Commit 75608cb0 authored Jul 23, 2020 by Kan Liang Committed by Peter Zijlstra Aug 18, 2020

perf/x86: Use event_base_rdpmc for the RDPMC userspace support



The RDPMC index is always re-calculated for the RDPMC userspace support,
which is unnecessary.

The RDPMC index value is stored in the variable event_base_rdpmc for
the kernel usage, which can be used for RDPMC userspace support as well.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-2-kan.liang@linux.intel.com

parent 9123e3a7

arch/x86/events/core.c

+3 −8

Original line number	Diff line number	Diff line
		@@ -2208,17 +2208,12 @@ 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;

		if (x86_pmu.num_counters_fixed && idx >= INTEL_PMC_IDX_FIXED) {
		idx -= INTEL_PMC_IDX_FIXED;
		idx \|= 1 << 30;
		}

		return idx + 1;
		return hwc->event_base_rdpmc + 1;
		}

		static ssize_t get_attr_rdpmc(struct device *cdev,

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