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Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" skb_defer_free_flush() is becoming more important these days. Add a prefetch operation to reduce latency a bit on some platforms like AMD EPYC 7B12. On more recent cpus, a stall happens when reading skb_shinfo(). Avoiding it will require a more elaborate strategy. Signed-off-by: Eric Dumazet --- net/core/dev.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/core/dev.c b/net/core/dev.c index 537aa43edff0e4bfedb42593146cfdf7511d8c37..69515edd17bc6a157046f31b3dd343a59ae192ab 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6782,6 +6782,7 @@ static void skb_defer_free_flush(void) free_list = llist_del_all(&sdn->defer_list); llist_for_each_entry_safe(skb, next, free_list, ll_node) { + prefetch(next); napi_consume_skb(skb, 1); } } -- 2.51.2.1026.g39e6a42477-goog