On 2022-11-07 14:58, Christian König wrote:
> If we got a page pool use it as much as possible.
>
> If we can't get more pages from the pool allocate as much as possible.
>
> Only if that still doesn't work reduce the order and try again.
>
> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
> ---
> drivers/gpu/drm/ttm/ttm_pool.c | 81 ++++++++++++++++++++++++----------
> 1 file changed, 57 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c
> index 21b61631f73a..cf15874cf380 100644
> --- a/drivers/gpu/drm/ttm/ttm_pool.c
> +++ b/drivers/gpu/drm/ttm/ttm_pool.c
> @@ -344,6 +344,27 @@ static unsigned int ttm_pool_page_order(struct ttm_pool *pool, struct page *p)
> return p->private;
> }
>
> +/* Called when we got a page, either from a pool or newly allocated */
> +int ttm_pool_page_allocated(struct ttm_pool *pool, unsigned int order,
> + struct page *p, dma_addr_t **dma_addr,
> + unsigned long *num_pages, struct page ***pages)
> +{
> + unsigned int i;
> + int r;
> +
> + if (*dma_addr) {
> + r = ttm_pool_map(pool, order, p, dma_addr);
> + if (r)
> + return r;
> + }
> +
> + *num_pages -= 1 << order;
> + for (i = 1 << order; i; --i)
> + *((*pages)++) = p++;
Since we're using a for-loop here anyway, perhaps it's better to simplify-clarify
this as:
for (i = 1 << order; i; i--, (*pages)++, p++)
**pages = p;
Regards,
Luben
> +
> + return 0;
> +}
> +
> /**
> * ttm_pool_alloc - Fill a ttm_tt object
> *
> @@ -385,45 +406,57 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt,
> for (order = min_t(unsigned int, MAX_ORDER - 1, __fls(num_pages));
> num_pages;
> order = min_t(unsigned int, order, __fls(num_pages))) {
> - bool apply_caching = false;
> struct ttm_pool_type *pt;
>
> pt = ttm_pool_select_type(pool, tt->caching, order);
> p = pt ? ttm_pool_type_take(pt) : NULL;
> if (p) {
> - apply_caching = true;
> - } else {
> - p = ttm_pool_alloc_page(pool, gfp_flags, order);
> - if (p && PageHighMem(p))
> - apply_caching = true;
> - }
> -
> - if (!p) {
> - if (order) {
> - --order;
> - continue;
> - }
> - r = -ENOMEM;
> - goto error_free_all;
> - }
> -
> - if (apply_caching) {
> r = ttm_pool_apply_caching(caching, pages,
> tt->caching);
> if (r)
> goto error_free_page;
> - caching = pages + (1 << order);
> +
> + while (p) {
> + r = ttm_pool_page_allocated(pool, order, p,
> + &dma_addr,
> + &num_pages,
> + &pages);
> + if (r)
> + goto error_free_page;
> +
> + if (num_pages < (1 << order))
> + break;
> +
> + p = ttm_pool_type_take(pt);
> + }
> + caching = pages;
> }
>
> - if (dma_addr) {
> - r = ttm_pool_map(pool, order, p, &dma_addr);
> + while (num_pages >= (1 << order) &&
> + (p = ttm_pool_alloc_page(pool, gfp_flags, order))) {
> +
> + if (PageHighMem(p)) {
> + r = ttm_pool_apply_caching(caching, pages,
> + tt->caching);
> + if (r)
> + goto error_free_page;
> + }
> + r = ttm_pool_page_allocated(pool, order, p, &dma_addr,
> + &num_pages, &pages);
> if (r)
> goto error_free_page;
> + if (PageHighMem(p))
> + caching = pages;
> }
>
> - num_pages -= 1 << order;
> - for (i = 1 << order; i; --i)
> - *(pages++) = p++;
> + if (!p) {
> + if (order) {
> + --order;
> + continue;
> + }
> + r = -ENOMEM;
> + goto error_free_all;
> + }
> }
>
> r = ttm_pool_apply_caching(caching, pages, tt->caching);
