netdev - [PATCH net-next] net: remove bypassed check in sch_direct

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Date:   Mon, 28 May 2018 14:36:32 -0700
From:   Song Liu <songliubraving@...com>
To:     <netdev@...r.kernel.org>
CC:     Song Liu <songliubraving@...com>, <kernel-team@...com>,
        John Fastabend <john.fastabend@...il.com>,
        Alexei Starovoitov <ast@...nel.org>,
        "David S . Miller" <davem@...emloft.net>
Subject: [PATCH net-next] net: remove bypassed check in sch_direct_xmit()

Check sch_direct_xmit() at the end of sch_direct_xmit() will be bypassed.
This is because "ret" from sch_direct_xmit() will be either NETDEV_TX_OK
or NETDEV_TX_BUSY, and only ret == NETDEV_TX_OK == 0 will reach the
condition:

    if (ret && netif_xmit_frozen_or_stopped(txq))
        return false;

This patch cleans up the code by removing  the whole condition.

For more discussion about this, please refer to
   https://marc.info/?t=152727195700008

Signed-off-by: Song Liu <songliubraving@...com>
Cc: John Fastabend <john.fastabend@...il.com>
Cc: Alexei Starovoitov <ast@...nel.org>
Cc: David S. Miller <davem@...emloft.net>
---
 net/sched/sch_generic.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 760ab1b..69078c8 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -346,9 +346,6 @@ bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 		return false;
 	}
 
-	if (ret && netif_xmit_frozen_or_stopped(txq))
-		return false;
-
 	return true;
 }
 
-- 
2.9.5