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Date: Sun, 14 Feb 2016 22:01:55 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jeff Layton <jlayton@poochiereds.net>,
	Eryu Guan <guaneryu@gmail.com>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Jan Kara <jack@suse.com>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [BUG] inotify_add_watch/inotify_rm_watch loops trigger oom
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On Sun, Feb 14, 2016 at 06:33:25PM -0800, Linus Torvalds wrote:
> On Sun, Feb 14, 2016 at 5:02 PM, Paul E. McKenney
> <paulmck@linux.vnet.ibm.com> wrote:
> >
> > One thought would be to add an "emergency mode" to SRCU similar to that
> > already in RCU.  Something to the effect that if the current list of
> > callbacks is going to take more than a second to drain at the configured
> > per-jiffy rate, just process them without waiting.
> >
> > Would that help in this case, or am I missing something about the
> > reproducer?
> 
> Let's see if we can avoid srcu callbacks entirely as per Jeff, that
> would be the best option.

Agreed, no point in adding complication without use cases.

							Thanx, Paul