From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey Starikovskiy Subject: [PATCH 1/2] ondemand: updated tune for hardware coordination Date: Wed, 26 Jul 2006 19:31:33 +0400 Message-ID: <44C78AD5.3050802@linux.intel.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cpufreq-bounces@lists.linux.org.uk Errors-To: cpufreq-bounces+glkc-cpufreq=m.gmane.org+glkc-cpufreq=m.gmane.org@lists.linux.org.uk Content-Type: text/plain; charset="us-ascii"; format="flowed" To: cpufreq@lists.linux.org.uk cpufreq_ondemand.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) 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 Index: linux-2.6.15.1/drivers/cpufreq/cpufreq_ondemand.c =================================================================== --- linux-2.6.15.1.orig/drivers/cpufreq/cpufreq_ondemand.c 2006-07-26 15:58:58.000000000 +0400 +++ linux-2.6.15.1/drivers/cpufreq/cpufreq_ondemand.c 2006-07-26 17:38:43.000000000 +0400 @@ -305,23 +305,26 @@ { 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; dbs_check_cpu(dbs_info); - 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)