block: block: introduce APIs for submitting IO as a batch

This patch introduces three APIs so that following
patches can support queuing I/O requests and submitting them
as a batch for improving I/O performance.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Ming Lei 2014-07-04 18:04:33 +08:00 committed by Stefan Hajnoczi
parent 5a18e67dfd
commit 448ad91db4
3 changed files with 40 additions and 0 deletions

31
block.c
View File

@ -1905,6 +1905,7 @@ void bdrv_drain_all(void)
bool bs_busy;
aio_context_acquire(aio_context);
bdrv_flush_io_queue(bs);
bdrv_start_throttled_reqs(bs);
bs_busy = bdrv_requests_pending(bs);
bs_busy |= aio_poll(aio_context, bs_busy);
@ -5782,3 +5783,33 @@ BlockDriverState *check_to_replace_node(const char *node_name, Error **errp)
return to_replace_bs;
}
void bdrv_io_plug(BlockDriverState *bs)
{
BlockDriver *drv = bs->drv;
if (drv && drv->bdrv_io_plug) {
drv->bdrv_io_plug(bs);
} else if (bs->file) {
bdrv_io_plug(bs->file);
}
}
void bdrv_io_unplug(BlockDriverState *bs)
{
BlockDriver *drv = bs->drv;
if (drv && drv->bdrv_io_unplug) {
drv->bdrv_io_unplug(bs);
} else if (bs->file) {
bdrv_io_unplug(bs->file);
}
}
void bdrv_flush_io_queue(BlockDriverState *bs)
{
BlockDriver *drv = bs->drv;
if (drv && drv->bdrv_flush_io_queue) {
drv->bdrv_flush_io_queue(bs);
} else if (bs->file) {
bdrv_flush_io_queue(bs->file);
}
}

View File

@ -584,4 +584,8 @@ AioContext *bdrv_get_aio_context(BlockDriverState *bs);
*/
void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context);
void bdrv_io_plug(BlockDriverState *bs);
void bdrv_io_unplug(BlockDriverState *bs);
void bdrv_flush_io_queue(BlockDriverState *bs);
#endif

View File

@ -261,6 +261,11 @@ struct BlockDriver {
void (*bdrv_attach_aio_context)(BlockDriverState *bs,
AioContext *new_context);
/* io queue for linux-aio */
void (*bdrv_io_plug)(BlockDriverState *bs);
void (*bdrv_io_unplug)(BlockDriverState *bs);
void (*bdrv_flush_io_queue)(BlockDriverState *bs);
QLIST_ENTRY(BlockDriver) list;
};