From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id B63EF6B01AD for ; Fri, 18 Jun 2010 13:39:58 -0400 (EDT) Message-ID: <4C1BAF51.8020702@kernel.org> Date: Fri, 18 Jun 2010 19:39:29 +0200 From: Tejun Heo MIME-Version: 1.0 Subject: Re: [PATCH 1/2] percpu: make @dyn_size always mean min dyn_size in first chunk init functions References: <4C189119.5050801@kernel.org> <4C190748.7030400@kernel.org> <4C19E19D.2020802@kernel.org> <4C1BA59C.6000309@kernel.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Christoph Lameter Cc: Pekka Enberg , David Rientjes , linux-mm@kvack.org List-ID: Hello, On 06/18/2010 07:31 PM, Christoph Lameter wrote: > We need SLUB_PAGE_SHIFT * sizeof(kmem_cache_cpu). So it would be > > BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE < SLUB_PAGE_SHIFT * sizeof(struct > kmem_cache_cpu))? Yeah, something like that but I would add some buffer there for alignment and whatnot. > What is the role of SLOTS? It's allocation map. Each consecutive allocs consume one if alignment doesn't require padding but two if it does. ie. It limits how many items one can allocate. > Each kmem_cache_cpu structure is a separate percpu allocation. If it's a single item. Nothing to worry about. Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org