From: Tariq Toukan Date: Thu, 15 Sep 2016 13:08:38 +0000 (+0300) Subject: net/mlx5e: Implement RX mapped page cache for page recycle X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4415a0319f92ea0d624fe11c917faf9114f89187;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git net/mlx5e: Implement RX mapped page cache for page recycle Instead of reallocating and mapping pages for RX data-path, recycle already used pages in a per ring cache. Performance tests: The following results were measured on a freshly booted system, giving optimal baseline performance, as high-order pages are yet to be fragmented and depleted. We ran pktgen single-stream benchmarks, with iptables-raw-drop: Single stride, 64 bytes: * 4,739,057 - baseline * 4,749,550 - order0 no cache * 4,786,899 - order0 with cache 1% gain Larger packets, no page cross, 1024 bytes: * 3,982,361 - baseline * 3,845,682 - order0 no cache * 4,127,852 - order0 with cache 3.7% gain Larger packets, every 3rd packet crosses a page, 1500 bytes: * 3,731,189 - baseline * 3,579,414 - order0 no cache * 3,931,708 - order0 with cache 5.4% gain Signed-off-by: Tariq Toukan Signed-off-by: Saeed Mahameed Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h index 401b2f7b165f..7dd4763e726e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h @@ -287,6 +287,18 @@ struct mlx5e_rx_am { /* Adaptive Moderation */ u8 tired; }; +/* a single cache unit is capable to serve one napi call (for non-striding rq) + * or a MPWQE (for striding rq). + */ +#define MLX5E_CACHE_UNIT (MLX5_MPWRQ_PAGES_PER_WQE > NAPI_POLL_WEIGHT ? \ + MLX5_MPWRQ_PAGES_PER_WQE : NAPI_POLL_WEIGHT) +#define MLX5E_CACHE_SIZE (2 * roundup_pow_of_two(MLX5E_CACHE_UNIT)) +struct mlx5e_page_cache { + u32 head; + u32 tail; + struct mlx5e_dma_info page_cache[MLX5E_CACHE_SIZE]; +}; + struct mlx5e_rq { /* data path */ struct mlx5_wq_ll wq; @@ -301,6 +313,8 @@ struct mlx5e_rq { struct mlx5e_tstamp *tstamp; struct mlx5e_rq_stats stats; struct mlx5e_cq cq; + struct mlx5e_page_cache page_cache; + mlx5e_fp_handle_rx_cqe handle_rx_cqe; mlx5e_fp_alloc_wqe alloc_wqe; mlx5e_fp_dealloc_wqe dealloc_wqe; @@ -651,6 +665,8 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget); int mlx5e_poll_rx_cq(struct mlx5e_cq *cq, int budget); void mlx5e_free_tx_descs(struct mlx5e_sq *sq); +void mlx5e_page_release(struct mlx5e_rq *rq, struct mlx5e_dma_info *dma_info, + bool recycle); void mlx5e_handle_rx_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe); void mlx5e_handle_rx_cqe_mpwrq(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe); bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 136554b77c3b..8595b507e200 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -141,6 +141,10 @@ static void mlx5e_update_sw_counters(struct mlx5e_priv *priv) s->rx_buff_alloc_err += rq_stats->buff_alloc_err; s->rx_cqe_compress_blks += rq_stats->cqe_compress_blks; s->rx_cqe_compress_pkts += rq_stats->cqe_compress_pkts; + s->rx_cache_reuse += rq_stats->cache_reuse; + s->rx_cache_full += rq_stats->cache_full; + s->rx_cache_empty += rq_stats->cache_empty; + s->rx_cache_busy += rq_stats->cache_busy; for (j = 0; j < priv->params.num_tc; j++) { sq_stats = &priv->channel[i]->sq[j].stats; @@ -475,6 +479,9 @@ static int mlx5e_create_rq(struct mlx5e_channel *c, INIT_WORK(&rq->am.work, mlx5e_rx_am_work); rq->am.mode = priv->params.rx_cq_period_mode; + rq->page_cache.head = 0; + rq->page_cache.tail = 0; + return 0; err_rq_wq_destroy: @@ -485,6 +492,8 @@ err_rq_wq_destroy: static void mlx5e_destroy_rq(struct mlx5e_rq *rq) { + int i; + switch (rq->wq_type) { case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ: mlx5e_rq_free_mpwqe_info(rq); @@ -493,6 +502,12 @@ static void mlx5e_destroy_rq(struct mlx5e_rq *rq) kfree(rq->skb); } + for (i = rq->page_cache.head; i != rq->page_cache.tail; + i = (i + 1) & (MLX5E_CACHE_SIZE - 1)) { + struct mlx5e_dma_info *dma_info = &rq->page_cache.page_cache[i]; + + mlx5e_page_release(rq, dma_info, false); + } mlx5_wq_destroy(&rq->wq_ctrl); } diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c index 0c34daa04c43..dc8677933f76 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c @@ -305,11 +305,55 @@ static inline void mlx5e_post_umr_wqe(struct