From: Michal Hocko <mhocko@kernel.org>
To: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>,
Heiko Carstens <heiko.carstens@de.ibm.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
Greg KH <gregkh@linuxfoundation.org>,
"K. Y. Srinivasan" <kys@microsoft.com>,
David Rientjes <rientjes@google.com>,
Daniel Kiper <daniel.kiper@oracle.com>,
linux-api@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
linux-s390@vger.kernel.org, xen-devel@lists.xenproject.org,
linux-acpi@vger.kernel.org, qiuxishi@huawei.com,
toshi.kani@hpe.com, xieyisheng1@huawei.com, slaoub@gmail.com,
iamjoonsoo.kim@lge.com, vbabka@suse.cz,
Zhang Zhen <zhenzhang.zhang@huawei.com>,
Yasuaki Ishimatsu <yasu.isimatu@gmail.com>,
Tang Chen <tangchen@cn.fujitsu.com>
Subject: Re: WTH is going on with memory hotplug sysf interface (was: Re: [RFC PATCH] mm, hotplug: get rid of auto_online_blocks)
Date: Mon, 13 Mar 2017 10:21:45 +0100 [thread overview]
Message-ID: <20170313092145.GG31518@dhcp22.suse.cz> (raw)
In-Reply-To: <20170310190037.fifahjd47joim6zy@arbab-laptop>
On Fri 10-03-17 13:00:37, Reza Arbab wrote:
> On Fri, Mar 10, 2017 at 04:53:33PM +0100, Michal Hocko wrote:
> >OK, so while I was playing with this setup some more I probably got why
> >this is done this way. All new memblocks are added to the zone Normal
> >where they are accounted as spanned but not present.
>
> It's not always zone Normal. See zone_for_memory(). This leads to a
> workaround for having to do online_movable in descending block order.
> Instead of this:
>
> 1. probe block 34, probe block 33, probe block 32, ...
> 2. online_movable 34, online_movable 33, online_movable 32, ...
>
> you can online_movable the first block before adding the rest:
I do I enforce that behavior when the probe happens automagically?
> 1. probe block 32, online_movable 32
> 2. probe block 33, probe block 34, ...
> - zone_for_memory() will cause these to start Movable
> 3. online 33, online 34, ...
> - they're already in Movable, so online_movable is equivalentr
>
> I agree with your general sentiment that this stuff is very nonintuitive.
My criterion for nonintuitive is probably different because I would call
this _completely_unusable_. Sorry for being so loud about this but the
more I look into this area the more WTF code I see. This has seen close
to zero review and seems to be building up more single usecase code on
top of previous. We need to change this, seriously!
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2017-03-13 9:22 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-27 9:28 [RFC PATCH] mm, hotplug: get rid of auto_online_blocks Michal Hocko
2017-02-27 10:02 ` Vitaly Kuznetsov
2017-02-27 10:21 ` Michal Hocko
2017-02-27 10:49 ` Vitaly Kuznetsov
2017-02-27 12:56 ` Michal Hocko
2017-02-27 13:17 ` Vitaly Kuznetsov
2017-02-27 11:25 ` Heiko Carstens
2017-02-27 11:50 ` Vitaly Kuznetsov
2017-02-27 15:43 ` Michal Hocko
2017-02-28 10:21 ` Heiko Carstens
2017-03-02 13:53 ` Igor Mammedov
2017-03-02 14:28 ` Michal Hocko
2017-03-02 17:03 ` Igor Mammedov
2017-03-03 8:27 ` Michal Hocko
2017-03-03 17:34 ` Igor Mammedov
2017-03-06 14:54 ` Michal Hocko
2017-03-07 12:40 ` Igor Mammedov
2017-03-09 12:54 ` Michal Hocko
2017-03-10 13:58 ` WTH is going on with memory hotplug sysf interface (was: Re: [RFC PATCH] mm, hotplug: get rid of auto_online_blocks) Michal Hocko
2017-03-10 15:53 ` Michal Hocko
2017-03-10 19:00 ` Reza Arbab
2017-03-13 9:21 ` Michal Hocko [this message]
2017-03-13 14:58 ` Reza Arbab
2017-03-14 19:35 ` Andrea Arcangeli
2017-03-15 7:57 ` Michal Hocko
2017-03-13 15:11 ` Michal Hocko
2017-03-13 23:16 ` Andi Kleen
2017-03-10 17:39 ` WTH is going on with memory hotplug sysf interface Yasuaki Ishimatsu
2017-03-13 9:19 ` Michal Hocko
2017-03-14 16:05 ` YASUAKI ISHIMATSU
2017-03-14 16:20 ` Michal Hocko
2017-03-13 10:31 ` WTH is going on with memory hotplug sysf interface (was: Re: [RFC PATCH] mm, hotplug: get rid of auto_online_blocks) Igor Mammedov
2017-03-13 10:43 ` Michal Hocko
2017-03-13 13:57 ` Igor Mammedov
2017-03-13 14:36 ` Michal Hocko
2017-03-13 10:55 ` [RFC PATCH] mm, hotplug: get rid of auto_online_blocks Igor Mammedov
2017-03-13 12:28 ` Michal Hocko
2017-03-13 12:54 ` Vitaly Kuznetsov
2017-03-13 13:19 ` Michal Hocko
2017-03-13 13:42 ` Vitaly Kuznetsov
2017-03-13 14:32 ` Michal Hocko
2017-03-13 15:10 ` Vitaly Kuznetsov
2017-03-14 13:20 ` Igor Mammedov
2017-03-15 7:53 ` Michal Hocko
2017-03-10 22:00 ` Daniel Kiper
2017-02-27 17:28 ` Reza Arbab
2017-02-27 17:34 ` Michal Hocko
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