tree d354c2be9e3bedb62886a87377efe8d53fbde07d
parent dc6455a71c7fc5117977e197f67f71b49f27baba
author Manish Chopra <manish.chopra@cavium.com> 1522157681 -0700
committer David S. Miller <davem@davemloft.net> 1522170706 -0400

qede: Fix barrier usage after tx doorbell write.

Since commit c5ad119fb6c09b0297446be05bd66602fa564758
("net: sched: pfifo_fast use skb_array") driver is exposed
to an issue where it is hitting NULL skbs while handling TX
completions. Driver uses mmiowb() to flush the writes to the
doorbell bar which is a write-combined bar, however on x86
mmiowb() does not flush the write combined buffer.

This patch fixes this problem by replacing mmiowb() with wmb()
after the write combined doorbell write so that writes are
flushed and synchronized from more than one processor.

V1->V2:
-------
This patch was marked as "superseded" in patchwork.
(Not really sure for what reason).Resending it as v2.

Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: Manish Chopra <manish.chopra@cavium.com>

Signed-off-by: David S. Miller <davem@davemloft.net>