| Message ID | 20200607212522.16935-3-imre.deak@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] drm/dp_mst: Fix the DDC I2C device unregistration of an MST port | expand |
On Mon, Jun 08, 2020 at 12:25:22AM +0300, Imre Deak wrote: > Atm, a pending delayed destroy work during module removal will be > canceled, leaving behind MST ports, mstbs. Fix this by using a dedicated > workqueue which will be drained of requeued items as well when > destroying it. > Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com> > Signed-off-by: Imre Deak <imre.deak@intel.com> > --- > drivers/gpu/drm/drm_dp_mst_topology.c | 17 ++++++++++++++--- > include/drm/drm_dp_mst_helper.h | 8 ++++++++ > 2 files changed, 22 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c > index 083255c33ee0..075fb5ac9264 100644 > --- a/drivers/gpu/drm/drm_dp_mst_topology.c > +++ b/drivers/gpu/drm/drm_dp_mst_topology.c > @@ -1630,7 +1630,7 @@ static void drm_dp_destroy_mst_branch_device(struct kref *kref) > mutex_lock(&mgr->delayed_destroy_lock); > list_add(&mstb->destroy_next, &mgr->destroy_branch_device_list); > mutex_unlock(&mgr->delayed_destroy_lock); > - schedule_work(&mgr->delayed_destroy_work); > + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); > } > > /** > @@ -1747,7 +1747,7 @@ static void drm_dp_destroy_port(struct kref *kref) > mutex_lock(&mgr->delayed_destroy_lock); > list_add(&port->next, &mgr->destroy_port_list); > mutex_unlock(&mgr->delayed_destroy_lock); > - schedule_work(&mgr->delayed_destroy_work); > + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); > } > > /** > @@ -5208,6 +5208,15 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, > INIT_LIST_HEAD(&mgr->destroy_port_list); > INIT_LIST_HEAD(&mgr->destroy_branch_device_list); > INIT_LIST_HEAD(&mgr->up_req_list); > + > + /* > + * delayed_destroy_work will be queued on a dedicated WQ, so that any > + * requeuing will be also flushed when deiniting the topology manager. > + */ > + mgr->delayed_destroy_wq = alloc_ordered_workqueue("drm_dp_mst_wq", 0); > + if (mgr->delayed_destroy_wq == NULL) > + return -ENOMEM; > + > INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); > INIT_WORK(&mgr->tx_work, drm_dp_tx_work); > INIT_WORK(&mgr->delayed_destroy_work, drm_dp_delayed_destroy_work); > @@ -5252,7 +5261,9 @@ void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) > { > drm_dp_mst_topology_mgr_set_mst(mgr, false); > flush_work(&mgr->work); > - cancel_work_sync(&mgr->delayed_destroy_work); > + /* The following will also drain any requeued work on the WQ. */ > + destroy_workqueue(mgr->delayed_destroy_wq); > + mgr->delayed_destroy_wq = NULL; > mutex_lock(&mgr->payload_lock); > kfree(mgr->payloads); > mgr->payloads = NULL; > diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h > index b230ff6f7081..8b9eb4db3381 100644 > --- a/include/drm/drm_dp_mst_helper.h > +++ b/include/drm/drm_dp_mst_helper.h > @@ -681,6 +681,14 @@ struct drm_dp_mst_topology_mgr { > * @destroy_branch_device_list. > */ > struct mutex delayed_destroy_lock; > + > + /** > + * @delayed_destroy_wq: Workqueue used for delayed_destroy_work items. > + * A dedicated WQ makes it possible to drain any requeued work items > + * on it. > + */ > + struct workqueue_struct *delayed_destroy_wq; > + > /** > * @delayed_destroy_work: Work item to destroy MST port and branch > * devices, needed to avoid locking inversion. > -- > 2.23.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 083255c33ee0..075fb5ac9264 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -1630,7 +1630,7 @@ static void drm_dp_destroy_mst_branch_device(struct kref *kref) mutex_lock(&mgr->delayed_destroy_lock); list_add(&mstb->destroy_next, &mgr->destroy_branch_device_list); mutex_unlock(&mgr->delayed_destroy_lock); - schedule_work(&mgr->delayed_destroy_work); + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); } /** @@ -1747,7 +1747,7 @@ static void drm_dp_destroy_port(struct kref *kref) mutex_lock(&mgr->delayed_destroy_lock); list_add(&port->next, &mgr->destroy_port_list); mutex_unlock(&mgr->delayed_destroy_lock); - schedule_work(&mgr->delayed_destroy_work); + queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); } /** @@ -5208,6 +5208,15 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, INIT_LIST_HEAD(&mgr->destroy_port_list); INIT_LIST_HEAD(&mgr->destroy_branch_device_list); INIT_LIST_HEAD(&mgr->up_req_list); + + /* + * delayed_destroy_work will be queued on a dedicated WQ, so that any + * requeuing will be also flushed when deiniting the topology manager. + */ + mgr->delayed_destroy_wq = alloc_ordered_workqueue("drm_dp_mst_wq", 0); + if (mgr->delayed_destroy_wq == NULL) + return -ENOMEM; + INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); INIT_WORK(&mgr->tx_work, drm_dp_tx_work); INIT_WORK(&mgr->delayed_destroy_work, drm_dp_delayed_destroy_work); @@ -5252,7 +5261,9 @@ void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) { drm_dp_mst_topology_mgr_set_mst(mgr, false); flush_work(&mgr->work); - cancel_work_sync(&mgr->delayed_destroy_work); + /* The following will also drain any requeued work on the WQ. */ + destroy_workqueue(mgr->delayed_destroy_wq); + mgr->delayed_destroy_wq = NULL; mutex_lock(&mgr->payload_lock); kfree(mgr->payloads); mgr->payloads = NULL; diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h index b230ff6f7081..8b9eb4db3381 100644 --- a/include/drm/drm_dp_mst_helper.h +++ b/include/drm/drm_dp_mst_helper.h @@ -681,6 +681,14 @@ struct drm_dp_mst_topology_mgr { * @destroy_branch_device_list. */ struct mutex delayed_destroy_lock; + + /** + * @delayed_destroy_wq: Workqueue used for delayed_destroy_work items. + * A dedicated WQ makes it possible to drain any requeued work items + * on it. + */ + struct workqueue_struct *delayed_destroy_wq; + /** * @delayed_destroy_work: Work item to destroy MST port and branch * devices, needed to avoid locking inversion.
Atm, a pending delayed destroy work during module removal will be canceled, leaving behind MST ports, mstbs. Fix this by using a dedicated workqueue which will be drained of requeued items as well when destroying it. Signed-off-by: Imre Deak <imre.deak@intel.com> --- drivers/gpu/drm/drm_dp_mst_topology.c | 17 ++++++++++++++--- include/drm/drm_dp_mst_helper.h | 8 ++++++++ 2 files changed, 22 insertions(+), 3 deletions(-)