diff mbox

[1/2] drm/ttm: swap consecutive allocated cached pages

Message ID 20171204114224.27712-1-christian.koenig@amd.com (mailing list archive)
State New, archived
Headers show

Commit Message

Christian König Dec. 4, 2017, 11:42 a.m. UTC
When we detect consecutive allocation of pages swap them to avoid
accidentally freeing them as huge page.

Signed-off-by: Christian König <christian.koenig@amd.com>
---
 drivers/gpu/drm/ttm/ttm_page_alloc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Michel Dänzer Dec. 4, 2017, 11:51 a.m. UTC | #1
On 2017-12-04 12:42 PM, Christian König wrote:
> When we detect consecutive allocation of pages swap them to avoid
> accidentally freeing them as huge page.
> 
> Signed-off-by: Christian König <christian.koenig@amd.com>
> ---
>  drivers/gpu/drm/ttm/ttm_page_alloc.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
> index c82d94cbbabc..60401350a01a 100644
> --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
> +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
> @@ -921,6 +921,14 @@ static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
>  				return -ENOMEM;
>  			}
>  
> +			/* Swap the pages if we detect consecutive order */
> +			if (i && pages[i - 1] == p - 1) {
> +				struct page *tmp = p;
> +
> +				p = pages[i - 1];
> +				pages[i - 1] = tmp;
> +			}
> +

Should be (something like):

		if (i && pages[i - 1] == p - 1)
			swap(pages[i - 1], p);
Christian König Dec. 4, 2017, 12:13 p.m. UTC | #2
Am 04.12.2017 um 12:51 schrieb Michel Dänzer:
> On 2017-12-04 12:42 PM, Christian König wrote:
>> When we detect consecutive allocation of pages swap them to avoid
>> accidentally freeing them as huge page.
>>
>> Signed-off-by: Christian König <christian.koenig@amd.com>
>> ---
>>   drivers/gpu/drm/ttm/ttm_page_alloc.c | 8 ++++++++
>>   1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
>> index c82d94cbbabc..60401350a01a 100644
>> --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
>> +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
>> @@ -921,6 +921,14 @@ static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
>>   				return -ENOMEM;
>>   			}
>>   
>> +			/* Swap the pages if we detect consecutive order */
>> +			if (i && pages[i - 1] == p - 1) {
>> +				struct page *tmp = p;
>> +
>> +				p = pages[i - 1];
>> +				pages[i - 1] = tmp;
>> +			}
>> +
> Should be (something like):
>
> 		if (i && pages[i - 1] == p - 1)
> 			swap(pages[i - 1], p);

Good point, updates patches send out a few seconds ago.

Please review,
Christian.
diff mbox

Patch

diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
index c82d94cbbabc..60401350a01a 100644
--- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
+++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
@@ -921,6 +921,14 @@  static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
 				return -ENOMEM;
 			}
 
+			/* Swap the pages if we detect consecutive order */
+			if (i && pages[i - 1] == p - 1) {
+				struct page *tmp = p;
+
+				p = pages[i - 1];
+				pages[i - 1] = tmp;
+			}
+
 			pages[i++] = p;
 			--npages;
 		}