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    SubjectRe: [PATCH 3/3] cpufreq, powernow-k7: Fix double invocation of cpufreq_freq_transition_begin/end
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    On 25 April 2014 13:48, Srivatsa S. Bhat
    <srivatsa.bhat@linux.vnet.ibm.com> wrote:
    > During frequency transitions, the cpufreq core takes the responsibility of
    > invoking cpufreq_freq_transition_begin() and cpufreq_freq_transition_end()
    > for those cpufreq drivers that define the ->target_index callback but don't
    > set the ASYNC_NOTIFICATION flag.
    >
    > The powernow-k7 cpufreq driver falls under this category, but this driver was
    > invoking the _begin() and _end() APIs itself around frequency transitions,
    > which led to double invocation of the _begin() API. The _begin API makes
    > contending callers wait until the previous invocation is complete. Hence,
    > the powernow-k7 driver ended up waiting on itself, leading to system hangs
    > during boot.
    >
    > Fix this by removing the calls to the _begin() and _end() APIs from the
    > powernow-k7 driver, since they rightly belong to the cpufreq core.
    >
    > Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
    > ---
    >
    > drivers/cpufreq/powernow-k7.c | 4 ----
    > 1 file changed, 4 deletions(-)

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


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