Messages in this thread - First message in thread
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
- "Yan, Zheng"
| | | Date | Wed, 2 Jul 2014 12:21:47 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH V4 07/16] perf, x86: track number of events that use LBR callstack |
| |
On Mon, Jun 30, 2014 at 04:50:44PM +0800, Yan, Zheng wrote: > +static inline bool branch_user_callstack(unsigned br_sel) > +{ > + return (br_sel & X86_BR_USER) && (br_sel & X86_BR_CALL_STACK); > +} > + > void intel_pmu_lbr_enable(struct perf_event *event) > { > struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); > + struct x86_perf_task_context *task_ctx; > > if (!x86_pmu.lbr_nr) > return; > @@ -214,6 +220,10 @@ void intel_pmu_lbr_enable(struct perf_event *event) > } > cpuc->br_sel = event->hw.branch_reg.reg; > > + task_ctx = event->ctx ? event->ctx->task_ctx_data : NULL; > + if (branch_user_callstack(cpuc->br_sel)) > + task_ctx->lbr_callstack_users++; > +
So what happens if we make a per-cpu event which satisfies branch_user_callstack() ? [unhandled content-type:application/pgp-signature] | |