From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: netdev ioctl & dev_base_lock : bad idea ? Date: Thu, 09 Dec 2004 17:22:13 +1100 Message-ID: <1102573333.16495.2.camel@gaston> References: <1101458929.28048.9.camel@gaston> <20041208220642.6984519f.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: netdev@oss.sgi.com Return-path: To: "David S. Miller" In-Reply-To: <20041208220642.6984519f.davem@davemloft.net> Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On Wed, 2004-12-08 at 22:06 -0800, David S. Miller wrote: > On Fri, 26 Nov 2004 19:48:49 +1100 > Benjamin Herrenschmidt wrote: > > > I suppose there is a good reason we can't just use the rtnl_sem for > > these guys, though why isn't dev_base_lock a read/write semaphore > > instead of a spinlock ? At least on ppc, I don't think there's any > > overhead in the normal path, and this is not on a very critical path > > anyway, is it ? > > It can't be a semphore because it is taken in packet processing, > and thus softint handling, paths. Right, and I missed the fact that we did indeed take the semaphore and not the lock in the _set_ functions which is just fine, we can actually schedule.... except in set_multicast... Is there any reason we actually _need_ to get the xmit lock in this one specifically ? Ben.