Accept EINTR (interrupted by signal) futex return code (#10517)
This loop is already handling EAGAIN. It looks like it should handle
EINTR the same way.
I'm trying to guess what might cause the intermittent crash #10337. One
thing that would explain it is if the iree_task_scope_wait_idle done at
the end of SubmitTasksAndWaitIdle wasn't doing its job. It calls
iree_notification_await, which assumes that
iree_notification_commit_wait never returns false unless the deadline is
exceeded. But iree_notification_commit_wait does return false if the
futex syscall returns an expected error code, so we need to handle the
exhaustive list of return codes that might come out of this syscall. The
manual page lists only very few possible return codes for the particular
FUTEX_WAIT op we're doing here (there are plenty of error cases, but few
apply to FUTEX_WAIT). EINTR is the only one that I could see us missing
here.
diff --git a/runtime/src/iree/base/internal/synchronization.c b/runtime/src/iree/base/internal/synchronization.c
index ac0a9d9..ccb42a4 100644
--- a/runtime/src/iree/base/internal/synchronization.c
+++ b/runtime/src/iree/base/internal/synchronization.c
@@ -178,7 +178,7 @@
int rc = syscall(
SYS_futex, address, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, expected_value,
timeout_ms == IREE_INFINITE_TIMEOUT_MS ? NULL : &timeout, NULL, 0);
- if (IREE_LIKELY(rc == 0) || errno == EAGAIN) {
+ if (IREE_LIKELY(rc == 0) || errno == EAGAIN || errno == EINTR) {
return IREE_STATUS_OK;
} else if (errno == ETIMEDOUT) {
return IREE_STATUS_DEADLINE_EXCEEDED;
