| Message ID | 1476220320-19685-1-git-send-email-hotran@apm.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tuesday, October 11, 2016 02:12:00 PM Hoan Tran wrote: > The desired_perf is an abstract performance number. Its value should > be in the range of [lowest perf, highest perf] of CPPC. > The correct calculation is > desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz > > Signed-off-by: Hoan Tran <hotran@apm.com> > --- > drivers/cpufreq/cppc_cpufreq.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c > index 1b2f28f..ab1d4b7 100644 > --- a/drivers/cpufreq/cppc_cpufreq.c > +++ b/drivers/cpufreq/cppc_cpufreq.c > @@ -84,7 +84,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, > > cpu = all_cpu_data[policy->cpu]; > > - cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; > + cpu->perf_ctrls.desired_perf = (u64)target_freq * cpu->perf_caps.highest_perf / cppc_dmi_max_khz; > freqs.old = policy->cur; > freqs.new = target_freq; > > This patch has already been applied AFAICS. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Rafael, On Tue, Oct 11, 2016 at 2:50 PM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > On Tuesday, October 11, 2016 02:12:00 PM Hoan Tran wrote: >> The desired_perf is an abstract performance number. Its value should >> be in the range of [lowest perf, highest perf] of CPPC. >> The correct calculation is >> desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz >> >> Signed-off-by: Hoan Tran <hotran@apm.com> >> --- >> drivers/cpufreq/cppc_cpufreq.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c >> index 1b2f28f..ab1d4b7 100644 >> --- a/drivers/cpufreq/cppc_cpufreq.c >> +++ b/drivers/cpufreq/cppc_cpufreq.c >> @@ -84,7 +84,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, >> >> cpu = all_cpu_data[policy->cpu]; >> >> - cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; >> + cpu->perf_ctrls.desired_perf = (u64)target_freq * cpu->perf_caps.highest_perf / cppc_dmi_max_khz; >> freqs.old = policy->cur; >> freqs.new = target_freq; >> >> > > This patch has already been applied AFAICS. > You mean this applied patch "cpufreq: CPPC: Avoid overflow when calculating desired_perf" This is another the bug, not the overflow bug. Thanks Hoan > Thanks, > Rafael > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 11-10-16, 14:12, Hoan Tran wrote: > The desired_perf is an abstract performance number. Its value should > be in the range of [lowest perf, highest perf] of CPPC. > The correct calculation is > desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz > > Signed-off-by: Hoan Tran <hotran@apm.com> > --- > drivers/cpufreq/cppc_cpufreq.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c > index 1b2f28f..ab1d4b7 100644 > --- a/drivers/cpufreq/cppc_cpufreq.c > +++ b/drivers/cpufreq/cppc_cpufreq.c > @@ -84,7 +84,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, > > cpu = all_cpu_data[policy->cpu]; > > - cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; > + cpu->perf_ctrls.desired_perf = (u64)target_freq * cpu->perf_caps.highest_perf / cppc_dmi_max_khz; > freqs.old = policy->cur; > freqs.new = target_freq; I am not sure what the calculations should be like, but I don't have any objections against applying this.. Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Hi Hoan, On 10/11/2016 3:12 PM, Hoan Tran wrote: > The desired_perf is an abstract performance number. Its value should > be in the range of [lowest perf, highest perf] of CPPC. > The correct calculation is > desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz > > Signed-off-by: Hoan Tran <hotran@apm.com> > --- > drivers/cpufreq/cppc_cpufreq.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c > index 1b2f28f..ab1d4b7 100644 > --- a/drivers/cpufreq/cppc_cpufreq.c > +++ b/drivers/cpufreq/cppc_cpufreq.c > @@ -84,7 +84,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, > > cpu = all_cpu_data[policy->cpu]; > > - cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; > + cpu->perf_ctrls.desired_perf = (u64)target_freq * cpu->perf_caps.highest_perf / cppc_dmi_max_khz; The patch looks good, I suppose we can add a small optimization. We can do a simple check to see if the newly computed desired_perf is same as old one, If it is same we can just return here instead of calling cppc_set_perf with same desired_perf value. Thanks, Prashanth -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[Resend with plain text mode] Hi Prashanth, On Wed, Oct 12, 2016 at 8:36 AM, Prakash, Prashanth <pprakash@codeaurora.org> wrote: > Hi Hoan, > > On 10/11/2016 3:12 PM, Hoan Tran wrote: >> The desired_perf is an abstract performance number. Its value should >> be in the range of [lowest perf, highest perf] of CPPC. >> The correct calculation is >> desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz >> >> Signed-off-by: Hoan Tran <hotran@apm.com> >> --- >> drivers/cpufreq/cppc_cpufreq.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c >> index 1b2f28f..ab1d4b7 100644 >> --- a/drivers/cpufreq/cppc_cpufreq.c >> +++ b/drivers/cpufreq/cppc_cpufreq.c >> @@ -84,7 +84,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, >> >> cpu = all_cpu_data[policy->cpu]; >> >> - cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; >> + cpu->perf_ctrls.desired_perf = (u64)target_freq * cpu->perf_caps.highest_perf / cppc_dmi_max_khz; > The patch looks good, I suppose we can add a small optimization. We can do a simple check > to see if the newly computed desired_perf is same as old one, If it is same we can just return > here instead of calling cppc_set_perf with same desired_perf value. That's a good point. I can add a check into this patch. Thanks Hoan > > Thanks, > Prashanth -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 1b2f28f..ab1d4b7 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -84,7 +84,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, cpu = all_cpu_data[policy->cpu]; - cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; + cpu->perf_ctrls.desired_perf = (u64)target_freq * cpu->perf_caps.highest_perf / cppc_dmi_max_khz; freqs.old = policy->cur; freqs.new = target_freq;
The desired_perf is an abstract performance number. Its value should be in the range of [lowest perf, highest perf] of CPPC. The correct calculation is desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz Signed-off-by: Hoan Tran <hotran@apm.com> --- drivers/cpufreq/cppc_cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)