From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Simmons Date: Wed, 15 Jul 2020 16:45:18 -0400 Subject: [lustre-devel] [PATCH 37/37] lnet: check rtr_nid is a gateway In-Reply-To: <1594845918-29027-1-git-send-email-jsimmons@infradead.org> References: <1594845918-29027-1-git-send-email-jsimmons@infradead.org> Message-ID: <1594845918-29027-38-git-send-email-jsimmons@infradead.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org From: Amir Shehata The rtr_nid is specified for all REPLY/ACK. However it is possible for the route through the gateway specified by rtr_nid to be removed. In this case we don't want to use it. We should lookup alternative paths. This patch checks if the peer looked up is indeed a gateway. If it's not a gateway then we attempt to find another path. There is no need to fail right away. It's not a hard requirement to fail if the default rtr_nid is not valid. WC-bug-id: https://jira.whamcloud.com/browse/LU-13713 Lustre-commit: 07397a2e7473c ("LU-13713 lnet: check rtr_nid is a gateway") Signed-off-by: Amir Shehata Reviewed-on: https://review.whamcloud.com/39175 Reviewed-by: Chris Horn Reviewed-by: Serguei Smirnov Reviewed-by: Oleg Drokin Signed-off-by: James Simmons --- net/lnet/lnet/lib-move.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/net/lnet/lnet/lib-move.c b/net/lnet/lnet/lib-move.c index 234fbb5..c0dd30c 100644 --- a/net/lnet/lnet/lib-move.c +++ b/net/lnet/lnet/lib-move.c @@ -1777,6 +1777,7 @@ struct lnet_ni * struct lnet_route *last_route = NULL; struct lnet_peer_ni *lpni = NULL; struct lnet_peer_ni *gwni = NULL; + bool route_found = false; lnet_nid_t src_nid = (sd->sd_src_nid != LNET_NID_ANY) ? sd->sd_src_nid : sd->sd_best_ni ? sd->sd_best_ni->ni_nid : LNET_NID_ANY; @@ -1790,15 +1791,20 @@ struct lnet_ni * */ if (sd->sd_rtr_nid != LNET_NID_ANY) { gwni = lnet_find_peer_ni_locked(sd->sd_rtr_nid); - if (!gwni) { - CERROR("No peer NI for gateway %s\n", + if (gwni) { + gw = gwni->lpni_peer_net->lpn_peer; + lnet_peer_ni_decref_locked(gwni); + if (gw->lp_rtr_refcount) { + local_lnet = LNET_NIDNET(sd->sd_rtr_nid); + route_found = true; + } + } else { + CWARN("No peer NI for gateway %s. Attempting to find an alternative route.\n", libcfs_nid2str(sd->sd_rtr_nid)); - return -EHOSTUNREACH; } - gw = gwni->lpni_peer_net->lpn_peer; - lnet_peer_ni_decref_locked(gwni); - local_lnet = LNET_NIDNET(sd->sd_rtr_nid); - } else { + } + + if (!route_found) { /* we've already looked up the initial lpni using dst_nid */ lpni = sd->sd_best_lpni; /* the peer tree must be in existence */ -- 1.8.3.1