[PATCH V4 12/14] perf/x86: Use event_base_rdpmc for RDPMC userspace support

[kan . liang]

From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

The RDPMC index is always re-calculated in RDPMC userspace support,
especially for fixed counters.

The RDPMC index value is stored in variable event_base_rdpmc for kernel
usage, which can be used for RDPMC userspace support as well. Only the
metrics event has to be specially handled.

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
---
 arch/x86/events/core.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 350c21aaea61..10ce4c381425 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2197,20 +2197,16 @@ static void x86_pmu_event_unmapped(struct perf_event *event, struct mm_struct *m
 
 static int x86_pmu_event_idx(struct perf_event *event)
 {
-	int idx = event->hw.idx;
+	struct hw_perf_event *hwc = &event->hw;
 
-	if (!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED))
+	if (!(hwc->flags & PERF_X86_EVENT_RDPMC_ALLOWED))
 		return 0;
 
 	/* Return PERF_METRICS MSR value for metrics event */
-	if (is_metric_idx(idx))
-		idx = 1 << 29;
-	else if (x86_pmu.num_counters_fixed && idx >= INTEL_PMC_IDX_FIXED) {
-		idx -= INTEL_PMC_IDX_FIXED;
-		idx |= 1 << 30;
-	}
-
-	return idx + 1;
+	if (is_metric_idx(hwc->idx))
+		return (1 << 29) + 1;
+	else
+		return hwc->event_base_rdpmc + 1;
 }
 
 static ssize_t get_attr_rdpmc(struct device *cdev,
-- 
2.17.1