Kernel/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-01-01 10:43:43 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

cpufreq_schedutil: Refactor sugov_cpu_is_busy()

Browse Source 
sugov_cpu_is_busy() is used to avoid decreasing performance level while the
CPU is busy and called by sugov_update_single_freq() and
sugov_update_single_perf(). Both callers repeat the same pattern to first
test for uclamp and then the business. Let's refactor so that the tests
aren't repeated.

The new helper is named sugov_hold_freq() and tests both the uclamp
exception and CPU business. No functional changes. This will make adding
more exception conditions easier.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Vernet <dvernet@meta.com>
Reviewed-by: Christian Loehle <christian.loehle@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
This commit is contained in:
Tejun Heo 2024-06-21 12:37:03 -10:00
parent b999e365c2
commit 8988cad8d0
1 changed files with 18 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
kernel/sched/cpufreq_schedutil.c
View File

@ -325,16 +325,27 @@ static unsigned long sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
}
#ifdef CONFIG_NO_HZ_COMMON
static bool sugov_cpu_is_busy(struct sugov_cpu *sg_cpu)
static bool sugov_hold_freq(struct sugov_cpu *sg_cpu)
{
unsigned long idle_calls = tick_nohz_get_idle_calls_cpu(sg_cpu->cpu);
bool ret = idle_calls == sg_cpu->saved_idle_calls;
unsigned long idle_calls;
bool ret;
/* if capped by uclamp_max, always update to be in compliance */
if (uclamp_rq_is_capped(cpu_rq(sg_cpu->cpu)))
return false;
/*
* Maintain the frequency if the CPU has not been idle recently, as
* reduction is likely to be premature.
*/
idle_calls = tick_nohz_get_idle_calls_cpu(sg_cpu->cpu);
ret = idle_calls == sg_cpu->saved_idle_calls;
sg_cpu->saved_idle_calls = idle_calls;
return ret;
}
#else
static inline bool sugov_cpu_is_busy(struct sugov_cpu *sg_cpu) { return false; }
static inline bool sugov_hold_freq(struct sugov_cpu *sg_cpu) { return false; }
#endif /* CONFIG_NO_HZ_COMMON */
/*
@ -382,14 +393,8 @@ static void sugov_update_single_freq(struct update_util_data *hook, u64 time,
return;
next_f = get_next_freq(sg_policy, sg_cpu->util, max_cap);
/*
* Do not reduce the frequency if the CPU has not been idle
* recently, as the reduction is likely to be premature then.
*
* Except when the rq is capped by uclamp_max.
*/
if (!uclamp_rq_is_capped(cpu_rq(sg_cpu->cpu)) &&
sugov_cpu_is_busy(sg_cpu) && next_f < sg_policy->next_freq &&
if (sugov_hold_freq(sg_cpu) && next_f < sg_policy->next_freq &&
!sg_policy->need_freq_update) {
next_f = sg_policy->next_freq;
@ -436,14 +441,7 @@ static void sugov_update_single_perf(struct update_util_data *hook, u64 time,
if (!sugov_update_single_common(sg_cpu, time, max_cap, flags))
return;
/*
* Do not reduce the target performance level if the CPU has not been
* idle recently, as the reduction is likely to be premature then.
*
* Except when the rq is capped by uclamp_max.
*/
if (!uclamp_rq_is_capped(cpu_rq(sg_cpu->cpu)) &&
sugov_cpu_is_busy(sg_cpu) && sg_cpu->util < prev_util)
if (sugov_hold_freq(sg_cpu) && sg_cpu->util < prev_util)
sg_cpu->util = prev_util;
cpufreq_driver_adjust_perf(sg_cpu->cpu, sg_cpu->bw_min,