[2/3] dma-buf: nuke DMA_FENCE_TRACE macros

Only the DRM GPU scheduler, radeon and amdgpu where using them and they depend
on a non existing config option to actually emit some code.

Nuke them and clean up the dma_fence_signal* return value.

Signed-off-by: Christian König <christian.koenig@amd.com>
---
 drivers/dma-buf/dma-fence.c               | 44 +++++------------------
 drivers/dma-buf/st-dma-fence.c            | 12 ++-----
 drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 10 +-----
 drivers/gpu/drm/radeon/radeon_fence.c     | 24 +++----------
 drivers/gpu/drm/scheduler/sched_fence.c   | 18 ++--------
 include/linux/dma-fence.h                 | 32 +++--------------
 6 files changed, 23 insertions(+), 117 deletions(-)

On Thu, Jul 29, 2021 at 09:03:29AM +0200, Christian König wrote:
> Only the DRM GPU scheduler, radeon and amdgpu where using them and they depend
> on a non existing config option to actually emit some code.
> 
> Nuke them and clean up the dma_fence_signal* return value.
> 
> Signed-off-by: Christian König <christian.koenig@amd.com>

So i915 is very much become a horror show of wheel reinventing (and we're
trying to fix that), but there's some legit hand-rolled use-cases for
having the return value of dma_fence_signal. We're not using that right
now because hand-rollled nonsense, but can you perhaps keep that part?

Other pieces lgtm.
-Daniel

> ---
>  drivers/dma-buf/dma-fence.c               | 44 +++++------------------
>  drivers/dma-buf/st-dma-fence.c            | 12 ++-----
>  drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 10 +-----
>  drivers/gpu/drm/radeon/radeon_fence.c     | 24 +++----------
>  drivers/gpu/drm/scheduler/sched_fence.c   | 18 ++--------
>  include/linux/dma-fence.h                 | 32 +++--------------
>  6 files changed, 23 insertions(+), 117 deletions(-)
> 
> diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c
> index ce0f5eff575d..21cba0f74e69 100644
> --- a/drivers/dma-buf/dma-fence.c
> +++ b/drivers/dma-buf/dma-fence.c
> @@ -350,12 +350,9 @@ void __dma_fence_might_wait(void)
>   *
>   * Unlike dma_fence_signal_timestamp(), this function must be called with
>   * &dma_fence.lock held.
> - *
> - * Returns 0 on success and a negative error value when @fence has been
> - * signalled already.
>   */
> -int dma_fence_signal_timestamp_locked(struct dma_fence *fence,
> -				      ktime_t timestamp)
> +void dma_fence_signal_timestamp_locked(struct dma_fence *fence,
> +				       ktime_t timestamp)
>  {
>  	struct dma_fence_cb *cur, *tmp;
>  	struct list_head cb_list;
> @@ -364,7 +361,7 @@ int dma_fence_signal_timestamp_locked(struct dma_fence *fence,
>  
>  	if (unlikely(test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
>  				      &fence->flags)))
> -		return -EINVAL;
> +		return;
>  
>  	/* Stash the cb_list before replacing it with the timestamp */
>  	list_replace(&fence->cb_list, &cb_list);
> @@ -377,8 +374,6 @@ int dma_fence_signal_timestamp_locked(struct dma_fence *fence,
>  		INIT_LIST_HEAD(&cur->node);
>  		cur->func(fence, cur);
>  	}
> -
> -	return 0;
>  }
>  EXPORT_SYMBOL(dma_fence_signal_timestamp_locked);
>  
> @@ -393,23 +388,14 @@ EXPORT_SYMBOL(dma_fence_signal_timestamp_locked);
>   * can only go from the unsignaled to the signaled state and not back, it will
>   * only be effective the first time. Set the timestamp provided as the fence
>   * signal timestamp.
> - *
> - * Returns 0 on success and a negative error value when @fence has been
> - * signalled already.
>   */
> -int dma_fence_signal_timestamp(struct dma_fence *fence, ktime_t timestamp)
> +void dma_fence_signal_timestamp(struct dma_fence *fence, ktime_t timestamp)
>  {
>  	unsigned long flags;
> -	int ret;
> -
> -	if (!fence)
> -		return -EINVAL;
>  
>  	spin_lock_irqsave(fence->lock, flags);
> -	ret = dma_fence_signal_timestamp_locked(fence, timestamp);
> +	dma_fence_signal_timestamp_locked(fence, timestamp);
>  	spin_unlock_irqrestore(fence->lock, flags);
> -
> -	return ret;
>  }
>  EXPORT_SYMBOL(dma_fence_signal_timestamp);
>  
> @@ -425,13 +411,10 @@ EXPORT_SYMBOL(dma_fence_signal_timestamp);
>   *
>   * Unlike dma_fence_signal(), this function must be called with &dma_fence.lock
>   * held.
> - *
> - * Returns 0 on success and a negative error value when @fence has been
> - * signalled already.
>   */
> -int dma_fence_signal_locked(struct dma_fence *fence)
> +void dma_fence_signal_locked(struct dma_fence *fence)
>  {
> -	return dma_fence_signal_timestamp_locked(fence, ktime_get());
> +	dma_fence_signal_timestamp_locked(fence, ktime_get());
>  }
>  EXPORT_SYMBOL(dma_fence_signal_locked);
>  
> @@ -444,28 +427,19 @@ EXPORT_SYMBOL(dma_fence_signal_locked);
>   * dma_fence_add_callback(). Can be called multiple times, but since a fence
>   * can only go from the unsignaled to the signaled state and not back, it will
>   * only be effective the first time.
> - *
> - * Returns 0 on success and a negative error value when @fence has been
> - * signalled already.
>   */
> -int dma_fence_signal(struct dma_fence *fence)
> +void dma_fence_signal(struct dma_fence *fence)
>  {
>  	unsigned long flags;
> -	int ret;
