> An experimental change to SelectorManager::shutdown unveiled a potential > deadlock between the SelectorManager thread trying to stop the > HttpClientImpl, and an executor thread concurrently trying to return a > connection to the pool. > > The issue seems to be caused by the ConnectionPool::returnToPool trying to > close the returned connection when stopping, while holding the ConnectionPool > state lock, and the SelectorManager thread trying to close a pooled > connection, holding the connection stateLock and trying to close the channel, > which caused the CleanupTrigger to fire and attempt to remove the connection > from the pool. > > This problem was observed once with the > java/net/httpclient/ThrowingSubscribersAsLimitingAsync.java test. > > To avoid the problem, the proposed fix is to wait until the > ConnectionPool::stateLock has been released before actually closing the > connection, and to wait until the PlainHttpConnection::stateLock has been > released before actually closing the channel. Indeed, there should be no need > to close those while holding the lock. > > This PR was recreated due to a bad merge pushed to > https://github.com/openjdk/jdk/pull/28421
Daniel Fuchs has updated the pull request incrementally with one additional commit since the last revision: More test updates ------------- Changes: - all: https://git.openjdk.org/jdk/pull/28430/files - new: https://git.openjdk.org/jdk/pull/28430/files/56643d23..5bbe9042 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=28430&range=06 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28430&range=05-06 Stats: 14 lines in 1 file changed: 12 ins; 0 del; 2 mod Patch: https://git.openjdk.org/jdk/pull/28430.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/28430/head:pull/28430 PR: https://git.openjdk.org/jdk/pull/28430
