diff mbox series

drm/i915: Break up error capture compression loops with cond_resched()

Message ID 20200820141546.21194-1-chris@chris-wilson.co.uk (mailing list archive)
State New, archived
Headers show
Series drm/i915: Break up error capture compression loops with cond_resched() | expand

Commit Message

Chris Wilson Aug. 20, 2020, 2:15 p.m. UTC
As the error capture will compress user buffers as directed to by the
user, it can take an arbitrary amount of time and space. Break up the
compression loops with a call to cond_resched(), that will allow other
processes to schedule (avoiding the soft lockups) and also serve as a
warning should we try to make this loop atomic in the future.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: stable@vger.kernel.org
---
 drivers/gpu/drm/i915/i915_gpu_error.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Mika Kuoppala Aug. 24, 2020, 10:53 a.m. UTC | #1
Chris Wilson <chris@chris-wilson.co.uk> writes:

> As the error capture will compress user buffers as directed to by the
> user, it can take an arbitrary amount of time and space. Break up the
> compression loops with a call to cond_resched(), that will allow other
> processes to schedule (avoiding the soft lockups) and also serve as a
> warning should we try to make this loop atomic in the future.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
> Cc: stable@vger.kernel.org

Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>

> ---
>  drivers/gpu/drm/i915/i915_gpu_error.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
> index 6a3a2ce0b394..6551ff04d5a6 100644
> --- a/drivers/gpu/drm/i915/i915_gpu_error.c
> +++ b/drivers/gpu/drm/i915/i915_gpu_error.c
> @@ -311,6 +311,8 @@ static int compress_page(struct i915_vma_compress *c,
>  
>  		if (zlib_deflate(zstream, Z_NO_FLUSH) != Z_OK)
>  			return -EIO;
> +
> +		cond_resched();
>  	} while (zstream->avail_in);
>  
>  	/* Fallback to uncompressed if we increase size? */
> @@ -397,6 +399,7 @@ static int compress_page(struct i915_vma_compress *c,
>  	if (!(wc && i915_memcpy_from_wc(ptr, src, PAGE_SIZE)))
>  		memcpy(ptr, src, PAGE_SIZE);
>  	dst->pages[dst->page_count++] = ptr;
> +	cond_resched();
>  
>  	return 0;
>  }
> -- 
> 2.20.1
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 6a3a2ce0b394..6551ff04d5a6 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -311,6 +311,8 @@  static int compress_page(struct i915_vma_compress *c,
 
 		if (zlib_deflate(zstream, Z_NO_FLUSH) != Z_OK)
 			return -EIO;
+
+		cond_resched();
 	} while (zstream->avail_in);
 
 	/* Fallback to uncompressed if we increase size? */
@@ -397,6 +399,7 @@  static int compress_page(struct i915_vma_compress *c,
 	if (!(wc && i915_memcpy_from_wc(ptr, src, PAGE_SIZE)))
 		memcpy(ptr, src, PAGE_SIZE);
 	dst->pages[dst->page_count++] = ptr;
+	cond_resched();
 
 	return 0;
 }