perf/x86/rapl: Make rapl_model struct global

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>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: "Gautham R. Shenoy" <gautham.shenoy@amd.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lore.kernel.org/r/20241115060805.447565-6-Dhananjay.Ugwekar@amd.com

Author: dhananjay-AMD

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
@@ -542,18 +543,18 @@ 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
@@ -798,21 +799,20 @@ 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;