Commit 0d83708a authored by Kevin Wolf's avatar Kevin Wolf
Browse files

block: Move recursion to bdrv_set_aio_context() 



Instead of having two recursions, in bdrv_attach_aio_context() and in
bdrv_detach_aio_context(), just having one recursion is enough. Said
functions are only about a single node now.

It is important that the recursion doesn't happen between detaching and
attaching a context to the current node because the nested call will
drain the node, and draining with a NULL context would segfault.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent a3a683c3

block.c

+7 −8
Original line number Diff line number Diff line
@@ -5679,7 +5679,6 @@ static void bdrv_do_remove_aio_context_notifier(BdrvAioNotifier *ban) 
static void bdrv_detach_aio_context(BlockDriverState *bs)

{

    BdrvAioNotifier *baf, *baf_tmp;

    BdrvChild *child;



    assert(!bs->walking_aio_notifiers);

    bs->walking_aio_notifiers = true;
@@ -5698,9 +5697,6 @@ static void bdrv_detach_aio_context(BlockDriverState *bs) 
    if (bs->drv && bs->drv->bdrv_detach_aio_context) {

        bs->drv->bdrv_detach_aio_context(bs);

    }

    QLIST_FOREACH(child, &bs->children, next) {

        bdrv_detach_aio_context(child->bs);

    }



    if (bs->quiesce_counter) {

        aio_enable_external(bs->aio_context);
@@ -5712,7 +5708,6 @@ static void bdrv_attach_aio_context(BlockDriverState *bs, 
                                    AioContext *new_context)

{

    BdrvAioNotifier *ban, *ban_tmp;

    BdrvChild *child;



    if (bs->quiesce_counter) {

        aio_disable_external(new_context);
@@ -5720,9 +5715,6 @@ static void bdrv_attach_aio_context(BlockDriverState *bs, 


    bs->aio_context = new_context;



    QLIST_FOREACH(child, &bs->children, next) {

        bdrv_attach_aio_context(child->bs, new_context);

    }

    if (bs->drv && bs->drv->bdrv_attach_aio_context) {

        bs->drv->bdrv_attach_aio_context(bs, new_context);

    }
@@ -5744,11 +5736,18 @@ static void bdrv_attach_aio_context(BlockDriverState *bs, 
 * the same as the current context of bs). */

void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context)

{

    BdrvChild *child;



    if (bdrv_get_aio_context(bs) == new_context) {

        return;

    }



    bdrv_drained_begin(bs);



    QLIST_FOREACH(child, &bs->children, next) {

        bdrv_set_aio_context(child->bs, new_context);

    }



    bdrv_detach_aio_context(bs);



    /* This function executes in the old AioContext so acquire the new one in