diff options
author | Ian Rogers <[email protected]> | 2023-12-06 17:16:53 -0800 |
---|---|---|
committer | Arnaldo Carvalho de Melo <[email protected]> | 2023-12-20 14:56:10 -0300 |
commit | e77b0236cd0cd1572c6a9b25097b207eab799e74 (patch) | |
tree | f5a696d86e7d54804b39f6b817559549ee1545f1 | |
parent | 9084952704ba075de28684301ec282b6626b5e7a (diff) |
perf maps: Add maps__load_first()
Avoid bpf_lock_contention_read touching the internal maps data structure
by adding a helper function. As access is done directly on the map in
maps, hold the read lock to stop it being removed.
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Changbin Du <[email protected]>
Cc: Colin Ian King <[email protected]>
Cc: Dmitrii Dolgov <[email protected]>
Cc: German Gomez <[email protected]>
Cc: Guilherme Amadio <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: K Prateek Nayak <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Li Dong <[email protected]>
Cc: Liam Howlett <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Ming Wang <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Nick Terrell <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Sandipan Das <[email protected]>
Cc: Sean Christopherson <[email protected]>
Cc: Steinar H. Gunderson <[email protected]>
Cc: Vincent Whitchurch <[email protected]>
Cc: Wenyu Liu <[email protected]>
Cc: Yang Jihong <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
-rw-r--r-- | tools/perf/util/bpf_lock_contention.c | 2 | ||||
-rw-r--r-- | tools/perf/util/maps.c | 13 | ||||
-rw-r--r-- | tools/perf/util/maps.h | 2 |
3 files changed, 16 insertions, 1 deletions
diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c index f1716c089c99..31ff19afc20c 100644 --- a/tools/perf/util/bpf_lock_contention.c +++ b/tools/perf/util/bpf_lock_contention.c @@ -318,7 +318,7 @@ int lock_contention_read(struct lock_contention *con) } /* make sure it loads the kernel map */ - map__load(maps__first(machine->kmaps)->map); + maps__load_first(machine->kmaps); prev_key = NULL; while (!bpf_map_get_next_key(fd, prev_key, &key)) { diff --git a/tools/perf/util/maps.c b/tools/perf/util/maps.c index 986daa1b0497..024a6c9f72c4 100644 --- a/tools/perf/util/maps.c +++ b/tools/perf/util/maps.c @@ -793,3 +793,16 @@ out: } return err; } + +void maps__load_first(struct maps *maps) +{ + struct map_rb_node *first; + + down_read(maps__lock(maps)); + + first = maps__first(maps); + if (first) + map__load(first->map); + + up_read(maps__lock(maps)); +} diff --git a/tools/perf/util/maps.h b/tools/perf/util/maps.h index e4a49d6ff5cf..b7ab3ec61b7c 100644 --- a/tools/perf/util/maps.h +++ b/tools/perf/util/maps.h @@ -142,4 +142,6 @@ void __maps__sort_by_name(struct maps *maps); void maps__fixup_end(struct maps *maps); +void maps__load_first(struct maps *maps); + #endif // __PERF_MAPS_H |