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 for branch_reg ahead of intel_pebs_constraints. intel_shared_regs_constraints for branch_reg doesn't modify event->hw, so it's safe to be called before intel_pebs_constraints. intel_shared_regs_constraints for branch_reg also special case when it returns &emptyconstraint. It put constraints for extra_reg. This patch remove it. Because it will never get constraints for extra_reg if return is &emptyconstraint. Signed-off-by: Kan Liang <kan.li...@intel.com> --- arch/x86/kernel/cpu/perf_event_intel.c | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 9f1dd18..247780a 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1587,25 +1587,14 @@ __intel_shared_reg_put_constraints(struct cpu_hw_events *cpuc, static struct event_constraint * intel_shared_regs_constraints(struct cpu_hw_events *cpuc, - struct perf_event *event) + struct perf_event *event, + struct hw_perf_event_extra *reg) { - struct event_constraint *c = NULL, *d; - struct hw_perf_event_extra *xreg, *breg; + struct event_constraint *c = NULL; + + if (reg->idx != EXTRA_REG_NONE) + c = __intel_shared_reg_get_constraints(cpuc, event, reg); - xreg = &event->hw.extra_reg; - if (xreg->idx != EXTRA_REG_NONE) { - c = __intel_shared_reg_get_constraints(cpuc, event, xreg); - if (c == &emptyconstraint) - return c; - } - breg = &event->hw.branch_reg; - if (breg->idx != EXTRA_REG_NONE) { - d = __intel_shared_reg_get_constraints(cpuc, event, breg); - if (d == &emptyconstraint) { - __intel_shared_reg_put_constraints(cpuc, xreg); - c = d; - } - } return c; } @@ -1629,17 +1618,18 @@ x86_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) static struct event_constraint * intel_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) { - struct event_constraint *c; + struct event_constraint *c, *d; c = intel_bts_constraints(event); if (c) return c; - c = intel_pebs_constraints(event); - if (c) - return c; + c = intel_shared_regs_constraints(cpuc, event, &event->hw.branch_reg); + d = intel_pebs_constraints(event); + if (d || c) + return (d) ? (d) : (c); - c = intel_shared_regs_constraints(cpuc, event); + c = intel_shared_regs_constraints(cpuc, event, &event->hw.extra_reg); if (c) return c; -- 1.8.3.2 -- 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/