[PATCH 07/15] perf/x86: Plumb counter bitmap from x86_pmu to x86_pmu_cap

[Zide Chen]

From: Dapeng Mi <dapeng1.mi@xxxxxxxxxxxxxxx>

Intel PerfMon v5 introduced CPUID.0AH:ECX to support non-contiguous
fixed counters and Architectural PerfMon Extension leaf (0x23) further
supports non-contiguous general-purpose counters.

num_counters_{gp,fixed} indicates the total number of GP or fixed
counters, but cannot represent non-contiguous counters.

Add cntr_mask and fixed_cntr_mask union so that KVM can get the
accurate counter availability directly from x86_pmu_cap. The u64
alias is convenient for mask arithmetic, while the bitmap form works
with for_each_set_bit() and friends.

num_counters_{gp,fixed} in x86_pmu_capability will be removed once
callers have been converted to the use of {,fixed_}cntr_mask.

Signed-off-by: Dapeng Mi <dapeng1.mi@xxxxxxxxxxxxxxx>
Signed-off-by: Zide Chen <zide.chen@xxxxxxxxx>
---
 arch/x86/events/core.c            | 6 ++++--
 arch/x86/include/asm/perf_event.h | 8 ++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 4b9e105309c6..65349819ba43 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -3134,8 +3134,10 @@ void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
 	cap->version		= x86_pmu.version;
 	cap->num_counters_gp	= x86_pmu_num_counters(NULL);
 	cap->num_counters_fixed	= x86_pmu_num_counters_fixed(NULL);
-	cap->bit_width_gp	= cap->num_counters_gp ? x86_pmu.cntval_bits : 0;
-	cap->bit_width_fixed	= cap->num_counters_fixed ? x86_pmu.cntval_bits : 0;
+	cap->cntr_mask64	= x86_pmu.cntr_mask64;
+	cap->fixed_cntr_mask64	= x86_pmu.fixed_cntr_mask64;
+	cap->bit_width_gp	= cap->cntr_mask64 ? x86_pmu.cntval_bits : 0;
+	cap->bit_width_fixed	= cap->fixed_cntr_mask64 ? x86_pmu.cntval_bits : 0;
 	cap->events_mask	= (unsigned int)x86_pmu.events_maskl;
 	cap->events_mask_len	= x86_pmu.events_mask_len;
 	cap->pebs_ept		= x86_pmu.pebs_ept;
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index bc2e1cbcd9b9..f59a3d466195 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -302,6 +302,14 @@ struct x86_pmu_capability {
 	int		version;
 	int		num_counters_gp;
 	int		num_counters_fixed;
+	union {
+		u64	cntr_mask64;
+		DECLARE_BITMAP(cntr_mask, X86_PMC_IDX_MAX);
+	};
+	union {
+		u64	fixed_cntr_mask64;
+		DECLARE_BITMAP(fixed_cntr_mask, X86_PMC_IDX_MAX);
+	};
 	int		bit_width_gp;
 	int		bit_width_fixed;
 	unsigned int	events_mask;
-- 
2.54.0