From patchwork Wed Aug 23 15:26:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Westphal X-Patchwork-Id: 13362771 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A299CA42 for ; Wed, 23 Aug 2023 15:27:46 +0000 (UTC) Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:237:300::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39F16CD9; Wed, 23 Aug 2023 08:27:45 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1qYplk-0001la-DY; Wed, 23 Aug 2023 17:27:40 +0200 From: Florian Westphal To: Cc: Paolo Abeni , "David S. Miller" , Eric Dumazet , Jakub Kicinski , , Pablo Neira Ayuso Subject: [PATCH net 6/6] netfilter: nf_tables: defer gc run if previous batch is still pending Date: Wed, 23 Aug 2023 17:26:54 +0200 Message-ID: <20230823152711.15279-7-fw@strlen.de> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230823152711.15279-1-fw@strlen.de> References: <20230823152711.15279-1-fw@strlen.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-1.7 required=5.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_BLOCKED,SPF_HELO_PASS, SPF_PASS autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org Don't queue more gc work, else we may queue the same elements multiple times. If an element is flagged as dead, this can mean that either the previous gc request was invalidated/discarded by a transaction or that the previous request is still pending in the system work queue. The latter will happen if the gc interval is set to a very low value, e.g. 1ms, and system work queue is backlogged. The sets refcount is 1 if no previous gc requeusts are queued, so add a helper for this and skip gc run if old requests are pending. Add a helper for this and skip the gc run in this case. Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API") Signed-off-by: Florian Westphal Reviewed-by: Pablo Neira Ayuso --- include/net/netfilter/nf_tables.h | 5 +++++ net/netfilter/nft_set_hash.c | 3 +++ net/netfilter/nft_set_rbtree.c | 3 +++ 3 files changed, 11 insertions(+) diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index ffcbdf08380f..dd40c75011d2 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -587,6 +587,11 @@ static inline void *nft_set_priv(const struct nft_set *set) return (void *)set->data; } +static inline bool nft_set_gc_is_pending(const struct nft_set *s) +{ + return refcount_read(&s->refs) != 1; +} + static inline struct nft_set *nft_set_container_of(const void *priv) { return (void *)priv - offsetof(struct nft_set, data); diff --git a/net/netfilter/nft_set_hash.c b/net/netfilter/nft_set_hash.c index cef5df846000..524763659f25 100644 --- a/net/netfilter/nft_set_hash.c +++ b/net/netfilter/nft_set_hash.c @@ -326,6 +326,9 @@ static void nft_rhash_gc(struct work_struct *work) nft_net = nft_pernet(net); gc_seq = READ_ONCE(nft_net->gc_seq); + if (nft_set_gc_is_pending(set)) + goto done; + gc = nft_trans_gc_alloc(set, gc_seq, GFP_KERNEL); if (!gc) goto done; diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c index f9d4c8fcbbf8..c6435e709231 100644 --- a/net/netfilter/nft_set_rbtree.c +++ b/net/netfilter/nft_set_rbtree.c @@ -611,6 +611,9 @@ static void nft_rbtree_gc(struct work_struct *work) nft_net = nft_pernet(net); gc_seq = READ_ONCE(nft_net->gc_seq); + if (nft_set_gc_is_pending(set)) + goto done; + gc = nft_trans_gc_alloc(set, gc_seq, GFP_KERNEL); if (!gc) goto done;