From patchwork Tue Jul 18 18:03:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 13317574 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 074601641B for ; Tue, 18 Jul 2023 18:03:48 +0000 (UTC) Received: from mail-yw1-x112c.google.com (mail-yw1-x112c.google.com [IPv6:2607:f8b0:4864:20::112c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 876ECB6 for ; Tue, 18 Jul 2023 11:03:46 -0700 (PDT) Received: by mail-yw1-x112c.google.com with SMTP id 00721157ae682-577637de4beso61256757b3.0 for ; Tue, 18 Jul 2023 11:03:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1689703426; x=1692295426; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=8TR/4BkGxGVKYWleZTfiMv2J01KA2c0QwldS4cSwYrU=; b=DG/dIpKNFFlN9owucF7gcVUOPf6hcwJ8FW3l4HyL5Xg+OzmOJiaLTQQkxajJ1mSwpg 92L8LiFEPMRq5yHRfs3V5HInSFvu5MJ0o8rfjhAViIWbez9ilrY9bPxgbzMGmJl3eDSE O9g0Gb2CaPXR95SrlcJPjk8bapHgxKSwRfKUvxaoq2QQE5RGM1onCQQRfk/ASP8IV5/a mcUwu8iSyOqx8jxOTNDkJhBtetOqS2G/WDA4wW4pwWA0WiLZ9V5+Y5S85MbS25XB6GwC TGMkgTPps609jEzJFxzqNf0pMH/eLZJxZX7UnvnDSY8bWdDWiEDoe29d+b5nbSZiGY95 ha+Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689703426; x=1692295426; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8TR/4BkGxGVKYWleZTfiMv2J01KA2c0QwldS4cSwYrU=; b=JHphhPD5cmDRS0X4dSfe+xE5avUa3NGTLkDUwCOgjdZC9NwdVD+ONjvbR7Koa5p5GT KBpCGgQM+8yyb0o+cq4aVYzxy15rDAOcsvByW++eVI1Dp51mkSYCE8KhoyT23SIqJjR5 pHwHG9uXysvBzUmzLZ4vr3BRgB/CQma0OvVAVU34P8jV+Ruspz6xdUtRJOsPiHWlyLUk Oix3VB2Gu9paxQN1GM6ZnSUW4dezKRLXszc0mxLUvgKc5xQ6codboCdzohxCnF4tOahI aalqMf4GKA+wT7Asrl3WTdgf/qBM7R69k4KgvQ5+kyYgaPouOcFf62int61zMvvtwLvR WKKw== X-Gm-Message-State: ABy/qLZJaHJkZCb2eJlKuqIShqJXio/hmFbFsQsNItaitJO8be1Ynfnr 3KtS1Ghbc7Q4JtxoSlWP1v0= X-Google-Smtp-Source: APBJJlGzTq8bmVqOTYMWhUw0jPyIuwa0tpFMoEK+YdvRDinse5dTgfh/i9K/CFi9qPvtjRjaHdUNwA== X-Received: by 2002:a81:7505:0:b0:573:7f55:a40e with SMTP id q5-20020a817505000000b005737f55a40emr400866ywc.49.1689703425678; Tue, 18 Jul 2023 11:03:45 -0700 (PDT) Received: from kickker.attlocal.net ([2600:1700:6cf8:1240:770d:e789:cf56:fb43]) by smtp.gmail.com with ESMTPSA id d3-20020a81d343000000b00577044eb00esm579121ywl.21.2023.07.18.11.03.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 11:03:45 -0700 (PDT) From: Kui-Feng Lee X-Google-Original-From: Kui-Feng Lee To: dsahern@kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, martin.lau@linux.dev, kernel-team@meta.com, yhs@meta.com Cc: Kui-Feng Lee Subject: [PATCH net-next v2 1/2] net/ipv6: Remove expired routes with a separated list of routes. Date: Tue, 18 Jul 2023 11:03:20 -0700 Message-Id: <20230718180321.294721-2-kuifeng@meta.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230718180321.294721-1-kuifeng@meta.com> References: <20230718180321.294721-1-kuifeng@meta.