[RFC PATCH] mmc: move clock gating work to power efficient workqueue

From: Zoran Markovic
Date: Fri Jan 31 2014 - 18:06:24 EST


From: Shaibal Dutta <shaibal.dutta@xxxxxxxxxxxx>

Instead of binding the clock gating work to the CPU that scheduled it,
allow the scheduler to select the best CPU to handle it. This extends
idle residency times and conserves power.

This functionality is enabled when CONFIG_WQ_POWER_EFFICIENT is selected.

Cc: Chris Ball <chris@xxxxxxxxxx>
Cc: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Cc: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Simon Baatz <gmbnomis@xxxxxxxxx>
Cc: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Shaibal Dutta <shaibal.dutta@xxxxxxxxxxxx>
[zoran.markovic@xxxxxxxxxx: Rebased to latest kernel. Added commit message.
Fixed code alignment.]
Signed-off-by: Zoran Markovic <zoran.markovic@xxxxxxxxxx>
---
drivers/mmc/core/host.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 49bc403..a787f1b 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -207,8 +207,9 @@ void mmc_host_clk_release(struct mmc_host *host)
host->clk_requests--;
if (mmc_host_may_gate_card(host->card) &&
!host->clk_requests)
- schedule_delayed_work(&host->clk_gate_work,
- msecs_to_jiffies(host->clkgate_delay));
+ queue_delayed_work(system_power_efficient_wq,
+ &host->clk_gate_work,
+ msecs_to_jiffies(host->clkgate_delay));
spin_unlock_irqrestore(&host->clk_lock, flags);
}

--
1.7.9.5

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