From: Ophir Munk Date: Mon, 14 May 2018 22:26:27 +0000 (+0000) Subject: net/tap: fix isolation mode toggling X-Git-Url: http://git.droids-corp.org/?p=dpdk.git;a=commitdiff_plain;h=2ef1c0da894a9534d41475b8240cff1d04e79fdf net/tap: fix isolation mode toggling Running testpmd command "flow isolae 0" (i.e. disabling flow isolation) followed by command "flow isolate 1" (i.e. enabling flow isolation) may result in a TAP error: PMD: Kernel refused TC filter rule creation (17): File exists Root cause analysis: when disabling flow isolation we keep the local rule to redirect packets on TX (TAP_REMOTE_TX index) while we add it again when enabling flow isolation. As a result this rule is added two times in a row which results in "File exists" error. The fix is to identify the "File exists" error and silently ignore it. Another issue occurs when enabling isolation mode several times in a row in which case the same tc rules are added consecutively and rte_flow structs are added to a linked list before removing the previous rte_flow structs. The fix is to act upon isolation mode command only when there is a change from "0" to "1" (or vice versa). Fixes: f503d2694825 ("net/tap: support flow API isolated mode") Cc: stable@dpdk.org Reviewed-by: Raslan Darawsheh Signed-off-by: Ophir Munk Acked-by: Keith Wiles --- diff --git a/drivers/net/tap/tap_flow.c b/drivers/net/tap/tap_flow.c index aab9eefe1c..6b60e6dc54 100644 --- a/drivers/net/tap/tap_flow.c +++ b/drivers/net/tap/tap_flow.c @@ -1568,10 +1568,14 @@ tap_flow_isolate(struct rte_eth_dev *dev, { struct pmd_internals *pmd = dev->data->dev_private; + /* normalize 'set' variable to contain 0 or 1 values */ if (set) - pmd->flow_isolate = 1; - else - pmd->flow_isolate = 0; + set = 1; + /* if already in the right isolation mode - nothing to do */ + if ((set ^ pmd->flow_isolate) == 0) + return 0; + /* mark the isolation mode for tap_flow_implicit_create() */ + pmd->flow_isolate = set; /* * If netdevice is there, setup appropriate flow rules immediately. * Otherwise it will be set when bringing up the netdevice (tun_alloc). @@ -1579,20 +1583,20 @@ tap_flow_isolate(struct rte_eth_dev *dev, if (!pmd->rxq[0].fd) return 0; if (set) { - struct rte_flow *flow; + struct rte_flow *remote_flow; while (1) { - flow = LIST_FIRST(&pmd->implicit_flows); - if (!flow) + remote_flow = LIST_FIRST(&pmd->implicit_flows); + if (!remote_flow) break; /* * Remove all implicit rules on the remote. * Keep the local rule to redirect packets on TX. * Keep also the last implicit local rule: ISOLATE. */ - if (flow->msg.t.tcm_ifindex == pmd->if_index) + if (remote_flow->msg.t.tcm_ifindex == pmd->if_index) break; - if (tap_flow_destroy_pmd(pmd, flow, NULL) < 0) + if (tap_flow_destroy_pmd(pmd, remote_flow, NULL) < 0) goto error; } /* Switch the TC rule according to pmd->flow_isolate */ @@ -1739,8 +1743,8 @@ int tap_flow_implicit_create(struct pmd_internals *pmd, } err = tap_nl_recv_ack(pmd->nlsk_fd); if (err < 0) { - /* Silently ignore re-entering remote promiscuous rule */ - if (errno == EEXIST && idx == TAP_REMOTE_PROMISC) + /* Silently ignore re-entering existing rule */ + if (errno == EEXIST) goto success; TAP_LOG(ERR, "Kernel refused TC filter rule creation (%d): %s",