From mboxrd@z Thu Jan 1 00:00:00 1970 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 CDB7E6110 for ; Wed, 9 Aug 2023 07:06:24 +0000 (UTC) Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0276A210A for ; Wed, 9 Aug 2023 00:06:15 -0700 (PDT) Received: from compute6.internal (compute6.nyi.internal [10.202.2.47]) by mailout.nyi.internal (Postfix) with ESMTP id D9EEB5C00F3; Wed, 9 Aug 2023 03:06:12 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute6.internal (MEProxy); Wed, 09 Aug 2023 03:06:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1691564772; x=1691651172; bh=lEIVIdiadlMOQ znaYEIr+e2Jc/zCgbo4ipBOCBnglh4=; b=MzJB1xrr9O3tKuwzwry8M9bZpzRl9 Lwl+2Pp0XnKqEMhuJPLXDVryq7wjXUq8DMHSLSdcstcq4winqROMySq07Uqn/wSB 7c8ZhaMhk0Eto/U5iA2Y35zEfOe1TPMfp8/8pQJmjIrMrQ2KkoQbNILvz5vwR9bU LOHIOfZbrZZ+rtFvTWX/zWXmQrnWc+EzpR5RM2gp4qlXxTnwAT0HQQA9MDvkAJgd zgAv8R9i3AfJ5eBuK2PAcqEnZ8wd0Qhz7xcevEN8yIjsczzGqjYsEDXe5WqQz+ta 9iT2Sdr04EXbzUL6Df2QVDp7eDf3k2KeDnH9Qi7T77oVvOc4GzB9IXPgQ== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedviedrleefgdduudefucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvfevuffkfhggtggujgesthdtredttddtvdenucfhrhhomhepkfguohcu ufgthhhimhhmvghluceoihguohhstghhsehiughoshgthhdrohhrgheqnecuggftrfgrth htvghrnhepvddufeevkeehueegfedtvdevfefgudeifeduieefgfelkeehgeelgeejjeeg gefhnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepih guohhstghhsehiughoshgthhdrohhrgh X-ME-Proxy: Feedback-ID: i494840e7:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 9 Aug 2023 03:06:11 -0400 (EDT) Date: Wed, 9 Aug 2023 10:06:07 +0300 From: Ido Schimmel To: Hangbin Liu Cc: David Ahern , Stephen Hemminger , netdev@vger.kernel.org, "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Thomas Haller Subject: Re: [PATCH net-next] ipv4/fib: send RTM_DELROUTE notify when flush fib Message-ID: References: <20230718080044.2738833-1-liuhangbin@gmail.com> <20230718085814.4301b9dd@hermes.local> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL, SPF_HELO_PASS,SPF_NONE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Fri, Aug 04, 2023 at 04:09:08PM +0800, Hangbin Liu wrote: > I reconsidered this issue this week. As we can't get the device status in > fib_table_flush(). How about adding another flag to track the deleted src > entries. e.g. RTNH_F_UNRESOLVED. Which is only used in ipmr currently. > When the src route address is deleted, the route entry also could be > considered as unresolved. With this idea, the patch could be like: > > diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h > index 51c13cf9c5ae..5c41d34ab447 100644 > --- a/include/uapi/linux/rtnetlink.h > +++ b/include/uapi/linux/rtnetlink.h > @@ -420,7 +420,7 @@ struct rtnexthop { > #define RTNH_F_ONLINK 4 /* Gateway is forced on link */ > #define RTNH_F_OFFLOAD 8 /* Nexthop is offloaded */ > #define RTNH_F_LINKDOWN 16 /* carrier-down on nexthop */ > -#define RTNH_F_UNRESOLVED 32 /* The entry is unresolved (ipmr) */ > +#define RTNH_F_UNRESOLVED 32 /* The entry is unresolved (ipmr/dead src) */ > #define RTNH_F_TRAP 64 /* Nexthop is trapping packets */ > > #define RTNH_COMPARE_MASK (RTNH_F_DEAD | RTNH_F_LINKDOWN | \ I'm not sure we need to reinterpret the meaning of this uAPI flag. The FIB