Commit 4d7acc8f authored by Dave Airlie's avatar Dave Airlie
Browse files

Revert "nouveau: push event block/allowing out of the fence context" 



This reverts commit eacabb54.

This commit causes some regressions in desktop usage, this will
reintroduce the original deadlock in DRI_PRIME situations, I've
got an idea to fix it by offloading to a workqueue in a different
spot, however this code has a race condition where we sometimes
miss interrupts so I'd like to fix that as well.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent 9c4a1126

drivers/gpu/drm/nouveau/nouveau_fence.c

+5 −23
Original line number Diff line number Diff line
@@ -62,7 +62,7 @@ nouveau_fence_signal(struct nouveau_fence *fence) 
	if (test_bit(DMA_FENCE_FLAG_USER_BITS, &fence->base.flags)) {

		struct nouveau_fence_chan *fctx = nouveau_fctx(fence);



		if (atomic_dec_and_test(&fctx->notify_ref))

		if (!--fctx->notify_ref)

			drop = 1;

	}
@@ -103,7 +103,6 @@ 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->allow_block_work);

	nouveau_fence_context_kill(fctx, 0);

	nvif_event_dtor(&fctx->event);

	fctx->dead = 1;
@@ -168,18 +167,6 @@ nouveau_fence_wait_uevent_handler(struct nvif_event *event, void *repv, u32 repc 
	return ret;

}



static void

nouveau_fence_work_allow_block(struct work_struct *work)

{

	struct nouveau_fence_chan *fctx = container_of(work, struct nouveau_fence_chan,

						       allow_block_work);



	if (atomic_read(&fctx->notify_ref) == 0)

		nvif_event_block(&fctx->event);

	else

		nvif_event_allow(&fctx->event);

}



void

nouveau_fence_context_new(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)

{
@@ -191,7 +178,6 @@ nouveau_fence_context_new(struct nouveau_channel *chan, struct nouveau_fence_cha 
	} args;

	int ret;



	INIT_WORK(&fctx->allow_block_work, nouveau_fence_work_allow_block);

	INIT_LIST_HEAD(&fctx->flip);

	INIT_LIST_HEAD(&fctx->pending);

	spin_lock_init(&fctx->lock);
@@ -535,19 +521,15 @@ static bool nouveau_fence_enable_signaling(struct dma_fence *f) 
	struct nouveau_fence *fence = from_fence(f);

	struct nouveau_fence_chan *fctx = nouveau_fctx(fence);

	bool ret;

	bool do_work;



	if (atomic_inc_return(&fctx->notify_ref) == 0)

		do_work = true;

	if (!fctx->notify_ref++)

		nvif_event_allow(&fctx->event);



	ret = nouveau_fence_no_signaling(f);

	if (ret)

		set_bit(DMA_FENCE_FLAG_USER_BITS, &fence->base.flags);

	else if (atomic_dec_and_test(&fctx->notify_ref))

		do_work = true;



	if (do_work)

		schedule_work(&fctx->allow_block_work);

	else if (!--fctx->notify_ref)

		nvif_event_block(&fctx->event);



	return ret;

}

drivers/gpu/drm/nouveau/nouveau_fence.h

+1 −4
Original line number Diff line number Diff line
@@ -3,7 +3,6 @@ 
#define __NOUVEAU_FENCE_H__



#include <linux/dma-fence.h>

#include <linux/workqueue.h>

#include <nvif/event.h>



struct nouveau_drm;
@@ -46,9 +45,7 @@ struct nouveau_fence_chan { 
	char name[32];



	struct nvif_event event;

	struct work_struct allow_block_work;

	atomic_t notify_ref;

	int dead, killed;

	int notify_ref, dead, killed;

};



struct nouveau_fence_priv {