Messages in this thread | | | Subject | Re: [PATCH v5 08/11] arm-cci: Provide hook for writing to PMU counters | From | "Suzuki K. Poulose" <> | Date | Mon, 11 Jan 2016 12:14:56 +0000 |
| |
On 11/01/16 10:54, Mark Rutland wrote: > On Mon, Jan 04, 2016 at 11:54:47AM +0000, Suzuki K. Poulose wrote:
>> static struct cci_pmu_model cci_pmu_models[]; >> @@ -846,7 +847,15 @@ static void pmu_write_counter(struct perf_event *event, u32 value) >> dev_err(&cci_pmu->plat_device->dev, "Invalid CCI PMU counter %d\n", idx); >> return; >> } >> - __pmu_write_counter(cci_pmu, value, idx); >> + >> + if (cci_pmu->model->write_counters) { >> + unsigned long mask[BITS_TO_LONGS(cci_pmu->num_cntrs)]; >> + >> + memset(mask, 0, BITS_TO_LONGS(cci_pmu->num_cntrs) * sizeof(unsigned long)); >> + set_bit(idx, mask); >> + cci_pmu->model->write_counters(cci_pmu, mask, value); >> + } else >> + __pmu_write_counter(cci_pmu, value, idx); >> } > > It would be much simpler to always log writes here, and only do the real > wirtes in batches when we re-enable the PMU (with appropriate > disable/enable calls in the IRQ handler). > > We'd still need special hooks for CCIs which require a special dance to > program them, but all the logic to handle the writes would be in one > place.
This one is only there for the writes from the irq handler. Now that we have decided to disable pmu there, we could batch this one too.
Cheers Suzuki
| |