From fc24908e7d232b79c2a6f0363f52bda18dedb57b Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 29 Nov 2017 11:25:13 +0100 Subject: blockjob: reimplement block_job_sleep_ns to allow cancellation This reverts the effects of commit 4afeffc857 ("blockjob: do not allow coroutine double entry or entry-after-completion", 2017-11-21) This fixed the symptom of a bug rather than the root cause. Canceling the wait on a sleeping blockjob coroutine is generally fine, we just need to make it work correctly across AioContexts. To do so, use a QEMUTimer that calls block_job_enter. Use a mutex to ensure that block_job_enter synchronizes correctly with block_job_sleep_ns. Signed-off-by: Paolo Bonzini Tested-By: Jeff Cody Reviewed-by: Fam Zheng Reviewed-by: Stefan Hajnoczi Reviewed-by: Jeff Cody Signed-off-by: Kevin Wolf --- include/block/blockjob.h | 8 +++++++- include/block/blockjob_int.h | 4 ++-- 2 files changed, 9 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/block/blockjob.h b/include/block/blockjob.h index 67c0968..00403d9 100644 --- a/include/block/blockjob.h +++ b/include/block/blockjob.h @@ -77,7 +77,7 @@ typedef struct BlockJob { /** * Set to false by the job while the coroutine has yielded and may be * re-entered by block_job_enter(). There may still be I/O or event loop - * activity pending. + * activity pending. Accessed under block_job_mutex (in blockjob.c). */ bool busy; @@ -135,6 +135,12 @@ typedef struct BlockJob { */ int ret; + /** + * Timer that is used by @block_job_sleep_ns. Accessed under + * block_job_mutex (in blockjob.c). + */ + QEMUTimer sleep_timer; + /** Non-NULL if this job is part of a transaction */ BlockJobTxn *txn; QLIST_ENTRY(BlockJob) txn_list; diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h index f7ab183..c9b23b0 100644 --- a/include/block/blockjob_int.h +++ b/include/block/blockjob_int.h @@ -142,8 +142,8 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, * @ns: How many nanoseconds to stop for. * * Put the job to sleep (assuming that it wasn't canceled) for @ns - * %QEMU_CLOCK_REALTIME nanoseconds. Canceling the job will not interrupt - * the wait, so the cancel will not process until the coroutine wakes up. + * %QEMU_CLOCK_REALTIME nanoseconds. Canceling the job will immediately + * interrupt the wait. */ void block_job_sleep_ns(BlockJob *job, int64_t ns); -- cgit v1.1