On Tue, Jul 15, 2014 at 4:29 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > On Tue, Jul 15, 2014 at 02:31:41AM +0200, Stephane Eranian wrote: >> PEBS can capture machine state regs at retiremnt of the sampled >> instructions. When precise sampling is enabled on an event, PEBS >> is used, so substitute the interrupted state with the PEBS state. >> Note that not all registers are captured by PEBS. Those missing >> are replaced by the interrupt state counter-parts. >> >> Signed-off-by: Stephane Eranian <eranian@xxxxxxxxxx> >> --- >> arch/x86/kernel/cpu/perf_event_intel_ds.c | 19 +++++++++++++++++++ >> 1 file changed, 19 insertions(+) >> >> diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c >> index 980970c..d612bcd 100644 >> --- a/arch/x86/kernel/cpu/perf_event_intel_ds.c >> +++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c >> @@ -925,6 +925,25 @@ static void __intel_pmu_pebs_event(struct perf_event *event, >> regs.bp = pebs->bp; >> regs.sp = pebs->sp; >> >> + if (sample_type & PERF_SAMPLE_REGS_INTR) { >> + regs.ax = pebs->ax; >> + regs.bx = pebs->bx; >> + regs.cx = pebs->cx; >> + regs.si = pebs->si; >> + regs.di = pebs->di; >> + >> + regs.r8 = pebs->r8; >> + regs.r9 = pebs->r9; >> + regs.r10 = pebs->r10; >> + regs.r11 = pebs->r11; >> + regs.r12 = pebs->r12; >> + regs.r13 = pebs->r13; >> + regs.r14 = pebs->r14; >> + regs.r14 = pebs->r15; >> + >> + data.regs_intr.regs = ®s; > > This last assignment is superfluous. Note how you previous patch's > perf_sample_regs_intr() is unconditionally writing its .regs value, and > in turn, perf_sample_regs_intr() is called unconditionally from > perf_prepare_sample(). > Ok, I will remove it. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/