[PATCH 7.2.y 1/3] s390/pai: Use PAI PMU index as parameter replacing event

[Sasha Levin <sashal@kernel.org>]

From: Thomas Richter <tmricht@linux.ibm.com>

[ Upstream commit 4eef4ab3aa3a32725e5bc79032c722f9f4a90172 ]

Use PAI PMU index value as function argument instead of pointer
to struct perf_event. Only that index value is used inside
functions pai_alloc_cpu() and pai_event_destroy_cpu().
No functional change.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Stable-dep-of: 9ecc4d033879 ("s390/pai: Support CPU hotplug for PMU PAI")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/s390/kernel/perf_pai.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/arch/s390/kernel/perf_pai.c b/arch/s390/kernel/perf_pai.c
index cdb8006220ca0..7c13f5586c793 100644
--- a/arch/s390/kernel/perf_pai.c
+++ b/arch/s390/kernel/perf_pai.c
@@ -140,16 +140,14 @@ static void pai_free(struct pai_mapptr *mp)
 /* Adjust usage counters and remove allocated memory when all users are
  * gone.
  */
-static void pai_event_destroy_cpu(struct perf_event *event, int cpu)
+static void pai_event_destroy_cpu(int idx, int cpu)
 {
-	int idx = PAI_PMU_IDX(event);
 	struct pai_mapptr *mp = per_cpu_ptr(pai_root[idx].mapptr, cpu);
 	struct pai_map *cpump = mp->mapptr;
 
 	mutex_lock(&pai_reserve_mutex);
-	debug_sprintf_event(paidbg, 5, "%s event %#llx idx %d cpu %d users %d "
-			    "refcnt %u\n", __func__, event->attr.config, idx,
-			    event->cpu, cpump->active_events,
+	debug_sprintf_event(paidbg, 5, "%s users %d refcnt %u\n",
+			    __func__, cpump->active_events,
 			    refcount_read(&cpump->refcnt));
 	if (refcount_dec_and_test(&cpump->refcnt))
 		pai_free(mp);
@@ -159,17 +157,17 @@ static void pai_event_destroy_cpu(struct perf_event *event, int cpu)
 
 static void pai_event_destroy(struct perf_event *event)
 {
-	int cpu;
+	int cpu = 0, idx = PAI_PMU_IDX(event);
 
 	free_page(PAI_SAVE_AREA(event));
 	if (event->cpu == -1) {
 		struct cpumask *mask = PAI_CPU_MASK(event);
 
 		for_each_cpu(cpu, mask)
-			pai_event_destroy_cpu(event, cpu);
+			pai_event_destroy_cpu(idx, cpu);
 		kfree(mask);
 	} else {
-		pai_event_destroy_cpu(event, event->cpu);
+		pai_event_destroy_cpu(idx, event->cpu);
 	}
 }
 
@@ -241,12 +239,12 @@ static u64 paicrypt_getall(struct perf_event *event)
  *
  * Allocate the memory for the event.
  */
-static int pai_alloc_cpu(struct perf_event *event, int cpu)
+static int pai_alloc_cpu(int idx, int cpu)
 {
-	int rc, idx = PAI_PMU_IDX(event);
 	struct pai_map *cpump = NULL;
 	bool need_paiext_cb = false;
 	struct pai_mapptr *mp;
+	int rc;
 
 	mutex_lock(&pai_reserve_mutex);
 	/* Allocate root node */
@@ -318,6 +316,7 @@ static int pai_alloc_cpu(struct perf_event *event, int cpu)
 
 static int pai_alloc(struct perf_event *event)
 {
+	int idx = PAI_PMU_IDX(event);
 	struct cpumask *maskptr;
 	int cpu, rc = -ENOMEM;
 
@@ -326,10 +325,10 @@ static int pai_alloc(struct perf_event *event)
 		goto out;
 
 	for_each_online_cpu(cpu) {
-		rc = pai_alloc_cpu(event, cpu);
+		rc = pai_alloc_cpu(idx, cpu);
 		if (rc) {
 			for_each_cpu(cpu, maskptr)
-				pai_event_destroy_cpu(event, cpu);
+				pai_event_destroy_cpu(idx, cpu);
 			kfree(maskptr);
 			goto out;
 		}
@@ -392,7 +391,7 @@ static int pai_event_init(struct perf_event *event, int idx)
 	}
 
 	if (event->cpu >= 0)
-		rc = pai_alloc_cpu(event, event->cpu);
+		rc = pai_alloc_cpu(idx, event->cpu);
 	else
 		rc = pai_alloc(event);
 	if (rc) {
-- 
2.53.0