summaryrefslogtreecommitdiff
path: root/net/core
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2025-11-16 20:27:17 +0000
committerJakub Kicinski <kuba@kernel.org>2025-11-18 18:25:47 -0800
commit21664814b89e1268bc48e9f641b813746a7dbaae (patch)
treedc0c9b7fd978032be974648c29329e2f3b865d5c /net/core
parent294e63825966319e815e469931cfbfc437004d0f (diff)
net: use napi_skb_cache even in process context
This is a followup of commit e20dfbad8aab ("net: fix napi_consume_skb() with alien skbs"). Now the per-cpu napi_skb_cache is populated from TX completion path, we can make use of this cache, especially for cpus not used from a driver NAPI poll (primary user of napi_cache). We can use the napi_skb_cache only if current context is not from hard irq. With this patch, I consistently reach 130 Mpps on my UDP tx stress test and reduce SLUB spinlock contention to smaller values. Note there is still some SLUB contention for skb->head allocations. I had to tune /sys/kernel/slab/skbuff_small_head/cpu_partial and /sys/kernel/slab/skbuff_small_head/min_partial depending on the platform taxonomy. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20251116202717.1542829-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/core')
-rw-r--r--net/core/skbuff.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 8a0a4ca7fa5d..9feea830a4db 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -666,7 +666,12 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
skb = napi_skb_cache_get(true);
if (unlikely(!skb))
return NULL;
+ } else if (!in_hardirq() && !irqs_disabled()) {
+ local_bh_disable();
+ skb = napi_skb_cache_get(false);
+ local_bh_enable();
}
+
if (!skb) {
fallback:
skb = kmem_cache_alloc_node(cache, gfp_mask & ~GFP_DMA, node);