bus/arm-ccn: Use cpu-hp's multi instance support instead custom list

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/1471024183-12666-6-git-send-email-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 21 insertions, 33 deletions

diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c
index 97a9185af433..e0ad47534126 100644
--- a/drivers/bus/arm-ccn.c
+++ b/drivers/bus/arm-ccn.c
@@ -167,7 +167,7 @@ struct arm_ccn_dt {
         struct hrtimer hrtimer;
 
         cpumask_t cpu;
-        struct list_head entry;
+        struct hlist_node node;
 
         struct pmu pmu;
 };
@@ -189,9 +189,6 @@ struct arm_ccn {
         struct arm_ccn_dt dt;
 };
 
-static DEFINE_MUTEX(arm_ccn_mutex);
-static LIST_HEAD(arm_ccn_list);
-
 static int arm_ccn_node_to_xp(int node)
 {
         return node / CCN_NUM_XP_PORTS;
@@ -1173,30 +1170,24 @@ static enum hrtimer_restart arm_ccn_pmu_timer_handler(struct hrtimer *hrtimer)
 }
 
 
-static int arm_ccn_pmu_offline_cpu(unsigned int cpu)
+static int arm_ccn_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 {
-        struct arm_ccn_dt *dt;
+        struct arm_ccn_dt *dt = hlist_entry_safe(node, struct arm_ccn_dt, node);
+        struct arm_ccn *ccn = container_of(dt, struct arm_ccn, dt);
         unsigned int target;
 
-        mutex_lock(&arm_ccn_mutex);
-        list_for_each_entry(dt, &arm_ccn_list, entry) {
-                struct arm_ccn *ccn = container_of(dt, struct arm_ccn, dt);
-
-                if (!cpumask_test_and_clear_cpu(cpu, &dt->cpu))
-                        continue;
-                target = cpumask_any_but(cpu_online_mask, cpu);
-                if (target >= nr_cpu_ids)
-                        continue;
-                perf_pmu_migrate_context(&dt->pmu, cpu, target);
-                cpumask_set_cpu(target, &dt->cpu);
-                if (ccn->irq)
-                        WARN_ON(irq_set_affinity_hint(ccn->irq, &dt->cpu) != 0);
-        }
-        mutex_unlock(&arm_ccn_mutex);
+        if (!cpumask_test_and_clear_cpu(cpu, &dt->cpu))
+                return 0;
+        target = cpumask_any_but(cpu_online_mask, cpu);
+        if (target >= nr_cpu_ids)
+                return 0;
+        perf_pmu_migrate_context(&dt->pmu, cpu, target);
+        cpumask_set_cpu(target, &dt->cpu);
+        if (ccn->irq)
+                WARN_ON(irq_set_affinity_hint(ccn->irq, &dt->cpu) != 0);
         return 0;
 }
 
-
 static DEFINE_IDA(arm_ccn_pmu_ida);
 
 static int arm_ccn_pmu_init(struct arm_ccn *ccn)
@@ -1278,9 +1269,8 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn)
         if (err)
                 goto error_pmu_register;
 
-        mutex_lock(&arm_ccn_mutex);
-        list_add(&ccn->dt.entry, &arm_ccn_list);
-        mutex_unlock(&arm_ccn_mutex);
+        cpuhp_state_add_instance_nocalls(CPUHP_AP_PERF_ARM_CCN_ONLINE,
+                                         &ccn->dt.node);
         return 0;
 
 error_pmu_register:
@@ -1296,10 +1286,8 @@ static void arm_ccn_pmu_cleanup(struct arm_ccn *ccn)
 {
         int i;
 
-        mutex_lock(&arm_ccn_mutex);
-        list_del(&ccn->dt.entry);
-        mutex_unlock(&arm_ccn_mutex);
-
+        cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_CCN_ONLINE,
+                                            &ccn->dt.node);
         if (ccn->irq)
                 irq_set_affinity_hint(ccn->irq, NULL);
         for (i = 0; i < ccn->num_xps; i++)
@@ -1527,9 +1515,9 @@ static int __init arm_ccn_init(void)
 {
         int i, ret;
 
-        ret = cpuhp_setup_state_nocalls(CPUHP_AP_PERF_ARM_CCN_ONLINE,
-                                        "AP_PERF_ARM_CCN_ONLINE", NULL,
-                                        arm_ccn_pmu_offline_cpu);
+        ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_CCN_ONLINE,
+                                      "AP_PERF_ARM_CCN_ONLINE", NULL,
+                                      arm_ccn_pmu_offline_cpu);
         if (ret)
                 return ret;
 
@@ -1541,7 +1529,7 @@ static int __init arm_ccn_init(void)
 
 static void __exit arm_ccn_exit(void)
 {
-        cpuhp_remove_state_nocalls(CPUHP_AP_PERF_ARM_CCN_ONLINE);
+        cpuhp_remove_multi_state(CPUHP_AP_PERF_ARM_CCN_ONLINE);
         platform_driver_unregister(&arm_ccn_driver);
 }