From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [RFC] fs, proc: Introduce the /proc/<pid>/map_files/ directory v2
Date: Fri, 26 Aug 2011 16:27:21 +0200
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To: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>, Andrew Morton <akpm@linux-foundation.org>, Pavel Emelyanov <xemul@parallels.com>, linux-kernel@vger.kernel.org, James Bottomley <jbottomley@parallels.com>, containers@lists.osdl.org, Andi Kleen <andi@firstfloor.org>, Nathan Lynch <ntl@pobox.com>, LINUXFS-ML <linux-fsdevel@vger.kernel.org>, Zan Lynx <zlynx@acm.org>, Daniel Lezcano <dlezcano@fr.ibm.com>, Vasiliy Kulikov <segoon@openwall.com>
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Hello,

On Fri, Aug 26, 2011 at 05:23:34PM +0300, Kirill A. Shutemov wrote:
> On Fri, Aug 26, 2011 at 04:06:20PM +0200, Tejun Heo wrote:
> > > +struct map_files_info {
> > > +	struct file	*file;
> > > +	unsigned char	name[16+16+2]; /* max: %016lx-%016lx\0 */
> > > +	unsigned long	len;
> > > +};
> > 
> > That's slightly above 50 bytes.
> 
> We can use 4 * sizeof(unsigned long) + 2 for name to save a bit on 32 bit
> architectures.

Ooh, I wasn't trying to say it was too big.  I was trying to say it
would be okay to have that on stack.  :)

> BTW, show_map_vma() uses "%08lx-%08lx" to print ->start, ->end. I think
> it's good idea to use this here as well to be consistent with
> /proc/$PID/{s,}maps

I'm not too sure about this one.  First of all, I think %08lx is more
of an accident than intention (just forgot to update it while
transitioning to 64bit) and when ls'd the output can be a bit messy
without leading 0's, but again my opinion here isn't very strong.

Thanks.

-- 
tejun