From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lan Tianyu Subject: [PATCH 2/2] Cpufreq/gov: use tick_nohz_check() to check idle micro accouting support Date: Tue, 29 Oct 2013 16:48:57 +0800 Message-ID: <1383036537-30362-2-git-send-email-tianyu.lan@intel.com> References: <1383036537-30362-1-git-send-email-tianyu.lan@intel.com> Return-path: In-Reply-To: <1383036537-30362-1-git-send-email-tianyu.lan@intel.com> Sender: cpufreq-owner@vger.kernel.org To: rjw@rjwysocki.net, viresh.kumar@linaro.org Cc: Lan Tianyu , cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org Current, od_init() uses get_cpu_idle_time_us() to check whether idle micro accouting is supported. The get_cpu_idle_time_us() returns -1 only when tick nohz is disabled. This patch is to use tick_nohz_check() directly to check nohz enable status instead of get_cpu_idle_time_us(). This can avoid unnecessary getting and putting cpu. Signed-off-by: Lan Tianyu --- drivers/cpufreq/cpufreq_ondemand.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 32f26f6..79986a9 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -485,10 +485,7 @@ static int od_init(struct dbs_data *dbs_data) return -ENOMEM; } - cpu = get_cpu(); - idle_time = get_cpu_idle_time_us(cpu, NULL); - put_cpu(); - if (idle_time != -1ULL) { + if (tick_nohz_check()) { /* Idle micro accounting is supported. Use finer thresholds */ tuners->up_threshold = MICRO_FREQUENCY_UP_THRESHOLD; /* -- 1.8.4.rc0.1.g8f6a3e5.dirty