Re: dentry bloat.

[Andrew Morton]

Linus Torvalds <torvalds@xxxxxxxx> wrote:
>
> On Sat, 8 May 2004, Andrew Morton wrote:
>  > 
>  > I think we can simply take ->d_lock a bit earlier in __d_lookup.  That will
>  > serialise against d_move(), fixing the problem which you mention, and also
>  > makes d_movecount go away.
> 
>  If you do that, RCU basically loses most of it's meaning.
> 
>  You'll be taking a lock for - and dirtying in the cache - every single
>  dentry on the hash chain, which is pretty much guaranteed to be slower
>  than just taking the dcache_lock _once_, even if that one jumps across 
>  CPU's a lot.

Can take the lock after comparing the hash and the parent?

And if we recheck those after locking, d_movecount is unneeded?
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/