perf, x86: Expose perf capability to other modules
KVM needs to know perf capability to decide which PMU it can expose to a
guest.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1320929850-10480-8-git-send-email-gleb@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index c6998bc..b50e9d1 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -95,6 +95,15 @@
unsigned int full;
};
+struct x86_pmu_capability {
+ int version;
+ int num_counters_gp;
+ int num_counters_fixed;
+ int bit_width_gp;
+ int bit_width_fixed;
+ unsigned int events_mask;
+ int events_mask_len;
+};
/*
* Fixed-purpose performance events:
@@ -216,6 +225,7 @@
};
extern struct perf_guest_switch_msr *perf_guest_get_msrs(int *nr);
+extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);
#else
static inline perf_guest_switch_msr *perf_guest_get_msrs(int *nr)
{
@@ -223,6 +233,11 @@
return NULL;
}
+static inline void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
+{
+ memset(cap, 0, sizeof(*cap));
+}
+
static inline void perf_events_lapic_init(void) { }
#endif
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 55889e0..930fe48 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -1696,3 +1696,15 @@
return misc;
}
+
+void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
+{
+ cap->version = x86_pmu.version;
+ cap->num_counters_gp = x86_pmu.num_counters;
+ cap->num_counters_fixed = x86_pmu.num_counters_fixed;
+ cap->bit_width_gp = x86_pmu.cntval_bits;
+ cap->bit_width_fixed = x86_pmu.cntval_bits;
+ cap->events_mask = (unsigned int)x86_pmu.events_maskl;
+ cap->events_mask_len = x86_pmu.events_mask_len;
+}
+EXPORT_SYMBOL_GPL(perf_get_x86_pmu_capability);