[PATCH net-next 2/7] page_pool: support non-split page with PP_FLAG_PAGE_FRAG

From: Yunsheng Lin
Date: Wed Sep 22 2021 - 05:43:29 EST


Currently when PP_FLAG_PAGE_FRAG is set, the caller is not
expected to call page_pool_alloc_pages() directly because of
the PP_FLAG_PAGE_FRAG checking in __page_pool_put_page().

The patch removes the above checking to enable non-split page
support when PP_FLAG_PAGE_FRAG is set.

Reviewed-by: Alexander Duyck <alexanderduyck@xxxxxx>
Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
---
net/core/page_pool.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index a65bd7972e37..f7e71dcb6a2e 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -315,11 +315,14 @@ struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp)

/* Fast-path: Get a page from cache */
page = __page_pool_get_cached(pool);
- if (page)
- return page;

/* Slow-path: cache empty, do real allocation */
- page = __page_pool_alloc_pages_slow(pool, gfp);
+ if (!page)
+ page = __page_pool_alloc_pages_slow(pool, gfp);
+
+ if (likely(page))
+ page_pool_set_frag_count(page, 1);
+
return page;
}
EXPORT_SYMBOL(page_pool_alloc_pages);
@@ -428,8 +431,7 @@ __page_pool_put_page(struct page_pool *pool, struct page *page,
unsigned int dma_sync_size, bool allow_direct)
{
/* It is not the last user for the page frag case */
- if (pool->p.flags & PP_FLAG_PAGE_FRAG &&
- page_pool_atomic_sub_frag_count_return(page, 1))
+ if (page_pool_atomic_sub_frag_count_return(page, 1))
return NULL;

/* This allocator is optimized for the XDP mode that uses
--
2.33.0