bus/arm-cci: 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: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: rt@linutronix.de
Cc: Olof Johansson <olof@lixom.net>
Link: http://lkml.kernel.org/r/1471024183-12666-5-git-send-email-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c
index 5755907f836f8d7a6aa5c892e8eef542e6e9c678..4c44ba2d3412badbf63a6cdfbe82a6cf16c6a100 100644 (file)
--- a/drivers/bus/arm-cci.c
+++ b/drivers/bus/arm-cci.c
@@ -144,15 +144,12 @@ struct cci_pmu {
        int num_cntrs;
        atomic_t active_events;
        struct mutex reserve_mutex;
-       struct list_head entry;
+       struct hlist_node node;
        cpumask_t cpus;
 };
 
 #define to_cci_pmu(c)  (container_of(c, struct cci_pmu, pmu))
 
-static DEFINE_MUTEX(cci_pmu_mutex);
-static LIST_HEAD(cci_pmu_list);
-
 enum cci_models {
 #ifdef CONFIG_ARM_CCI400_PMU
        CCI400_R0,
@@ -1506,25 +1503,21 @@ static int cci_pmu_init(struct cci_pmu *cci_pmu, struct platform_device *pdev)
        return perf_pmu_register(&cci_pmu->pmu, name, -1);
 }
 
-static int cci_pmu_offline_cpu(unsigned int cpu)
+static int cci_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
 {
-       struct cci_pmu *cci_pmu;
+       struct cci_pmu *cci_pmu = hlist_entry_safe(node, struct cci_pmu, node);
        unsigned int target;
 
-       mutex_lock(&cci_pmu_mutex);
-       list_for_each_entry(cci_pmu, &cci_pmu_list, entry) {
-               if (!cpumask_test_and_clear_cpu(cpu, &cci_pmu->cpus))
-                       continue;
-               target = cpumask_any_but(cpu_online_mask, cpu);
-               if (target >= nr_cpu_ids)
-                       continue;
-               /*
-                * TODO: migrate context once core races on event->ctx have
-                * been fixed.
-                */
-               cpumask_set_cpu(target, &cci_pmu->cpus);
-       }
-       mutex_unlock(&cci_pmu_mutex);
+       if (!cpumask_test_and_clear_cpu(cpu, &cci_pmu->cpus))
+               return 0;
+       target = cpumask_any_but(cpu_online_mask, cpu);
+       if (target >= nr_cpu_ids)
+               return 0;
+       /*
+        * TODO: migrate context once core races on event->ctx have
+        * been fixed.
+        */
+       cpumask_set_cpu(target, &cci_pmu->cpus);
        return 0;
 }
 
@@ -1768,10 +1761,8 @@ static int cci_pmu_probe(struct platform_device *pdev)
        if (ret)
                return ret;
 
-       mutex_lock(&cci_pmu_mutex);
-       list_add(&cci_pmu->entry, &cci_pmu_list);
-       mutex_unlock(&cci_pmu_mutex);
-
+       cpuhp_state_add_instance_nocalls(CPUHP_AP_PERF_ARM_CCI_ONLINE,
+                                        &cci_pmu->node);
        pr_info("ARM %s PMU driver probed", cci_pmu->model->name);
        return 0;
 }
@@ -1804,9 +1795,9 @@ static int __init cci_platform_init(void)
 {
        int ret;
 
-       ret = cpuhp_setup_state_nocalls(CPUHP_AP_PERF_ARM_CCI_ONLINE,
-                                       "AP_PERF_ARM_CCI_ONLINE", NULL,
-                                       cci_pmu_offline_cpu);
+       ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_CCI_ONLINE,
+                                     "AP_PERF_ARM_CCI_ONLINE", NULL,
+                                     cci_pmu_offline_cpu);
        if (ret)
                return ret;