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Date: Wed, 19 Sep 2018 08:07:06 +0200
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vaibhav Nagarnaik <vnagarnaik@google.com>,
        Jason Behmer <jbehmer@google.com>, stable@vger.kernel.org
Subject: Re: [GIT PULL] ring-buffer: Allow for rescheduling when removing
 pages
Message-ID: <20180919060706.GA17950@kroah.com>
References: <20180918191413.4426aef4@gandalf.local.home>
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On Tue, Sep 18, 2018 at 07:14:13PM -0400, Steven Rostedt wrote:
> 
> Linus (aka Greg),
> 
> Vaibhav Nagarnaik found that modifying the ring buffer size could cause
> a huge latency in the system because it does a while loop to free pages
> without releasing the CPU (on non preempt kernels). In a case where there
> are hundreds of thousands of pages to free it could actually cause a system
> stall. A properly place cond_resched() solves this issue.
> 
> 
> Please pull the latest trace-v4.19-rc4 tree, which can be found at:
> 
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
> trace-v4.19-rc4

Ick, line wrapping makes it hard to cut/paste :(

Anyway, now pulled and pushed out.

greg k-h