From cc0037fa592d56e4abb9c7d1c52c4d2dc25cd906 Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Mon, 29 Jan 2024 11:26:45 +1000 Subject: [PATCH] nouveau: offload fence uevents work to workqueue 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 Link: https://patchwork.freedesktop.org/patch/576237/ Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/nouveau/nouveau_fence.c | 26 ++++++++++++++++++------- drivers/gpu/drm/nouveau/nouveau_fence.h | 1 + 2 files changed, 20 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c index ca762ea55413..93f08f9479d8 100644 --- 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 nouveau_fence_chan *fctx, int error) 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_channel *chan, struct nouveau_fence_chan *fc 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 nvif_event *event, void *repv, u32 repc 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; } - spin_unlock_irqrestore(&fctx->lock, flags); + if (drop) + nvif_event_block(&fctx->event); - return ret; + spin_unlock_irqrestore(&fctx->lock, flags); +} + +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_channel *chan, struct nouveau_fence_cha } 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); diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.h b/drivers/gpu/drm/nouveau/nouveau_fence.h index 64d33ae7f356..8bc065acfe35 100644 --- 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; };