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SubjectRe: [patch 09/13] cpufreq/ia64: Replace racy task affinity logic
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@linutronix.de>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Viresh Kumar <viresh.kumar@linaro.org>
> Cc: Tony Luck <tony.luck@intel.com>
> Cc: Fenghua Yu <fenghua.yu@intel.com>
> Cc: linux-pm@vger.kernel.org
> ---
> drivers/cpufreq/ia64-acpi-cpufreq.c | 91 +++++++++++++++---------------------
> 1 file changed, 38 insertions(+), 53 deletions(-)

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

--
viresh

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