diff options
author | Michael S. Tsirkin <mst@redhat.com> | 2016-04-06 12:16:26 +0200 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2016-04-07 19:57:33 +0300 |
commit | 8a2fad57eb124ec0633f6f2b1c74c991fc7501bd (patch) | |
tree | ba4c029404ecda2c751b1d4a886a67a9d8b58bd9 /hw | |
parent | 344dc16fae0cb6a011aa5befffc8e7d520b11d5d (diff) |
virtio-blk: use aio handler for data plane
In addition to handling IO in vcpu thread and in io thread, dataplane
introduces yet another mode: handling it by AioContext.
This reuses the same handler as previous modes, which triggers races as
these were not designed to be reentrant. Use a separate handler just
for aio, and disable regular handlers when dataplane is active.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw')
-rw-r--r-- | hw/block/dataplane/virtio-blk.c | 13 | ||||
-rw-r--r-- | hw/block/virtio-blk.c | 27 |
2 files changed, 30 insertions, 10 deletions
diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c index 2870d21a70..65c7f7041d 100644 --- a/hw/block/dataplane/virtio-blk.c +++ b/hw/block/dataplane/virtio-blk.c @@ -184,6 +184,17 @@ void virtio_blk_data_plane_destroy(VirtIOBlockDataPlane *s) g_free(s); } +static void virtio_blk_data_plane_handle_output(VirtIODevice *vdev, + VirtQueue *vq) +{ + VirtIOBlock *s = (VirtIOBlock *)vdev; + + assert(s->dataplane); + assert(s->dataplane_started); + + virtio_blk_handle_vq(s, vq); +} + /* Context: QEMU global mutex held */ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s) { @@ -226,6 +237,7 @@ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s) /* Get this show started by hooking up our callbacks */ aio_context_acquire(s->ctx); + virtio_set_queue_aio(s->vq, virtio_blk_data_plane_handle_output); virtio_queue_aio_set_host_notifier_handler(s->vq, s->ctx, true, true); aio_context_release(s->ctx); return; @@ -262,6 +274,7 @@ void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s) /* Stop notifications for new requests from guest */ virtio_queue_aio_set_host_notifier_handler(s->vq, s->ctx, false, false); + virtio_set_queue_aio(s->vq, NULL); /* Drain and switch bs back to the QEMU main loop */ blk_set_aio_context(s->conf->conf.blk, qemu_get_aio_context()); diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 151fe788db..3f88f8cf59 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -578,20 +578,11 @@ void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) } } -static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) +void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq) { - VirtIOBlock *s = VIRTIO_BLK(vdev); VirtIOBlockReq *req; MultiReqBuffer mrb = {}; - /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start - * dataplane here instead of waiting for .set_status(). - */ - if (s->dataplane && !s->dataplane_started) { - virtio_blk_data_plane_start(s->dataplane); - return; - } - blk_io_plug(s->blk); while ((req = virtio_blk_get_request(s))) { @@ -605,6 +596,22 @@ static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) blk_io_unplug(s->blk); } +static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) +{ + VirtIOBlock *s = (VirtIOBlock *)vdev; + + if (s->dataplane) { + /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start + * dataplane here instead of waiting for .set_status(). + */ + virtio_blk_data_plane_start(s->dataplane); + if (!s->dataplane_disabled) { + return; + } + } + virtio_blk_handle_vq(s, vq); +} + static void virtio_blk_dma_restart_bh(void *opaque) { VirtIOBlock *s = opaque; |