block: remove AioContext locking

This is the big patch that removes
aio_context_acquire()/aio_context_release() from the block layer and
affected block layer users.

There isn't a clean way to split this patch and the reviewers are likely
the same group of people, so I decided to do it in one patch.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-ID: <20231205182011.1976568-7-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2023-12-05 13:20:03 -05:00 committed by Kevin Wolf
parent 6bc30f1949
commit b49f4755c7
41 changed files with 104 additions and 1169 deletions

View file

@ -260,8 +260,6 @@ static void xen_block_complete_aio(void *opaque, int ret)
XenBlockRequest *request = opaque;
XenBlockDataPlane *dataplane = request->dataplane;
aio_context_acquire(dataplane->ctx);
if (ret != 0) {
error_report("%s I/O error",
request->req.operation == BLKIF_OP_READ ?
@ -273,10 +271,10 @@ static void xen_block_complete_aio(void *opaque, int ret)
if (request->presync) {
request->presync = 0;
xen_block_do_aio(request);
goto done;
return;
}
if (request->aio_inflight > 0) {
goto done;
return;
}
switch (request->req.operation) {
@ -318,9 +316,6 @@ static void xen_block_complete_aio(void *opaque, int ret)
if (dataplane->more_work) {
qemu_bh_schedule(dataplane->bh);
}
done:
aio_context_release(dataplane->ctx);
}
static bool xen_block_split_discard(XenBlockRequest *request,
@ -601,9 +596,7 @@ static void xen_block_dataplane_bh(void *opaque)
{
XenBlockDataPlane *dataplane = opaque;
aio_context_acquire(dataplane->ctx);
xen_block_handle_requests(dataplane);
aio_context_release(dataplane->ctx);
}
static bool xen_block_dataplane_event(void *opaque)
@ -703,10 +696,8 @@ void xen_block_dataplane_stop(XenBlockDataPlane *dataplane)
xen_block_dataplane_detach(dataplane);
}
aio_context_acquire(dataplane->ctx);
/* Xen doesn't have multiple users for nodes, so this can't fail */
blk_set_aio_context(dataplane->blk, qemu_get_aio_context(), &error_abort);
aio_context_release(dataplane->ctx);
/*
* Now that the context has been moved onto the main thread, cancel
@ -752,7 +743,6 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
{
ERRP_GUARD();
XenDevice *xendev = dataplane->xendev;
AioContext *old_context;
unsigned int ring_size;
unsigned int i;
@ -836,11 +826,8 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
goto stop;
}
old_context = blk_get_aio_context(dataplane->blk);
aio_context_acquire(old_context);
/* If other users keep the BlockBackend in the iothread, that's ok */
blk_set_aio_context(dataplane->blk, dataplane->ctx, NULL);
aio_context_release(old_context);
if (!blk_in_drain(dataplane->blk)) {
xen_block_dataplane_attach(dataplane);