From: Oleg Nesterov <oleg@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Mel Gorman <mgorman@suse.de>, Rik van Riel <riel@redhat.com>,
Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
Ingo Molnar <mingo@kernel.org>,
Andrea Arcangeli <aarcange@redhat.com>,
Johannes Weiner <hannes@cmpxchg.org>,
Thomas Gleixner <tglx@linutronix.de>,
Steven Rostedt <rostedt@goodmis.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] rcu: Create rcu_sync infrastructure
Date: Fri, 4 Oct 2013 17:13:23 +0200 [thread overview]
Message-ID: <20131004151323.GA16440@redhat.com> (raw)
In-Reply-To: <20131004144319.GM3081@twins.programming.kicks-ass.net>
On 10/04, Peter Zijlstra wrote:
>
> On Fri, Oct 04, 2013 at 03:31:35PM +0200, Oleg Nesterov wrote:
> > > I'm really starting to think we shouldn't do this in rcu_sync at all.
> >
> > I do not really understand why you insist that rcu_sync() should not
> > try to help to the users which need the exclusive mode.
>
> But what other users; you yourself said that percpu-rwsem isn't one for
> long if ever.
Not sure I understand...
percpu-rwsem will use exclusive mode, with or without the possible
improvements we can copy from cpuhp. sb_writers can probably use it
too (along with other helpers from percpu-rwsem we do not have yet).
If you mean that the "raw" rcu_sync infrastructure will never have
more users, will I am not sure, it looks "natural". But I can not
know for sure.
OK, I am not going to argue too much, let me send other patches
you seem to agree with. I am also going to send this one for the
record/review (without __complete_locked), please ack-or-nack it
explicitly.
I am not trying saying this feature is "must have", of course it
is not. The only problem, I am a bit puzzled why you dislike it
that much.
Oleg.
next prev parent reply other threads:[~2013-10-04 15:20 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-02 14:56 [PATCH 0/3] Optimize the cpu hotplug locking Peter Zijlstra
2013-10-02 14:56 ` [PATCH 1/3] hotplug: Optimize {get,put}_online_cpus() Peter Zijlstra
2013-10-03 14:01 ` Peter Zijlstra
2013-10-03 16:27 ` Paul E. McKenney
2013-10-03 16:26 ` Paul E. McKenney
2013-10-02 14:56 ` [PATCH 2/3] rcu: Create rcu_sync infrastructure Peter Zijlstra
2013-10-02 15:49 ` Oleg Nesterov
2013-10-03 16:42 ` Paul E. McKenney
2013-10-08 8:18 ` Peter Zijlstra
2013-10-03 16:41 ` Paul E. McKenney
2013-10-03 17:00 ` Oleg Nesterov
2013-10-03 17:15 ` Paul E. McKenney
2013-10-03 18:40 ` Peter Zijlstra
2013-10-03 18:45 ` Paul E. McKenney
2013-10-03 18:47 ` Oleg Nesterov
2013-10-03 19:21 ` Paul E. McKenney
2013-10-03 19:32 ` Oleg Nesterov
2013-10-03 19:33 ` Oleg Nesterov
2013-10-03 19:50 ` Paul E. McKenney
2013-10-03 20:00 ` Oleg Nesterov
2013-10-03 21:10 ` Oleg Nesterov
2013-10-03 22:00 ` Paul E. McKenney
2013-10-04 11:29 ` Oleg Nesterov
2013-10-04 16:22 ` Paul E. McKenney
2013-10-04 7:18 ` Peter Zijlstra
2013-10-04 11:15 ` Oleg Nesterov
2013-10-04 11:36 ` Peter Zijlstra
2013-10-04 11:50 ` Oleg Nesterov
2013-10-04 11:44 ` Peter Zijlstra
2013-10-04 12:13 ` Oleg Nesterov
2013-10-04 12:38 ` Peter Zijlstra
2013-10-04 13:31 ` Oleg Nesterov
2013-10-04 14:43 ` Peter Zijlstra
2013-10-04 15:13 ` Oleg Nesterov [this message]
2013-10-04 16:25 ` Peter Zijlstra
2013-10-04 19:06 ` Oleg Nesterov
2013-10-04 19:41 ` Peter Zijlstra
2013-10-05 17:31 ` Oleg Nesterov
2013-10-04 7:00 ` Peter Zijlstra
2013-10-03 20:14 ` Paolo Bonzini
2013-10-04 7:01 ` Peter Zijlstra
2013-10-02 14:56 ` [PATCH 3/3] hotplug: Optimize cpu_hotplug_{begin,done}() using rcu_sync Peter Zijlstra
2013-10-03 16:48 ` Paul E. McKenney
2013-10-03 18:41 ` Peter Zijlstra
2013-10-03 18:46 ` Paul E. McKenney
2013-10-03 19:05 ` Oleg Nesterov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20131004151323.GA16440@redhat.com \
--to=oleg@redhat.com \
--cc=aarcange@redhat.com \
--cc=hannes@cmpxchg.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mgorman@suse.de \
--cc=mingo@kernel.org \
--cc=paulmck@linux.vnet.ibm.com \
--cc=peterz@infradead.org \
--cc=riel@redhat.com \
--cc=rostedt@goodmis.org \
--cc=srikar@linux.vnet.ibm.com \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).