From: Like Xu <likexu@xxxxxxxxxxx>
Currently, we have [intel|knc|p4|p6]_perfmon_event_map on the Intel
platforms and amd_[f17h]_perfmon_event_map on the AMD platforms.
Early clumsy KVM code or other potential perf_event users may have
hard-coded these perfmon_maps (e.g., arch/x86/kvm/svm/pmu.c), so
it would not make sense to program a common hardware event based
on the generic "enum perf_hw_id" once the two tables do not match.
Just provide an interface for callers outside the perf subsystem to get
the counter config based on the perfmon_event_map currently in use,
and it also helps to save bytes.
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Signed-off-by: Like Xu <likexu@xxxxxxxxxxx>
---
arch/x86/events/core.c | 11 +++++++++++
arch/x86/include/asm/perf_event.h | 6 ++++++
2 files changed, 17 insertions(+)
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index e686c5e0537b..e760a1348c62 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2996,3 +2996,14 @@ void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
cap->events_mask_len = x86_pmu.events_mask_len;
}
EXPORT_SYMBOL_GPL(perf_get_x86_pmu_capability);
+
+u64 perf_get_hw_event_config(int hw_event)
+{
+ int max = x86_pmu.max_events;
+
+ if (hw_event < max)
+ return x86_pmu.event_map(array_index_nospec(hw_event, max));
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(perf_get_hw_event_config);
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index 8fc1b5003713..822927045406 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -477,6 +477,7 @@ struct x86_pmu_lbr {
};
extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);
+extern u64 perf_get_hw_event_config(int hw_event);
extern void perf_check_microcode(void);
extern void perf_clear_dirty_counters(void);
extern int x86_perf_rdpmc_index(struct perf_event *event);
@@ -486,6 +487,11 @@ static inline void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
memset(cap, 0, sizeof(*cap));
}
+static inline u64 perf_get_hw_event_config(int hw_event)
+{
+ return 0;
+}
+
static inline void perf_events_lapic_init(void) { }
static inline void perf_check_microcode(void) { }
#endif
--
2.35.0
