Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1287990

Re: [PATCH] mm: memcontrol: only manage socket pressure for CONFIG_INET

From Johannes Weiner <hannes@cmpxchg.org>
Newsgroups linux.kernel
Subject Re: [PATCH] mm: memcontrol: only manage socket pressure for CONFIG_INET
Date 2015-12-10 00:10 +0100
Message-ID <qDW20-6ob-53@gated-at.bofh.it> (permalink)
References <qDswV-48l-7@gated-at.bofh.it> <qDPWx-2lU-9@gated-at.bofh.it> <qDPWx-2lU-7@gated-at.bofh.it> <qDS82-3Fq-9@gated-at.bofh.it> <qDVph-5UZ-25@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Wed, Dec 09, 2015 at 02:28:36PM -0800, Andrew Morton wrote:
> On Wed, 9 Dec 2015 13:58:58 -0500 Johannes Weiner <hannes@cmpxchg.org> wrote:
> 
> > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > > index 6faea81e66d7..73cd572167bb 100644
> > > --- a/mm/memcontrol.c
> > > +++ b/mm/memcontrol.c
> > > @@ -4220,13 +4220,13 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css)
> > >  	if (ret)
> > >  		return ret;
> > >  
> > > +#ifdef CONFIG_INET
> > >  #ifdef CONFIG_MEMCG_LEGACY_KMEM
> > >  	ret = tcp_init_cgroup(memcg);
> > >  	if (ret)
> > >  		return ret;
> > >  #endif
> > 
> > The calls to tcp_init_cgroup() appear earlier in the series than "mm:
> > memcontrol: hook up vmpressure to socket pressure". However, they get
> > moved around a few times so fixing it earlier means respinning the
> > series. Andrew, it's up to you whether we take the bisectability hit
> > for !CONFIG_INET && CONFIG_MEMCG (how common is this?) or whether you
> > want me to resend the series.
> 
> hm, drat, I was suspecting dependency issues here, but a test build
> said it was OK.
> 
> Actually, I was expecting this patch series to depend on the linux-next
> cgroup2 changes, but that doesn't appear to be the case.  *should* this
> series be staged after the cgroup2 code?

Code-wise they are independent. My stuff is finishing up the new memcg
control knobs, the cgroup2 stuff is changing how and when those knobs
are exposed from within the cgroup core. I'm not relying on any recent
changes in the cgroup core AFAICS, so the order shouldn't matter here.

> Regarding this particular series: yes, I think we can live with a
> bisection hole for !CONFIG_INET && CONFIG_MEMCG users.  But I'm not
> sure why we're discussing bisection issues, because Arnd's build
> failure occurs with everything applied?

Arnd's patches apply to the top of the stack, but they address issues
introduced early in the series and the problematic code gets touched a
lot in subsequent patches. E.g. the first build breakage is in ("net:
tcp_memcontrol: simplify linkage between socket and page counter")
when the tcp_init_cgroup() and tcp_destroy_cgroup() function calls get
moved around and lose the CONFIG_INET protection.

This will leave states in between broken for this configuration, which
is why I brought up bisection. Or did you mean something else?

> > Sorry about the trouble. I don't have a git tree on kernel.org because
> > we don't really use git in -mm, but the downside is that we don't get
> > the benefits of the automatic build testing for all kinds of configs.
> > I'll try to set up a git tree to expose series to full build coverage
> > before they hit -mm and -next.
> 
> This sort of thing happens quite rarely.

True, this is a particularly tedious one. The only reason I brought it
up is because I use git to prepare patches anyway, and pushing patches
into a branch reachable by Fengguang's rig before I send emails might
have caught this stuff without spamming so many inboxes ;)

Anyway, if we can live with the bisection caveat then Arnd's fixes on
top of the kmem series look good to me. Depending on what Vladimir
thinks we might want to replace the CONFIG_SLOB fix with something
else later on, but that shouldn't be a problem, either.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH 00/14] mm: memcontrol: account socket memory in unified hierarchy v4-RESEND Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 01/14] mm: memcontrol: export root_mem_cgroup Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 06/14] net: tcp_memcontrol: simplify the per-memcg limit access Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 09/14] mm: memcontrol: generalize the socket accounting jump label Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 05/14] net: tcp_memcontrol: remove dead per-memcg count of allocated sockets Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 02/14] net: tcp_memcontrol: properly detect ancestor socket pressure Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 08/14] net: tcp_memcontrol: simplify linkage between socket and page counter Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 04/14] net: tcp_memcontrol: protect all tcp_memcontrol calls by jump-label Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 11/14] mm: memcontrol: move socket code for unified hierarchy accounting Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  [PATCH 13/14] mm: memcontrol: hook up vmpressure to socket pressure Johannes Weiner <hannes@cmpxchg.org> - 2015-12-08 16:40 +0100
  Re: [PATCH 00/14] mm: memcontrol: account socket memory in unified  hierarchy v4-RESEND David Miller <davem@davemloft.net> - 2015-12-08 17:30 +0100
  [PATCH] mm: memcontrol: only manage socket pressure for CONFIG_INET Arnd Bergmann <arnd@arndb.de> - 2015-12-09 17:40 +0100
    Re: [PATCH] mm: memcontrol: only manage socket pressure for  CONFIG_INET Johannes Weiner <hannes@cmpxchg.org> - 2015-12-09 20:00 +0100
      Re: [PATCH] mm: memcontrol: only manage socket pressure for  CONFIG_INET Andrew Morton <akpm@linux-foundation.org> - 2015-12-09 23:30 +0100
        Re: [PATCH] mm: memcontrol: only manage socket pressure for  CONFIG_INET Johannes Weiner <hannes@cmpxchg.org> - 2015-12-10 00:10 +0100
          Re: [PATCH] mm: memcontrol: only manage socket pressure for  CONFIG_INET Andrew Morton <akpm@linux-foundation.org> - 2015-12-10 00:20 +0100
  [PATCH] mm: memcontrol: MEMCG no longer works with SLOB Arnd Bergmann <arnd@arndb.de> - 2015-12-09 17:40 +0100
    Re: [PATCH] mm: memcontrol: MEMCG no longer works with SLOB Johannes Weiner <hannes@cmpxchg.org> - 2015-12-09 21:10 +0100
      Re: [PATCH] mm: memcontrol: MEMCG no longer works with SLOB Arnd Bergmann <arnd@arndb.de> - 2015-12-09 22:10 +0100
      Re: [PATCH] mm: memcontrol: MEMCG no longer works with SLOB Vladimir Davydov <vdavydov@virtuozzo.com> - 2015-12-10 12:30 +0100
  Re: [PATCH 00/14] mm: memcontrol: account socket memory in unified hierarchy v4-RESEND Arnd Bergmann <arnd@arndb.de> - 2015-12-09 17:40 +0100
    Re: [PATCH 00/14] mm: memcontrol: account socket memory in unified  hierarchy v4-RESEND Johannes Weiner <hannes@cmpxchg.org> - 2015-12-09 19:20 +0100

csiph-web