From b4d9e5e88b8f0d71b00928bf8c5d952ce6fbdcc9 Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Thu, 3 May 2018 11:25:08 -0700 Subject: [PATCH] perf/x86/intel/uncore: Correct fixed counter index check in generic code [ Upstream commit 4749f8196452eeb73cf2086a6a9705bae479d33d ] There is no index which is bigger than UNCORE_PMC_IDX_FIXED. The only exception is client IMC uncore, which has been specially handled. For generic code, it is not correct to use >= to check fixed counter. The code quality issue will bring problem when a new counter index is introduced. Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Thomas Gleixner Cc: Linus Torvalds Cc: Peter Zijlstra Cc: acme@kernel.org Cc: eranian@google.com Link: http://lkml.kernel.org/r/1525371913-10597-3-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/perf_event_intel_uncore.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c index 61215a69b03d..b22e9c4dd111 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c @@ -229,7 +229,7 @@ void uncore_perf_event_update(struct intel_uncore_box *box, struct perf_event *e u64 prev_count, new_count, delta; int shift; - if (event->hw.idx >= UNCORE_PMC_IDX_FIXED) + if (event->hw.idx == UNCORE_PMC_IDX_FIXED) shift = 64 - uncore_fixed_ctr_bits(box); else shift = 64 - uncore_perf_ctr_bits(box);