From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ravikiran G Thirumalai Date: Mon, 17 Apr 2006 22:02:38 +0000 Subject: Re: [PATCH 00/05] robust per_cpu allocation for modules Message-Id: <20060417220238.GD3945@localhost.localdomain> List-Id: References: <1145049535.1336.128.camel@localhost.localdomain> <4440855A.7040203@yahoo.com.au> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Christoph Lameter Cc: Nick Piggin , Steven Rostedt , LKML , Andrew Morton , Linus Torvalds , Ingo Molnar , Thomas Gleixner , Andi Kleen , Martin Mares , bjornw@axis.com, schwidefsky@de.ibm.com, benedict.gaster@superh.com, lethal@linux-sh.org, Chris Zankel , Marc Gauthier , Joe Taylor , David Mosberger-Tang , rth@twiddle.net, spyro@f2s.com, starvik@axis.com, tony.luck@intel.com, linux-ia64@vger.kernel.org, ralf@linux-mips.org, linux-mips@linux-mips.org, grundler@parisc-linux.org, parisc-linux@parisc-linux.org, linuxppc-dev@ozlabs.org, paulus@samba.org, linux390@de.ibm.com, davem@davemloft.net On Mon, Apr 17, 2006 at 09:55:02AM -0700, Christoph Lameter wrote: > On Sat, 15 Apr 2006, Nick Piggin wrote: > > > If I'm following you correctly, this adds another dependent load > > to a per-CPU data access, and from memory that isn't node-affine. > > I am also concerned about that. Kiran has a patch to avoid allocpercpu > having to go through one level of indirection that I guess would no > longer work with this scheme. The alloc_percpu reimplementation would work regardless of changes to static per-cpu areas. But, any extra indirection as was proposed initially is bad IMHO. > > > If so, I think people with SMP and NUMA kernels would care more > > about performance and scalability than the few k of memory this > > saves. > > Right. Me too :) Kiran