Re: [PATCH 3/4] drm/ttm: add page order support in ttm_pages_put

["Christian König" <ckoenig.leichtzumerken-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

Am 21.11.2017 um 10:32 schrieb Roger He:
> Change-Id: Ia55b206d95812c5afcfd6cec29f580758d1f50f0
> Signed-off-by: Roger He <Hongbo.He@amd.com>
> ---
>   drivers/gpu/drm/ttm/ttm_page_alloc.c | 42 +++++++++++++++++++++++++++++-------
>   1 file changed, 34 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c
> index 27b2402..90546fd 100644
> --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
> +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
> @@ -285,13 +285,39 @@ static struct ttm_page_pool *ttm_get_pool(int flags, bool huge,
>   }
>   
>   /* set memory back to wb and free the pages. */
> -static void ttm_pages_put(struct page *pages[], unsigned npages)
> +static void ttm_pages_put(struct page *pages[], unsigned npages,
> +		unsigned int order)
>   {
> -	unsigned i;
> -	if (set_pages_array_wb(pages, npages))
> -		pr_err("Failed to set %d pages to wb!\n", npages);
> -	for (i = 0; i < npages; ++i)
> -		__free_page(pages[i]);
> +	struct page **pages_to_free = NULL;
> +	struct page **pages_array = NULL;
> +	struct page *p = NULL;
> +	unsigned int i, j, pages_nr = 1 << order;
> +
> +	if (order > 0) {
> +		pages_to_free = kmalloc_array(pages_nr, sizeof(struct page *),
> +					GFP_KERNEL);

We can't call kmalloc here, when this function is called by the shrinker 
we are tight on memory anyway.

That's also the reason we have this static buffer dance in 
ttm_page_pool_free() as well.

Christian.

> +		if (!pages_to_free) {
> +			pr_err("Failed to allocate memory for ttm pages put operation\n");
> +			return;
> +		}
> +	}
> +
> +	for (i = 0; i < npages; ++i) {
> +		if (order) {
> +			p = pages[i];
> +			for (j = 0; j < pages_nr; ++j)
> +				pages_to_free[j] = p++;
> +
> +			pages_array = pages_to_free;
> +		} else
> +			pages_array = pages;
> +
> +		if (set_pages_array_wb(pages_array, pages_nr))
> +			pr_err("Failed to set %d pages to wb!\n", pages_nr);
> +		__free_pages(pages[i], order);
> +	}
> +
> +	kfree(pages_to_free);
>   }
>   
>   static void ttm_pool_update_free_locked(struct ttm_page_pool *pool,
> @@ -354,7 +380,7 @@ static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free,
>   			 */
>   			spin_unlock_irqrestore(&pool->lock, irq_flags);
>   
> -			ttm_pages_put(pages_to_free, freed_pages);
> +			ttm_pages_put(pages_to_free, freed_pages, pool->order);
>   			if (likely(nr_free != FREE_ALL_PAGES))
>   				nr_free -= freed_pages;
>   
> @@ -389,7 +415,7 @@ static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free,
>   	spin_unlock_irqrestore(&pool->lock, irq_flags);
>   
>   	if (freed_pages)
> -		ttm_pages_put(pages_to_free, freed_pages);
> +		ttm_pages_put(pages_to_free, freed_pages, pool->order);
>   out:
>   	if (pages_to_free != static_buf)
>   		kfree(pages_to_free);


_______________________________________________
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx