From 6b083650a37318112fb60c65fbb6070584f53d93 Mon Sep 17 00:00:00 2001 From: Maciej Fijalkowski Date: Wed, 4 Sep 2024 18:28:08 +0200 Subject: [PATCH] xsk: Bump xsk_queue::queue_empty_descs in xp_can_alloc() We have STAT_FILL_EMPTY test case in xskxceiver that tries to process traffic with fill queue being empty which currently fails for zero copy ice driver after it started to use xsk_buff_can_alloc() API. That is because xsk_queue::queue_empty_descs is currently only increased from alloc APIs and right now if driver sees that xsk_buff_pool will be unable to provide the requested count of buffers, it bails out early, skipping calls to xsk_buff_alloc{_batch}(). Mentioned statistic should be handled in xsk_buff_can_alloc() from the very beginning, so let's add this logic now. Do it by open coding xskq_cons_has_entries() and bumping queue_empty_descs in the middle when fill queue currently has no entries. Signed-off-by: Maciej Fijalkowski Signed-off-by: Daniel Borkmann Acked-by: Magnus Karlsson Link: https://lore.kernel.org/bpf/20240904162808.249160-1-maciej.fijalkowski@intel.com --- net/xdp/xsk_buff_pool.c | 10 +++++++++- net/xdp/xsk_queue.h | 5 ----- 2 files changed, 9 insertions(+), 6 deletions(-) diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c index c0e0204b9630..dad7849c1b75 100644 --- a/net/xdp/xsk_buff_pool.c +++ b/net/xdp/xsk_buff_pool.c @@ -656,9 +656,17 @@ EXPORT_SYMBOL(xp_alloc_batch); bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count) { + u32 req_count, avail_count; + if (pool->free_list_cnt >= count) return true; - return xskq_cons_has_entries(pool->fq, count - pool->free_list_cnt); + + req_count = count - pool->free_list_cnt; + avail_count = xskq_cons_nb_entries(pool->fq, req_count); + if (!avail_count) + pool->fq->queue_empty_descs++; + + return avail_count >= req_count; } EXPORT_SYMBOL(xp_can_alloc); diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h index 6f2d1621c992..406b20dfee8d 100644 --- a/net/xdp/xsk_queue.h +++ b/net/xdp/xsk_queue.h @@ -306,11 +306,6 @@ static inline u32 xskq_cons_nb_entries(struct xsk_queue *q, u32 max) return entries >= max ? max : entries; } -static inline bool xskq_cons_has_entries(struct xsk_queue *q, u32 cnt) -{ - return xskq_cons_nb_entries(q, cnt) >= cnt; -} - static inline bool xskq_cons_peek_addr_unchecked(struct xsk_queue *q, u64 *addr) { if (q->cached_prod == q->cached_cons)