>  	bool tmp;
>  
> -	if (!fence)
> -		return -EINVAL;
> -
>  	tmp = dma_fence_begin_signalling();
>  
>  	spin_lock_irqsave(fence->lock, flags);
> -	ret = dma_fence_signal_timestamp_locked(fence, ktime_get());
> +	dma_fence_signal_timestamp_locked(fence, ktime_get());
>  	spin_unlock_irqrestore(fence->lock, flags);
>  
>  	dma_fence_end_signalling(tmp);
> -
> -	return ret;
>  }
>  EXPORT_SYMBOL(dma_fence_signal);
>  
> diff --git a/drivers/dma-buf/st-dma-fence.c b/drivers/dma-buf/st-dma-fence.c
> index c8a12d7ad71a..e89001d8873f 100644
> --- a/drivers/dma-buf/st-dma-fence.c
> +++ b/drivers/dma-buf/st-dma-fence.c
> @@ -122,21 +122,13 @@ static int test_signaling(void *arg)
>  		goto err_free;
>  	}
>  
> -	if (dma_fence_signal(f)) {
> -		pr_err("Fence reported being already signaled\n");
> -		goto err_free;
> -	}
> -
> +	dma_fence_signal(f);
>  	if (!dma_fence_is_signaled(f)) {
>  		pr_err("Fence not reporting signaled\n");
>  		goto err_free;
>  	}
>  
> -	if (!dma_fence_signal(f)) {
> -		pr_err("Fence reported not being already signaled\n");
> -		goto err_free;
> -	}
> -
> +	dma_fence_signal(f);
>  	err = 0;
>  err_free:
>  	dma_fence_put(f);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
> index d4547d195173..397872779c31 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
> @@ -246,7 +246,6 @@ bool amdgpu_fence_process(struct amdgpu_ring *ring)
>  	struct amdgpu_fence_driver *drv = &ring->fence_drv;
>  	struct amdgpu_device *adev = ring->adev;
>  	uint32_t seq, last_seq;
> -	int r;
>  
>  	do {
>  		last_seq = atomic_read(&ring->fence_drv.last_seq);
> @@ -278,12 +277,7 @@ bool amdgpu_fence_process(struct amdgpu_ring *ring)
>  		if (!fence)
>  			continue;
>  
> -		r = dma_fence_signal(fence);
> -		if (!r)
> -			DMA_FENCE_TRACE(fence, "signaled from irq context\n");
> -		else
> -			BUG();
> -
> +		dma_fence_signal(fence);
>  		dma_fence_put(fence);
>  		pm_runtime_mark_last_busy(adev_to_drm(adev)->dev);
>  		pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
> @@ -673,8 +667,6 @@ static bool amdgpu_fence_enable_signaling(struct dma_fence *f)
>  	if (!timer_pending(&ring->fence_drv.fallback_timer))
>  		amdgpu_fence_schedule_fallback(ring);
>  
> -	DMA_FENCE_TRACE(&fence->base, "armed on ring %i!\n", ring->idx);
> -
>  	return true;
>  }
>  
> diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c
> index 18f2c2e0dfb3..3f351d222cbb 100644
> --- a/drivers/gpu/drm/radeon/radeon_fence.c
> +++ b/drivers/gpu/drm/radeon/radeon_fence.c
> @@ -176,18 +176,11 @@ static int radeon_fence_check_signaled(wait_queue_entry_t *wait, unsigned mode,
>  	 */
>  	seq = atomic64_read(&fence->rdev->fence_drv[fence->ring].last_seq);
>  	if (seq >= fence->seq) {
> -		int ret = dma_fence_signal_locked(&fence->base);
> -
> -		if (!ret)
> -			DMA_FENCE_TRACE(&fence->base, "signaled from irq context\n");
> -		else
> -			DMA_FENCE_TRACE(&fence->base, "was already signaled\n");
> -
> +		dma_fence_signal_locked(&fence->base);
>  		radeon_irq_kms_sw_irq_put(fence->rdev, fence->ring);
>  		__remove_wait_queue(&fence->rdev->fence_queue, &fence->fence_wake);
>  		dma_fence_put(&fence->base);
> -	} else
> -		DMA_FENCE_TRACE(&fence->base, "pending\n");
> +	}
>  	return 0;
>  }
>  
> @@ -422,8 +415,6 @@ static bool radeon_fence_enable_signaling(struct dma_fence *f)
>  	fence->fence_wake.func = radeon_fence_check_signaled;
>  	__add_wait_queue(&rdev->fence_queue, &fence->fence_wake);
>  	dma_fence_get(f);
> -
> -	DMA_FENCE_TRACE(&fence->base, "armed on ring %i!\n", fence->ring);
>  	return true;
>  }
>  
> @@ -441,11 +432,7 @@ bool radeon_fence_signaled(struct radeon_fence *fence)
>  		return true;
>  
>  	if (radeon_fence_seq_signaled(fence->rdev, fence->seq, fence->ring)) {
> -		int ret;
> -
> -		ret = dma_fence_signal(&fence->base);
