Re: [Devel] Re: [PATCH 2.6.19-rc3] VFS: per-sb dentry lru list

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wednesday November 1, [email protected] wrote:
> <<<< AFAICS, doing so you introduced a leak of anonymous dentries.
> 
> d_alloc_anon() calls d_alloc() with parent == NULL, i.e. dentries have no parent
> and are not linked to the sb->s_root...

Yep, thanks.

> BTW, looking at it, I found that s_anon field on super block is not
> used any more. 

I don't know what you mean by that.  It is still used...

> we can add BUG_ON(!hlist_empty(&sb->s_anon)) in generic_shutdown_super to avoid such issues like this.
> 
> maybe we can fix it adding something like:
> while (!list_empty(&sb->s_anon)))
>     prune_dcache(MAX_INT, &sb->s_anon);

It seems that anon dentries can now have children (I think someone
explained that too me - shrink_dcache_for_umount certainly suggests
it).
Also, in this context we cannot be sure that all dentries can be
freed.  This is being called a remount time remember, and some stuff
might still be in use.

We probably need to move the s_anon list to a temporary list and
repeatedly:
  move the top entry back to s_anon and call shrink_dcache_parent
 on it.

Needs more thought.
	
NeilBrown
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux