[patch 0/7] tick: Optimize broadcast handling and prevent expiry ping pong

Santosh Shilimkar santosh.shilimkar at ti.com
Wed Mar 13 05:35:16 EDT 2013


Thomas,

On Wednesday 06 March 2013 04:48 PM, Thomas Gleixner wrote:
> Jason decoded a problem related to the broadcast timer mode. The
> reprogramming of the cpu local timer causes a huge number of
> retries. Also there is a situation where the CPU which does not handle
> the broadcast timer interrupt exits and reenters broadcast mode before
> the broadcast interrupt got handled by another CPU. This can lead to
> an interesting ping pong of the broadcast and the cpu local timer
> code.
> 
> This series addresses these problems. The first two patches convert
> the broadcast code to proper cpumask_var_t instead of adding more
> bitmaps later.
> 
> The rest of the series is adopted from the quick patches which I
> posted earlier while discussing the issue with Jason et. al.
> 
> Please give it a proper testing on your affected hardware.
> 
I have tested this revised patches on OMAP4 and OMAP5 platforms
with CPUidle enabled against 3.9-rc2. As expected they seems to
work without any issue and also fixes the reported retry issue.

Tested-by: Santosh Shilimkar <santosh.shilimkar at ti.com>




More information about the linux-arm-kernel mailing list