diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2020-04-08 10:11:39 +0100 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2020-04-09 15:55:06 +0100 |
| commit | 636b836d5f4e36ceebb788e2e0d4724f7f9406e1 (patch) | |
| tree | 93944141541d10969d8d4aba91068785271d2692 /util | |
| parent | 8bac3ba57eecc466b7e73dabf7d19328a59f684e (diff) | |
aio-posix: signal-proof fdmon-io_uring
The io_uring_enter(2) syscall returns with errno=EINTR when interrupted
by a signal. Retry the syscall in this case.
It's essential to do this in the io_uring_submit_and_wait() case. My
interpretation of the Linux v5.5 io_uring_enter(2) code is that it
shouldn't affect the io_uring_submit() case, but there is no guarantee
this will always be the case. Let's check for -EINTR around both APIs.
Note that the liburing APIs have -errno return values.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200408091139.273851-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'util')
| -rw-r--r-- | util/fdmon-io_uring.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/util/fdmon-io_uring.c b/util/fdmon-io_uring.c index b4d6109f20..d5a80ed6fb 100644 --- a/util/fdmon-io_uring.c +++ b/util/fdmon-io_uring.c @@ -88,7 +88,10 @@ static struct io_uring_sqe *get_sqe(AioContext *ctx) } /* No free sqes left, submit pending sqes first */ - ret = io_uring_submit(ring); + do { + ret = io_uring_submit(ring); + } while (ret == -EINTR); + assert(ret > 1); sqe = io_uring_get_sqe(ring); assert(sqe); @@ -282,7 +285,10 @@ static int fdmon_io_uring_wait(AioContext *ctx, AioHandlerList *ready_list, fill_sq_ring(ctx); - ret = io_uring_submit_and_wait(&ctx->fdmon_io_uring, wait_nr); + do { + ret = io_uring_submit_and_wait(&ctx->fdmon_io_uring, wait_nr); + } while (ret == -EINTR); + assert(ret >= 0); return process_cq_ring(ctx, ready_list); |