From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f48.google.com (mail-wg0-f48.google.com [74.125.82.48]) by kanga.kvack.org (Postfix) with ESMTP id C0BA06B0032 for ; Tue, 9 Jun 2015 06:21:14 -0400 (EDT) Received: by wgme6 with SMTP id e6so9357808wgm.2 for ; Tue, 09 Jun 2015 03:21:14 -0700 (PDT) Received: from szxga01-in.huawei.com (szxga01-in.huawei.com. [58.251.152.64]) by mx.google.com with ESMTPS id fa9si2365948wid.33.2015.06.09.03.21.11 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 09 Jun 2015 03:21:13 -0700 (PDT) Message-ID: <5576BB3C.50100@huawei.com> Date: Tue, 9 Jun 2015 18:09:00 +0800 From: Xishi Qiu MIME-Version: 1.0 Subject: Re: [RFC PATCH 08/12] mm: use mirrorable to switch allocate mirrored memory References: <55704A7E.5030507@huawei.com> <55704C79.5060608@huawei.com> <55769058.3030406@jp.fujitsu.com> In-Reply-To: <55769058.3030406@jp.fujitsu.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Kamezawa Hiroyuki Cc: Andrew Morton , nao.horiguchi@gmail.com, Yinghai Lu , "H. Peter Anvin" , Thomas Gleixner , mingo@elte.hu, Xiexiuqi , Hanjun Guo , "Luck, Tony" , Linux MM , LKML On 2015/6/9 15:06, Kamezawa Hiroyuki wrote: > On 2015/06/04 22:02, Xishi Qiu wrote: >> Add a new interface in path /proc/sys/vm/mirrorable. When set to 1, it means >> we should allocate mirrored memory for both user and kernel processes. >> >> Signed-off-by: Xishi Qiu > > I can't see why do we need this switch. If this is set, all GFP_HIGHUSER will use > mirrored memory ? > > Or will you add special MMAP/madvise flag to use mirrored memory ? > Hi Kame, Yes, MMAP/madvise -> add VM_MIRROR -> add GFP_MIRROR -> use MIGRATE_MIRROR list to alloc mirrored pages So user can use mirrored memory. What do you think? Thanks, Xishi Qiu > Thanks, > -Kame > >> --- >> include/linux/mmzone.h | 1 + >> kernel/sysctl.c | 9 +++++++++ >> mm/page_alloc.c | 1 + >> 3 files changed, 11 insertions(+) >> >> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h >> index f82e3ae..20888dd 100644 >> --- a/include/linux/mmzone.h >> +++ b/include/linux/mmzone.h >> @@ -85,6 +85,7 @@ struct mirror_info { >> }; >> >> extern struct mirror_info mirror_info; >> +extern int sysctl_mirrorable; >> # define is_migrate_mirror(migratetype) unlikely((migratetype) == MIGRATE_MIRROR) >> #else >> # define is_migrate_mirror(migratetype) false >> diff --git a/kernel/sysctl.c b/kernel/sysctl.c >> index 2082b1a..dc2625e 100644 >> --- a/kernel/sysctl.c >> +++ b/kernel/sysctl.c >> @@ -1514,6 +1514,15 @@ static struct ctl_table vm_table[] = { >> .extra2 = &one, >> }, >> #endif >> +#ifdef CONFIG_MEMORY_MIRROR >> + { >> + .procname = "mirrorable", >> + .data = &sysctl_mirrorable, >> + .maxlen = sizeof(sysctl_mirrorable), >> + .mode = 0644, >> + .proc_handler = proc_dointvec_minmax, >> + }, >> +#endif >> { >> .procname = "user_reserve_kbytes", >> .data = &sysctl_user_reserve_kbytes, >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index 249a8f6..63b90ca 100644 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -212,6 +212,7 @@ int user_min_free_kbytes = -1; >> >> #ifdef CONFIG_MEMORY_MIRROR >> struct mirror_info mirror_info; >> +int sysctl_mirrorable = 0; >> #endif >> >> static unsigned long __meminitdata nr_kernel_pages; >> > > > > . > -- 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