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 <brouer@xxxxxxxxxx> Co-developed-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx> Signed-off-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx> Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx> --- include/net/page_pool.h | 26 ++++++++++++++++ net/core/page_pool.c | 69 +++++++++++++++++++++++++++++++++++------ net/core/xdp.c | 9 ++---- 3 files changed, 87 insertions(+), 17 deletions(-) diff --git a/include/net/page_pool.h b/include/net/page_pool.h index 81d7773f96cd..b5b195305346 100644 --- a/include/net/page_pool.h +++ b/include/net/page_pool.h @@ -152,6 +152,8 @@ 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) { @@ -165,6 +167,11 @@ 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, @@ -215,4 +222,23 @@ 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 ef98372facf6..a3e6051ac978 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -11,6 +11,8 @@ #include <linux/device.h> #include <net/page_pool.h> +#include <net/xdp.h> + #include <linux/dma-direction.h> #include <linux/dma-mapping.h> #include <linux/page-flags.h> @@ -362,8 +364,9 @@ 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 @@ -379,15 +382,12 @@ 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. * @@ -405,9 +405,58 @@ 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, pa_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])) + data[pa_len++] = data[i]; + } + page_pool_ring_unlock(pool); + + if (likely(!pa_len)) + return; + + /* ptr_ring cache full, free pages outside producer lock since + * put_page() with refcnt == 1 can be an expensive operation + */ + for (i = 0; i < pa_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; diff --git a/net/core/xdp.c b/net/core/xdp.c index bbaee7fdd44f..3d330ebda893 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -393,16 +393,11 @@ EXPORT_SYMBOL_GPL(xdp_return_frame_rx_napi); void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq) { struct xdp_mem_allocator *xa = bq->xa; - int i; - if (unlikely(!xa)) + if (unlikely(!xa || !bq->count)) return; - for (i = 0; i < bq->count; i++) { - struct page *page = virt_to_head_page(bq->q[i]); - - page_pool_put_full_page(xa->page_pool, page, false); - } + page_pool_put_page_bulk(xa->page_pool, bq->q, bq->count); /* bq->xa is not cleared to save lookup, if mem.id same in next bulk */ bq->count = 0; } -- 2.26.2