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Date: Fri, 7 May 2004 16:32:35 -0700
From: Andrew Morton <akpm@osdl.org>
To: Jack Steiner <steiner@sgi.com>
Cc: paulmck@us.ibm.com, linux-kernel@vger.kernel.org
Subject: Re: RCU scaling on large systems
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Jack Steiner <steiner@sgi.com> wrote:
>
> The calls to RCU are coming from here:
> 
> 	[11]kdb> bt
> 	Stack traceback for pid 3553
> 	0xe00002b007230000     3553     3139  1   11   R  0xe00002b0072304f0 *ls
> 	0xa0000001000feee0 call_rcu
> 	0xa0000001001a3b20 d_free+0x80
> 	0xa0000001001a3ec0 dput+0x340
> 	0xa00000010016bcd0 __fput+0x210
> 	0xa00000010016baa0 fput+0x40
> 	0xa000000100168760 filp_close+0xc0
> 	0xa000000100168960 sys_close+0x180
> 	0xa000000100011be0 ia64_ret_from_syscall
> 
> I see this same backtrace from numerous processes.

eh?  Why is dput freeing the dentry?  It should just be leaving it in cache.

What filesystem is being used?  procfs?