From: Sandipan Das <sandipan.das@amd.com>

Date: Thu, 19 May 2022 15:33:30 +0530

Subject: perf/x86/amd/uncore: Use dynamic events array

Git-commit: 39621c5808f5dda75d03dc4b2d4d2b13a5a1c34b

Patch-mainline: v6.0-rc1

References: jsc#PED-1754 (PerfMonV2), jsc#PED-1752

If AMD Performance Monitoring Version 2 (PerfMonV2) is

supported, the number of available counters for a given

uncore PMU may not be fixed across families and models

and has to be determined at runtime.

The per-cpu uncore PMU data currently uses a fixed-sized

array for event information. Make it dynamic based on the

number of available counters.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Link: https://lore.kernel.org/r/21eea0cb6de9d14f78d52d1d62637ae02bc900f5.1652954372.git.sandipan.das@amd.com

Signed-off-by: Tony Jones <tonyj@suse.de>

---

 arch/x86/events/amd/uncore.c | 38 +++++++++++++++++++++++++++++++-------

 1 file changed, 31 insertions(+), 7 deletions(-)

diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c

index 0d04414b97d2..8dfcf93711ab 100644

--- a/arch/x86/events/amd/uncore.c

+++ b/arch/x86/events/amd/uncore.c

@@ -21,7 +21,6 @@

 #define NUM_COUNTERS_NB		4

 #define NUM_COUNTERS_L2		4

 #define NUM_COUNTERS_L3		6

-#define MAX_COUNTERS		6

 #define RDPMC_BASE_NB		6

 #define RDPMC_BASE_LLC		10

@@ -46,7 +45,7 @@ struct amd_uncore {

 	u32 msr_base;

 	cpumask_t *active_mask;

 	struct pmu *pmu;

-	struct perf_event *events[MAX_COUNTERS];

+	struct perf_event **events;

 	struct hlist_node node;

 };

@@ -370,11 +369,19 @@ static struct amd_uncore *amd_uncore_alloc(unsigned int cpu)

 			cpu_to_node(cpu));

 }

+static inline struct perf_event **

+amd_uncore_events_alloc(unsigned int num, unsigned int cpu)

+{

+	return kzalloc_node(sizeof(struct perf_event *) * num, GFP_KERNEL,

+			    cpu_to_node(cpu));

+}

+

 static int amd_uncore_cpu_up_prepare(unsigned int cpu)

 {

-	struct amd_uncore *uncore_nb = NULL, *uncore_llc;

+	struct amd_uncore *uncore_nb = NULL, *uncore_llc = NULL;

 	if (amd_uncore_nb) {

+		*per_cpu_ptr(amd_uncore_nb, cpu) = NULL;

 		uncore_nb = amd_uncore_alloc(cpu);

 		if (!uncore_nb)

 			goto fail;

@@ -384,11 +391,15 @@ static int amd_uncore_cpu_up_prepare(unsigned int cpu)

 		uncore_nb->msr_base = MSR_F15H_NB_PERF_CTL;

 		uncore_nb->active_mask = &amd_nb_active_mask;

 		uncore_nb->pmu = &amd_nb_pmu;

+		uncore_nb->events = amd_uncore_events_alloc(num_counters_nb, cpu);

+		if (!uncore_nb->events)

+			goto fail;

 		uncore_nb->id = -1;

 		*per_cpu_ptr(amd_uncore_nb, cpu) = uncore_nb;

 	}

 	if (amd_uncore_llc) {

+		*per_cpu_ptr(amd_uncore_llc, cpu) = NULL;

 		uncore_llc = amd_uncore_alloc(cpu);

 		if (!uncore_llc)

 			goto fail;

@@ -398,6 +409,9 @@ static int amd_uncore_cpu_up_prepare(unsigned int cpu)

 		uncore_llc->msr_base = MSR_F16H_L2I_PERF_CTL;

 		uncore_llc->active_mask = &amd_llc_active_mask;

 		uncore_llc->pmu = &amd_llc_pmu;

+		uncore_llc->events = amd_uncore_events_alloc(num_counters_llc, cpu);

+		if (!uncore_llc->events)

+			goto fail;

 		uncore_llc->id = -1;

 		*per_cpu_ptr(amd_uncore_llc, cpu) = uncore_llc;

 	}

@@ -405,9 +419,16 @@ static int amd_uncore_cpu_up_prepare(unsigned int cpu)

 	return 0;

 fail:

-	if (amd_uncore_nb)

-		*per_cpu_ptr(amd_uncore_nb, cpu) = NULL;

-	kfree(uncore_nb);

+	if (uncore_nb) {

+		kfree(uncore_nb->events);

+		kfree(uncore_nb);

+	}

+

+	if (uncore_llc) {

+		kfree(uncore_llc->events);

+		kfree(uncore_llc);

+	}

+

 	return -ENOMEM;

 }

@@ -540,8 +561,11 @@ static void uncore_dead(unsigned int cpu, struct amd_uncore * __percpu *uncores)

 	if (cpu == uncore->cpu)

 		cpumask_clear_cpu(cpu, uncore->active_mask);

-	if (!--uncore->refcnt)

+	if (!--uncore->refcnt) {

+		kfree(uncore->events);

 		kfree(uncore);

+	}

+

 	*per_cpu_ptr(uncores, cpu) = NULL;

 }