diff mbox series

[v2,4/8] drm/etnaviv: replace MMU flush marker with flush sequence

Message ID 20190705171727.27501-4-l.stach@pengutronix.de (mailing list archive)
State New, archived
Headers show
Series [v2,1/8] drm/etnaviv: simplify unbind checks | expand

Commit Message

Lucas Stach July 5, 2019, 5:17 p.m. UTC
If a MMU is shared between multiple GPUs, all of them need to flush their
TLBs, so a single marker that gets reset on the first flush won't do.
Replace the flush marker with a sequence number, so that it's possible to
check if the TLB is in sync with the current page table state for each GPU.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
---
 drivers/gpu/drm/etnaviv/etnaviv_buffer.c | 9 +++++----
 drivers/gpu/drm/etnaviv/etnaviv_gpu.h    | 1 +
 drivers/gpu/drm/etnaviv/etnaviv_mmu.c    | 6 +++---
 drivers/gpu/drm/etnaviv/etnaviv_mmu.h    | 2 +-
 4 files changed, 10 insertions(+), 8 deletions(-)

Comments

Philipp Zabel July 24, 2019, 3:45 p.m. UTC | #1
On Fri, 2019-07-05 at 19:17 +0200, Lucas Stach wrote:
> If a MMU is shared between multiple GPUs, all of them need to flush their
> TLBs, so a single marker that gets reset on the first flush won't do.
> Replace the flush marker with a sequence number, so that it's possible to
> check if the TLB is in sync with the current page table state for each GPU.
> 
> Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
> ---
>  drivers/gpu/drm/etnaviv/etnaviv_buffer.c | 9 +++++----
>  drivers/gpu/drm/etnaviv/etnaviv_gpu.h    | 1 +
>  drivers/gpu/drm/etnaviv/etnaviv_mmu.c    | 6 +++---
>  drivers/gpu/drm/etnaviv/etnaviv_mmu.h    | 2 +-
>  4 files changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
> index 6400a88cd778..532db77624da 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
> @@ -315,6 +315,7 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  	u32 return_target, return_dwords;
>  	u32 link_target, link_dwords;
>  	bool switch_context = gpu->exec_state != exec_state;
> +	bool need_flush = gpu->flush_seq != gpu->mmu->flush_seq;

Can gpu->mmu->flush_seq change between here ...

>  	lockdep_assert_held(&gpu->lock);
>  
> @@ -329,14 +330,14 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  	 * need to append a mmu flush load state, followed by a new
>  	 * link to this buffer - a total of four additional words.
>  	 */
> -	if (gpu->mmu->need_flush || switch_context) {
> +	if (need_flush || switch_context) {
>  		u32 target, extra_dwords;
>  
>  		/* link command */
>  		extra_dwords = 1;
>  
>  		/* flush command */
> -		if (gpu->mmu->need_flush) {
> +		if (need_flush) {
>  			if (gpu->mmu->version == ETNAVIV_IOMMU_V1)
>  				extra_dwords += 1;
>  			else
> @@ -349,7 +350,7 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  
>  		target = etnaviv_buffer_reserve(gpu, buffer, extra_dwords);
>  
> -		if (gpu->mmu->need_flush) {
> +		if (need_flush) {
>  			/* Add the MMU flush */
>  			if (gpu->mmu->version == ETNAVIV_IOMMU_V1) {
>  				CMD_LOAD_STATE(buffer, VIVS_GL_FLUSH_MMU,
> @@ -369,7 +370,7 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  					SYNC_RECIPIENT_PE);
>  			}
>  
> -			gpu->mmu->need_flush = false;
> +			gpu->flush_seq = gpu->mmu->flush_seq;

... and here? If so, gpu->flush_seq should be set to the value
that gpu->mmu->flush_seq had when need_flush was determined.

