Re: [PATCH v6 05/10] perf/x86/rapl: Make rapl_model struct global

["Gautham R. Shenoy" <gautham.shenoy@amd.com>]

On Fri, Oct 25, 2024 at 11:13:43AM +0000, Dhananjay Ugwekar wrote:
> Prepare for the addition of RAPL core energy counter support.
> 
> As there will always be just one rapl_model variable on a system, make it
> global, to make it easier to access it from any function.
> 
> No functional change.
> 
> Signed-off-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>

LGTM.

Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>

--
Thanks and Regards
gautham.

> ---
>  arch/x86/events/rapl.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/x86/events/rapl.c b/arch/x86/events/rapl.c
> index 7387bca95018..447f62caa5f9 100644
> --- a/arch/x86/events/rapl.c
> +++ b/arch/x86/events/rapl.c
> @@ -151,6 +151,7 @@ static struct rapl_pmus *rapl_pmus;
>  static unsigned int rapl_cntr_mask;
>  static u64 rapl_timer_ms;
>  static struct perf_msr *rapl_msrs;
> +static struct rapl_model *rapl_model;
>  
>  /*
>   * Helper function to get the correct topology id according to the
> @@ -536,18 +537,18 @@ static struct perf_msr amd_rapl_msrs[] = {
>  	[PERF_RAPL_PSYS] = { 0, &rapl_events_psys_group,  NULL, false, 0 },
>  };
>  
> -static int rapl_check_hw_unit(struct rapl_model *rm)
> +static int rapl_check_hw_unit(void)
>  {
>  	u64 msr_rapl_power_unit_bits;
>  	int i;
>  
>  	/* protect rdmsrl() to handle virtualization */
> -	if (rdmsrl_safe(rm->msr_power_unit, &msr_rapl_power_unit_bits))
> +	if (rdmsrl_safe(rapl_model->msr_power_unit, &msr_rapl_power_unit_bits))
>  		return -1;
>  	for (i = 0; i < NR_RAPL_DOMAINS; i++)
>  		rapl_hw_unit[i] = (msr_rapl_power_unit_bits >> 8) & 0x1FULL;
>  
> -	switch (rm->unit_quirk) {
> +	switch (rapl_model->unit_quirk) {
>  	/*
>  	 * DRAM domain on HSW server and KNL has fixed energy unit which can be
>  	 * different than the unit from power unit MSR. See
> @@ -792,21 +793,20 @@ MODULE_DEVICE_TABLE(x86cpu, rapl_model_match);
>  static int __init rapl_pmu_init(void)
>  {
>  	const struct x86_cpu_id *id;
> -	struct rapl_model *rm;
>  	int ret;
>  
>  	id = x86_match_cpu(rapl_model_match);
>  	if (!id)
>  		return -ENODEV;
>  
> -	rm = (struct rapl_model *) id->driver_data;
> +	rapl_model = (struct rapl_model *) id->driver_data;
>  
> -	rapl_msrs = rm->rapl_msrs;
> +	rapl_msrs = rapl_model->rapl_msrs;
>  
>  	rapl_cntr_mask = perf_msr_probe(rapl_msrs, PERF_RAPL_MAX,
> -					false, (void *) &rm->events);
> +					false, (void *) &rapl_model->events);
>  
> -	ret = rapl_check_hw_unit(rm);
> +	ret = rapl_check_hw_unit();
>  	if (ret)
>  		return ret;
>  
> -- 
> 2.34.1
>