| Message ID | 20230912060957.2516790-1-liaochang1@huawei.com |
|---|---|
| State | New |
| Headers | show |
| Series | cpufreq: conservative: Ensure requested_freq is greater than min frequency | expand |
On 12-09-23, 06:09, Liao Chang wrote: > The governor ensures that the requested frequency is greater than the > minimum frequency when the condition for decreasing frequency is > satisfied. This is done by either reducing the frequency step from the > current frequency if the current frequency is greater than the sum of > the frequency step and the minimum frequency, or setting the frequency > to the minimum one otherwise. > > Signed-off-by: Liao Chang <liaochang1@huawei.com> > --- > drivers/cpufreq/cpufreq_conservative.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c > index 56500b25d77c..54e09242b2e2 100644 > --- a/drivers/cpufreq/cpufreq_conservative.c > +++ b/drivers/cpufreq/cpufreq_conservative.c > @@ -130,7 +130,7 @@ static unsigned int cs_dbs_update(struct cpufreq_policy *policy) > 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; I think all we want to ensure here is that we don't end up getting a negative number (since requested_freq is unsigned int, it will end up being a very large freq). __cpufreq_driver_target() will eventually set the freq to policy->min only as we are using CPUFREQ_RELATION_LE here.
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 56500b25d77c..54e09242b2e2 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -130,7 +130,7 @@ static unsigned int cs_dbs_update(struct cpufreq_policy *policy) 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;
The governor ensures that the requested frequency is greater than the minimum frequency when the condition for decreasing frequency is satisfied. This is done by either reducing the frequency step from the current frequency if the current frequency is greater than the sum of the frequency step and the minimum frequency, or setting the frequency to the minimum one otherwise. Signed-off-by: Liao Chang <liaochang1@huawei.com> --- drivers/cpufreq/cpufreq_conservative.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)