Re: [PATCHv2] cpufreq: Fix GOV_LIMITS handling for the userspace governor

[Viresh Kumar <viresh.kumar@linaro.org>]

On 29-04-16, 14:44, Sai Gurrappadi wrote:
> Currently, the userspace governor only updates frequency on GOV_LIMITS
> if policy->cur falls outside policy->{min/max}. However, it is also
> necessary to update current frequency on GOV_LIMITS to match the user
> requested value if it can be achieved within the new policy->{max/min}.
> 
> This was previously the behaviour in the governor until commit d1922f0
> ("cpufreq: Simplify userspace governor") which incorrectly assumed that
> policy->cur == user requested frequency via scaling_setspeed. This won't
> be true if the user requested frequency falls outside policy->{min/max}.
> Ex: a temporary thermal cap throttled the user requested frequency.
> 
> Fix this by storing the user requested frequency in a seperate variable.
> The governor will then try to achieve this request on every GOV_LIMITS
> change.
> 
> Fixes: d1922f02562f ("cpufreq: Simplify userspace governor")
> 
> Signed-off-by: Sai Gurrappadi <sgurrappadi@nvidia.com>
> ---
> 
> Changes in v2:
> - Used policy->governor_data rather than using a per-cpu variable
> 
>  drivers/cpufreq/cpufreq_userspace.c | 43 ++++++++++++++++++++++++++++++++-----
>  1 file changed, 38 insertions(+), 5 deletions(-)

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

-- 
viresh