return delta;
}
-static void riscv_pmu_stop(struct perf_event *event, int flags)
+void riscv_pmu_stop(struct perf_event *event, int flags)
{
struct hw_perf_event *hwc = &event->hw;
struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
return overflow;
}
-static void riscv_pmu_start(struct perf_event *event, int flags)
+void riscv_pmu_start(struct perf_event *event, int flags)
{
struct hw_perf_event *hwc = &event->hw;
struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
#include <linux/irqdomain.h>
#include <linux/of_irq.h>
#include <linux/of.h>
+#include <linux/cpu_pm.h>
#include <asm/sbi.h>
#include <asm/hwcap.h>
return 0;
}
+#ifdef CONFIG_CPU_PM
+static int riscv_pm_pmu_notify(struct notifier_block *b, unsigned long cmd,
+ void *v)
+{
+ struct riscv_pmu *rvpmu = container_of(b, struct riscv_pmu, riscv_pm_nb);
+ struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events);
+ int enabled = bitmap_weight(cpuc->used_hw_ctrs, RISCV_MAX_COUNTERS);
+ struct perf_event *event;
+ int idx;
+
+ if (!enabled)
+ return NOTIFY_OK;
+
+ for (idx = 0; idx < RISCV_MAX_COUNTERS; idx++) {
+ event = cpuc->events[idx];
+ if (!event)
+ continue;
+
+ switch (cmd) {
+ case CPU_PM_ENTER:
+ /*
+ * Stop and update the counter
+ */
+ riscv_pmu_stop(event, PERF_EF_UPDATE);
+ break;
+ case CPU_PM_EXIT:
+ case CPU_PM_ENTER_FAILED:
+ /*
+ * Restore and enable the counter.
+ *
+ * Requires RCU read locking to be functional,
+ * wrap the call within RCU_NONIDLE to make the
+ * RCU subsystem aware this cpu is not idle from
+ * an RCU perspective for the riscv_pmu_start() call
+ * duration.
+ */
+ RCU_NONIDLE(riscv_pmu_start(event, PERF_EF_RELOAD));
+ break;
+ default:
+ break;
+ }
+ }
+
+ return NOTIFY_OK;
+}
+
+static int riscv_pm_pmu_register(struct riscv_pmu *pmu)
+{
+ pmu->riscv_pm_nb.notifier_call = riscv_pm_pmu_notify;
+ return cpu_pm_register_notifier(&pmu->riscv_pm_nb);
+}
+
+static void riscv_pm_pmu_unregister(struct riscv_pmu *pmu)
+{
+ cpu_pm_unregister_notifier(&pmu->riscv_pm_nb);
+}
+#else
+static inline int riscv_pm_pmu_register(struct riscv_pmu *pmu) { return 0; }
+static inline void riscv_pm_pmu_unregister(struct riscv_pmu *pmu) { }
+#endif
+
+static void riscv_pmu_destroy(struct riscv_pmu *pmu)
+{
+ riscv_pm_pmu_unregister(pmu);
+ cpuhp_state_remove_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node);
+}
+
static int pmu_sbi_device_probe(struct platform_device *pdev)
{
struct riscv_pmu *pmu = NULL;
if (ret)
return ret;
+ ret = riscv_pm_pmu_register(pmu);
+ if (ret)
+ goto out_unregister;
+
ret = perf_pmu_register(&pmu->pmu, "cpu", PERF_TYPE_RAW);
- if (ret) {
- cpuhp_state_remove_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node);
- return ret;
- }
+ if (ret)
+ goto out_unregister;
return 0;
+out_unregister:
+ riscv_pmu_destroy(pmu);
+
out_free:
kfree(pmu);
return ret;
struct cpu_hw_events __percpu *hw_events;
struct hlist_node node;
+ struct notifier_block riscv_pm_nb;
};
#define to_riscv_pmu(p) (container_of(p, struct riscv_pmu, pmu))
+
+void riscv_pmu_start(struct perf_event *event, int flags);
+void riscv_pmu_stop(struct perf_event *event, int flags);
unsigned long riscv_pmu_ctr_read_csr(unsigned long csr);
int riscv_pmu_event_set_period(struct perf_event *event);
uint64_t riscv_pmu_ctr_get_width_mask(struct perf_event *event);