From 8e3b403954507eb74ad241dc3750443ccc9ee40a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 11 Mar 2019 12:57:25 +0100 Subject: cpufreq: intel_pstate: Fix up iowait_boost computation After commit b8bd1581aa61 ("cpufreq: intel_pstate: Rework iowait boosting to be less aggressive") the handling of the case when the SCHED_CPUFREQ_IOWAIT flag is set again after a few iterations of intel_pstate_update_util() is a bit inconsistent, because the new value of cpu->iowait_boost may be lower than ONE_EIGHTH_FP if it was set before, but has not dropped down to zero just yet. Fix that up by ensuring that the new value of cpu->iowait_boost will always be at least ONE_EIGHTH_FP then. Fixes: b8bd1581aa61 ("cpufreq: intel_pstate: Rework iowait boosting to be less aggressive") Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/cpufreq') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 002f5169d4eb..e22f0dbaebb1 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1762,7 +1762,7 @@ static void intel_pstate_update_util(struct update_util_data *data, u64 time, /* Start over if the CPU may have been idle. */ if (delta_ns > TICK_NSEC) { cpu->iowait_boost = ONE_EIGHTH_FP; - } else if (cpu->iowait_boost) { + } else if (cpu->iowait_boost >= ONE_EIGHTH_FP) { cpu->iowait_boost <<= 1; if (cpu->iowait_boost > int_tofp(1)) cpu->iowait_boost = int_tofp(1); -- cgit v1.2.3-59-g8ed1b