[Linuxarm] Re: [PATCH net-next] net: page_pool: minor optimization for page allocation

Reviewed-by: Jie Wang wangjie125@huawei.com

On 2022/10/28 9:07, Yunsheng Lin wrote:

Remove some redundant assignment in page allocation process.

Signed-off-by: Yunsheng Lin linyunsheng@huawei.com

net/core/page_pool.c | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 9b203d8660e4..afc6878b3b5b 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -278,18 +278,14 @@ static struct page *page_pool_refill_alloc_cache(struct page_pool *pool) /* fast path */ static struct page *__page_pool_get_cached(struct page_pool *pool) {

• struct page *page;
• /* Caller MUST guarantee safe non-concurrent access, e.g. softirq */ if (likely(pool->alloc.count)) { /* Fast-path */

• page = pool->alloc.cache[--pool->alloc.count];
  

  alloc_stat_inc(pool, fast);
• } else {

• page = page_pool_refill_alloc_cache(pool);
  

• return pool->alloc.cache[--pool->alloc.count];
  

  }

• return page;

• return page_pool_refill_alloc_cache(pool);

}

static void page_pool_dma_sync_for_device(struct page_pool *pool, @@ -415,14 +411,11 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool,

/* Return last page */ if (likely(pool->alloc.count > 0)) {

• page = pool->alloc.cache[--pool->alloc.count];
  

  alloc_stat_inc(pool, slow);
• } else {

• page = NULL;
  

• return pool->alloc.cache[--pool->alloc.count];
  

  }

• /* When page just alloc'ed is should/must have refcnt 1. */
• return page;

• return NULL;

}

/* For using page_pool replace: alloc_pages() API calls, but provide @@ -438,8 +431,7 @@ struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp) return page;

/* Slow-path: cache empty, do real allocation */

• page = __page_pool_alloc_pages_slow(pool, gfp);
• return page;

• return __page_pool_alloc_pages_slow(pool, gfp);

} EXPORT_SYMBOL(page_pool_alloc_pages);