6.6-stable review patch. If anyone has any objections, please let me know.
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From: Dave Airlie airlied@redhat.com
commit 39126abc5e20611579602f03b66627d7cd1422f0 upstream.
This should break the deadlock between the fctx lock and the irq lock.
This offloads the processing off the work from the irq into a workqueue.
Cc: linux-stable@vger.kernel.org Signed-off-by: Dave Airlie airlied@redhat.com Link: https://patchwork.freedesktop.org/patch/576237/ Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/nouveau/nouveau_fence.c | 24 ++++++++++++++++++------ drivers/gpu/drm/nouveau/nouveau_fence.h | 1 + 2 files changed, 19 insertions(+), 6 deletions(-)
--- a/drivers/gpu/drm/nouveau/nouveau_fence.c +++ b/drivers/gpu/drm/nouveau/nouveau_fence.c @@ -103,6 +103,7 @@ nouveau_fence_context_kill(struct nouvea void nouveau_fence_context_del(struct nouveau_fence_chan *fctx) { + cancel_work_sync(&fctx->uevent_work); nouveau_fence_context_kill(fctx, 0); nvif_event_dtor(&fctx->event); fctx->dead = 1; @@ -145,12 +146,13 @@ nouveau_fence_update(struct nouveau_chan return drop; }
-static int -nouveau_fence_wait_uevent_handler(struct nvif_event *event, void *repv, u32 repc) +static void +nouveau_fence_uevent_work(struct work_struct *work) { - struct nouveau_fence_chan *fctx = container_of(event, typeof(*fctx), event); + struct nouveau_fence_chan *fctx = container_of(work, struct nouveau_fence_chan, + uevent_work); unsigned long flags; - int ret = NVIF_EVENT_KEEP; + int drop = 0;
spin_lock_irqsave(&fctx->lock, flags); if (!list_empty(&fctx->pending)) { @@ -160,11 +162,20 @@ nouveau_fence_wait_uevent_handler(struct fence = list_entry(fctx->pending.next, typeof(*fence), head); chan = rcu_dereference_protected(fence->channel, lockdep_is_held(&fctx->lock)); if (nouveau_fence_update(chan, fctx)) - ret = NVIF_EVENT_DROP; + drop = 1; } + if (drop) + nvif_event_block(&fctx->event); + spin_unlock_irqrestore(&fctx->lock, flags); +}
- return ret; +static int +nouveau_fence_wait_uevent_handler(struct nvif_event *event, void *repv, u32 repc) +{ + struct nouveau_fence_chan *fctx = container_of(event, typeof(*fctx), event); + schedule_work(&fctx->uevent_work); + return NVIF_EVENT_KEEP; }
void @@ -178,6 +189,7 @@ nouveau_fence_context_new(struct nouveau } args; int ret;
+ INIT_WORK(&fctx->uevent_work, nouveau_fence_uevent_work); INIT_LIST_HEAD(&fctx->flip); INIT_LIST_HEAD(&fctx->pending); spin_lock_init(&fctx->lock); --- a/drivers/gpu/drm/nouveau/nouveau_fence.h +++ b/drivers/gpu/drm/nouveau/nouveau_fence.h @@ -44,6 +44,7 @@ struct nouveau_fence_chan { u32 context; char name[32];
+ struct work_struct uevent_work; struct nvif_event event; int notify_ref, dead, killed; };