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Date: Tue, 30 Apr 2002 09:58:42 -0700
From: Dave Hansen <haveblue@us.ibm.com>
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To: Arjan van de Ven <arjanv@redhat.com>
CC: g@redhat.com, Russell King <rmk@arm.linux.org.uk>,
        linux-kernel@vger.kernel.org
Subject: Re: devfs: BKL *not* taken while opening devices
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Arjan van de Ven wrote:
>>I like the idea.  But, while we're at it, does anyone have a good enough 
>>grasp of locking the the TTY layer that we can start peeling some of the 
>>BKL out of there?  Somebody was doing tests over a serial console here 
>>and the lockmeter data showed horrible BKL contention and hold times.
> 
> I really really doubt that fixing contention will make serial ports go
> faster... 

I know :)  It just takes extra explaining on my part whenever someone 
sees the lockmeter data.

 > it'll just move to another lock since I suspect we're
 > just waiting for hardware

Just about any other lock is preferrable to the BKL.  Should 
ext2_update_inode() be blocked because someone hit "Enter"?

-- 
Dave Hansen
haveblue@us.ibm.com

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