67 lines
2.5 KiB
Diff
67 lines
2.5 KiB
Diff
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From ce6031c89a35cffd5a5992b08377b77f49a004b9 Mon Sep 17 00:00:00 2001
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From: Sebastien Rannou <mxs@sbrk.org>
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Date: Fri, 13 Feb 2015 15:55:03 +0100
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Subject: [PATCH] cpuidle: mvebu: Update cpuidle thresholds for Armada XP SOCs
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Originally, the thresholds used in the cpuidle driver for Armada SOCs
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were temporarily chosen, leaving room for improvements.
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This commit updates the thresholds for the Armada XP SOCs with values
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that positively impact performances:
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without patch with patch vendor kernel
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- iperf localhost (gbit/sec) ~3.7 ~6.4 ~5.4
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- ioping tmpfs (iops) ~163k ~206k ~179k
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- ioping tmpfs (mib/s) ~636 ~805 ~699
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The idle power consumption is negatively impacted (proportionally less
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than the performance gain), and we are still performing better than
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the vendor kernel here:
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without patch with patch vendor kernel
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- power consumption idle (W) ~2.4 ~3.2 ~4.4
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- power consumption busy (W) ~8.6 ~8.3 ~8.6
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There is still room for improvement regarding the value of these
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thresholds, they were chosen to mimic the vendor kernel.
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This patch only impacts Armada XP SOCs and was tested on Online Labs
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C1 boards. A similar approach can be taken to improve the performances
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of the Armada 370 and Armada 38x SOCs.
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Thanks a lot to Thomas Petazzoni, Gregory Clement and Willy Tarreau
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for the discussions and tips around this topic.
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Signed-off-by: Sebastien Rannou <mxs@sbrk.org>
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Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
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Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
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---
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drivers/cpuidle/cpuidle-mvebu-v7.c | 8 ++++----
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1 file changed, 4 insertions(+), 4 deletions(-)
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--- a/drivers/cpuidle/cpuidle-mvebu-v7.c
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+++ b/drivers/cpuidle/cpuidle-mvebu-v7.c
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@@ -50,18 +50,18 @@ static struct cpuidle_driver armadaxp_id
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.states[0] = ARM_CPUIDLE_WFI_STATE,
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.states[1] = {
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.enter = mvebu_v7_enter_idle,
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- .exit_latency = 10,
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+ .exit_latency = 100,
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.power_usage = 50,
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- .target_residency = 100,
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+ .target_residency = 1000,
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.flags = CPUIDLE_FLAG_TIME_VALID,
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.name = "MV CPU IDLE",
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.desc = "CPU power down",
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},
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.states[2] = {
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.enter = mvebu_v7_enter_idle,
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- .exit_latency = 100,
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+ .exit_latency = 1000,
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.power_usage = 5,
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- .target_residency = 1000,
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+ .target_residency = 10000,
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.flags = CPUIDLE_FLAG_TIME_VALID |
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MVEBU_V7_FLAG_DEEP_IDLE,
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.name = "MV CPU DEEP IDLE",
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