mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com>
To: Viresh Kumar <viresh.kumar@linaro.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Stratos Karafotis <stratosk@semaphore.gr>
Cc: linux-pm@vger.kernel.org,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Sumit Semwal <sumit.semwal@linaro.org>,
	Lifeng Zheng <zhenglifeng1@huawei.com>,
	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
	linux-kernel@vger.kernel.org, zhongqiu.han@oss.qualcomm.com
Subject: Re: [PATCH V2 3/3] cpufreq: conservative: Simplify frequency limit handling
Date: Fri, 22 May 2026 13:40:21 +0800	[thread overview]
Message-ID: <73d4fac8-9b49-4872-807f-8a69219aee7a@oss.qualcomm.com> (raw)
In-Reply-To: <292e6d937890f135e30ec0d2107eaad47cb9a976.1779423281.git.viresh.kumar@linaro.org>

On 5/22/2026 12:19 PM, Viresh Kumar wrote:
> From: Lifeng Zheng <zhenglifeng1@huawei.com>
> 
> cs_dbs_update() performs explicit checks against policy->min/max
> before updating the target frequency. These checks are redundant as
> __cpufreq_driver_target() already clamps the requested frequency to
> the valid policy limits.
> 
> Remove the unnecessary boundary checks and simplify the update logic.
> 
> This also fixes an issue introduced by commit 00bfe05889e9 ("cpufreq:
> conservative: Decrease frequency faster for deferred updates"), where
> stale target comparisons could cause frequency updates to be skipped
> entirely after deferred adjustments.
> 
> Closes: https://lore.kernel.org/all/20260421123545.1745998-1-zhenglifeng1@huawei.com/
> Fixes: 00bfe05889e9 ("cpufreq: conservative: Decrease frequency faster for deferred updates")
> Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
> Co-developed-by: Viresh Kumar <viresh.kumar@linaro.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>


Thanks Viresh and Lifeng, this looks good to me.

Reviewed-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com>


> ---
>   drivers/cpufreq/cpufreq_conservative.c | 12 +-----------
>   1 file changed, 1 insertion(+), 11 deletions(-)
> 
> diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
> index df01d33993d8..0b32ae28ec85 100644
> --- a/drivers/cpufreq/cpufreq_conservative.c
> +++ b/drivers/cpufreq/cpufreq_conservative.c
> @@ -103,10 +103,6 @@ static unsigned int cs_dbs_update(struct cpufreq_policy *policy)
>   	if (load > dbs_data->up_threshold) {
>   		dbs_info->down_skip = 0;
>   
> -		/* if we are already at full speed then break out early */
> -		if (requested_freq == policy->max)
> -			goto out;
> -
>   		requested_freq += freq_step;
>   		if (requested_freq > policy->max)
>   			requested_freq = policy->max;
> @@ -124,13 +120,7 @@ static unsigned int cs_dbs_update(struct cpufreq_policy *policy)
>   
>   	/* Check for frequency decrease */
>   	if (load < cs_tuners->down_threshold) {
> -		/*
> -		 * if we cannot reduce the frequency anymore, break out early
> -		 */
> -		if (requested_freq == policy->min)
> -			goto out;
> -
> -		if (requested_freq > freq_step)
> +		if (requested_freq > policy->min + freq_step)
>   			requested_freq -= freq_step;
>   		else
>   			requested_freq = policy->min;


-- 
Thx and BRs,
Zhongqiu Han

  reply	other threads:[~2026-05-22  5:40 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-22  4:19 [PATCH V2 0/3] cpufreq: Simplify freq " Viresh Kumar
2026-05-22  4:19 ` [PATCH V2 1/3] cpufreq: Fix typo in comment Viresh Kumar
2026-05-22  4:19 ` [PATCH V3 2/3] cpufreq: Avoid redundant target() calls for unchanged limits Viresh Kumar
2026-05-22  5:39   ` Zhongqiu Han
2026-05-22  4:19 ` [PATCH V2 3/3] cpufreq: conservative: Simplify frequency limit handling Viresh Kumar
2026-05-22  5:40   ` Zhongqiu Han [this message]
2026-05-22 16:43 ` [PATCH V2 0/3] cpufreq: Simplify freq " Rafael J. Wysocki
2026-05-25 15:49   ` Rafael J. Wysocki
  -- strict thread matches above, loose matches on Subject: below --
2026-05-21 11:39 [PATCH 1/3] cpufreq: Fix typo in comment Viresh Kumar
2026-05-21 11:39 ` [PATCH V2 3/3] cpufreq: conservative: Simplify frequency limit handling Viresh Kumar

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=73d4fac8-9b49-4872-807f-8a69219aee7a@oss.qualcomm.com \
    --to=zhongqiu.han@oss.qualcomm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=rafael.j.wysocki@intel.com \
    --cc=rafael@kernel.org \
    --cc=stratosk@semaphore.gr \
    --cc=sumit.semwal@linaro.org \
    --cc=vincent.guittot@linaro.org \
    --cc=viresh.kumar@linaro.org \
    --cc=zhenglifeng1@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome