linux-kernel - [PATCH v4 05/11] perf/x86/rapl: Move cpumask variable to rapl

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Message-ID: <20240711102436.4432-6-Dhananjay.Ugwekar@amd.com>
Date: Thu, 11 Jul 2024 10:24:33 +0000
From: Dhananjay Ugwekar <Dhananjay.Ugwekar@....com>
To: <peterz@...radead.org>, <mingo@...hat.com>, <acme@...nel.org>,
	<namhyung@...nel.org>, <mark.rutland@....com>,
	<alexander.shishkin@...ux.intel.com>, <jolsa@...nel.org>,
	<irogers@...gle.com>, <adrian.hunter@...el.com>, <kan.liang@...ux.intel.com>,
	<tglx@...utronix.de>, <bp@...en8.de>, <dave.hansen@...ux.intel.com>,
	<x86@...nel.org>, <kees@...nel.org>, <gustavoars@...nel.org>,
	<rui.zhang@...el.com>, <oleksandr@...alenko.name>
CC: <linux-perf-users@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<linux-hardening@...r.kernel.org>, <ananth.narayan@....com>,
	<gautham.shenoy@....com>, <kprateek.nayak@....com>, <ravi.bangoria@....com>,
	<sandipan.das@....com>, <linux-pm@...r.kernel.org>,
	<Dhananjay.Ugwekar@....com>
Subject: [PATCH v4 05/11] perf/x86/rapl: Move cpumask variable to rapl_pmus struct

This patch is in preparation for addition of per-core energy counter
support for AMD CPUs.

Per-core energy counter PMU will need a separate cpumask. It seems like
a better approach to add the cpumask inside the rapl_pmus struct, instead
of creating another global cpumask variable for per-core PMU. This way, in
future, if there is a need for a new PMU with a different scope (e.g. CCD),
adding a new global cpumask variable won't be necessary.

No functional change.

Signed-off-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@....com>
---
Changes in v4:
* Use cpumask_var_t instead of cpumask_t (Peter)
---
 arch/x86/events/rapl.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/x86/events/rapl.c b/arch/x86/events/rapl.c
index d231a9c068af..e3d0a82e12b9 100644
--- a/arch/x86/events/rapl.c
+++ b/arch/x86/events/rapl.c
@@ -122,6 +122,7 @@ struct rapl_pmu {
 
 struct rapl_pmus {
 	struct pmu		pmu;
+	cpumask_var_t		cpumask;
 	unsigned int		nr_rapl_pmu;
 	struct rapl_pmu		*rapl_pmu[] __counted_by(nr_rapl_pmu);
 };
@@ -142,7 +143,6 @@ struct rapl_model {
  /* 1/2^hw_unit Joule */
 static int rapl_hw_unit[NR_RAPL_DOMAINS] __read_mostly;
 static struct rapl_pmus *rapl_pmus;
-static cpumask_t rapl_cpu_mask;
 static unsigned int rapl_cntr_mask;
 static u64 rapl_timer_ms;
 static struct perf_msr *rapl_msrs;
@@ -401,7 +401,7 @@ static void rapl_pmu_event_read(struct perf_event *event)
 static ssize_t rapl_get_attr_cpumask(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
-	return cpumap_print_to_pagebuf(true, buf, &rapl_cpu_mask);
+	return cpumap_print_to_pagebuf(true, buf, rapl_pmus->cpumask);
 }
 
 static DEVICE_ATTR(cpumask, S_IRUGO, rapl_get_attr_cpumask, NULL);
@@ -572,7 +572,7 @@ static int rapl_cpu_offline(unsigned int cpu)
 	int target;
 
 	/* Check if exiting cpu is used for collecting rapl events */
-	if (!cpumask_test_and_clear_cpu(cpu, &rapl_cpu_mask))
+	if (!cpumask_test_and_clear_cpu(cpu, rapl_pmus->cpumask))
 		return 0;
 
 	rapl_pmu->cpu = -1;
@@ -581,7 +581,7 @@ static int rapl_cpu_offline(unsigned int cpu)
 
 	/* Migrate rapl events to the new target */
 	if (target < nr_cpu_ids) {
-		cpumask_set_cpu(target, &rapl_cpu_mask);
+		cpumask_set_cpu(target, rapl_pmus->cpumask);
 		rapl_pmu->cpu = target;
 		perf_pmu_migrate_context(rapl_pmu->pmu, cpu, target);
 	}
@@ -613,11 +613,11 @@ static int rapl_cpu_online(unsigned int cpu)
 	 * Check if there is an online cpu in the package which collects rapl
 	 * events already.
 	 */
-	target = cpumask_any_and(&rapl_cpu_mask, rapl_pmu_cpumask);
+	target = cpumask_any_and(rapl_pmus->cpumask, rapl_pmu_cpumask);
 	if (target < nr_cpu_ids)
 		return 0;
 
-	cpumask_set_cpu(cpu, &rapl_cpu_mask);
+	cpumask_set_cpu(cpu, rapl_pmus->cpumask);
 	rapl_pmu->cpu = cpu;
 	return 0;
 }
@@ -710,6 +710,9 @@ static int __init init_rapl_pmus(void)
 	rapl_pmus = kzalloc(struct_size(rapl_pmus, rapl_pmu, nr_rapl_pmu), GFP_KERNEL);
 	if (!rapl_pmus)
 		return -ENOMEM;
+
+	if (!alloc_cpumask_var(&rapl_pmus->cpumask, GFP_KERNEL))
+		return -ENOMEM;
 
 	rapl_pmus->nr_rapl_pmu		= nr_rapl_pmu;
 	rapl_pmus->pmu.attr_groups	= rapl_attr_groups;
-- 
2.34.1