From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx159.postini.com [74.125.245.159]) by kanga.kvack.org (Postfix) with SMTP id A83F86B004D for ; Mon, 16 Jul 2012 11:56:18 -0400 (EDT) Message-ID: <1342454176.2949.14.camel@lorien2> Subject: Re: [PATCH TRIVIAL] mm: Fix build warning in kmem_cache_create() From: Shuah Khan Reply-To: shuah.khan@hp.com Date: Mon, 16 Jul 2012 09:56:16 -0600 In-Reply-To: References: <1342221125.17464.8.camel@lorien2> <1342407840.3190.5.camel@lorien2> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: David Rientjes , Pekka Enberg , glommer@parallels.com, js1304@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, shuahkhan@gmail.com On Mon, 2012-07-16 at 09:17 -0500, Christoph Lameter wrote: > On Mon, 16 Jul 2012, David Rientjes wrote: > > > On Sun, 15 Jul 2012, Shuah Khan wrote: > > > > > I can work on reshuffling the code. Do have a question though. This > > > following sanity check is currently done only when CONFIG_DEBUG_VM is > > > defined. However, it does appear to be something that is that should be > > > checked even in regular path. > > > > > > struct kmem_cache *kmem_cache_create(const char *name, size_t size, > > > size_t align, > > > unsigned long flags, void (*ctor)(void *)) > > > { > > > struct kmem_cache *s = NULL; > > > > > > #ifdef CONFIG_DEBUG_VM > > > if (!name || in_interrupt() || size < sizeof(void *) || > > > size > KMALLOC_MAX_SIZE) { > > > printk(KERN_ERR "kmem_cache_create(%s) integrity check" > > > " failed\n", name); > > > goto out; > > > } > > > #endif > > > > > > > Agreed, this shouldn't depend on CONFIG_DEBUG_VM. > > These checks are useless for regular kernel operations. They are > only useful when developing code and should only be enabled during > development. There is no point in testing the size and the name which are > typically constant when a slab is created with a stable kernel. > ok. The first debug section is done prior to holding the slab mutex and the second debug section is after holding mutex. I will have to think about the best way to restructure the code. I will send the re-worked patch soon, so we start refining it if need be. -- Shuah -- 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