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author | Kevin Wolf <kwolf@redhat.com> | 2017-12-07 12:20:10 +0100 |
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committer | Kevin Wolf <kwolf@redhat.com> | 2017-12-22 15:05:31 +0100 |
commit | 7b6a3d35536f945c41aa62627cc295482606aa2e (patch) | |
tree | a563e0b74f85495d9124ecef92bd68383f226902 /block | |
parent | 9a7e86c8048cecededa665b1ca55c7f217ed358c (diff) | |
download | qemu-7b6a3d35536f945c41aa62627cc295482606aa2e.zip qemu-7b6a3d35536f945c41aa62627cc295482606aa2e.tar.gz qemu-7b6a3d35536f945c41aa62627cc295482606aa2e.tar.bz2 |
block: Make bdrv_drain() driver callbacks non-recursive
bdrv_drained_begin() doesn't increase bs->quiesce_counter recursively
and also doesn't notify other parent nodes of children, which both means
that the child nodes are not actually drained, and bdrv_drained_begin()
is providing useful functionality only on a single node.
To keep things consistent, we also shouldn't call the block driver
callbacks recursively.
A proper recursive drain version that provides an actually working
drained section for child nodes will be introduced later.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/io.c | 16 |
1 files changed, 9 insertions, 7 deletions
@@ -158,7 +158,7 @@ static void coroutine_fn bdrv_drain_invoke_entry(void *opaque) } /* Recursively call BlockDriver.bdrv_co_drain_begin/end callbacks */ -static void bdrv_drain_invoke(BlockDriverState *bs, bool begin) +static void bdrv_drain_invoke(BlockDriverState *bs, bool begin, bool recursive) { BdrvChild *child, *tmp; BdrvCoDrainData data = { .bs = bs, .done = false, .begin = begin}; @@ -172,8 +172,10 @@ static void bdrv_drain_invoke(BlockDriverState *bs, bool begin) bdrv_coroutine_enter(bs, data.co); BDRV_POLL_WHILE(bs, !data.done); - QLIST_FOREACH_SAFE(child, &bs->children, next, tmp) { - bdrv_drain_invoke(child->bs, begin); + if (recursive) { + QLIST_FOREACH_SAFE(child, &bs->children, next, tmp) { + bdrv_drain_invoke(child->bs, begin, true); + } } } @@ -265,7 +267,7 @@ void bdrv_drained_begin(BlockDriverState *bs) bdrv_parent_drained_begin(bs); } - bdrv_drain_invoke(bs, true); + bdrv_drain_invoke(bs, true, false); bdrv_drain_recurse(bs); } @@ -281,7 +283,7 @@ void bdrv_drained_end(BlockDriverState *bs) } /* Re-enable things in child-to-parent order */ - bdrv_drain_invoke(bs, false); + bdrv_drain_invoke(bs, false, false); bdrv_parent_drained_end(bs); aio_enable_external(bdrv_get_aio_context(bs)); } @@ -345,7 +347,7 @@ void bdrv_drain_all_begin(void) aio_context_acquire(aio_context); aio_disable_external(aio_context); bdrv_parent_drained_begin(bs); - bdrv_drain_invoke(bs, true); + bdrv_drain_invoke(bs, true, true); aio_context_release(aio_context); if (!g_slist_find(aio_ctxs, aio_context)) { @@ -388,7 +390,7 @@ void bdrv_drain_all_end(void) /* Re-enable things in child-to-parent order */ aio_context_acquire(aio_context); - bdrv_drain_invoke(bs, false); + bdrv_drain_invoke(bs, false, true); bdrv_parent_drained_end(bs); aio_enable_external(aio_context); aio_context_release(aio_context); |