Re: [PATCH] cpufreq: Improve code around unlisted freq check

From: Rafael J. Wysocki
Date: Fri Oct 16 2020 - 10:21:40 EST


On Tue, Oct 13, 2020 at 7:12 AM Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
>
> The cpufreq core checks if the frequency programmed by the bootloaders
> is not listed in the freq table and programs one from the table in such
> a case. This is done only if the driver has set the
> CPUFREQ_NEED_INITIAL_FREQ_CHECK flag.
>
> Currently we print two separate messages, with almost the same content,
> and do this with a pr_warn() which may be a bit too much as the driver
> only asked us to check this as it expected this to be the case. Lower
> down the severity of the print message by switching to pr_info() instead
> and print a single message only.
>
> Reported-by: Sumit Gupta <sumitg@xxxxxxxxxx>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> ---
> drivers/cpufreq/cpufreq.c | 15 +++++++--------
> 1 file changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 2ea245a6c0c0..99864afac272 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -1461,14 +1461,13 @@ static int cpufreq_online(unsigned int cpu)
> */
> if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK)
> && has_target()) {
> + unsigned int old_freq = policy->cur;
> +
> /* Are we running at unknown frequency ? */
> - ret = cpufreq_frequency_table_get_index(policy, policy->cur);
> + ret = cpufreq_frequency_table_get_index(policy, old_freq);
> if (ret == -EINVAL) {
> - /* Warn user and fix it */
> - pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n",
> - __func__, policy->cpu, policy->cur);
> - ret = __cpufreq_driver_target(policy, policy->cur - 1,
> - CPUFREQ_RELATION_L);
> + ret = __cpufreq_driver_target(policy, old_freq - 1,
> + CPUFREQ_RELATION_L);
>
> /*
> * Reaching here after boot in a few seconds may not
> @@ -1476,8 +1475,8 @@ static int cpufreq_online(unsigned int cpu)
> * frequency for longer duration. Hence, a BUG_ON().
> */
> BUG_ON(ret);
> - pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n",
> - __func__, policy->cpu, policy->cur);
> + pr_info("%s: CPU%d: Running at unlisted initial frequency: %u KHz, changing to: %u KHz\n",
> + __func__, policy->cpu, old_freq, policy->cur);
> }
> }
>
> --

Applied as 5.10-rc material, thanks!