From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roland Dreier <rdreier@cisco.com>
Subject: [ofa-general] Re: [PATCH 17/21] RDS/IB: Receive datagrams via IB
Date: Thu, 29 Jan 2009 13:47:03 -0800
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To: Olaf Kirch <okir@suse.de>
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 > > > This is racy.  You check if you're at the limit, do the allocation, and
 > > > then increment the atomic rds_ib_allocation count.  So many threads can
 > > > pass the atomic_read() test and then take you over the limit.  If you
 > > > want to make it safe then you could do atomic_inc_return() and check if
 > > > that took you over the limit.
 > >
 > > Woah, yup, thanks.
 > 
 > The refill code used to be single-threaded; and I think it still is. So
 > this can't race I think

So you don't need the atomic op at all?

 - R.