From fa801e94e9cb8c4f10feac9f43f7f2dfb94aca85 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Thu, 11 Nov 2021 16:29:06 +0800 Subject: [PATCH] net: page_pool: Add bulk support for ptr_ring Introduce the capability to batch page_pool ptr_ring refill since it is usually run inside the driver NAPI tx completion loop. Suggested-by: Jesper Dangaard Brouer Co-developed-by: Jesper Dangaard Brouer Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Lorenzo Bianconi Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Acked-by: Ilias Apalodimas Link: https://lore.kernel.org/bpf/08dd249c9522c001313f520796faa777c4089e1c.1605267335.git.lorenzo@kernel.org Reviewed-by: Yongxin Li (fix conflicts: delete modifications to net/core/xdp.c) Signed-off-by: hongrongxuan --- include/net/page_pool.h | 26 +++++++++++++++ net/core/page_pool.c | 70 +++++++++++++++++++++++++++++++++++------ 2 files changed, 86 insertions(+), 10 deletions(-) diff --git a/include/net/page_pool.h b/include/net/page_pool.h index 1a5eb84c4e69..c904bede4d7b 100644 --- a/include/net/page_pool.h +++ b/include/net/page_pool.h @@ -150,6 +150,8 @@ struct page_pool *page_pool_create(const struct page_pool_params *params); void page_pool_destroy(struct page_pool *pool); void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *)); void page_pool_release_page(struct page_pool *pool, struct page *page); +void page_pool_put_page_bulk(struct page_pool *pool, void **data, + int count); #else static inline void page_pool_destroy(struct page_pool *pool) { @@ -163,6 +165,11 @@ static inline void page_pool_release_page(struct page_pool *pool, struct page *page) { } + +static inline void page_pool_put_page_bulk(struct page_pool *pool, void **data, + int count) +{ +} #endif void page_pool_put_page(struct page_pool *pool, struct page *page, @@ -223,4 +230,23 @@ static inline void page_pool_nid_changed(struct page_pool *pool, int new_nid) if (unlikely(pool->p.nid != new_nid)) page_pool_update_nid(pool, new_nid); } + +static inline void page_pool_ring_lock(struct page_pool *pool) + __acquires(&pool->ring.producer_lock) +{ + if (in_serving_softirq()) + spin_lock(&pool->ring.producer_lock); + else + spin_lock_bh(&pool->ring.producer_lock); +} + +static inline void page_pool_ring_unlock(struct page_pool *pool) + __releases(&pool->ring.producer_lock) +{ + if (in_serving_softirq()) + spin_unlock(&pool->ring.producer_lock); + else + spin_unlock_bh(&pool->ring.producer_lock); +} + #endif /* _NET_PAGE_POOL_H */ diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 4c7457eb7894..9735608f33b5 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -11,6 +11,8 @@ #include #include +#include + #include #include #include @@ -397,8 +399,9 @@ static bool pool_page_reusable(struct page_pool *pool, struct page *page) * If the page refcnt != 1, then the page will be returned to memory * subsystem. */ -void page_pool_put_page(struct page_pool *pool, struct page *page, - unsigned int dma_sync_size, bool allow_direct) +static __always_inline struct page * +__page_pool_put_page(struct page_pool *pool, struct page *page, + unsigned int dma_sync_size, bool allow_direct) { /* This allocator is optimized for the XDP mode that uses * one-frame-per-page, but have fallbacks that act like the @@ -414,15 +417,12 @@ void page_pool_put_page(struct page_pool *pool, struct page *page, page_pool_dma_sync_for_device(pool, page, dma_sync_size); - if (allow_direct && in_serving_softirq()) - if (page_pool_recycle_in_cache(page, pool)) - return; + if (allow_direct && in_serving_softirq() && + page_pool_recycle_in_cache(page, pool)) + return NULL; - if (!page_pool_recycle_in_ring(pool, page)) { - /* Cache full, fallback to free pages */ - page_pool_return_page(pool, page); - } - return; + /* Page found as candidate for recycling */ + return page; } /* Fallback/non-XDP mode: API user have elevated refcnt. * @@ -440,9 +440,59 @@ void page_pool_put_page(struct page_pool *pool, struct page *page, /* Do not replace this with page_pool_return_page() */ page_pool_release_page(pool, page); put_page(page); + + return NULL; +} + +void page_pool_put_page(struct page_pool *pool, struct page *page, + unsigned int dma_sync_size, bool allow_direct) +{ + page = __page_pool_put_page(pool, page, dma_sync_size, allow_direct); + if (page && !page_pool_recycle_in_ring(pool, page)) { + /* Cache full, fallback to free pages */ + page_pool_return_page(pool, page); + } } EXPORT_SYMBOL(page_pool_put_page); +/* Caller must not use data area after call, as this function overwrites it */ +void page_pool_put_page_bulk(struct page_pool *pool, void **data, + int count) +{ + int i, bulk_len = 0; + + for (i = 0; i < count; i++) { + struct page *page = virt_to_head_page(data[i]); + + page = __page_pool_put_page(pool, page, -1, false); + /* Approved for bulk recycling in ptr_ring cache */ + if (page) + data[bulk_len++] = page; + } + + if (unlikely(!bulk_len)) + return; + + /* Bulk producer into ptr_ring page_pool cache */ + page_pool_ring_lock(pool); + for (i = 0; i < bulk_len; i++) { + if (__ptr_ring_produce(&pool->ring, data[i])) + break; /* ring full */ + } + page_pool_ring_unlock(pool); + + /* Hopefully all pages was return into ptr_ring */ + if (likely(i == bulk_len)) + return; + + /* ptr_ring cache full, free remaining pages outside producer lock + * since put_page() with refcnt == 1 can be an expensive operation + */ + for (; i < bulk_len; i++) + page_pool_return_page(pool, data[i]); +} +EXPORT_SYMBOL(page_pool_put_page_bulk); + static void page_pool_empty_ring(struct page_pool *pool) { struct page *page;