From: Ben Greear <greearb@xxxxxxxxxxxxxxx>
Date: Thu, 09 Jun 2005 18:20:33 -0700
> I ran a test using pktgen to (try to) send 82kpps, 1514 byte packets between
> two ports on the tg3 NIC. It can do about 780Mbps in one direction,
> and 880Mbps in the other direction. Lots of harmless hard-start xmit errors
> reported
> (tg3 may not stop it's tx queue correctly, or maybe pktgen is screwed up since
> e1000 reports similar errors).
There is a known race on SMP with drivers using NETIF_F_LLTX that is
still not fixed. It will cause the error message to be reported from
the driver's ->hard_start_xmit() routine when you hit this race.
The e1000 driver hits the same race, it just doesn't print any
message.
You're definitely on an SMP system if you are triggering that message.
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