| Message ID | 20230418113459.12860-2-sumitg@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | CPPC_CPUFREQ improvements for Tegra241 | expand |
On Tue, Apr 18, 2023 at 1:35 PM Sumit Gupta <sumitg@nvidia.com> wrote: > > From: Sanjay Chandrashekara <sanjayc@nvidia.com> > > cpufreq_verify_current_freq checks if the frequency returned by > the hardware has a slight delta with the valid frequency value > last set and returns "policy->cur" if the delta is within "1 MHz". > In the comparison, "policy->cur" is in "kHz" but it's compared > against HZ_PER_MHZ. So, the comparison range becomes "1 GHz". > Fix this by comparing against KHZ_PER_MHZ instead of HZ_PER_MHZ. > > Fixes: f55ae08c8987 ("cpufreq: Avoid unnecessary frequency updates due to mismatch") > Signed-off-by: Sanjay Chandrashekara <sanjayc@nvidia.com> > [ sumit gupta: Commit message update ] > Signed-off-by: Sumit Gupta <sumitg@nvidia.com> > --- > drivers/cpufreq/cpufreq.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > index 8b0509f89f1b..6b52ebe5a890 100644 > --- a/drivers/cpufreq/cpufreq.c > +++ b/drivers/cpufreq/cpufreq.c > @@ -1732,7 +1732,7 @@ static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, b > * MHz. In such cases it is better to avoid getting into > * unnecessary frequency updates. > */ > - if (abs(policy->cur - new_freq) < HZ_PER_MHZ) > + if (abs(policy->cur - new_freq) < KHZ_PER_MHZ) > return policy->cur; > > cpufreq_out_of_sync(policy, new_freq); > -- So this is a fix that can be applied separately from the rest of the series, isn't it?
On 18/04/23 18:27, Rafael J. Wysocki wrote: > External email: Use caution opening links or attachments > > > On Tue, Apr 18, 2023 at 1:35 PM Sumit Gupta <sumitg@nvidia.com> wrote: >> >> From: Sanjay Chandrashekara <sanjayc@nvidia.com> >> >> cpufreq_verify_current_freq checks if the frequency returned by >> the hardware has a slight delta with the valid frequency value >> last set and returns "policy->cur" if the delta is within "1 MHz". >> In the comparison, "policy->cur" is in "kHz" but it's compared >> against HZ_PER_MHZ. So, the comparison range becomes "1 GHz". >> Fix this by comparing against KHZ_PER_MHZ instead of HZ_PER_MHZ. >> >> Fixes: f55ae08c8987 ("cpufreq: Avoid unnecessary frequency updates due to mismatch") >> Signed-off-by: Sanjay Chandrashekara <sanjayc@nvidia.com> >> [ sumit gupta: Commit message update ] >> Signed-off-by: Sumit Gupta <sumitg@nvidia.com> >> --- >> drivers/cpufreq/cpufreq.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c >> index 8b0509f89f1b..6b52ebe5a890 100644 >> --- a/drivers/cpufreq/cpufreq.c >> +++ b/drivers/cpufreq/cpufreq.c >> @@ -1732,7 +1732,7 @@ static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, b >> * MHz. In such cases it is better to avoid getting into >> * unnecessary frequency updates. >> */ >> - if (abs(policy->cur - new_freq) < HZ_PER_MHZ) >> + if (abs(policy->cur - new_freq) < KHZ_PER_MHZ) >> return policy->cur; >> >> cpufreq_out_of_sync(policy, new_freq); >> -- > > So this is a fix that can be applied separately from the rest of the > series, isn't it? Yes. Thank you, Sumit Gupta
On Tue, Apr 18, 2023 at 3:32 PM Sumit Gupta <sumitg@nvidia.com> wrote: > > > > On 18/04/23 18:27, Rafael J. Wysocki wrote: > > External email: Use caution opening links or attachments > > > > > > On Tue, Apr 18, 2023 at 1:35 PM Sumit Gupta <sumitg@nvidia.com> wrote: > >> > >> From: Sanjay Chandrashekara <sanjayc@nvidia.com> > >> > >> cpufreq_verify_current_freq checks if the frequency returned by > >> the hardware has a slight delta with the valid frequency value > >> last set and returns "policy->cur" if the delta is within "1 MHz". > >> In the comparison, "policy->cur" is in "kHz" but it's compared > >> against HZ_PER_MHZ. So, the comparison range becomes "1 GHz". > >> Fix this by comparing against KHZ_PER_MHZ instead of HZ_PER_MHZ. > >> > >> Fixes: f55ae08c8987 ("cpufreq: Avoid unnecessary frequency updates due to mismatch") > >> Signed-off-by: Sanjay Chandrashekara <sanjayc@nvidia.com> > >> [ sumit gupta: Commit message update ] > >> Signed-off-by: Sumit Gupta <sumitg@nvidia.com> > >> --- > >> drivers/cpufreq/cpufreq.c | 2 +- > >> 1 file changed, 1 insertion(+), 1 deletion(-) > >> > >> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > >> index 8b0509f89f1b..6b52ebe5a890 100644 > >> --- a/drivers/cpufreq/cpufreq.c > >> +++ b/drivers/cpufreq/cpufreq.c > >> @@ -1732,7 +1732,7 @@ static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, b > >> * MHz. In such cases it is better to avoid getting into > >> * unnecessary frequency updates. > >> */ > >> - if (abs(policy->cur - new_freq) < HZ_PER_MHZ) > >> + if (abs(policy->cur - new_freq) < KHZ_PER_MHZ) > >> return policy->cur; > >> > >> cpufreq_out_of_sync(policy, new_freq); > >> -- > > > > So this is a fix that can be applied separately from the rest of the > > series, isn't it? > > Yes. So applied as 6.4 material.
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 8b0509f89f1b..6b52ebe5a890 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1732,7 +1732,7 @@ static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, b * MHz. In such cases it is better to avoid getting into * unnecessary frequency updates. */ - if (abs(policy->cur - new_freq) < HZ_PER_MHZ) + if (abs(policy->cur - new_freq) < KHZ_PER_MHZ) return policy->cur; cpufreq_out_of_sync(policy, new_freq);