From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756689AbaDPVWH (ORCPT ); Wed, 16 Apr 2014 17:22:07 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:46444 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753049AbaDPVWE (ORCPT ); Wed, 16 Apr 2014 17:22:04 -0400 Date: Wed, 16 Apr 2014 14:22:02 -0700 From: Andrew Morton To: Sebastian Ott , Ingo Molnar , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/mempool: warn about __GFP_ZERO usage Message-Id: <20140416142202.f9d9cffa9bf1d9e5d5ed22c4@linux-foundation.org> In-Reply-To: <20140416141556.d50eef60d955d724ba1b02de@linux-foundation.org> References: <20140416141556.d50eef60d955d724ba1b02de@linux-foundation.org> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 16 Apr 2014 14:15:56 -0700 Andrew Morton wrote: > @@ -201,7 +201,9 @@ void * mempool_alloc(mempool_t *pool, gf > wait_queue_t wait; > gfp_t gfp_temp; > > - VM_BUG_ON(gfp_mask & __GFP_ZERO); > +#ifdef CONFIG_DEBUG_VM > + WARN_ON_ONCE(gfp_mask & __GFP_ZERO); /* Where's VM_WARN_ON_ONCE()? */ > +#endif bah, don't be lazy. From: Andrew Morton Subject: include/linux/mmdebug.h: add VM_WARN_ON() and VM_WARN_ON_ONCE() WARN_ON() and WARN_ON_ONCE(), dependent on CONFIG_DEBUG_VM Cc: Sebastian Ott Signed-off-by: Andrew Morton --- include/linux/mmdebug.h | 4 ++++ 1 file changed, 4 insertions(+) diff -puN include/linux/mmdebug.h~include-linux-mmdebugh-add-vm_warn_on-and-vm_warn_on_once include/linux/mmdebug.h --- a/include/linux/mmdebug.h~include-linux-mmdebugh-add-vm_warn_on-and-vm_warn_on_once +++ a/include/linux/mmdebug.h @@ -11,9 +11,13 @@ extern void dump_page_badflags(struct pa #define VM_BUG_ON(cond) BUG_ON(cond) #define VM_BUG_ON_PAGE(cond, page) \ do { if (unlikely(cond)) { dump_page(page, NULL); BUG(); } } while (0) +#define VM_WARN_ON(cond) WARN_ON(cond) +#define VM_WARN_ON_ONCE(cond) WARN_ON_ONCE(cond) #else #define VM_BUG_ON(cond) BUILD_BUG_ON_INVALID(cond) #define VM_BUG_ON_PAGE(cond, page) VM_BUG_ON(cond) +#define VM_WARN_ON(cond) BUILD_BUG_ON_INVALID(cond) +#define VM_WARN_ON_ONCE(cond) BUILD_BUG_ON_INVALID(cond) #endif #ifdef CONFIG_DEBUG_VIRTUAL _ From: Andrew Morton Subject: mm-mempool-warn-about-__gfp_zero-usage-fix use VM_WARN_ON_ONCE Cc: Sebastian Ott Signed-off-by: Andrew Morton --- mm/mempool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN mm/mempool.c~mm-mempool-warn-about-__gfp_zero-usage-fix mm/mempool.c --- a/mm/mempool.c~mm-mempool-warn-about-__gfp_zero-usage-fix +++ a/mm/mempool.c @@ -201,7 +201,7 @@ void * mempool_alloc(mempool_t *pool, gf wait_queue_t wait; gfp_t gfp_temp; - VM_BUG_ON(gfp_mask & __GFP_ZERO); + VM_WARN_ON_ONCE(gfp_mask & __GFP_ZERO); might_sleep_if(gfp_mask & __GFP_WAIT); gfp_mask |= __GFP_NOMEMALLOC; /* don't allocate emergency reserves */ _