On Tue, Feb 6, 2024 at 12:11 AM Alex Bennée wrote: > Albert Esteve writes: > > > Ensure that we cleanup all virtio shared > > resources when the vhost devices is cleaned > > up (after a hot unplug, or a crash). > > > > To do so, we add a new function to the virtio_dmabuf > > API called `virtio_dmabuf_vhost_cleanup`, which > > loop through the table and removes all > > resources owned by the vhost device parameter. > > > > Also, add a test to verify that the new > > function in the API behaves as expected. > > > > Signed-off-by: Albert Esteve > > Acked-by: Stefan Hajnoczi > > --- > > hw/display/virtio-dmabuf.c | 22 +++++++++++++++++++++ > > hw/virtio/vhost.c | 3 +++ > > include/hw/virtio/virtio-dmabuf.h | 10 ++++++++++ > > tests/unit/test-virtio-dmabuf.c | 33 +++++++++++++++++++++++++++++++ > > 4 files changed, 68 insertions(+) > > > > diff --git a/hw/display/virtio-dmabuf.c b/hw/display/virtio-dmabuf.c > > index 3dba4577ca..6688809777 100644 > > --- a/hw/display/virtio-dmabuf.c > > +++ b/hw/display/virtio-dmabuf.c > > @@ -136,6 +136,28 @@ SharedObjectType virtio_object_type(const QemuUUID > *uuid) > > return vso->type; > > } > > > > +static bool virtio_dmabuf_resource_is_owned(gpointer key, > > + gpointer value, > > + gpointer dev) > > +{ > > + VirtioSharedObject *vso; > > + > > + vso = (VirtioSharedObject *) value; > > + return vso->type == TYPE_VHOST_DEV && vso->value == dev; > > It's a bit surprising to see vso->value being an anonymous gpointer > rather than the proper type and a bit confusing between value and > vso->value. > > It is the signature required for this to be used with `g_hash_table_foreach_remove`. For the naming, the HashMap stores gpointers, that point to `VirtioSharedObject`, and these point to the underlying type (stored at `vso->value`). It may sound a bit confusing, but is a byproduct of the VirtioSharedObject indirection. Not sure which names could be more fit for this, but I'm open to change them. > > +} > > + > > +int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev) > > +{ > > + int num_removed; > > + > > + g_mutex_lock(&lock); > > + num_removed = g_hash_table_foreach_remove( > > + resource_uuids, (GHRFunc) virtio_dmabuf_resource_is_owned, dev); > > + g_mutex_unlock(&lock); > > I'll note if we used a QemuMutex for the lock we could: > > - use WITH_QEMU_LOCK_GUARD(&lock) { } > - enable QSP porfiling for the lock > > Was not aware of these QemuMutex's. I wouldn't mind changing the mutex in this file in a different commit. > > + > > + return num_removed; > > +} > > + > > void virtio_free_resources(void) > > { > > g_mutex_lock(&lock); > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > > index 2c9ac79468..c5622eac14 100644 > > --- a/hw/virtio/vhost.c > > +++ b/hw/virtio/vhost.c > > @@ -16,6 +16,7 @@ > > #include "qemu/osdep.h" > > #include "qapi/error.h" > > #include "hw/virtio/vhost.h" > > +#include "hw/virtio/virtio-dmabuf.h" > > #include "qemu/atomic.h" > > #include "qemu/range.h" > > #include "qemu/error-report.h" > > @@ -1599,6 +1600,8 @@ void vhost_dev_cleanup(struct vhost_dev *hdev) > > migrate_del_blocker(&hdev->migration_blocker); > > g_free(hdev->mem); > > g_free(hdev->mem_sections); > > + /* free virtio shared objects */ > > + virtio_dmabuf_vhost_cleanup(hdev); > > if (hdev->vhost_ops) { > > hdev->vhost_ops->vhost_backend_cleanup(hdev); > > } > > diff --git a/include/hw/virtio/virtio-dmabuf.h > b/include/hw/virtio/virtio-dmabuf.h > > index 627c3b6db7..73f70fb482 100644 > > --- a/include/hw/virtio/virtio-dmabuf.h > > +++ b/include/hw/virtio/virtio-dmabuf.h > > @@ -91,6 +91,16 @@ struct vhost_dev *virtio_lookup_vhost_device(const > QemuUUID *uuid); > > */ > > SharedObjectType virtio_object_type(const QemuUUID *uuid); > > > > +/** > > + * virtio_dmabuf_vhost_cleanup() - Destroys all entries of the shared > > + * resources lookup table that are owned by the vhost backend > > + * @dev: the pointer to the vhost device that owns the entries. Data is > owned > > + * by the called of the function. > > + * > > + * Return: the number of resource entries removed. > > + */ > > +int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev); > > + > > /** > > * virtio_free_resources() - Destroys all keys and values of the shared > > * resources lookup table, and frees them > > diff --git a/tests/unit/test-virtio-dmabuf.c > b/tests/unit/test-virtio-dmabuf.c > > index a45ec52f42..1c8123c2d2 100644 > > --- a/tests/unit/test-virtio-dmabuf.c > > +++ b/tests/unit/test-virtio-dmabuf.c > > @@ -103,6 +103,38 @@ static void test_add_invalid_resource(void) > > } > > } > > > > +static void test_cleanup_res(void) > > +{ > > + QemuUUID uuids[20], uuid_alt; > > + struct vhost_dev *dev = g_new0(struct vhost_dev, 1); > > + struct vhost_dev *dev_alt = g_new0(struct vhost_dev, 1); > > + int i, num_removed; > > + > > + for (i = 0; i < ARRAY_SIZE(uuids); ++i) { > > + qemu_uuid_generate(&uuids[i]); > > + virtio_add_vhost_device(&uuids[i], dev); > > + /* vhost device is found */ > > + g_assert(virtio_lookup_vhost_device(&uuids[i]) != NULL); > > + } > > + qemu_uuid_generate(&uuid_alt); > > + virtio_add_vhost_device(&uuid_alt, dev_alt); > > + /* vhost device is found */ > > + g_assert(virtio_lookup_vhost_device(&uuid_alt) != NULL); > > + /* cleanup all dev resources */ > > + num_removed = virtio_dmabuf_vhost_cleanup(dev); > > + g_assert_cmpint(num_removed, ==, ARRAY_SIZE(uuids)); > > + for (i = 0; i < ARRAY_SIZE(uuids); ++i) { > > + /* None of the dev resources is found after free'd */ > > + g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, -1); > > + } > > + /* uuid_alt is still in the hash table */ > > + g_assert(virtio_lookup_vhost_device(&uuid_alt) != NULL); > > + > > + virtio_free_resources(); > > + g_free(dev); > > + g_free(dev_alt); > > +} > > + > > static void test_free_resources(void) > > { > > QemuUUID uuids[20]; > > @@ -131,6 +163,7 @@ int main(int argc, char **argv) > > test_remove_invalid_resource); > > g_test_add_func("/virtio-dmabuf/add_invalid_res", > > test_add_invalid_resource); > > + g_test_add_func("/virtio-dmabuf/cleanup_dev", test_cleanup_res); > > g_test_add_func("/virtio-dmabuf/free_res", test_free_resources); > > > > return g_test_run(); > > -- > Alex Bennée > Virtualisation Tech Lead @ Linaro > >