[PATCH V5 5/5] fbcon: queue work on power efficient wq

[PATCH V5 5/5] fbcon: queue work on power efficient wq

[Viresh Kumar]

fbcon uses workqueues and it has no real dependency of scheduling these on the
cpu which scheduled them.

On a idle system, it is observed that and idle cpu wakes up many times just to
service this work. It would be better if we can schedule it on a cpu which the
scheduler believes to be the most appropriate one.

This patch replaces system_wq with system_power_efficient_wq.

Cc: Dave Airlie <airlied@redhat.com>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/video/console/fbcon.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 3cd6759..0cae83d 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -404,7 +404,7 @@ static void cursor_timer_handler(unsigned long dev_addr)
 	struct fb_info *info = (struct fb_info *) dev_addr;
 	struct fbcon_ops *ops = info->fbcon_par;
 
-	schedule_work(&info->queue);
+	queue_work(system_power_efficient_wq, &info->queue);
 	mod_timer(&ops->cursor_timer, jiffies + HZ/5);
 }
 
-- 
1.7.12.rc2.18.g61b472e

Re: [PATCH V5 5/5] fbcon: queue work on power efficient wq

[Tejun Heo]

On Wed, Apr 24, 2013 at 05:12:57PM +0530, Viresh Kumar wrote:
> fbcon uses workqueues and it has no real dependency of scheduling these on the
> cpu which scheduled them.
> 
> On a idle system, it is observed that and idle cpu wakes up many times just to
> service this work. It would be better if we can schedule it on a cpu which the
> scheduler believes to be the most appropriate one.
> 
> This patch replaces system_wq with system_power_efficient_wq.
> 
> Cc: Dave Airlie <airlied@redhat.com>
> Cc: linux-fbdev@vger.kernel.org
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Dave, applied this to wq/for-3.11.  Please holler if you want this to
be routed differently.

Thanks!

-- 
tejun