From: Kan Liang <kan.li...@intel.com> For supporting Intel LBR branches filtering, Intel LBR sharing logic mechanism is introduced from commit b36817e88630 ("perf/x86: Add Intel LBR sharing logic"). It modifies __intel_shared_reg_get_constraints to config lbr_sel, which is finally used to set LBR_SELECT. However, the intel_shared_regs_constraints is called after intel_pebs_constraints. The PEBS event will return immediately after intel_pebs_constraints. So it's impossible to filter branches for PEBS event.
This patch move intel_shared_regs_constraints ahead of intel_pebs_constraints. We can safely do that because the intel_shared_regs_constraints only returns emptyconstraint if its rejecting the event, otherwise it returns NULL such that we continue calling intel_pebs_constraints and x86_get_event_constraint. Signed-off-by: Kan Liang <kan.li...@intel.com> --- Changes since V1: - Move all shared regs ahead of intel_pebs_constraints - Modify the description and quote Peter's comments. arch/x86/kernel/cpu/perf_event_intel.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 9f1dd18..83bee99 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1635,11 +1635,11 @@ intel_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event if (c) return c; - c = intel_pebs_constraints(event); + c = intel_shared_regs_constraints(cpuc, event); if (c) return c; - c = intel_shared_regs_constraints(cpuc, event); + c = intel_pebs_constraints(event); if (c) return c; -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/