Re: [PATCH] thermal: cpu_cooling: Actually trace CPU load in thermal_power_cpu_get_power

From: Viresh Kumar
Date: Fri May 03 2019 - 03:21:52 EST


On 02-05-19, 11:32, Matthias Kaehlcke wrote:
> The CPU load values passed to the thermal_power_cpu_get_power
> tracepoint are zero for all CPUs, unless, unless the
> thermal_power_cpu_limit tracepoint is enabled too:
>
> irq/41-rockchip-98 [000] .... 290.972410: thermal_power_cpu_get_power:
> cpus=0000000f freq=1800000 load={{0x0,0x0,0x0,0x0}} dynamic_power=4815
>
> vs
>
> irq/41-rockchip-96 [000] .... 95.773585: thermal_power_cpu_get_power:
> cpus=0000000f freq=1800000 load={{0x56,0x64,0x64,0x5e}} dynamic_power=4959
> irq/41-rockchip-96 [000] .... 95.773596: thermal_power_cpu_limit:
> cpus=0000000f freq=408000 cdev_state=10 power=416
>
> There seems to be no good reason for omitting the CPU load information
> depending on another tracepoint. My guess is that the intention was to
> check whether thermal_power_cpu_get_power is (still) enabled, however
> 'load_cpu != NULL' already indicates that it was at least enabled when
> cpufreq_get_requested_power() was entered, there seems little gain
> from omitting the assignment if the tracepoint was just disabled, so
> just remove the check.
>
> Fixes: 6828a4711f99 ("thermal: add trace events to the power allocator governor")
> Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> ---
> drivers/thermal/cpu_cooling.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> index f7c1f49ec87f..b437804e099b 100644
> --- a/drivers/thermal/cpu_cooling.c
> +++ b/drivers/thermal/cpu_cooling.c
> @@ -458,7 +458,7 @@ static int cpufreq_get_requested_power(struct thermal_cooling_device *cdev,
> load = 0;
>
> total_load += load;
> - if (trace_thermal_power_cpu_limit_enabled() && load_cpu)
> + if (load_cpu)
> load_cpu[i] = load;
>
> i++;

@Javi: I find this change to be fine, do you have any comments on this ?

--
viresh