netdev - [PATCH v2] myri10ge: remove an unneeded NULL check

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Date:   Sun, 20 Mar 2022 12:44:57 +0800
From:   Xiaomeng Tong <xiam0nd.tong@...il.com>
To:     christopher.lee@...i.com
Cc:     davem@...emloft.net, kuba@...nel.org, pabeni@...hat.com,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        jakobkoschel@...il.com, Xiaomeng Tong <xiam0nd.tong@...il.com>
Subject: [PATCH v2] myri10ge: remove an unneeded NULL check

The define of skb_list_walk_safe(first, skb, next_skb) is:
  for ((skb) = (first), (next_skb) = (skb) ? (skb)->next : NULL; (skb);  \
     (skb) = (next_skb), (next_skb) = (skb) ? (skb)->next : NULL)

Thus, if the 'segs' passed as 'first' into the skb_list_walk_safe is NULL,
the loop will exit immediately. In other words, it can be sure the 'segs'
is non-NULL when we run inside the loop. So just remove the unnecessary
NULL check. Also remove the unneeded assignmnets.

Signed-off-by: Xiaomeng Tong <xiam0nd.tong@...il.com>
---
changes since v1:
 - remove the unneeded assignmnets.

v1: https://lore.kernel.org/lkml/20220319052350.26535-1-xiam0nd.tong@gmail.com/
---
 drivers/net/ethernet/myricom/myri10ge/myri10ge.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
index 50ac3ee2577a..071657e3dba8 100644
--- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
+++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
@@ -2903,12 +2903,8 @@ static netdev_tx_t myri10ge_sw_tso(struct sk_buff *skb,
 		status = myri10ge_xmit(curr, dev);
 		if (status != 0) {
 			dev_kfree_skb_any(curr);
-			if (segs != NULL) {
-				curr = segs;
-				segs = next;
-				curr->next = NULL;
-				dev_kfree_skb_any(segs);
-			}
+			segs->next = NULL;
+			dev_kfree_skb_any(next);
 			goto drop;
 		}
 	}
-- 
2.17.1