From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Yang, Shunyong" Subject: Re: [PATCH v2] cpufreq: cppc_cpufreq: Initialize shared cpu's perf capabilities Date: Fri, 6 Apr 2018 01:10:07 +0000 Message-ID: <1522977004.8366.11.camel@hxt-semitech.com> References: <1522833380-18438-1-git-send-email-shunyong.yang@hxt-semitech.com> <20180404103600.GJ3572@vireshk-i7> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <20180404103600.GJ3572@vireshk-i7> Content-Language: en-US Content-ID: Sender: linux-kernel-owner@vger.kernel.org To: "viresh.kumar@linaro.org" Cc: "linux-kernel@vger.kernel.org" , "Zheng, Joey" , "linux-pm@vger.kernel.org" , "rjw@rjwysocki.net" List-Id: linux-pm@vger.kernel.org Hi, Kumar, On Wed, 2018-04-04 at 16:06 +0530, Viresh Kumar wrote: > On 04-04-18, 17:16, Shunyong Yang wrote: > > > > When multiple cpus are related in one cpufreq policy, the first > > online > > cpu will be chosen by default to handle cpufreq operations. Let's > > take > > cpu0 and cpu1 as an example. > > > > When cpu0 is offline, policy->cpu will be shifted to cpu1. Cpu1's > > perf > > capabilities should be initialized. Otherwise, perf capabilities > > are 0s > > and speed change can not take effect. > > > > This patch copies perf capabilities of the first online cpu to > > other > > shared cpus when policy shared type is CPUFREQ_SHARED_TYPE_ANY. > > > > Cc: Joey Zheng > > Signed-off-by: Shunyong Yang > > --- > > > > Changes in v2: > >   -Add unlikely in cpu comparison per Kumar's comments. > >   -Fix coding style per Kumar's comments. > > > > Changes in v1: > >   -Drop RFC tag, > >      The original RFC link, > >      https://patchwork.kernel.org/patch/10299055/. > > > >      This patch solves same issue as RFC above. > > > >      Patch name is changed as code is too much different with RFC > > above. > > > >   -Remove extra init() per Viresh Kumar's comments and only handle > >    CPPC CPUFREQ_SHARED_TYPE_ANY case. > > > > --- > >  drivers/cpufreq/cppc_cpufreq.c | 15 +++++++++++++-- > >  1 file changed, 13 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/cpufreq/cppc_cpufreq.c > > b/drivers/cpufreq/cppc_cpufreq.c > > index 8f7b21a4d537..679e43b9c980 100644 > > --- a/drivers/cpufreq/cppc_cpufreq.c > > +++ b/drivers/cpufreq/cppc_cpufreq.c > > @@ -164,9 +164,20 @@ static int cppc_cpufreq_cpu_init(struct > > cpufreq_policy *policy) > >   policy->cpuinfo.transition_latency = > > cppc_get_transition_latency(cpu_num); > >   policy->shared_type = cpu->shared_type; > >   > > - if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) > > + if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) { > > + int i; > > + > >   cpumask_copy(policy->cpus, cpu->shared_cpu_map); > > - else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) { > > + > > + for_each_cpu(i, policy->cpus) { > > + if (unlikely(i == policy->cpu)) > > + continue; > > + > > + memcpy(&all_cpu_data[i]->perf_caps, > > +        &cpu->perf_caps, > > +        sizeof(cpu->perf_caps)); > I think this can be written in two lines without violating the 80 > columns rule. The memcpy() is split in three lines (the three "+"). And I rechecked it by downloading from https://patchwork.kernel.org/patch/10322305/ and apply to code. The maximum column number is 59.  And I re-run checkpatch.pl and it passed. I am not sure why it is over 80 columns in your tool.  > > > > > + } > > + } else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) > > { > >   /* Support only SW_ANY for now. */ > >   pr_debug("Unsupported CPU co-ord type\n"); > >   return -EFAULT; > Acked-by: Viresh Kumar Thanks for your ACK. Thanks. Shunyong. >