From: Prasad Pandit <p...@fedoraproject.org>
Libaio defines IO_CMD_FDSYNC command to sync all outstanding
asynchronous I/O operations, by flushing out file data to the
disk storage.
Enable linux-aio to submit such aio request. This helps to
reduce latency induced via pthread_create calls by
thread-pool (aio=threads).
Signed-off-by: Prasad Pandit <p...@fedoraproject.org>
---
block/file-posix.c | 5 +++++
block/linux-aio.c | 5 ++++-
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/block/file-posix.c b/block/file-posix.c
index 35684f7e21..4ef6c6c9e5 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -2599,6 +2599,11 @@ static int coroutine_fn
raw_co_flush_to_disk(BlockDriverState *bs)
if (raw_check_linux_io_uring(s)) {
return luring_co_submit(bs, s->fd, 0, NULL, QEMU_AIO_FLUSH);
}
+#endif
+#ifdef CONFIG_LINUX_AIO
+ if (raw_check_linux_aio(s)) {
+ return laio_co_submit(s->fd, 0, NULL, QEMU_AIO_FLUSH, 0);
+ }
#endif
return raw_thread_pool_submit(handle_aiocb_flush, &acb);
}
diff --git a/block/linux-aio.c b/block/linux-aio.c
index ec05d946f3..d940d029e3 100644
--- a/block/linux-aio.c
+++ b/block/linux-aio.c
@@ -384,6 +384,9 @@ static int laio_do_submit(int fd, struct qemu_laiocb
*laiocb, off_t offset,
case QEMU_AIO_READ:
io_prep_preadv(iocbs, fd, qiov->iov, qiov->niov, offset);
break;
+ case QEMU_AIO_FLUSH:
+ io_prep_fdsync(iocbs, fd);
+ break;
/* Currently Linux kernel does not support other operations */
default:
fprintf(stderr, "%s: invalid AIO request type 0x%x.\n",
@@ -412,7 +415,7 @@ int coroutine_fn laio_co_submit(int fd, uint64_t offset,
QEMUIOVector *qiov,
AioContext *ctx = qemu_get_current_aio_context();
struct qemu_laiocb laiocb = {
.co = qemu_coroutine_self(),
- .nbytes = qiov->size,
+ .nbytes = qiov ? qiov->size : 0,
.ctx = aio_get_linux_aio(ctx),
.ret = -EINPROGRESS,
.is_read = (type == QEMU_AIO_READ),
--
2.44.0