>  		}
>  
>  		if (switch_context) {
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
> index 933c8d016f11..96380942cd8c 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
> @@ -137,6 +137,7 @@ struct etnaviv_gpu {
>  	int irq;
>  
>  	struct etnaviv_iommu *mmu;
> +	unsigned int flush_seq;
>  
>  	/* Power Control: */
>  	struct clk *clk_bus;
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
> index dd81376724d7..3348d9962177 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
> @@ -263,7 +263,7 @@ int etnaviv_iommu_map_gem(struct etnaviv_iommu *mmu,
>  	}
>  
>  	list_add_tail(&mapping->mmu_node, &mmu->mappings);
> -	mmu->need_flush = true;
> +	mmu->flush_seq++;
>  unlock:
>  	mutex_unlock(&mmu->lock);
>  
> @@ -282,7 +282,7 @@ void etnaviv_iommu_unmap_gem(struct etnaviv_iommu *mmu,
>  		etnaviv_iommu_remove_mapping(mmu, mapping);
>  
>  	list_del(&mapping->mmu_node);
> -	mmu->need_flush = true;
> +	mmu->flush_seq++;
>  	mutex_unlock(&mmu->lock);
>  }
>  
> @@ -371,7 +371,7 @@ int etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu *mmu,
>  		}
>  
>  		list_add_tail(&mapping->mmu_node, &mmu->mappings);
> -		mmu->need_flush = true;
> +		mmu->flush_seq++;
>  	}
>  
>  	mapping->use = 1;
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.h b/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
> index fe1c9d6b9334..34afe25df9ca 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
> @@ -48,7 +48,7 @@ struct etnaviv_iommu {
>  	struct mutex lock;
>  	struct list_head mappings;
>  	struct drm_mm mm;
> -	bool need_flush;
> +	unsigned int flush_seq;
>  };
>  
>  struct etnaviv_gem_object;

regards
Philipp
Guido Günther Aug. 13, 2019, 3:27 p.m. UTC | #2
Hi,
On Fri, Jul 05, 2019 at 07:17:23PM +0200, Lucas Stach wrote:
> If a MMU is shared between multiple GPUs, all of them need to flush their
> TLBs, so a single marker that gets reset on the first flush won't do.
> Replace the flush marker with a sequence number, so that it's possible to
> check if the TLB is in sync with the current page table state for each GPU.
> 
> Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

Reviewed-by: Guido Günther <agx@sigxcpu.org>

> ---
>  drivers/gpu/drm/etnaviv/etnaviv_buffer.c | 9 +++++----
>  drivers/gpu/drm/etnaviv/etnaviv_gpu.h    | 1 +
>  drivers/gpu/drm/etnaviv/etnaviv_mmu.c    | 6 +++---
>  drivers/gpu/drm/etnaviv/etnaviv_mmu.h    | 2 +-
>  4 files changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
> index 6400a88cd778..532db77624da 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
> @@ -315,6 +315,7 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  	u32 return_target, return_dwords;
>  	u32 link_target, link_dwords;
>  	bool switch_context = gpu->exec_state != exec_state;
> +	bool need_flush = gpu->flush_seq != gpu->mmu->flush_seq;
>  
>  	lockdep_assert_held(&gpu->lock);
>  
> @@ -329,14 +330,14 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  	 * need to append a mmu flush load state, followed by a new
>  	 * link to this buffer - a total of four additional words.
>  	 */
> -	if (gpu->mmu->need_flush || switch_context) {
> +	if (need_flush || switch_context) {
>  		u32 target, extra_dwords;
>  
>  		/* link command */
>  		extra_dwords = 1;
>  
>  		/* flush command */
> -		if (gpu->mmu->need_flush) {
> +		if (need_flush) {
>  			if (gpu->mmu->version == ETNAVIV_IOMMU_V1)
>  				extra_dwords += 1;
>  			else
> @@ -349,7 +350,7 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  
>  		target = etnaviv_buffer_reserve(gpu, buffer, extra_dwords);
>  
> -		if (gpu->mmu->need_flush) {
> +		if (need_flush) {
>  			/* Add the MMU flush */
>  			if (gpu->mmu->version == ETNAVIV_IOMMU_V1) {
>  				CMD_LOAD_STATE(buffer, VIVS_GL_FLUSH_MMU,
> @@ -369,7 +370,7 @@ void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
>  					SYNC_RECIPIENT_PE);
>  			}
>  
> -			gpu->mmu->need_flush = false;
> +			gpu->flush_seq = gpu->mmu->flush_seq;
>  		}
>  
>  		if (switch_context) {
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
> index 933c8d016f11..96380942cd8c 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
> @@ -137,6 +137,7 @@ struct etnaviv_gpu {
>  	int irq;
>  
>  	struct etnaviv_iommu *mmu;
> +	unsigned int flush_seq;
>  
>  	/* Power Control: */
>  	struct clk *clk_bus;
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
> index dd81376724d7..3348d9962177 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
> @@ -263,7 +263,7 @@ int etnaviv_iommu_map_gem(struct etnaviv_iommu *mmu,
>  	}
>  
>  	list_add_tail(&mapping->mmu_node, &mmu->mappings);
> -	mmu->need_flush = true;
> +	mmu->flush_seq++;
>  unlock:
>  	mutex_unlock(&mmu->lock);
>  
> @@ -282,7 +282,7 @@ void etnaviv_iommu_unmap_gem(struct etnaviv_iommu *mmu,
>  		etnaviv_iommu_remove_mapping(mmu, mapping);
>  
>  	list_del(&mapping->mmu_node);
> -	mmu->need_flush = true;
> +	mmu->flush_seq++;
>  	mutex_unlock(&mmu->lock);
>  }
>  
> @@ -371,7 +371,7 @@ int etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu *mmu,
>  		}
>  
>  		list_add_tail(&mapping->mmu_node, &mmu->mappings);
> -		mmu->need_flush = true;
> +		mmu->flush_seq++;
>  	}
>  
>  	mapping->use = 1;
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.h b/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
> index fe1c9d6b9334..34afe25df9ca 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
> @@ -48,7 +48,7 @@ struct etnaviv_iommu {
>  	struct mutex lock;
>  	struct list_head mappings;
>  	struct drm_mm mm;
> -	bool need_flush;
> +	unsigned int flush_seq;
>  };
>  
>  struct etnaviv_gem_object;
> -- 
> 2.20.1
> 
> _______________________________________________
> etnaviv mailing list
> etnaviv@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/etnaviv
diff mbox series