> -		if (!ret)
> -			DMA_FENCE_TRACE(&fence->base, "signaled from radeon_fence_signaled\n");
> +		dma_fence_signal(&fence->base);
>  		return true;
>  	}
>  	return false;
> @@ -550,7 +537,6 @@ long radeon_fence_wait_timeout(struct radeon_fence *fence, bool intr, long timeo
>  {
>  	uint64_t seq[RADEON_NUM_RINGS] = {};
>  	long r;
> -	int r_sig;
>  
>  	/*
>  	 * This function should not be called on !radeon fences.
> @@ -567,9 +553,7 @@ long radeon_fence_wait_timeout(struct radeon_fence *fence, bool intr, long timeo
>  		return r;
>  	}
>  
> -	r_sig = dma_fence_signal(&fence->base);
> -	if (!r_sig)
> -		DMA_FENCE_TRACE(&fence->base, "signaled from fence_wait\n");
> +	dma_fence_signal(&fence->base);
>  	return r;
>  }
>  
> diff --git a/drivers/gpu/drm/scheduler/sched_fence.c b/drivers/gpu/drm/scheduler/sched_fence.c
> index 69de2c76731f..3736746c47bd 100644
> --- a/drivers/gpu/drm/scheduler/sched_fence.c
> +++ b/drivers/gpu/drm/scheduler/sched_fence.c
> @@ -50,26 +50,12 @@ static void __exit drm_sched_fence_slab_fini(void)
>  
>  void drm_sched_fence_scheduled(struct drm_sched_fence *fence)
>  {
> -	int ret = dma_fence_signal(&fence->scheduled);
> -
> -	if (!ret)
> -		DMA_FENCE_TRACE(&fence->scheduled,
> -				"signaled from irq context\n");
> -	else
> -		DMA_FENCE_TRACE(&fence->scheduled,
> -				"was already signaled\n");
> +	dma_fence_signal(&fence->scheduled);
>  }
>  
>  void drm_sched_fence_finished(struct drm_sched_fence *fence)
>  {
> -	int ret = dma_fence_signal(&fence->finished);
> -
> -	if (!ret)
> -		DMA_FENCE_TRACE(&fence->finished,
> -				"signaled from irq context\n");
> -	else
> -		DMA_FENCE_TRACE(&fence->finished,
> -				"was already signaled\n");
> +	dma_fence_signal(&fence->finished);
>  }
>  
>  static const char *drm_sched_fence_get_driver_name(struct dma_fence *fence)
> diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h
> index 6ffb4b2c6371..027db23fd4e3 100644
> --- a/include/linux/dma-fence.h
> +++ b/include/linux/dma-fence.h
> @@ -370,11 +370,11 @@ static inline void dma_fence_end_signalling(bool cookie) {}
>  static inline void __dma_fence_might_wait(void) {}
>  #endif
>  
> -int dma_fence_signal(struct dma_fence *fence);
> -int dma_fence_signal_locked(struct dma_fence *fence);
> -int dma_fence_signal_timestamp(struct dma_fence *fence, ktime_t timestamp);
> -int dma_fence_signal_timestamp_locked(struct dma_fence *fence,
> -				      ktime_t timestamp);
> +void dma_fence_signal(struct dma_fence *fence);
> +void dma_fence_signal_locked(struct dma_fence *fence);
> +void dma_fence_signal_timestamp(struct dma_fence *fence, ktime_t timestamp);
> +void dma_fence_signal_timestamp_locked(struct dma_fence *fence,
> +				       ktime_t timestamp);
>  signed long dma_fence_default_wait(struct dma_fence *fence,
>  				   bool intr, signed long timeout);
>  int dma_fence_add_callback(struct dma_fence *fence,
> @@ -590,26 +590,4 @@ struct dma_fence *dma_fence_get_stub(void);
>  struct dma_fence *dma_fence_allocate_private_stub(void);
>  u64 dma_fence_context_alloc(unsigned num);
>  
> -#define DMA_FENCE_TRACE(f, fmt, args...) \
> -	do {								\
> -		struct dma_fence *__ff = (f);				\
> -		if (IS_ENABLED(CONFIG_DMA_FENCE_TRACE))			\
> -			pr_info("f %llu#%llu: " fmt,			\
> -				__ff->context, __ff->seqno, ##args);	\
> -	} while (0)
> -
> -#define DMA_FENCE_WARN(f, fmt, args...) \
> -	do {								\
> -		struct dma_fence *__ff = (f);				\
> -		pr_warn("f %llu#%llu: " fmt, __ff->context, __ff->seqno,\
> -			 ##args);					\
> -	} while (0)
> -
> -#define DMA_FENCE_ERR(f, fmt, args...) \
> -	do {								\
> -		struct dma_fence *__ff = (f);				\
> -		pr_err("f %llu#%llu: " fmt, __ff->context, __ff->seqno,	\
> -			##args);					\
> -	} while (0)
> -
>  #endif /* __LINUX_DMA_FENCE_H */
> -- 
> 2.25.1
>