From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: Re: [PATCH] PM / OPP: Fix get sharing cpus when hotplug is used Date: Fri, 21 Jul 2017 09:44:04 +0530 Message-ID: <20170721041404.GM352@vireshk-i7> References: <20170720140237.6296-1-waldemarx.rymarkiewicz@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pf0-f169.google.com ([209.85.192.169]:34751 "EHLO mail-pf0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750727AbdGUEOH (ORCPT ); Fri, 21 Jul 2017 00:14:07 -0400 Received: by mail-pf0-f169.google.com with SMTP id q85so19511122pfq.1 for ; Thu, 20 Jul 2017 21:14:07 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20170720140237.6296-1-waldemarx.rymarkiewicz@intel.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Waldemar Rymarkiewicz Cc: linux-pm@vger.kernel.org, WaldemarRymarkiewiczwaldemar.rymarkiewicz@gmail.com, Viresh Kumar , Nishanth Menon , Stephen Boyd On 20-07-17, 16:02, Waldemar Rymarkiewicz wrote: > On systems where not all possible CPUs are available for Linux, call to > dev_pm_opp_of_get_sharing_cpus() will fail as cannot find a cpu device s/fail/we fail/ > for not present (offline) CPUs. not-present != offline. But above kind of says so. We need to only say that the CPUs aren't present yet, i.e. hotplugged out. > > Example (real use case): > 2 physical MIPS cores, 4 VPE, cpu0/2 run Linux and cpu1/3 are not available > for linux at boot up. cpufreq-dt driver + opp v2 fail to register opp_table > due to the fact there is no struct device for cpu1 (remains offline at bootup). > > More generally, this is a problem for all platforms that use cpu hotplugging. > > Iterating over cpu device nodes instead of cpu device struct solves this > problem. > > Signed-off-by: Waldemar Rymarkiewicz > --- > drivers/base/power/opp/of.c | 27 ++++++++++++++++----------- > 1 file changed, 16 insertions(+), 11 deletions(-) So, this kind of means that you are abandoning your earlier patch as that isn't required anymore? You should have marked it as V2 here and provided a changelog. > diff --git a/drivers/base/power/opp/of.c b/drivers/base/power/opp/of.c > index 57eec1c..28348d6 100644 > --- a/drivers/base/power/opp/of.c > +++ b/drivers/base/power/opp/of.c > @@ -248,15 +248,21 @@ void dev_pm_opp_of_remove_table(struct device *dev) > } > EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table); > > -/* Returns opp descriptor node for a device, caller must do of_node_put() */ > -struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev) > +/* Returns opp descriptor node for a device node, caller must do of_node_put() */ > +static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np) > { > /* > * There should be only ONE phandle present in "operating-points-v2" > * property. > */ > > - return of_parse_phandle(dev->of_node, "operating-points-v2", 0); > + return of_parse_phandle(np, "operating-points-v2", 0); > +} > + > +/* Returns opp descriptor node for a device, caller must do of_node_put() */ > +struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev) > +{ > + return _opp_of_get_opp_desc_node(dev->of_node); > } > EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node); > > @@ -572,8 +578,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table); > int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, > struct cpumask *cpumask) > { > - struct device_node *np, *tmp_np; > - struct device *tcpu_dev; > + struct device_node *np, *tmp_np, *cpu_np; > int cpu, ret = 0; > > /* Get OPP descriptor node */ > @@ -593,18 +598,18 @@ int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, > if (cpu == cpu_dev->id) > continue; > > - tcpu_dev = get_cpu_device(cpu); > - if (!tcpu_dev) { > - dev_err(cpu_dev, "%s: failed to get cpu%d device\n", > + cpu_np = of_get_cpu_node(cpu, NULL); > + if (!cpu_np) { > + dev_err(cpu_dev, "%s: failed to get cpu%d node\n", > __func__, cpu); > - ret = -ENODEV; > + ret = -ENOENT; > goto put_cpu_node; > } > > /* Get OPP descriptor node */ > - tmp_np = dev_pm_opp_of_get_opp_desc_node(tcpu_dev); > + tmp_np = _opp_of_get_opp_desc_node(cpu_np); > if (!tmp_np) { > - dev_err(tcpu_dev, "%s: Couldn't find opp node.\n", > + dev_err(cpu_dev, "%s: Couldn't find opp node.\n", > __func__); > ret = -ENOENT; > goto put_cpu_node; > -- > 2.10.1 Diff looks fine though. -- viresh