linux-kernel - Re: [PATCH 2/2] cpufreq: powernv: Use PMSR to verify global and local pstate

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Message-ID: <20161104064132.GB3414@vireshk-i7>
Date:   Fri, 4 Nov 2016 12:11:32 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Akshay Adiga <akshay.adiga@...ux.vnet.ibm.com>
Cc:     rjw@...ysocki.net, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org
Subject: Re: [PATCH 2/2] cpufreq: powernv: Use PMSR to verify global and
 local pstate

On 04-11-16, 10:57, Akshay Adiga wrote:
> As fast_switch may get called in interrupt disable mode, it does not

s/in interrupt disable mode/with interrupts disabled
s/it does/it may

> update the global_pstate_info data structure. Hence the global_pstate_info
> has stale data whenever pstate is updated through fast_swtich().

s/has/may have
s/swtich/switch

> 
> So the gpstate_timer can fire after a fast_switch() call has update

s/So the/The
s/a fast_swtich() call has update/the fast_switch() call has updated

> the pstates to a different value. Hence the timer handler cannot rely
> on the cached values of local and global pstate and needs to read it
> from the PMSR. 
> 
> Signed-off-by: Akshay Adiga <akshay.adiga@...ux.vnet.ibm.com>
> 
> ---
>  drivers/cpufreq/powernv-cpufreq.c | 32 ++++++++++++++++++++++----------
>  1 file changed, 22 insertions(+), 10 deletions(-)

I am not the best guy to judge the code changes here. Can you please include
Shilpa and Gautham to the mail chain and get there feedback.

-- 
viresh