From mboxrd@z Thu Jan 1 00:00:00 1970 From: Preeti U Murthy Subject: Re: [PATCH V2 10/10] cpufreq: propagate errors returned from __cpufreq_governor() Date: Fri, 19 Jun 2015 23:32:24 +0530 Message-ID: <55845930.7020503@linux.vnet.ibm.com> References: <46b51eea20399c927fb1f16839773f618133ae09.1434713657.git.viresh.kumar@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-6 Content-Transfer-Encoding: 7bit Return-path: Received: from e19.ny.us.ibm.com ([129.33.205.209]:51860 "EHLO e19.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755411AbbFSSC4 (ORCPT ); Fri, 19 Jun 2015 14:02:56 -0400 Received: from /spool/local by e19.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 19 Jun 2015 14:02:55 -0400 Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id D7920C9004A for ; Fri, 19 Jun 2015 13:53:58 -0400 (EDT) Received: from d01av03.pok.ibm.com (d01av03.pok.ibm.com [9.56.224.217]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t5JI2qSK62455902 for ; Fri, 19 Jun 2015 18:02:52 GMT Received: from d01av03.pok.ibm.com (localhost [127.0.0.1]) by d01av03.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t5JI2nbS028763 for ; Fri, 19 Jun 2015 14:02:51 -0400 In-Reply-To: <46b51eea20399c927fb1f16839773f618133ae09.1434713657.git.viresh.kumar@linaro.org> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Viresh Kumar , Rafael Wysocki , ke.wang@spreadtrum.com Cc: linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org, ego@linux.vnet.ibm.com, paulus@samba.org, shilpa.bhat@linux.vnet.ibm.com, prarit@redhat.com, robert.schoene@tu-dresden.de, skannan@codeaurora.org On 06/19/2015 05:18 PM, Viresh Kumar wrote: > Return codes aren't honored properly in cpufreq_set_policy(). This can > lead to two problems: > - wrong errors propagated to sysfs > - we try to do next state-change even if the previous one failed > > cpufreq_governor_dbs() now returns proper errors on all invalid > state-transition requests and this code should honor that. > > Signed-off-by: Viresh Kumar Minor points below. > --- > drivers/cpufreq/cpufreq.c | 22 +++++++++++++--------- > 1 file changed, 13 insertions(+), 9 deletions(-) > > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > index b612411655f9..da672b910760 100644 > --- a/drivers/cpufreq/cpufreq.c > +++ b/drivers/cpufreq/cpufreq.c > @@ -2284,16 +2284,20 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, > old_gov = policy->governor; > /* end old governor */ > if (old_gov) { > - __cpufreq_governor(policy, CPUFREQ_GOV_STOP); > - up_write(&policy->rwsem); > - __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); > - down_write(&policy->rwsem); > + if(!(ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP))) { > + up_write(&policy->rwsem); > + ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); > + down_write(&policy->rwsem); > + } > + > + if (ret) > + return ret; Some debug prints help here? Like "Failed to stop govenor". > } > > /* start new governor */ > policy->governor = new_policy->governor; > - if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) { > - if (!__cpufreq_governor(policy, CPUFREQ_GOV_START)) > + if (!(ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT))) { > + if (!(ret = __cpufreq_governor(policy, CPUFREQ_GOV_START))) > goto out; > > up_write(&policy->rwsem); > @@ -2305,11 +2309,11 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, > pr_debug("starting governor %s failed\n", policy->governor->name); > if (old_gov) { > policy->governor = old_gov; > - __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); > - __cpufreq_governor(policy, CPUFREQ_GOV_START); > + if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) > + __cpufreq_governor(policy, CPUFREQ_GOV_START); If INIT itself fails, we need to set policy->governor to NULL. I included this in the testing of the patchset. Regards Preeti U Murthy -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in