From: Qais Yousef qais.yousef@arm.com
[ Upstream commit d37aee9018e68b0d356195caefbb651910e0bbfa ]
iowait_boost signal is applied independently of util and doesn't take into account uclamp settings of the rq. An io heavy task that is capped by uclamp_max could still request higher frequency because sugov_iowait_apply() doesn't clamp the boost via uclamp_rq_util_with() like effective_cpu_util() does.
Make sure that iowait_boost honours uclamp requests by calling uclamp_rq_util_with() when applying the boost.
Fixes: 982d9cdc22c9 ("sched/cpufreq, sched/uclamp: Add clamps for FAIR and RT tasks") Signed-off-by: Qais Yousef qais.yousef@arm.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Acked-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Link: https://lore.kernel.org/r/20211216225320.2957053-3-qais.yousef@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/sched/cpufreq_schedutil.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index e7af18857371..7f6bb37d3a2f 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -289,6 +289,7 @@ static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time) * into the same scale so we can compare. */ boost = (sg_cpu->iowait_boost * sg_cpu->max) >> SCHED_CAPACITY_SHIFT; + boost = uclamp_rq_util_with(cpu_rq(sg_cpu->cpu), boost, NULL); if (sg_cpu->util < boost) sg_cpu->util = boost; }