From 209887e6b974c22328487b55d0f390522b014b03 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Wed, 9 Aug 2017 10:21:46 +0530 Subject: [PATCH] cpufreq: Return 0 from ->fast_switch() on errors CPUFREQ_ENTRY_INVALID is a special symbol which is used to specify that an entry in the cpufreq table is invalid. But using it outside of the scope of the cpufreq table looks a bit incorrect. We can represent an invalid frequency by writing it as 0 instead if we need. Note that it is already done that way for the return value of the ->get() callback. Lets do the same for ->fast_switch() and not use CPUFREQ_ENTRY_INVALID outside of the scope of cpufreq table. Also update the comment over cpufreq_driver_fast_switch() to clearly mention what this returns. None of the drivers return CPUFREQ_ENTRY_INVALID as of now from ->fast_switch() callback and so we don't need to update any of those. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 7 ++++--- kernel/sched/cpufreq_schedutil.c | 2 +- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 9bf97a366029..0c728190e444 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1817,9 +1817,10 @@ EXPORT_SYMBOL(cpufreq_unregister_notifier); * twice in parallel for the same policy and that it will never be called in * parallel with either ->target() or ->target_index() for the same policy. * - * If CPUFREQ_ENTRY_INVALID is returned by the driver's ->fast_switch() - * callback to indicate an error condition, the hardware configuration must be - * preserved. + * Returns the actual frequency set for the CPU. + * + * If 0 is returned by the driver's ->fast_switch() callback to indicate an + * error condition, the hardware configuration must be preserved. */ unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, unsigned int target_freq) diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 7dbc76801f86..2ba04bb3182a 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -123,7 +123,7 @@ static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time, if (policy->fast_switch_enabled) { next_freq = cpufreq_driver_fast_switch(policy, next_freq); - if (next_freq == CPUFREQ_ENTRY_INVALID) + if (!next_freq) return; policy->cur = next_freq; -- 2.20.1