RE: [PATCH 07/14] cpufreq: intel_pstate: Skip unnecessary PID resets on init

From: Doug Smythies
Date: Tue Mar 14 2017 - 12:07:32 EST


On 2017.03.12 10:19 Rafael J. Wysocki wrote:

> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> PID controller parameters only need to be initialized if the
> get_target_pstate_use_performance() P-state selection routine
> is going to be used. It is not necessary to initialize them
> otherwise, so don't do that.
>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
> drivers/cpufreq/intel_pstate.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> Index: linux-pm/drivers/cpufreq/intel_pstate.c
> ===================================================================
> --- linux-pm.orig/drivers/cpufreq/intel_pstate.c
> +++ linux-pm/drivers/cpufreq/intel_pstate.c
> @@ -1974,12 +1974,12 @@ static int intel_pstate_init_cpu(unsigne
> intel_pstate_disable_ee(cpunum);
>
> intel_pstate_hwp_enable(cpu);
> + } else if (pstate_funcs.get_target_pstate == get_target_pstate_use_performance) {
> + intel_pstate_pid_reset(cpu);
> }
>
> intel_pstate_get_cpu_pstates(cpu);
>
> - intel_pstate_pid_reset(cpu);
> -
> pr_debug("controlling: cpu %d\n", cpunum);
>
> return 0;

Hi Rafael,

The patch has a long line and scripts/checkpatch.pl complains.

$ scripts/checkpatch.pl rjw_7_14.txt
WARNING: line over 80 characters
#27: FILE: drivers/cpufreq/intel_pstate.c:1977:
+ } else if (pstate_funcs.get_target_pstate == get_target_pstate_use_performance) {

total: 0 errors, 1 warnings, 14 lines checked

Myself, I don't care, and only found this by accident. I am just passing along
the information.

... Doug