perf/x86/intel: Filter branches for PEBS event
For supporting Intel LBR branches filtering, Intel LBR sharing logic mechanism is introduced from commit b36817e8 ("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 <kan.liang@intel.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> 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 <mingo@kernel.org>
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