From 43b68879de27b1993518687fbc6013da80cdcbfe Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Thu, 26 Feb 2015 18:20:48 +0100 Subject: [PATCH 1/2] cpuidle: mvebu: Fix the CPU PM notifier usage As stated in kernel/cpu_pm.c, "Platform is responsible for ensuring that cpu_pm_enter is not called twice on the same CPU before cpu_pm_exit is called.". In the current code in case of failure when calling mvebu_v7_cpu_suspend, the function cpu_pm_exit() is never called whereas cpu_pm_enter() was called just before. This patch moves the cpu_pm_exit() in order to balance the cpu_pm_enter() calls. Cc: stable@vger.kernel.org Reported-by: Fulvio Benini Signed-off-by: Gregory CLEMENT Signed-off-by: Daniel Lezcano --- drivers/cpuidle/cpuidle-mvebu-v7.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/cpuidle/cpuidle-mvebu-v7.c b/drivers/cpuidle/cpuidle-mvebu-v7.c index 38e68618513a..cefa07438ae1 100644 --- a/drivers/cpuidle/cpuidle-mvebu-v7.c +++ b/drivers/cpuidle/cpuidle-mvebu-v7.c @@ -37,11 +37,11 @@ static int mvebu_v7_enter_idle(struct cpuidle_device *dev, deepidle = true; ret = mvebu_v7_cpu_suspend(deepidle); + cpu_pm_exit(); + if (ret) return ret; - cpu_pm_exit(); - return index; } From ce6031c89a35cffd5a5992b08377b77f49a004b9 Mon Sep 17 00:00:00 2001 From: Sebastien Rannou Date: Fri, 13 Feb 2015 15:55:03 +0100 Subject: [PATCH 2/2] cpuidle: mvebu: Update cpuidle thresholds for Armada XP SOCs Originally, the thresholds used in the cpuidle driver for Armada SOCs were temporarily chosen, leaving room for improvements. This commit updates the thresholds for the Armada XP SOCs with values that positively impact performances: without patch with patch vendor kernel - iperf localhost (gbit/sec) ~3.7 ~6.4 ~5.4 - ioping tmpfs (iops) ~163k ~206k ~179k - ioping tmpfs (mib/s) ~636 ~805 ~699 The idle power consumption is negatively impacted (proportionally less than the performance gain), and we are still performing better than the vendor kernel here: without patch with patch vendor kernel - power consumption idle (W) ~2.4 ~3.2 ~4.4 - power consumption busy (W) ~8.6 ~8.3 ~8.6 There is still room for improvement regarding the value of these thresholds, they were chosen to mimic the vendor kernel. This patch only impacts Armada XP SOCs and was tested on Online Labs C1 boards. A similar approach can be taken to improve the performances of the Armada 370 and Armada 38x SOCs. Thanks a lot to Thomas Petazzoni, Gregory Clement and Willy Tarreau for the discussions and tips around this topic. Signed-off-by: Sebastien Rannou Signed-off-by: Daniel Lezcano Acked-by: Gregory CLEMENT --- drivers/cpuidle/cpuidle-mvebu-v7.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/cpuidle/cpuidle-mvebu-v7.c b/drivers/cpuidle/cpuidle-mvebu-v7.c index cefa07438ae1..980151f34707 100644 --- a/drivers/cpuidle/cpuidle-mvebu-v7.c +++ b/drivers/cpuidle/cpuidle-mvebu-v7.c @@ -50,17 +50,17 @@ static struct cpuidle_driver armadaxp_idle_driver = { .states[0] = ARM_CPUIDLE_WFI_STATE, .states[1] = { .enter = mvebu_v7_enter_idle, - .exit_latency = 10, + .exit_latency = 100, .power_usage = 50, - .target_residency = 100, + .target_residency = 1000, .name = "MV CPU IDLE", .desc = "CPU power down", }, .states[2] = { .enter = mvebu_v7_enter_idle, - .exit_latency = 100, + .exit_latency = 1000, .power_usage = 5, - .target_residency = 1000, + .target_residency = 10000, .flags = MVEBU_V7_FLAG_DEEP_IDLE, .name = "MV CPU DEEP IDLE", .desc = "CPU and L2 Fabric power down",