| Message ID | 20230203021324.143540-1-namhyung@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | perf lock contention: Improve aggr x filter combination | expand |
Em Thu, Feb 02, 2023 at 06:13:21PM -0800, Namhyung Kim escreveu: > Hello, > > The callstack filter can be useful to debug lock issues but it has a > limitation that it only works with caller aggregation mode (which is the > default setting). IOW it cannot filter by callstack when showing tasks > or lock addresses/names. Thanks, applied. - Arnaldo > But sometimes users want to use the filter for other aggregation mode. > Like "show me lock addresses/names from this caller only" or "show me > tasks having these callers". > > When it's using tracepoint events from the data file, the situation is > good since the tracepoints have all the necessary info. But when using > BPF it needs to extend the key of lock stat BPF map to have more than > one info like 'pid + stack_id' or 'lock_addr + stack_id'. As callstack > filter works in userspace, it should save the both info. > > With this change we can now use the -S/--callstack-filter with the > -t/--threads option or -l/--lock-addr option. It's also possible to use > it with other filter options. > > The following example shows the top 5 tasks that have contention > somewhere in the epoll handling. > > $ sudo perf lock con -abt -S epoll -E5 -- sleep 1 > contended total wait max wait avg wait pid comm > > 2 58.64 us 32.38 us 29.32 us 1514752 Chrome_IOThread > 3 29.31 us 12.65 us 9.77 us 3773 Xorg > 1 17.45 us 17.45 us 17.45 us 1514906 Chrome_ChildIOT > 1 15.41 us 15.41 us 15.41 us 1515382 Chrome_ChildIOT > 1 12.52 us 12.52 us 12.52 us 293878 IPC I/O Parent > > You get get the code at 'perf/lock-filter-v1' branch in > > git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git > > Thanks, > Namhyung > > Namhyung Kim (3): > perf lock contention: Factor out lock_contention_get_name() > perf lock contention: Use lock_stat_find{,new} > perf lock contention: Support filters for different aggregation > > tools/perf/builtin-lock.c | 79 ++++---- > tools/perf/util/Build | 5 +- > tools/perf/util/bpf_lock_contention.c | 180 +++++++++++------- > .../perf/util/bpf_skel/lock_contention.bpf.c | 15 +- > tools/perf/util/bpf_skel/lock_data.h | 4 +- > tools/perf/util/lock-contention.h | 5 + > 6 files changed, 178 insertions(+), 110 deletions(-) > > -- > 2.39.1.519.gcb327c4b5f-goog >
Hello, The callstack filter can be useful to debug lock issues but it has a limitation that it only works with caller aggregation mode (which is the default setting). IOW it cannot filter by callstack when showing tasks or lock addresses/names. But sometimes users want to use the filter for other aggregation mode. Like "show me lock addresses/names from this caller only" or "show me tasks having these callers". When it's using tracepoint events from the data file, the situation is good since the tracepoints have all the necessary info. But when using BPF it needs to extend the key of lock stat BPF map to have more than one info like 'pid + stack_id' or 'lock_addr + stack_id'. As callstack filter works in userspace, it should save the both info. With this change we can now use the -S/--callstack-filter with the -t/--threads option or -l/--lock-addr option. It's also possible to use it with other filter options. The following example shows the top 5 tasks that have contention somewhere in the epoll handling. $ sudo perf lock con -abt -S epoll -E5 -- sleep 1 contended total wait max wait avg wait pid comm 2 58.64 us 32.38 us 29.32 us 1514752 Chrome_IOThread 3 29.31 us 12.65 us 9.77 us 3773 Xorg 1 17.45 us 17.45 us 17.45 us 1514906 Chrome_ChildIOT 1 15.41 us 15.41 us 15.41 us 1515382 Chrome_ChildIOT 1 12.52 us 12.52 us 12.52 us 293878 IPC I/O Parent You get get the code at 'perf/lock-filter-v1' branch in git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git Thanks, Namhyung Namhyung Kim (3): perf lock contention: Factor out lock_contention_get_name() perf lock contention: Use lock_stat_find{,new} perf lock contention: Support filters for different aggregation tools/perf/builtin-lock.c | 79 ++++---- tools/perf/util/Build | 5 +- tools/perf/util/bpf_lock_contention.c | 180 +++++++++++------- .../perf/util/bpf_skel/lock_contention.bpf.c | 15 +- tools/perf/util/bpf_skel/lock_data.h | 4 +- tools/perf/util/lock-contention.h | 5 + 6 files changed, 178 insertions(+), 110 deletions(-)