On Tue, Jun 09, 2015 at 05:49:28PM +0530, Vineet Gupta wrote: > From: Alexey Brodkin <[email protected]>
-ENOCHANGELOG > Cc: Peter Zijlstra <[email protected]> > Cc: Arnaldo Carvalho de Melo <[email protected]> > Signed-off-by: Alexey Brodkin <[email protected]> > Signed-off-by: Vineet Gupta <[email protected]> > --- > struct arc_pmu { > struct pmu pmu; > + int has_interrupts; we have pmu::flags & PERF_PMU_CAP_NO_INTERRUPT > @@ -186,7 +189,8 @@ static int arc_pmu_event_init(struct perf_event *event) > hwc->last_period = hwc->sample_period; > local64_set(&hwc->period_left, hwc->sample_period); > } else > - return -ENOENT; > + if (!arc_pmu->has_interrupts) > + return -ENOENT; Same as before, first determine if the event is yours, then return a fatal error. > @@ -307,6 +311,17 @@ static void arc_pmu_stop(struct perf_event *event, int > flags) > struct hw_perf_event *hwc = &event->hw; > int idx = hwc->idx; > > + /* Disable interrupt for this counter */ > + if (is_sampling_event(event)) { but but but, a sampling event needs the interrupt enabled? > + /* > + * Reset interrupt flag by writing of 1. This is required > + * to make sure pending interrupt was not left. > + */ Would not typically the interrupt latch be a property of the interrupt controller, not the device generating it? That is, how can the device programming affect pending interrupts? > + write_aux_reg(ARC_REG_PCT_INT_ACT, 1 << idx); > + write_aux_reg(ARC_REG_PCT_INT_CTRL, > + read_aux_reg(ARC_REG_PCT_INT_CTRL) & ~(1 << idx)); > + } > + > + if (is_sampling_event(event)) { > + /* Mimic full counter overflow as other arches do */ With this you mean the pretending we have 63bit of overflow counter? > + write_aux_reg(ARC_REG_PCT_INT_CNTL, arc_pmu->max_period & > + 0xffffffff); Would not (u32)arc_pmu->max_period, be clearer? > + write_aux_reg(ARC_REG_PCT_INT_CNTH, > + (arc_pmu->max_period >> 32)); But should you not program: min(period, max_period) instead? If the requested period is shorter than your max period you do not want to program the max. Or are you missing a negative somewhere? That is, program the max_period for !sampling events to deal with overflow folding. > + > + /* Enable interrupt for this counter */ > + write_aux_reg(ARC_REG_PCT_INT_CTRL, > + read_aux_reg(ARC_REG_PCT_INT_CTRL) | (1 << idx)); > + } > + > write_aux_reg(ARC_REG_PCT_CONFIG, 0); > write_aux_reg(ARC_REG_PCT_COUNTL, 0); > write_aux_reg(ARC_REG_PCT_COUNTH, 0); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
