diff options
Diffstat (limited to 'src/third_party/wiredtiger/src/support/cond_auto.c')
| -rw-r--r-- | src/third_party/wiredtiger/src/support/cond_auto.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/src/third_party/wiredtiger/src/support/cond_auto.c b/src/third_party/wiredtiger/src/support/cond_auto.c index f07cf2fd2a7..c5a43e6d67c 100644 --- a/src/third_party/wiredtiger/src/support/cond_auto.c +++ b/src/third_party/wiredtiger/src/support/cond_auto.c @@ -42,7 +42,7 @@ void __wt_cond_auto_wait_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond, bool progress, bool (*run_func)(WT_SESSION_IMPL *), bool *signalled) { - uint64_t delta; + uint64_t delta, saved_prev_wait; /* * Catch cases where this function is called with a condition variable that wasn't initialized @@ -55,7 +55,15 @@ __wt_cond_auto_wait_signal(WT_SESSION_IMPL *session, WT_CONDVAR *cond, bool prog cond->prev_wait = cond->min_wait; else { delta = WT_MAX(1, (cond->max_wait - cond->min_wait) / 10); - cond->prev_wait = WT_MIN(cond->max_wait, cond->prev_wait + delta); + /* + * Try to update the previous wait value for the condition variable. There can be multiple + * threads doing this concurrently, so use atomic operations to make sure the value remains + * within the bounds of the maximum configured. Don't retry if our update didn't make it in + * - it's not necessary for the previous wait time to be updated every time. + */ + WT_ORDERED_READ(saved_prev_wait, cond->prev_wait); + __wt_atomic_cas64( + &cond->prev_wait, saved_prev_wait, WT_MIN(cond->max_wait, saved_prev_wait + delta)); } __wt_cond_wait_signal(session, cond, cond->prev_wait, run_func, signalled); |