On 09-05-18, 11:44, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <[email protected]> > > If the next_freq field of struct sugov_policy is set to UINT_MAX, > it shouldn't be used for updating the CPU frequency (this is a > special "invalid" value), but after commit b7eaf1aab9f8 (cpufreq: > schedutil: Avoid reducing frequency of busy CPUs prematurely) it > may be passed as the new frequency to sugov_update_commit() in > sugov_update_single(). > > Fix that by adding an extra check for the special UINT_MAX value > of next_freq to sugov_update_single(). > > Fixes: b7eaf1aab9f8 (cpufreq: schedutil: Avoid reducing frequency of busy > CPUs prematurely) > Reported-by: Viresh Kumar <[email protected]> > Cc: 4.12+ <[email protected]> # 4.12+ > Signed-off-by: Rafael J. Wysocki <[email protected]> > --- > kernel/sched/cpufreq_schedutil.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > Index: linux-pm/kernel/sched/cpufreq_schedutil.c > =================================================================== > --- linux-pm.orig/kernel/sched/cpufreq_schedutil.c > +++ linux-pm/kernel/sched/cpufreq_schedutil.c > @@ -305,7 +305,8 @@ static void sugov_update_single(struct u > * Do not reduce the frequency if the CPU has not been idle > * recently, as the reduction is likely to be premature then. > */ > - if (busy && next_f < sg_policy->next_freq) { > + if (busy && next_f < sg_policy->next_freq && > + sg_policy->next_freq != UINT_MAX) { > next_f = sg_policy->next_freq; > > /* Reset cached freq as next_freq has changed */
Acked-by: Viresh Kumar <[email protected]> -- viresh
