dyn-metrics-store: fix race on StatsCounter use_count#858
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MrAnno merged 4 commits intoaxoflow:mainfrom Nov 26, 2025
Merged
dyn-metrics-store: fix race on StatsCounter use_count#858MrAnno merged 4 commits intoaxoflow:mainfrom
MrAnno merged 4 commits intoaxoflow:mainfrom
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`use_count` is a non-atomic integer. Modifying it from parallel threads at the same time is racy. Both `merge()` and `retrieve_counter()` increases the `use_count` of a counter. - `merge()` is called with the `global_metrics_cache_lock` held - `retrieve_counter()` calls `stats_lock()` inside If `merge()` is being called in one thread (thread deinit) and `retrieve_counter()` is being called in another (new counter for the TLS cache), they can run in the same time, incrementing `use_count` in a racy manner. Signed-off-by: Attila Szakacs <[email protected]>
Signed-off-by: Attila Szakacs <[email protected]>
Signed-off-by: Attila Szakacs <[email protected]>
Signed-off-by: Attila Szakacs <[email protected]>
MrAnno
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Nov 26, 2025
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use_countis a non-atomic integer.Modifying it from parallel threads at the same time is racy.
Both
merge()andretrieve_counter()increases theuse_countof a counter.merge()is called with theglobal_metrics_cache_lockheldretrieve_counter()callsstats_lock()insideThese are two different locks, and don't block each other.
If
merge()is being called in one thread (thread deinit) andretrieve_counter()is being called in another (new counter for the TLS cache), they can run in the same time, incrementinguse_countin a racy manner.