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham 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 FIB6 GC walks trees of fib6_tables to remove expired routes. Walking a tree can be expensive if the number of routes in a table is big, even if most of them are permanent. Checking routes in a separated list of routes having expiration will avoid this potential issue. Signed-off-by: Kui-Feng Lee --- include/net/ip6_fib.h | 65 ++++++++++++++++++++++++++++++++++--------- net/ipv6/ip6_fib.c | 53 ++++++++++++++++++++++++++++++++--- net/ipv6/route.c | 6 ++-- 3 files changed, 104 insertions(+), 20 deletions(-) diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h index 05e6f756feaf..e6f4d986fb63 100644 --- a/include/net/ip6_fib.h +++ b/include/net/ip6_fib.h @@ -179,6 +179,9 @@ struct fib6_info { refcount_t fib6_ref; unsigned long expires; + + struct hlist_node gc_link; + struct dst_metrics *fib6_metrics; #define fib6_pmtu fib6_metrics->metrics[RTAX_MTU-1] @@ -247,19 +250,6 @@ static inline bool fib6_requires_src(const struct fib6_info *rt) return rt->fib6_src.plen > 0; } -static inline void fib6_clean_expires(struct fib6_info *f6i) -{ - f6i->fib6_flags &= ~RTF_EXPIRES; - f6i->expires = 0; -} - -static inline void fib6_set_expires(struct fib6_info *f6i, - unsigned long expires) -{ - f6i->expires = expires; - f6i->fib6_flags |= RTF_EXPIRES; -} - static inline bool fib6_check_expired(const struct fib6_info *f6i) { if (f6i->fib6_flags & RTF_EXPIRES) @@ -267,6 +257,11 @@ static inline bool fib6_check_expired(const struct fib6_info *f6i) return false; } +static inline bool fib6_has_expires(const struct fib6_info *f6i) +{ + return f6i->fib6_flags & RTF_EXPIRES; +} + /* Function to safely get fn->fn_sernum for passed in rt * and store result in passed in cookie. * Return true if we can get cookie safely @@ -388,6 +383,7 @@ struct fib6_table { struct inet_peer_base tb6_peers; unsigned int flags; unsigned int fib_seq; + struct hlist_head tb6_gc_hlist; /* GC candidates */ #define RT6_TABLE_HAS_DFLT_ROUTER BIT(0) }; @@ -504,6 +500,49 @@ void fib6_gc_cleanup(void); int fib6_init(void); +/* fib6_info must be locked by the caller, and fib6_info->fib6_table can be + * NULL. + */ +static inline void fib6_set_expires_locked(struct fib6_info *f6i, unsigned long expires) +{ + struct fib6_table *tb6; + + tb6 = f6i->fib6_table; + f6i->expires = expires; + if (tb6 && !fib6_has_expires(f6i)) + hlist_add_head(&f6i->gc_link, &tb6->tb6_gc_hlist); + f6i->fib6_flags |= RTF_EXPIRES; +} + +/* fib6_info must be locked by the caller, and fib6_info->fib6_table can be + * NULL. If fib6_table is NULL, the fib6_info will no be inserted into the + * list of GC candidates until it is inserted into a table. + */ +static inline void fib6_set_expires(struct fib6_info *f6i, unsigned long expires) +{ + spin_lock_bh(&f6i->fib6_table->tb6_lock); + fib6_set_expires_locked(f6i, expires); + spin_unlock_bh(&f6i->fib6_table->tb6_lock); +} + +static inline void fib6_clean_expires_locked(struct fib6_info *f6i) +{ + struct fib6_table *tb6; + + tb6 = f6i->fib6_table; + if (tb6 && fib6_has_expires(f6i)) + hlist_del_init(&f6i->gc_link); + f6i->fib6_flags &= ~RTF_EXPIRES; + f6i->expires = 0; +} + +static inline void fib6_clean_expires(struct fib6_info *f6i) +{ + spin_lock_bh(&f6i->fib6_table->tb6_lock); + fib6_clean_expires_locked(f6i); + spin_unlock_bh(&f6i->fib6_table->tb6_lock); +} + struct ipv6_route_iter { struct seq_net_private p; struct fib6_walker w; diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index bac768d36cc1..a4422d513d4d 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -160,6 +160,8 @@ struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh) INIT_LIST_HEAD(&f6i->fib6_siblings); refcount_set(&f6i->fib6_ref, 1); + INIT_HLIST_NODE(&f6i->gc_link); + return f6i; } @@ -246,6 +248,7 @@ static struct fib6_table *fib6_alloc_table(struct net *net, u32 id) net->ipv6.fib6_null_entry); table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; inet_peer_base_init(&table->tb6_peers); + INIT_HLIST_HEAD(&table->tb6_gc_hlist); } return table; @@ -1057,6 +1060,11 @@ static void fib6_purge_rt(struct fib6_info *rt, struct fib6_node *fn, lockdep_is_held(&table->tb6_lock)); } } + + if (fib6_has_expires(rt)) { + hlist_del_init(&rt->gc_link); + rt->fib6_flags &= ~RTF_EXPIRES; + } } /* @@ -1118,9 +1126,9 @@ static int fib6_add_rt2node(struct fib6_node *fn, struct fib6_info *rt, if (!(iter->fib6_flags & RTF_EXPIRES)) return -EEXIST; if (!(rt->fib6_flags & RTF_EXPIRES)) - fib6_clean_expires(iter); + fib6_clean_expires_locked(iter); else - fib6_set_expires(iter, rt->expires); + fib6_set_expires_locked(iter, rt->expires); if (rt->fib6_pmtu) fib6_metric_set(iter, RTAX_MTU, @@ -1480,6 +1488,9 @@ int fib6_add(struct fib6_node *root, struct fib6_info *rt, list_add(&rt->nh_list, &rt->nh->f6i_list); __fib6_update_sernum_upto_root(rt, fib6_new_sernum(info->nl_net)); fib6_start_gc(info->nl_net, rt); + + if (fib6_has_expires(rt)) + hlist_add_head(&rt->gc_link, &table->tb6_gc_hlist); } out: @@ -2295,7 +2306,7 @@ static int fib6_age(struct fib6_info *rt, void *arg) * Routes are expired even if they are in use. */ - if (rt->fib6_flags & RTF_EXPIRES && rt->expires) { + if (fib6_has_expires(rt) && rt->expires) { if (time_after(now, rt->expires)) { RT6_TRACE("expiring %p\n", rt); return -1; @@ -2312,6 +2323,40 @@ static int fib6_age(struct fib6_info *rt, void *arg) return 0; } +static void fib6_gc_table(struct net *net, + struct fib6_table *tb6, + void *arg) +{ + struct fib6_info *rt; + struct hlist_node *n; + struct nl_info info = { + .nl_net = net, + .skip_notify = false, + }; + + hlist_for_each_entry_safe(rt, n, &tb6->tb6_gc_hlist, gc_link) + if (fib6_age(rt, arg) == -1) + fib6_del(rt, &info); +} + +static void fib6_gc_all(struct net *net, void *arg) +{ + struct fib6_table *table; + struct hlist_head *head; + unsigned int h; + + rcu_read_lock(); + for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { + head = &net->ipv6.fib_table_hash[h]; + hlist_for_each_entry_rcu(table, head, tb6_hlist) { + spin_lock_bh(&table->tb6_lock); + fib6_gc_table(net, table, arg); + spin_unlock_bh(&table->tb6_lock); + } + } + rcu_read_unlock(); +} + void fib6_run_gc(unsigned long expires, struct net *net, bool force) { struct fib6_gc_args gc_args; @@ -2327,7 +2372,7 @@ void fib6_run_gc(unsigned long expires, struct net *net, bool force) net->ipv6.sysctl.ip6_rt_gc_interval; gc_args.more = 0; - fib6_clean_all(net, fib6_age, &gc_args); + fib6_gc_all(net, &gc_args); now = jiffies; net->ipv6.ip6_rt_last_gc = now; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 64e873f5895f..a69083563689 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3760,10 +3760,10 @@ static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg, rt->dst_nocount = true; if (cfg->fc_flags & RTF_EXPIRES) - fib6_set_expires(rt, jiffies + - clock_t_to_jiffies(cfg->fc_expires)); + fib6_set_expires_locked(rt, jiffies + + clock_t_to_jiffies(cfg->fc_expires)); else - fib6_clean_expires(rt); + fib6_clean_expires_locked(rt); if (cfg->fc_protocol == RTPROT_UNSPEC) cfg->fc_protocol = RTPROT_BOOT; From patchwork Tue Jul 18 18:03:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 13317575 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 28A101641A for ; Tue, 18 Jul 2023 18:03:48 +0000 (UTC) Received: from mail-yw1-x112f.google.com (mail-yw1-x112f.google.com [IPv6:2607:f8b0:4864:20::112f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B9E1EA1 for ; Tue, 18 Jul 2023 11:03:47 -0700 (PDT) Received: by mail-yw1-x112f.google.com with SMTP id 00721157ae682-5703d12ab9aso63845617b3.2 for ; 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Wait for a few seconds to make sure they are removed correctly. Signed-off-by: Kui-Feng Lee --- tools/testing/selftests/net/fib_tests.sh | 49 +++++++++++++++++++++++- 1 file changed, 48 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh index 35d89dfa6f11..55bc6897513a 100755 --- a/tools/testing/selftests/net/fib_tests.sh +++ b/tools/testing/selftests/net/fib_tests.sh @@ -9,7 +9,7 @@ ret=0 ksft_skip=4 # all tests in this script. Can be overridden with -t option -TESTS="unregister down carrier nexthop suppress ipv6_notify ipv4_notify ipv6_rt ipv4_rt ipv6_addr_metric ipv4_addr_metric ipv6_route_metrics ipv4_route_metrics ipv4_route_v6_gw rp_filter ipv4_del_addr ipv4_mangle ipv6_mangle ipv4_bcast_neigh" +TESTS="unregister down carrier nexthop suppress ipv6_notify ipv4_notify ipv6_rt ipv4_rt ipv6_addr_metric ipv4_addr_metric ipv6_route_metrics ipv4_route_metrics ipv4_route_v6_gw rp_filter ipv4_del_addr ipv4_mangle ipv6_mangle ipv4_bcast_neigh fib6_gc_test" VERBOSE=0 PAUSE_ON_FAIL=no @@ -747,6 +747,52 @@ fib_notify_test() cleanup &> /dev/null } +fib6_gc_test() +{ + setup + + echo + echo "Fib6 garbage collection test" + set -e + + OLD_INTERVAL=$(sysctl -n net.ipv6.route.gc_interval) + # Check expiration of routes every 3 seconds (GC) + $NS_EXEC sysctl -wq net.ipv6.route.gc_interval=3 + + $IP link add dummy_10 type dummy + $IP link set dev dummy_10 up + $IP -6 address add 2001:10::1/64 dev dummy_10 + + for i in 0 1 2 3 4 5 6 7 8 9; do + # Expire route after 2 seconds + $IP -6 route add 2001:20::1$i \ + via 2001:10::2 dev dummy_10 expires 2 + done + N_EXP=$($IP -6 route list |grep expires|wc -l) + if [ $N_EXP -ne 10 ]; then + echo "FAIL: expected 10 routes with expires, got $N_EXP" + ret=1 + else + sleep 4 + N_EXP_s20=$($IP -6 route list |grep expires|wc -l) + + if [ $N_EXP_s20 -ne 0 ]; then + echo "FAIL: expected 0 routes with expires, got $N_EXP_s20" + ret=1 + else + ret=0 + fi + fi + + set +e + + log_test $ret 0 "ipv6 route garbage collection" + + sysctl -wq net.ipv6.route.gc_interval=$OLD_INTERVAL + + cleanup &> /dev/null +} + fib_suppress_test() { echo @@ -2217,6 +2263,7 @@ do ipv4_mangle) ipv4_mangle_test;; ipv6_mangle) ipv6_mangle_test;; ipv4_bcast_neigh) ipv4_bcast_neigh_test;; + fib6_gc_test|ipv6_gc) fib6_gc_test;; help) echo "Test names: $TESTS"; exit 0;; esac