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034f7ee130
Uncore becomes die-scope on Xeon Cascade Lake-AP and perf has supported
--per-die aggregation yet.
One issue is found in check_per_pkg() for uncore events running on AP
system. On cascade Lake-AP, we have:
S0-D0
S0-D1
S1-D0
S1-D1
But in check_per_pkg(), S0-D1 and S1-D1 are skipped because the mask
bits for S0 and S1 have been set for S0-D0 and S1-D0. It doesn't check
die_id. So the counting for S0-D1 and S1-D1 are set to zero. That's not
correct.
root@lkp-csl-2ap4 ~# ./perf stat -a -I 1000 -e llc_misses.mem_read --per-die -- sleep 5
1.001460963 S0-D0 1 1317376 Bytes llc_misses.mem_read
1.001460963 S0-D1 1 998016 Bytes llc_misses.mem_read
1.001460963 S1-D0 1 970496 Bytes llc_misses.mem_read
1.001460963 S1-D1 1 1291264 Bytes llc_misses.mem_read
2.003488021 S0-D0 1 1082048 Bytes llc_misses.mem_read
2.003488021 S0-D1 1 1919040 Bytes llc_misses.mem_read
2.003488021 S1-D0 1 890752 Bytes llc_misses.mem_read
2.003488021 S1-D1 1 2380800 Bytes llc_misses.mem_read
3.005613270 S0-D0 1 1126080 Bytes llc_misses.mem_read
3.005613270 S0-D1 1 2898176 Bytes llc_misses.mem_read
3.005613270 S1-D0 1 870912 Bytes llc_misses.mem_read
3.005613270 S1-D1 1 3388608 Bytes llc_misses.mem_read
4.007627598 S0-D0 1 1124608 Bytes llc_misses.mem_read
4.007627598 S0-D1 1 3884416 Bytes llc_misses.mem_read
4.007627598 S1-D0 1 921088 Bytes llc_misses.mem_read
4.007627598 S1-D1 1 4451840 Bytes llc_misses.mem_read
5.001479927 S0-D0 1 963328 Bytes llc_misses.mem_read
5.001479927 S0-D1 1 4831936 Bytes llc_misses.mem_read
5.001479927 S1-D0 1 895104 Bytes llc_misses.mem_read
5.001479927 S1-D1 1 5496640 Bytes llc_misses.mem_read
From above output, we can see S0-D1 and S1-D1 don't report the interval
values, they are continued to grow. That's because check_per_pkg()
wrongly decides to use zero counts for S0-D1 and S1-D1.
So in check_per_pkg(), we should use hashmap(socket,die) to decide if
the cpu counts needs to skip. Only considering socket is not enough.
Now with this patch,
root@lkp-csl-2ap4 ~# ./perf stat -a -I 1000 -e llc_misses.mem_read --per-die -- sleep 5
1.001586691 S0-D0 1 1229440 Bytes llc_misses.mem_read
1.001586691 S0-D1 1 976832 Bytes llc_misses.mem_read
1.001586691 S1-D0 1 938304 Bytes llc_misses.mem_read
1.001586691 S1-D1 1 1227328 Bytes llc_misses.mem_read
2.003776312 S0-D0 1 1586752 Bytes llc_misses.mem_read
2.003776312 S0-D1 1 875392 Bytes llc_misses.mem_read
2.003776312 S1-D0 1 855616 Bytes llc_misses.mem_read
2.003776312 S1-D1 1 949376 Bytes llc_misses.mem_read
3.006512788 S0-D0 1 1338880 Bytes llc_misses.mem_read
3.006512788 S0-D1 1 920064 Bytes llc_misses.mem_read
3.006512788 S1-D0 1 877184 Bytes llc_misses.mem_read
3.006512788 S1-D1 1 1020736 Bytes llc_misses.mem_read
4.008895291 S0-D0 1 926592 Bytes llc_misses.mem_read
4.008895291 S0-D1 1 906368 Bytes llc_misses.mem_read
4.008895291 S1-D0 1 892224 Bytes llc_misses.mem_read
4.008895291 S1-D1 1 987712 Bytes llc_misses.mem_read
5.001590993 S0-D0 1 962624 Bytes llc_misses.mem_read
5.001590993 S0-D1 1 912512 Bytes llc_misses.mem_read
5.001590993 S1-D0 1 891200 Bytes llc_misses.mem_read
5.001590993 S1-D1 1 978432 Bytes llc_misses.mem_read
On no-die system, die_id is 0, actually it's hashmap(socket,0), original behavior
is not changed.
Reported-by: Ying Huang <ying.huang@intel.com>
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Huang <ying.huang@intel.com>
Link: http://lore.kernel.org/lkml/20210128013417.25597-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
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Please read the Documentation/process/changes.rst file, as it contains the
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