Hi, Yicong
On 2023/6/6 22:22, Yicong Yang wrote:
From: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
The PTT trace collects PCIe TLP headers from the PCIe link and don't
have the ability to exclude certain context. It doesn't support itrace
as well. So only advertise PERF_PMU_CAP_NO_EXCLUDE. This will greatly
save the storage of final data. Tested tracing idle link for ~15s,
without this patch we'll collect ~28.682MB data for context related
information and with this patch it reduced to ~0.226MB.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
---
drivers/hwtracing/ptt/hisi_ptt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
index 5c7e93e7705f..ff2c16efe5b1 100644
--- a/drivers/hwtracing/ptt/hisi_ptt.c
+++ b/drivers/hwtracing/ptt/hisi_ptt.c
@@ -1210,7 +1210,7 @@ static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
hisi_ptt->hisi_ptt_pmu = (struct pmu) {
.module = THIS_MODULE,
- .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
According to the error prompt of function hisi_ptt_trace_start().
https://elixir.bootlin.com/linux/v6.4-rc7/source/drivers/hwtracing/ptt/hisi_ptt.c#L197
You may be need to keep advertise PERF_PMU_CAP_EXCLUSIVE?
Such pmus can only have one event scheduled at a time, if not the perf
tool will report device busy.
Best regards,
Junhao.
.task_ctx_nr = perf_sw_context,
.attr_groups = hisi_ptt_pmu_groups,
.event_init = hisi_ptt_pmu_event_init,
