched_util_max) > - return -EINVAL; > - if (attr->sched_util_max > SCHED_CAPACITY_SCALE) > - return -EINVAL; > + int group_id[UCLAMP_CNT] = { UCLAMP_NOT_VALID }; > + int lower_bound, upper_bound; > + struct uclamp_se *uc_se; > + int result = 0; > > - p->uclamp[UCLAMP_MIN] = attr->sched_util_min; > - p->uclamp[UCLAMP_MAX] = attr->sched_util_max; > + mutex_lock(&uclamp_mutex); > > - return 0; > + /* Find a valid group_id for each required clamp value */ > + if (attr->sched_flags & SCHED_FLAG_UTIL_CLAMP_MIN) { > + upper_bound = (attr->sched_flags & SCHED_FLAG_UTIL_CLAMP_MAX) > + ? attr->sched_util_max > + : p->uclamp[UCLAMP_MAX].value; > + > + if (upper_bound == UCLAMP_NOT_VALID) > + upper_bound = SCHED_CAPACITY_SCALE; > + if (attr->sched_util_min > upper_bound) { > + result = -EINVAL; > + goto done; > + } > + > + result = uclamp_group_find(UCLAMP_MIN, attr->sched_util_min); > + if (result == -ENOSPC) { > + pr_err(UCLAMP_ENOSPC_FMT, "MIN"); > + goto done; > + } > + group_id[UCLAMP_MIN] = result; > + } > + if (attr->sched_flags & SCHED_FLAG_UTIL_CLAMP_MAX) { > + lower_bound = (attr->sched_flags & SCHED_FLAG_UTIL_CLAMP_MIN) > + ? attr->sched_util_min > + : p->uclamp[UCLAMP_MIN].value; > + > + if (lower_bound == UCLAMP_NOT_VALID) > + lower_bound = 0; > + if (attr->sched_util_max < lower_bound || > + attr->sched_util_max > SCHED_CAPACITY_SCALE) { > + result = -EINVAL; > + goto done; > + } > + > + result = uclamp_group_find(UCLAMP_MAX, attr->sched_util_max); > + if (result == -ENOSPC) { > + pr_err(UCLAMP_ENOSPC_FMT, "MAX"); > + goto done; > + } > + group_id[UCLAMP_MAX] = result; > + } Don't you have to reset result to 0 here (it seems what follows cannot fail anymore)? Otherwise this function will return latest uclamp_group_find return value, which will be interpreted as error if not 0. > + > + /* Update each required clamp group */ > + if (attr->sched_flags & SCHED_FLAG_UTIL_CLAMP_MIN) { > + uc_se = &p->uclamp[UCLAMP_MIN]; > + uclamp_group_get(UCLAMP_MIN, group_id[UCLAMP_MIN], > + uc_se, attr->sched_util_min); > + } > + if (attr->sched_flags & SCHED_FLAG_UTIL_CLAMP_MAX) { > + uc_se = &p->uclamp[UCLAMP_MAX]; > + uclamp_group_get(UCLAMP_MAX, group_id[UCLAMP_MAX], > + uc_se, attr->sched_util_max); > + } > + > +done: > + mutex_unlock(&uclamp_mutex); > + > + return result; > +} Best, - Juri