mlx5e_rq *rq, u16 ix) mlx5e_tx_notify_hw(sq, &wqe->ctrl, 0); } +static inline bool mlx5e_rx_cache_put(struct mlx5e_rq *rq, + struct mlx5e_dma_info *dma_info) +{ + struct mlx5e_page_cache *cache = &rq->page_cache; + u32 tail_next = (cache->tail + 1) & (MLX5E_CACHE_SIZE - 1); + + if (tail_next == cache->head) { + rq->stats.cache_full++; + return false; + } + + cache->page_cache[cache->tail] = *dma_info; + cache->tail = tail_next; + return true; +} + +static inline bool mlx5e_rx_cache_get(struct mlx5e_rq *rq, + struct mlx5e_dma_info *dma_info) +{ + struct mlx5e_page_cache *cache = &rq->page_cache; + + if (unlikely(cache->head == cache->tail)) { + rq->stats.cache_empty++; + return false; + } + + if (page_ref_count(cache->page_cache[cache->head].page) != 1) { + rq->stats.cache_busy++; + return false; + } + + *dma_info = cache->page_cache[cache->head]; + cache->head = (cache->head + 1) & (MLX5E_CACHE_SIZE - 1); + rq->stats.cache_reuse++; + + dma_sync_single_for_device(rq->pdev, dma_info->addr, PAGE_SIZE, + DMA_FROM_DEVICE); + return true; +} + static inline int mlx5e_page_alloc_mapped(struct mlx5e_rq *rq, struct mlx5e_dma_info *dma_info) { - struct page *page = dev_alloc_page(); + struct page *page; + + if (mlx5e_rx_cache_get(rq, dma_info)) + return 0; + page = dev_alloc_page(); if (unlikely(!page)) return -ENOMEM; @@ -324,9 +368,12 @@ static inline int mlx5e_page_alloc_mapped(struct mlx5e_rq *rq, return 0; } -static inline void mlx5e_page_release(struct mlx5e_rq *rq, - struct mlx5e_dma_info *dma_info) +void mlx5e_page_release(struct mlx5e_rq *rq, struct mlx5e_dma_info *dma_info, + bool recycle) { + if (likely(recycle) && mlx5e_rx_cache_put(rq, dma_info)) + return; + dma_unmap_page(rq->pdev, dma_info->addr, PAGE_SIZE, DMA_FROM_DEVICE); put_page(dma_info->page); } @@ -362,7 +409,7 @@ err_unmap: struct mlx5e_dma_info *dma_info = &wi->umr.dma_info[i]; page_ref_sub(dma_info->page, pg_strides); - mlx5e_page_release(rq, dma_info); + mlx5e_page_release(rq, dma_info, true); } return err; @@ -377,7 +424,7 @@ void mlx5e_free_rx_mpwqe(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi) struct mlx5e_dma_info *dma_info = &wi->umr.dma_info[i]; page_ref_sub(dma_info->page, pg_strides - wi->skbs_frags[i]); - mlx5e_page_release(rq, dma_info); + mlx5e_page_release(rq, dma_info, true); } } diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h index 1f56543feb63..6af8d79e8c2a 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h @@ -76,6 +76,10 @@ struct mlx5e_sw_stats { u64 rx_buff_alloc_err; u64 rx_cqe_compress_blks; u64 rx_cqe_compress_pkts; + u64 rx_cache_reuse; + u64 rx_cache_full; + u64 rx_cache_empty; + u64 rx_cache_busy; /* Special handling counters */ u64 link_down_events_phy; @@ -107,6 +111,10 @@ static const struct counter_desc sw_stats_desc[] = { { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_buff_alloc_err) }, { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cqe_compress_blks) }, { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cqe_compress_pkts) }, + { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_reuse) }, + { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_full) }, + { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_empty) }, + { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, rx_cache_busy) }, { MLX5E_DECLARE_STAT(struct mlx5e_sw_stats, link_down_events_phy) }, }; @@ -275,6 +283,10 @@ struct mlx5e_rq_stats { u64 buff_alloc_err; u64 cqe_compress_blks; u64 cqe_compress_pkts; + u64 cache_reuse; + u64 cache_full; + u64 cache_empty; + u64 cache_busy; }; static const struct counter_desc rq_stats_desc[] = { @@ -290,6 +302,10 @@ static const struct counter_desc rq_stats_desc[] = { { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, buff_alloc_err) }, { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cqe_compress_blks) }, { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cqe_compress_pkts) }, + { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_reuse) }, + { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_full) }, + { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_empty) }, + { MLX5E_DECLARE_RX_STAT(struct mlx5e_rq_stats, cache_busy) }, }; struct mlx5e_sq_stats {