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Diffstat (limited to 'block/linux-aio.c')
-rw-r--r--block/linux-aio.c96
1 files changed, 94 insertions, 2 deletions
diff --git a/block/linux-aio.c b/block/linux-aio.c
index f0a2c08..4867369 100644
--- a/block/linux-aio.c
+++ b/block/linux-aio.c
@@ -25,6 +25,8 @@
*/
#define MAX_EVENTS 128
+#define MAX_QUEUED_IO 128
+
struct qemu_laiocb {
BlockDriverAIOCB common;
struct qemu_laio_state *ctx;
@@ -36,9 +38,19 @@ struct qemu_laiocb {
QLIST_ENTRY(qemu_laiocb) node;
};
+typedef struct {
+ struct iocb *iocbs[MAX_QUEUED_IO];
+ int plugged;
+ unsigned int size;
+ unsigned int idx;
+} LaioQueue;
+
struct qemu_laio_state {
io_context_t ctx;
EventNotifier e;
+
+ /* io queue for submit at batch */
+ LaioQueue io_q;
};
static inline ssize_t io_event_ret(struct io_event *ev)
@@ -135,6 +147,79 @@ static const AIOCBInfo laio_aiocb_info = {
.cancel = laio_cancel,
};
+static void ioq_init(LaioQueue *io_q)
+{
+ io_q->size = MAX_QUEUED_IO;
+ io_q->idx = 0;
+ io_q->plugged = 0;
+}
+
+static int ioq_submit(struct qemu_laio_state *s)
+{
+ int ret, i = 0;
+ int len = s->io_q.idx;
+
+ do {
+ ret = io_submit(s->ctx, len, s->io_q.iocbs);
+ } while (i++ < 3 && ret == -EAGAIN);
+
+ /* empty io queue */
+ s->io_q.idx = 0;
+
+ if (ret < 0) {
+ i = 0;
+ } else {
+ i = ret;
+ }
+
+ for (; i < len; i++) {
+ struct qemu_laiocb *laiocb =
+ container_of(s->io_q.iocbs[i], struct qemu_laiocb, iocb);
+
+ laiocb->ret = (ret < 0) ? ret : -EIO;
+ qemu_laio_process_completion(s, laiocb);
+ }
+ return ret;
+}
+
+static void ioq_enqueue(struct qemu_laio_state *s, struct iocb *iocb)
+{
+ unsigned int idx = s->io_q.idx;
+
+ s->io_q.iocbs[idx++] = iocb;
+ s->io_q.idx = idx;
+
+ /* submit immediately if queue is full */
+ if (idx == s->io_q.size) {
+ ioq_submit(s);
+ }
+}
+
+void laio_io_plug(BlockDriverState *bs, void *aio_ctx)
+{
+ struct qemu_laio_state *s = aio_ctx;
+
+ s->io_q.plugged++;
+}
+
+int laio_io_unplug(BlockDriverState *bs, void *aio_ctx, bool unplug)
+{
+ struct qemu_laio_state *s = aio_ctx;
+ int ret = 0;
+
+ assert(s->io_q.plugged > 0 || !unplug);
+
+ if (unplug && --s->io_q.plugged > 0) {
+ return 0;
+ }
+
+ if (s->io_q.idx > 0) {
+ ret = ioq_submit(s);
+ }
+
+ return ret;
+}
+
BlockDriverAIOCB *laio_submit(BlockDriverState *bs, void *aio_ctx, int fd,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque, int type)
@@ -168,8 +253,13 @@ BlockDriverAIOCB *laio_submit(BlockDriverState *bs, void *aio_ctx, int fd,
}
io_set_eventfd(&laiocb->iocb, event_notifier_get_fd(&s->e));
- if (io_submit(s->ctx, 1, &iocbs) < 0)
- goto out_free_aiocb;
+ if (!s->io_q.plugged) {
+ if (io_submit(s->ctx, 1, &iocbs) < 0) {
+ goto out_free_aiocb;
+ }
+ } else {
+ ioq_enqueue(s, iocbs);
+ }
return &laiocb->common;
out_free_aiocb:
@@ -204,6 +294,8 @@ void *laio_init(void)
goto out_close_efd;
}
+ ioq_init(&s->io_q);
+
return s;
out_close_efd: