-----Original Message----- From: John Garry john.garry@huawei.com Sent: 2021年1月19日 19:05 To: Joakim Zhang qiangqing.zhang@nxp.com; peterz@infradead.org; mingo@redhat.com; acme@kernel.org; mark.rutland@arm.com; alexander.shishkin@linux.intel.com; jolsa@redhat.com; namhyung@kernel.org; irogers@google.com; kjain@linux.ibm.com Cc: linux-kernel@vger.kernel.org; linuxarm@openeuler.org Subject: Re: [PATCH] perf metricgroup: Fix system PMU metrics
On 19/01/2021 10:56, Joakim Zhang wrote:
Joakim reports that getting "perf stat" for multiple system PMU metrics segfaults: ./perf stat -a -I 1000 -M imx8mm_ddr_write.all,imx8mm_ddr_write.all Segmentation fault
While the same works without issue for a single metric.
The logic in metricgroup__add_metric_sys_event_iter() is broken, in that add_metric() @m argument should be NULL for each new metric. Fix by not passing a holder for that, and rather make local in metricgroup__add_metric_sys_event_iter().
Fixes: be335ec28efa ("perf metricgroup: Support adding metrics for system PMUs") Reported-by: Joakim Zhangqiangqing.zhang@nxp.com Signed-off-by: John Garryjohn.garry@huawei.com
root@imx8mmevk:~# ./perf stat -a -I 1000 -M
imx8mm_ddr_read.all,imx8mm_ddr_write
.all# time counts unit events 1.001446500 40832
imx8mm_ddr.read_cycles # 638.0 KB imx8mm_ddr_read.all
1.001446500 16973imx8mm_ddr.write_cycles # 265.2 KB imx8mm_ddr_write.all
2.003150250 28836imx8mm_ddr.read_cycles # 450.6 KB imx8mm_ddr_read.all
2.003150250 6705imx8mm_ddr.write_cycles # 104.8 KB imx8mm_ddr_write.all
For this issue, Tested-by: Joakim Zhangqiangqing.zhang@nxp.com
Hi John,
It seems have other issue compared to 5.10 kernel after switching to this
framework, below metric can't work.
"MetricExpr": "(( imx8_ddr0@read\-cycles@ + imx8_ddr0@write\-cycles@ )
- 4 * 4 / duration_time) / (750 * 1000000 * 4 * 4)"
After change to: "MetricExpr": "(( imx8mm_ddr.read_cycles + imx8mm_ddr.write_cycles ) * 4 * 4 / duration_time) / (750 * 1000000 * 4 * 4)",
Hmmm... not sure what you mean by "compared to 5.10 kernel". As far as I'm concerned, none of this was supported in 5.10 and metrics did not work for arm64. Support for sys PMU events+metrics only came in 5.11-rc.
Yes, 5.10 doesn't support ARM64. I add some code let it work locally. And, "MetricExpr": "(( imx8_ddr0@read\-cycles@ + imx8_ddr0@write\-cycles@ ) * 4 * 4 / duration_time) / (750 * 1000000 * 4 * 4)" Above metric expression can work fine.
Anyway, can you share the full metric event which you say does not work, not just the "MetricExpr"?
OK, Could help check below metric? Thanks. "MetricExpr": "(( imx8_ddr0@read\-cycles@ + imx8_ddr0@write\-cycles@ ) * 4 * 4 / duration_time) / (750 * 1000000 * 4 * 4)" or "MetricExpr": "(( imx8mm_ddr.read_cycles + imx8mm_ddr.write_cycles ) * 4 * 4 / duration_time) / (750 * 1000000 * 4 * 4)"
Best Regards, Joakim Zhang
Thanks, John