From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH] The VMXNET3 PMD can't receive packet
 suddenly after a lot of traffic coming in
Date: Thu, 23 Jul 2015 09:49:13 -0700
Message-ID: <20150723094913.27cc335f@urahara>
References: <1437641492-7622-1-git-send-email-mac_leehk@yahoo.com.hk>
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To: Marco Lee <mac_leehk@yahoo.com.hk>
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On Thu, 23 Jul 2015 16:51:32 +0800
Marco Lee <mac_leehk@yahoo.com.hk> wrote:

> The RX of VMXNET3 PMD will have deadlock when a lot of traffic coming in.
> The root cause is due to mbuf allocation fail in vmxnet3_post_rx_bufs() and there is no error handling when it is called
> from vmxnet3_recv_pkts(). The RXD will not have "free" mbuf for it but the counter still increment.
> Finally, no packet can be received.
> 
> This fix is allocate the mbuf first, if the allocation is failed, then reuse the old mbuf
> If the allocation is sucess, the vmxnet3_post_rx_bufs() will call vmxnet3_renew_desc()
> and RXD will be renew inside.
> 
> Signed-off-by: Marco Lee <mac_leehk@yahoo.com.hk/marco.lee@ruckuswireless.com>

Much better. I ran this patch through checkpatch and the following
things should be fixed.

WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#69: 
The root cause is due to mbuf allocation fail in vmxnet3_post_rx_bufs() and there is no error handling when it is called

WARNING: 'sucess' may be misspelled - perhaps 'success'?
#74: 
If the allocation is sucess, the vmxnet3_post_rx_bufs() will call vmxnet3_renew_desc()

WARNING: line over 80 characters
#91: FILE: drivers/net/vmxnet3/vmxnet3_rxtx.c:425:
+vmxnet3_renew_desc(vmxnet3_rx_queue_t *rxq, uint8_t ring_id,struct rte_mbuf *mbuf)

ERROR: space required after that ',' (ctx:VxV)
#91: FILE: drivers/net/vmxnet3/vmxnet3_rxtx.c:425:
+vmxnet3_renew_desc(vmxnet3_rx_queue_t *rxq, uint8_t ring_id,struct rte_mbuf *mbuf)
                                                            ^
WARNING: braces {} are not necessary for any arm of this statement
#101: FILE: drivers/net/vmxnet3/vmxnet3_rxtx.c:435:
+	if (ring->rid == 0) {
[...]
+	} else {
[...]

ERROR: space required after that ',' (ctx:VxV)
#145: FILE: drivers/net/vmxnet3/vmxnet3_rxtx.c:694:
+		vmxnet3_renew_desc(rxq, ring_idx,rep);
 		                                ^