info structure currently looks like this: struct fib_info { struct hlist_node fib_hash; /* 0 16 */ struct hlist_node fib_lhash; /* 16 16 */ struct list_head nh_list; /* 32 16 */ struct net * fib_net; /* 48 8 */ refcount_t fib_treeref; /* 56 4 */ refcount_t fib_clntref; /* 60 4 */ /* --- cacheline 1 boundary (64 bytes) --- */ unsigned int fib_flags; /* 64 4 */ unsigned char fib_dead; /* 68 1 */ unsigned char fib_protocol; /* 69 1 */ unsigned char fib_scope; /* 70 1 */ unsigned char fib_type; /* 71 1 */ __be32 fib_prefsrc; /* 72 4 */ u32 fib_tb_id; /* 76 4 */ u32 fib_priority; /* 80 4 */ /* XXX 4 bytes hole, try to pack */ struct dst_metrics * fib_metrics; /* 88 8 */ int fib_nhs; /* 96 4 */ bool fib_nh_is_v6; /* 100 1 */ bool nh_updated; /* 101 1 */ /* XXX 2 bytes hole, try to pack */ struct nexthop * nh; /* 104 8 */ struct callback_head rcu __attribute__((__aligned__(8))); /* 112 16 */ /* --- cacheline 2 boundary (128 bytes) --- */ struct fib_nh fib_nh[]; /* 128 0 */ /* size: 128, cachelines: 2, members: 21 */ /* sum members: 122, holes: 2, sum holes: 6 */ /* forced alignments: 1 */ } __attribute__((__aligned__(8))); We can instead represent fib_nh_is_v6 and nh_updated using a single bit: diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index a378eff827c7..a91f8a28689a 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -152,8 +152,8 @@ struct fib_info { #define fib_rtt fib_metrics->metrics[RTAX_RTT-1] #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1] int fib_nhs; - bool fib_nh_is_v6; - bool nh_updated; + u8 fib_nh_is_v6:1, + nh_updated:1; struct nexthop *nh; struct rcu_head rcu; struct fib_nh fib_nh[]; And then add another bit there to mark a FIB info that is deleted because of preferred source address deletion. I suggest testing with the FIB tests in tools/testing/selftests/net/. > diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c > index 65ba18a91865..a7ef21a6d271 100644 > --- a/net/ipv4/fib_semantics.c > +++ b/net/ipv4/fib_semantics.c > @@ -1883,7 +1883,7 @@ int fib_sync_down_addr(struct net_device *dev, __be32 local) > fi->fib_tb_id != tb_id) > continue; > if (fi->fib_prefsrc == local) { > - fi->fib_flags |= RTNH_F_DEAD; > + fi->fib_flags |= (RTNH_F_DEAD | RTNH_F_UNRESOLVED); > ret++; > } > } > diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c > index 74d403dbd2b4..88c593967063 100644 > --- a/net/ipv4/fib_trie.c > +++ b/net/ipv4/fib_trie.c > @@ -2026,6 +2026,7 @@ void fib_table_flush_external(struct fib_table *tb) > int fib_table_flush(struct net *net, struct fib_table *tb, bool flush_all) > { > struct trie *t = (struct trie *)tb->tb_data; > + struct nl_info info = { .nl_net = net }; > struct key_vector *pn = t->kv; > unsigned long cindex = 1; > struct hlist_node *tmp; > @@ -2088,6 +2089,11 @@ int fib_table_flush(struct net *net, struct fib_table *tb, bool flush_all) > > fib_notify_alias_delete(net, n->key, &n->leaf, fa, > NULL); > + if (fi->fib_flags & RTNH_F_UNRESOLVED) { > + fi->fib_flags &= ~RTNH_F_UNRESOLVED; > + rtmsg_fib(RTM_DELROUTE, htonl(n->key), fa, > + KEYLENGTH - fa->fa_slen, tb->tb_id, &info, 0); > + } > hlist_del_rcu(&fa->fa_list); > fib_release_info(fa->fa_info); > alias_free_mem_rcu(fa); > > Thanks > Hangbin