From: "Maciej S. Szmigiero" <[email protected]>
thread_pool_adjust_max_threads_to_work() is supposed to give each task its
own thread by setting the pool max thread count limit accordingly.
However, if there aren't any tasks currently in the pool the pool max
thread count will be set to 0, which will trigger an assertion failure
in thread_pool_set_max_threads() - because setting this value would
completely block the pool by not allowing it to process any submitted
tasks.
This also can happen if a task is submitted via
thread_pool_submit_immediate() to an empty pool but the task completes so
quickly that by the time this function calls
thread_pool_adjust_max_threads_to_work() the pool again has no unfinished
tasks in it.
Fix this by making sure that the pool is allowed to create at least 1
thread.
Fixes: b5aa74968b27 ("thread-pool: Implement generic (non-AIO) pool support")
Signed-off-by: Maciej S. Szmigiero <[email protected]>
---
util/thread-pool.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/util/thread-pool.c b/util/thread-pool.c
index 8f8cb38d5ce0..4e75191c983e 100644
--- a/util/thread-pool.c
+++ b/util/thread-pool.c
@@ -493,5 +493,5 @@ bool thread_pool_adjust_max_threads_to_work(ThreadPool
*pool)
{
QEMU_LOCK_GUARD(&pool->cur_work_lock);
- return thread_pool_set_max_threads(pool, pool->cur_work);
+ return thread_pool_set_max_threads(pool, MAX(pool->cur_work, 1));
}
