From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754207AbbJPNRb (ORCPT ); Fri, 16 Oct 2015 09:17:31 -0400 Received: from mail-wi0-f176.google.com ([209.85.212.176]:35203 "EHLO mail-wi0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751870AbbJPNR3 (ORCPT ); Fri, 16 Oct 2015 09:17:29 -0400 Date: Fri, 16 Oct 2015 16:17:26 +0300 From: "Kirill A. Shutemov" To: Vladimir Davydov Cc: Andrew Morton , Johannes Weiner , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] memcg: simplify and inline __mem_cgroup_from_kmem Message-ID: <20151016131726.GA602@node.shutemov.name> References: <9be67d8528d316ce90d78980bce9ed76b00ffd22.1443996201.git.vdavydov@virtuozzo.com> <517ab1701f4b53be8bfd6691a1499598efb358e7.1443996201.git.vdavydov@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <517ab1701f4b53be8bfd6691a1499598efb358e7.1443996201.git.vdavydov@virtuozzo.com> User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 05, 2015 at 01:21:43AM +0300, Vladimir Davydov wrote: > Before the previous patch, __mem_cgroup_from_kmem had to handle two > types of kmem - slab pages and pages allocated with alloc_kmem_pages - > differently, because slab pages did not store information about owner > memcg in the page struct. Now we can unify it. Since after it, this > function becomes tiny we can fold it into mem_cgroup_from_kmem. > > Signed-off-by: Vladimir Davydov > --- > include/linux/memcontrol.h | 7 ++++--- > mm/memcontrol.c | 18 ------------------ > 2 files changed, 4 insertions(+), 21 deletions(-) > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index 8a9b7a798f14..0e2e039609d1 100644 > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -769,8 +769,6 @@ static inline int memcg_cache_id(struct mem_cgroup *memcg) > struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep); > void __memcg_kmem_put_cache(struct kmem_cache *cachep); > > -struct mem_cgroup *__mem_cgroup_from_kmem(void *ptr); > - > static inline bool __memcg_kmem_bypass(gfp_t gfp) > { > if (!memcg_kmem_enabled()) > @@ -832,9 +830,12 @@ static __always_inline void memcg_kmem_put_cache(struct kmem_cache *cachep) > > static __always_inline struct mem_cgroup *mem_cgroup_from_kmem(void *ptr) > { > + struct page *page; > + > if (!memcg_kmem_enabled()) > return NULL; > - return __mem_cgroup_from_kmem(ptr); > + page = virt_to_head_page(ptr); > + return page->mem_cgroup; > } virt_to_head_page() is defined in but you don't include it, and the commit breaks build for me (on v4.3-rc5-mmotm-2015-10-15-15-20). CC arch/x86/kernel/asm-offsets.s In file included from /home/kas/linux/mm/include/linux/swap.h:8:0, from /home/kas/linux/mm/include/linux/suspend.h:4, from /home/kas/linux/mm/arch/x86/kernel/asm-offsets.c:12: /home/kas/linux/mm/include/linux/memcontrol.h: In function ‘mem_cgroup_from_kmem’: /home/kas/linux/mm/include/linux/memcontrol.h:841:9: error: implicit declaration of function ‘virt_to_head_page’ [-Werror=implicit-function-declaration] page = virt_to_head_page(ptr); ^ /home/kas/linux/mm/include/linux/memcontrol.h:841:7: warning: assignment makes pointer from integer without a cast [-Wint-conversion] page = virt_to_head_page(ptr); ^ In file included from /home/kas/linux/mm/include/linux/suspend.h:8:0, from /home/kas/linux/mm/arch/x86/kernel/asm-offsets.c:12: /home/kas/linux/mm/include/linux/mm.h: At top level: /home/kas/linux/mm/include/linux/mm.h:452:28: error: conflicting types for ‘virt_to_head_page’ static inline struct page *virt_to_head_page(const void *x) ^ In file included from /home/kas/linux/mm/include/linux/swap.h:8:0, from /home/kas/linux/mm/include/linux/suspend.h:4, from /home/kas/linux/mm/arch/x86/kernel/asm-offsets.c:12: /home/kas/linux/mm/include/linux/memcontrol.h:841:9: note: previous implicit declaration of ‘virt_to_head_page’ was here page = virt_to_head_page(ptr); ^ cc1: some warnings being treated as errors The patch below fixes it for me (and for allmodconfig on x86-64), but I'm not sure if it have any side effects on other configurations. diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 47677acb4516..e8e52e502c20 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -26,6 +26,7 @@ #include #include #include +#include #include #include -- Kirill A. Shutemov