[RFC PATCH] timekeeping: move clock sync work to power efficient workqueue

From: Zoran Markovic
Date: Fri Jan 31 2014 - 14:18:45 EST


From: Shaibal Dutta <shaibal.dutta@xxxxxxxxxx>

For better use of CPU idle time, allow the scheduler to select the CPU
on which the CMOS clock sync work would be scheduled. This improves
idle residency time and conserver power.

This functionality is enabled when CONFIG_WQ_POWER_EFFICIENT is selected.

Cc: John Stultz <john.stultz@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Shaibal Dutta <shaibal.dutta@xxxxxxxxxxxx>
[zoran.markovic@xxxxxxxxxx: Added commit message. Aligned code.]
Signed-off-by: Zoran Markovic <zoran.markovic@xxxxxxxxxx>
---
kernel/time/ntp.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index af8d1d4..419a52c 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -514,12 +514,13 @@ static void sync_cmos_clock(struct work_struct *work)
next.tv_sec++;
next.tv_nsec -= NSEC_PER_SEC;
}
- schedule_delayed_work(&sync_cmos_work, timespec_to_jiffies(&next));
+ queue_delayed_work(system_power_efficient_wq,
+ &sync_cmos_work, timespec_to_jiffies(&next));
}

void ntp_notify_cmos_timer(void)
{
- schedule_delayed_work(&sync_cmos_work, 0);
+ queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0);
}

#else
--
1.7.9.5

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