In heterogeneous systems, the number of counters may differ across
clusters. To find the number of counters for a cluster, we must probe
the PMU from a CPU in that cluster.
Signed-off-by: Mark Rutland <mark.rutl...@arm.com>
Reviewed-by: Will Deacon <will.dea...@arm.com>
---
arch/arm/kernel/perf_event_v7.c | 35 ++++++++++++++++++++---------------
1 file changed, 20 insertions(+), 15 deletions(-)
diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index f4d185e..519948f 100644
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -1226,15 +1226,25 @@ static void armv7pmu_init(struct arm_pmu *cpu_pmu)
cpu_pmu->max_period = (1LLU << 32) - 1;
};
-static u32 armv7_read_num_pmnc_events(void)
+static void armv7_read_num_pmnc_events(void *info)
{
- u32 nb_cnt;
+ int *nb_cnt = info;
/* Read the nb of CNTx counters supported from PMNC */
- nb_cnt = (armv7_pmnc_read() >> ARMV7_PMNC_N_SHIFT) & ARMV7_PMNC_N_MASK;
+ *nb_cnt = (armv7_pmnc_read() >> ARMV7_PMNC_N_SHIFT) & ARMV7_PMNC_N_MASK;
- /* Add the CPU cycles counter and return */
- return nb_cnt + 1;
+ /* Add the CPU cycles counter */
+ *nb_cnt += 1;
+}
+
+static int armv7_probe_num_events(struct arm_pmu *arm_pmu)
+{
+ int ret;
+ ret = smp_call_function_any(&arm_pmu->supported_cpus,
+ armv7_read_num_pmnc_events,
+ &arm_pmu->num_events, 1);
+
+ return ret;
}
static int armv7_a8_pmu_init(struct arm_pmu *cpu_pmu)
@@ -1242,8 +1252,7 @@ static int armv7_a8_pmu_init(struct arm_pmu *cpu_pmu)
armv7pmu_init(cpu_pmu);
cpu_pmu->name = "ARMv7_Cortex_A8";
cpu_pmu->map_event = armv7_a8_map_event;
- cpu_pmu->num_events = armv7_read_num_pmnc_events();
- return 0;
+ return armv7_probe_num_events(cpu_pmu);
}
static int armv7_a9_pmu_init(struct arm_pmu *cpu_pmu)
@@ -1251,8 +1260,7 @@ static int armv7_a9_pmu_init(struct arm_pmu *cpu_pmu)
armv7pmu_init(cpu_pmu);
cpu_pmu->name = "ARMv7_Cortex_A9";
cpu_pmu->map_event = armv7_a9_map_event;
- cpu_pmu->num_events = armv7_read_num_pmnc_events();
- return 0;
+ return armv7_probe_num_events(cpu_pmu);
}
static int armv7_a5_pmu_init(struct arm_pmu *cpu_pmu)
@@ -1260,8 +1268,7 @@ static int armv7_a5_pmu_init(struct arm_pmu *cpu_pmu)
armv7pmu_init(cpu_pmu);
cpu_pmu->name = "ARMv7_Cortex_A5";
cpu_pmu->map_event = armv7_a5_map_event;
- cpu_pmu->num_events = armv7_read_num_pmnc_events();
- return 0;
+ return armv7_probe_num_events(cpu_pmu);
}
static int armv7_a15_pmu_init(struct arm_pmu *cpu_pmu)
@@ -1269,9 +1276,8 @@ static int armv7_a15_pmu_init(struct arm_pmu *cpu_pmu)
armv7pmu_init(cpu_pmu);
cpu_pmu->name = "ARMv7_Cortex_A15";
cpu_pmu->map_event = armv7_a15_map_event;
- cpu_pmu->num_events = armv7_read_num_pmnc_events();
cpu_pmu->set_event_filter = armv7pmu_set_event_filter;
- return 0;
+ return armv7_probe_num_events(cpu_pmu);
}
static int armv7_a7_pmu_init(struct arm_pmu *cpu_pmu)
@@ -1279,9 +1285,8 @@ static int armv7_a7_pmu_init(struct arm_pmu *cpu_pmu)
armv7pmu_init(cpu_pmu);
cpu_pmu->name = "ARMv7_Cortex_A7";
cpu_pmu->map_event = armv7_a7_map_event;
- cpu_pmu->num_events = armv7_read_num_pmnc_events();
cpu_pmu->set_event_filter = armv7pmu_set_event_filter;
- return 0;
+ return armv7_probe_num_events(cpu_pmu);
}
#else
static inline int armv7_a8_pmu_init(struct arm_pmu *cpu_pmu)
--
1.8.1.1
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