From: Kan Liang Date: Fri, 27 Mar 2015 14:38:25 +0000 (-0400) Subject: perf/x86/intel: Filter branches for PEBS event X-Git-Tag: v6.6-pxa1908~21444^2~1 X-Git-Url: https://git.dujemihanovic.xyz/?a=commitdiff_plain;h=687805e4a60fe83a11556c041840161f8016a367;p=linux.git perf/x86/intel: Filter branches for PEBS event 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() function 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 events. This patch moves intel_shared_regs_constraints() ahead of intel_pebs_constraints(). We can safely do that because the intel_shared_regs_constraints() function only returns empty constraint 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 Signed-off-by: Peter Zijlstra (Intel) Cc: eranian@google.com Link: http://lkml.kernel.org/r/1427467105-9260-1-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 498b6d967138..40898abdff20 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1649,11 +1649,11 @@ 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;