From: Qian Cai <cai@lca.pw>
To: Rafael Aquini <aquini@redhat.com>
Cc: Waiman Long <longman@redhat.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Johannes Weiner <hannes@cmpxchg.org>,
Michal Hocko <mhocko@kernel.org>, Roman Gushchin <guro@fb.com>,
Vlastimil Babka <vbabka@suse.cz>,
Konstantin Khlebnikov <khlebnikov@yandex-team.ru>,
Jann Horn <jannh@google.com>, Song Liu <songliubraving@fb.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH] mm/vmstat: Reduce zone lock hold time when reading /proc/pagetypeinfo
Date: Wed, 23 Oct 2019 11:51:44 -0400 [thread overview]
Message-ID: <1571845904.5937.89.camel@lca.pw> (raw)
In-Reply-To: <20191023150319.GD22601@optiplex-lnx>
On Wed, 2019-10-23 at 11:03 -0400, Rafael Aquini wrote:
> > > > this still isn't a bulletproof fix. Maybe just terminate the list
> > > > walk if freecount reaches 1024. Would anyone really care?
> > > >
> > > > Sigh. I wonder if anyone really uses this thing for anything
> > > > important. Can we just remove it all?
> > > >
> > >
> > > Removing it will be a breakage of kernel API.
> >
> > Who cares about breaking this part of the API that essentially nobody will use
> > this file?
> >
>
> Seems that _some_ are using it, aren't they? Otherwise we wouldn't be
> seeing complaints. Moving it out of /proc to /sys/kernel/debug looks
> like a reasonable compromise with those that care about the interface.
No, there are some known testing tools will blindly read this file just because
it exists which is not important to keep the file.
prev parent reply other threads:[~2019-10-23 15:51 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-22 16:21 [PATCH] mm/vmstat: Reduce zone lock hold time when reading /proc/pagetypeinfo Waiman Long
2019-10-22 16:57 ` Michal Hocko
2019-10-22 18:00 ` Waiman Long
2019-10-22 18:40 ` Waiman Long
2019-10-23 0:52 ` David Rientjes
2019-10-23 8:31 ` Mel Gorman
2019-10-23 9:04 ` Michal Hocko
2019-10-23 9:56 ` Mel Gorman
2019-10-23 10:27 ` [RFC PATCH 0/2] " Michal Hocko
2019-10-23 10:27 ` [RFC PATCH 1/2] mm, vmstat: hide /proc/pagetypeinfo from normal users Michal Hocko
2019-10-23 13:13 ` Mel Gorman
2019-10-23 13:27 ` Vlastimil Babka
2019-10-23 14:52 ` Waiman Long
2019-10-23 15:10 ` Rafael Aquini
2019-10-23 16:15 ` Vlastimil Babka
2019-10-24 19:01 ` David Rientjes
2019-10-23 10:27 ` [RFC PATCH 2/2] mm, vmstat: reduce zone->lock holding time by /proc/pagetypeinfo Michal Hocko
2019-10-23 13:15 ` Mel Gorman
2019-10-23 13:32 ` Vlastimil Babka
2019-10-23 13:37 ` Michal Hocko
2019-10-23 13:48 ` Vlastimil Babka
2019-10-23 14:31 ` Michal Hocko
2019-10-23 16:20 ` Vlastimil Babka
2019-10-23 13:46 ` Rafael Aquini
2019-10-23 14:56 ` Waiman Long
2019-10-23 15:21 ` Waiman Long
2019-10-23 16:10 ` Michal Hocko
2019-10-23 16:17 ` Waiman Long
2019-10-23 16:21 ` Waiman Long
2019-10-23 16:15 ` Vlastimil Babka
2019-10-23 16:41 ` Michal Hocko
2019-10-23 16:47 ` Waiman Long
2019-10-23 17:34 ` [PATCH 1/2] mm, vmstat: Release zone lock more frequently when reading /proc/pagetypeinfo Waiman Long
2019-10-23 18:01 ` Michal Hocko
2019-10-23 18:14 ` Waiman Long
2019-10-23 20:02 ` Michal Hocko
2019-10-23 17:34 ` [PATCH 2/2] mm, vmstat: List total free blocks for each order in /proc/pagetypeinfo Waiman Long
2019-10-23 18:02 ` Michal Hocko
2019-10-23 18:07 ` Waiman Long
2019-10-24 8:20 ` [RFC PATCH 0/2] mm/vmstat: Reduce zone lock hold time when reading /proc/pagetypeinfo Michal Hocko
2019-10-24 16:16 ` Waiman Long
2019-10-23 12:42 ` [PATCH] " Qian Cai
2019-10-23 13:25 ` Vlastimil Babka
2019-10-22 21:59 ` Andrew Morton
2019-10-23 6:15 ` Michal Hocko
2019-10-23 14:30 ` Waiman Long
2019-10-23 14:48 ` Qian Cai
2019-10-23 15:01 ` Waiman Long
2019-10-23 15:05 ` Qian Cai
2019-10-23 22:30 ` Andrew Morton
2019-10-24 5:33 ` Qian Cai
2019-10-24 7:42 ` Michal Hocko
2019-10-24 11:11 ` Qian Cai
2019-10-24 13:38 ` Michal Hocko
2019-10-24 14:55 ` Qian Cai
2019-10-24 3:33 ` Feng Tang
2019-10-24 4:34 ` Qian Cai
2019-10-24 5:34 ` Feng Tang
2019-10-24 10:51 ` Qian Cai
2019-10-25 1:38 ` Feng Tang
2019-10-23 15:03 ` Rafael Aquini
2019-10-23 15:51 ` Qian Cai [this message]
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