Re: [PATCH] acenic - don't spin in hard_start_xmit when ring fills

["David S. Miller" <davem@xxxxxxxxxxxxx>]

On Thu, 16 Sep 2004 16:42:06 -0700
Stephen Hemminger <shemminger@xxxxxxxx> wrote:

> NO, the bus just isn't fast enough to keep up with the number of small
> packets I am shoving at it.
> 
> You got TX_LOCKED and TX_BUSY confused. The problem is drivers that
> don't check to see if the last packet sent fills the ring and stop
> themselves.

I understand.

But that still makes this change buggy.  I believe the two choices
are:

1) Accept this spinning performance characteristic of the
   acenic driver.

or

2) Finally give up on acenic's clever lockless scheme and add
   the necessary locking + start/stop tx flow control so it
   will never have to return TX_BUSY except in absolutely
   catastrophic failure cases.