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Subject: Re: [PATCH 1/3] printk: Release console_sem after logbuf_lock
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>,
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Date: Fri, 10 Jun 2011 13:28:31 +0200
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On Thu, 2011-06-09 at 16:57 -0700, Hugh Dickins wrote:
> 
> All console-related activity curently happens under spin_lock_irqsave(&console_lock). 
> This causes interrutps to be blocked for 1-2 milliseconds with vgacon, and for
> hundreds of milliseconds with fbdevs.  This results in network overruns, audio
> dropouts, dropped characters on serial ports and other such nice things.

Hmm, with these proposed patches we're actually back to that. I wonder
if fbdev is still that crappy..