From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Tue, 2 Jan 2018 11:42:39 +0000 Subject: [PATCH v3 2/2] ARM64 / cpuidle: Use new cpuidle macro for entering retention state In-Reply-To: <1510765910-23739-3-git-send-email-pprakash@codeaurora.org> References: <1510765910-23739-1-git-send-email-pprakash@codeaurora.org> <1510765910-23739-3-git-send-email-pprakash@codeaurora.org> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 15/11/17 17:11, Prashanth Prakash wrote: > CPU_PM_CPU_IDLE_ENTER_RETENTION skips calling cpu_pm_enter() and > cpu_pm_exit(). By not calling cpu_pm functions in idle entry/exit > paths we can reduce the latency involved in entering and exiting > the low power idle state. > > On ARM64 based Qualcomm server platform we measured below overhead > for calling cpu_pm_enter and cpu_pm_exit for retention states. > > workload: stress --hdd #CPUs --hdd-bytes 32M -t 30 > Average overhead of cpu_pm_enter - 1.2us > Average overhead of cpu_pm_exit - 3.1us > > Signed-off-by: Prashanth Prakash Acked-by: Sudeep Holla -- Regards, Sudeep