Re: [patch 09/13] cpufreq/ia64: Replace racy task affinity logic

[Viresh Kumar]

On 12-04-17, 22:07, Thomas Gleixner wrote:
> The get() and target() callbacks must run on the affected cpu. This is
> achieved by temporarily setting the affinity of the calling thread to the
> requested CPU and reset it to the original affinity afterwards.
> 
> That's racy vs. concurrent affinity settings for that thread resulting in
> code executing on the wrong CPU and overwriting the new affinity setting.
> 
> Replace it by work_on_cpu(). All call pathes which invoke the callbacks are
> already protected against CPU hotplug.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> Cc: Tony Luck <tony.luck@xxxxxxxxx>
> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> Cc: linux-pm@xxxxxxxxxxxxxxx
> ---
>  drivers/cpufreq/ia64-acpi-cpufreq.c |   91 +++++++++++++++---------------------
>  1 file changed, 38 insertions(+), 53 deletions(-)

Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

-- 
viresh