Fix gradle-baseline excavator #6710
Conversation
| protected void noteFinished() { | ||
| state = State.COMPLETED; | ||
| condition.signalAll(); | ||
| lock.lock(); | ||
| try { | ||
| state = State.COMPLETED; | ||
| condition.signalAll(); | ||
| } finally { | ||
| lock.unlock(); | ||
| } | ||
| } |
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Alternatively I think we can annotate this method with @GuardedBy("lock") to ensure the lock is already held.
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good call and simplifies things
| } | ||
| if (executionException != null) { | ||
| throw new ExecutionException(executionException); | ||
| lock.lock(); |
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I suspect we can do the same here
| private Optional<ValueCacheSnapshot> getSnapshotForSequence(Sequence sequence) { | ||
| synchronized (this) { | ||
| return snapshotStore.getSnapshotForSequence(sequence); | ||
| } | ||
| } |
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could be refactored, but as written may make the synchronization more obvious. Either way works for me
| private Optional<ValueCacheSnapshot> getSnapshotForSequence(Sequence sequence) { | |
| synchronized (this) { | |
| return snapshotStore.getSnapshotForSequence(sequence); | |
| } | |
| } | |
| private synchronized Optional<ValueCacheSnapshot> getSnapshotForSequence(Sequence sequence) { | |
| return snapshotStore.getSnapshotForSequence(sequence); | |
| } |
| break; | ||
| default: | ||
| // Check for other control characters | ||
| if (c >= 0x0000 && c <= 0x001F) { |
| FinalSQLString cached = cachedKeyed.get(key); | ||
| FinalSQLString cached; | ||
| synchronized (cacheLock) { | ||
| cached = cachedKeyed.get(key); |
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It's not clear that this get invocation must occur holding cacheLock, but it's also not clear that the lock buys us anything on volatile reads/writes either, since only access and modify operations are locked without any state checks (the runWithCacheLock method appears unused internally).
Perhaps we can remove runWithCacheLock and drop the lock, relying on the volatile reference for ordering?
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The whole cachedKeyed/cacheLock here is a bit of a mess.
In a follow on PR after we unblock gradle-baseline, I do think we can probably remove runWithCacheLock (and possibly the whole cachedKeyed, cacheLock, setCachedKeyed, getCachedKeyed) as I don't see any consumers of these APIs.
Note that just removing the synchronized (cacheLock) from the volatile read still triggers the GuardedBy error (as expected), so I refactored into a separate method to explicitly do volatile read & suppress (also handle possible NPE).
error: [GuardedBy] This access should be guarded by 'SQLString.cacheLock', which is not currently held
FinalSQLString cached = cachedKeyed.get(key);
General
Before this PR:
gradle-baseline excavator PR #6470 is broken
After this PR:
==COMMIT_MSG==
Fix gradle-baseline excavator
==COMMIT_MSG==
Priority:
Concerns / possible downsides (what feedback would you like?):
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Does this PR create any API breaks (e.g. at the Java or HTTP layers) - if so, do we have compatibility?:
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Please tag any other people who should be aware of this PR:
@jeremyk-91
@sverma30
@raiju