From 1ce28d6b19112a7c76af8e971e2de3109d19a943 Mon Sep 17 00:00:00 2001 From: Alexey Starikovskiy Date: Mon, 31 Jul 2006 22:25:20 +0400 Subject: [CPUFREQ][1/2] ondemand: updated tune for hardware coordination Try to make dbs_check_cpu() call on all CPUs at the same jiffy. This will help when multiple cores share P-states via Hardware Coordination. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Alexey Starikovskiy Signed-off-by: Dave Jones --- drivers/cpufreq/cpufreq_ondemand.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 52cf1f02182..f507a869acb 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -305,6 +305,9 @@ static void do_dbs_timer(void *data) { unsigned int cpu = smp_processor_id(); struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu); + /* We want all CPUs to do sampling nearly on same jiffy */ + int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); + delay -= jiffies % delay; if (!dbs_info->enable) return; @@ -312,18 +315,18 @@ static void do_dbs_timer(void *data) lock_cpu_hotplug(); dbs_check_cpu(dbs_info); unlock_cpu_hotplug(); - queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, - usecs_to_jiffies(dbs_tuners_ins.sampling_rate)); + queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay); } static inline void dbs_timer_init(unsigned int cpu) { struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu); + /* We want all CPUs to do sampling nearly on same jiffy */ + int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); + delay -= jiffies % delay; INIT_WORK(&dbs_info->work, do_dbs_timer, 0); - queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, - usecs_to_jiffies(dbs_tuners_ins.sampling_rate)); - return; + queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay); } static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info) -- cgit v1.2.3-70-g09d2