diff options
author | Peter Zijlstra <peterz@infradead.org> | 2022-09-02 18:48:55 +0200 |
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committer | Peter Zijlstra <peterz@infradead.org> | 2022-09-07 21:54:01 +0200 |
commit | f3c0eba287049237b23d1300376768293eb89e69 (patch) | |
tree | ceb5cab8cd9b1733b4504a639a63454c4d4c746c /kernel/events | |
parent | 88081cfb699ce2568e5309c145eb9f9e9497b53f (diff) | |
download | linux-f3c0eba287049237b23d1300376768293eb89e69.tar.gz |
perf: Add a few assertions
While auditing 6b959ba22d34 ("perf/core: Fix reentry problem in perf_output_read_group()") a few spots were found that wanted assertions. Notable for_each_sibling_event() relies on exclusion from modification. This would normally be holding either ctx->lock or ctx->mutex, however due to how things are constructed disabling IRQs is a valid and sufficient substitute for ctx->lock. Another possible site to add assertions would be the various pmu::{add,del,read,..}() methods, but that's not trivially expressable in C -- the best option is wrappers, but those are easy enough to forget. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Diffstat (limited to 'kernel/events')
-rw-r--r-- | kernel/events/core.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 00389d5f9241..3e90e454b995 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1468,6 +1468,8 @@ static void __update_context_time(struct perf_event_context *ctx, bool adv) { u64 now = perf_clock(); + lockdep_assert_held(&ctx->lock); + if (adv) ctx->time += now - ctx->timestamp; ctx->timestamp = now; |