linux-kernel - Re: [PATCH 0/2] cpufreq/opp: rework regulator initialization

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190211084714.nq3wqxk66dbrfqvy@vireshk-i7>
Date:   Mon, 11 Feb 2019 14:17:14 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Sudeep Holla <sudeep.holla@....com>
Cc:     Marek Szyprowski <m.szyprowski@...sung.com>,
        linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        linux-samsung-soc@...r.kernel.org,
        "Rafael J . Wysocki" <rjw@...ysocki.net>,
        Nishanth Menon <nm@...com>, Stephen Boyd <sboyd@...nel.org>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
        Dave Gerlach <d-gerlach@...com>,
        Wolfram Sang <wsa@...-dreams.de>
Subject: Re: [PATCH 0/2] cpufreq/opp: rework regulator initialization

On 08-02-19, 17:41, Sudeep Holla wrote:
> Based on Rafael's suggestion, I cooked up something. See if this helps ?
> The policy to cpu dance can be removed and we can just run through the
> online cpumask I think.
> 
> Regards,
> Sudeep
> 
> -->8
> 
> diff --git i/drivers/cpufreq/cpufreq.c w/drivers/cpufreq/cpufreq.c
> index e35a886e00bc..03d65a02a542 100644
> --- i/drivers/cpufreq/cpufreq.c
> +++ w/drivers/cpufreq/cpufreq.c
> @@ -1640,6 +1640,7 @@ EXPORT_SYMBOL(cpufreq_generic_suspend);
>  void cpufreq_suspend(void)
>  {
>  	struct cpufreq_policy *policy;
> +	int cpu;
>  
>  	if (!cpufreq_driver)
>  		return;
> @@ -1662,6 +1663,11 @@ void cpufreq_suspend(void)
>  	}
>  
>  suspend:
> +	if (cpufreq_driver->flags & CPUFREQ_DEFER_INIT_DURING_RESUME)
> +		for_each_active_policy(policy)
> +			for_each_cpu(cpu, policy->cpus)
> +				cpufreq_offline(cpu);

You will offline boot-cpu as well :)

> +
>  	cpufreq_suspended = true;
>  }
>  
> @@ -1674,7 +1680,7 @@ void cpufreq_suspend(void)
>  void cpufreq_resume(void)
>  {
>  	struct cpufreq_policy *policy;
> -	int ret;
> +	int ret, cpu;
>  
>  	if (!cpufreq_driver)
>  		return;
> @@ -1682,6 +1688,11 @@ void cpufreq_resume(void)
>  	if (unlikely(!cpufreq_suspended))
>  		return;
>  
> +	if (cpufreq_driver->flags & CPUFREQ_DEFER_INIT_DURING_RESUME)
> +		for_each_active_policy(policy)
> +			for_each_cpu(cpu, policy->cpus)
> +				cpufreq_online(cpu);
> +
>  	cpufreq_suspended = false;
>  
>  	if (!has_target() && !cpufreq_driver->resume)
> @@ -2444,14 +2455,16 @@ static enum cpuhp_state hp_online;
>  
>  static int cpuhp_cpufreq_online(unsigned int cpu)
>  {
> -	cpufreq_online(cpu);
> +	if (!(cpufreq_driver->flags & CPUFREQ_DEFER_INIT_DURING_RESUME))
> +		cpufreq_online(cpu);

This isn't correct as we can offline the CPUs without suspend as well
and cpufreq_online/offline should always be called in such cases.

Anyways, I have cc'd you on another series which may end up fixing
this problem as well.

-- 
viresh