From 6ec7be9a2d2b09815f69fc2183ec31857eaa6e27 Mon Sep 17 00:00:00 2001 From: Kal Conley Date: Sun, 23 Apr 2023 20:01:56 +0200 Subject: [PATCH] xsk: Use pool->dma_pages to check for DMA Compare pool->dma_pages instead of pool->dma_pages_cnt to check for an active DMA mapping. pool->dma_pages needs to be read anyway to access the map so this compiles to more efficient code. Signed-off-by: Kal Conley Signed-off-by: Daniel Borkmann Reviewed-by: Xuan Zhuo Acked-by: Magnus Karlsson Link: https://lore.kernel.org/bpf/20230423180157.93559-1-kal.conley@dectris.com --- include/net/xsk_buff_pool.h | 2 +- net/xdp/xsk_buff_pool.c | 7 ++++--- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/include/net/xsk_buff_pool.h b/include/net/xsk_buff_pool.h index d318c76..a8d7b8a 100644 --- a/include/net/xsk_buff_pool.h +++ b/include/net/xsk_buff_pool.h @@ -180,7 +180,7 @@ static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, if (likely(!cross_pg)) return false; - return pool->dma_pages_cnt && + return pool->dma_pages && !(pool->dma_pages[addr >> PAGE_SHIFT] & XSK_NEXT_PG_CONTIG_MASK); } diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c index b2df1e0..26f6d30 100644 --- a/net/xdp/xsk_buff_pool.c +++ b/net/xdp/xsk_buff_pool.c @@ -350,7 +350,7 @@ void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs) { struct xsk_dma_map *dma_map; - if (pool->dma_pages_cnt == 0) + if (!pool->dma_pages) return; dma_map = xp_find_dma_map(pool); @@ -364,6 +364,7 @@ void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs) __xp_dma_unmap(dma_map, attrs); kvfree(pool->dma_pages); + pool->dma_pages = NULL; pool->dma_pages_cnt = 0; pool->dev = NULL; } @@ -503,7 +504,7 @@ static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool) if (pool->unaligned) { xskb = pool->free_heads[--pool->free_heads_cnt]; xp_init_xskb_addr(xskb, pool, addr); - if (pool->dma_pages_cnt) + if (pool->dma_pages) xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr); } else { xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)]; @@ -569,7 +570,7 @@ static u32 xp_alloc_new_from_fq(struct xsk_buff_pool *pool, struct xdp_buff **xd if (pool->unaligned) { xskb = pool->free_heads[--pool->free_heads_cnt]; xp_init_xskb_addr(xskb, pool, addr); - if (pool->dma_pages_cnt) + if (pool->dma_pages) xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr); } else { xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)]; -- 2.7.4