Patch

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
index 6400a88cd778..532db77624da 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
@@ -315,6 +315,7 @@  void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
 	u32 return_target, return_dwords;
 	u32 link_target, link_dwords;
 	bool switch_context = gpu->exec_state != exec_state;
+	bool need_flush = gpu->flush_seq != gpu->mmu->flush_seq;
 
 	lockdep_assert_held(&gpu->lock);
 
@@ -329,14 +330,14 @@  void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
 	 * need to append a mmu flush load state, followed by a new
 	 * link to this buffer - a total of four additional words.
 	 */
-	if (gpu->mmu->need_flush || switch_context) {
+	if (need_flush || switch_context) {
 		u32 target, extra_dwords;
 
 		/* link command */
 		extra_dwords = 1;
 
 		/* flush command */
-		if (gpu->mmu->need_flush) {
+		if (need_flush) {
 			if (gpu->mmu->version == ETNAVIV_IOMMU_V1)
 				extra_dwords += 1;
 			else
@@ -349,7 +350,7 @@  void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
 
 		target = etnaviv_buffer_reserve(gpu, buffer, extra_dwords);
 
-		if (gpu->mmu->need_flush) {
+		if (need_flush) {
 			/* Add the MMU flush */
 			if (gpu->mmu->version == ETNAVIV_IOMMU_V1) {
 				CMD_LOAD_STATE(buffer, VIVS_GL_FLUSH_MMU,
@@ -369,7 +370,7 @@  void etnaviv_buffer_queue(struct etnaviv_gpu *gpu, u32 exec_state,
 					SYNC_RECIPIENT_PE);
 			}
 
-			gpu->mmu->need_flush = false;
+			gpu->flush_seq = gpu->mmu->flush_seq;
 		}
 
 		if (switch_context) {
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
index 933c8d016f11..96380942cd8c 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
@@ -137,6 +137,7 @@  struct etnaviv_gpu {
 	int irq;
 
 	struct etnaviv_iommu *mmu;
+	unsigned int flush_seq;
 
 	/* Power Control: */
 	struct clk *clk_bus;
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
index dd81376724d7..3348d9962177 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.c
@@ -263,7 +263,7 @@  int etnaviv_iommu_map_gem(struct etnaviv_iommu *mmu,
 	}
 
 	list_add_tail(&mapping->mmu_node, &mmu->mappings);
-	mmu->need_flush = true;
+	mmu->flush_seq++;
 unlock:
 	mutex_unlock(&mmu->lock);
 
@@ -282,7 +282,7 @@  void etnaviv_iommu_unmap_gem(struct etnaviv_iommu *mmu,
 		etnaviv_iommu_remove_mapping(mmu, mapping);
 
 	list_del(&mapping->mmu_node);
-	mmu->need_flush = true;
+	mmu->flush_seq++;
 	mutex_unlock(&mmu->lock);
 }
 
@@ -371,7 +371,7 @@  int etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu *mmu,
 		}
 
 		list_add_tail(&mapping->mmu_node, &mmu->mappings);
-		mmu->need_flush = true;
+		mmu->flush_seq++;
 	}
 
 	mapping->use = 1;
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_mmu.h b/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
index fe1c9d6b9334..34afe25df9ca 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_mmu.h
@@ -48,7 +48,7 @@  struct etnaviv_iommu {
 	struct mutex lock;
 	struct list_head mappings;
 	struct drm_mm mm;
-	bool need_flush;
+	unsigned int flush_seq;
 };
 
 struct etnaviv_gem_object;