[XPTI][INFRA] Fixes race issues with Emhash under contention #19600
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tovinkere
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Jul 25, 2025
tovinkere
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- Under severe concurrent access, rehash in Emhash was being called during insert and this is documented as a problem in Emhash Readme. Rehash for the Emhash containers will not have to be called now as enough space for handling streams is reserved.
- xptiCheckTraceEnabled() is now thread-safe
- Emhash containers now have sizes reserved to accommodate the entries and all second level hash maps that were Emhash in the past have been replaced with parallel hashmap.
- xptiCheckTraceEnabled() is now thread-safe - Emash can have issues when rehash is called during insertion. So, all Emhash containers now have sizes reserved to accommodate the entries and all second level hash maps use parallel hashmap. - Under severe concurrent access, rehash in Emhash was being called during insert. Rehash for the Emhash containers will not have to be called now. Signed-off-by: Vasanth Tovinkere <[email protected]>
Signed-off-by: Vasanth Tovinkere <[email protected]>
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Looks reasonable, but I'm not familiar with the code. @KseniyaTikhomirova , FYI, maybe for a post-commit review?
xptifw/src/xpti_trace_framework.cpp
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| #endif | ||
| { | ||
| std::unique_lock<std::shared_mutex> Lock(MFlagsLock); | ||
| auto &TraceFlags = MStreamFlags[StreamID]; // Get the trace flags for the |
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Signed-off-by: Vasanth Tovinkere <[email protected]>
aelovikov-intel
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Jul 25, 2025
sarnex
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Jul 25, 2025
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sarnex
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lgtm from dependency pov, parallel hashmap is already a dep so this isnt changing anything. not qualified to review for correctness
Signed-off-by: Vasanth Tovinkere <[email protected]>
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Fail seems to be covered by #15207. |
AlexeySachkov
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Oct 13, 2025
…9600) - Under severe concurrent access, rehash in Emhash was being called during insert and this is documented as a problem in Emhash Readme. Rehash for the Emhash containers will not have to be called now as enough space for handling streams is reserved. - xptiCheckTraceEnabled() is now thread-safe - Emhash containers now have sizes reserved to accommodate the entries and all second level hash maps that were Emhash in the past have been replaced with parallel hashmap. --------- Signed-off-by: Vasanth Tovinkere <[email protected]>
AlexeySachkov
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Oct 15, 2025
This is a cherry-pick of #19600 - Under severe concurrent access, rehash in Emhash was being called during insert and this is documented as a problem in Emhash Readme. Rehash for the Emhash containers will not have to be called now as enough space for handling streams is reserved. - xptiCheckTraceEnabled() is now thread-safe - Emhash containers now have sizes reserved to accommodate the entries and all second level hash maps that were Emhash in the past have been replaced with parallel hashmap. Patch-by: Vasanth Tovinkere <[email protected]>
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