lkml.org 
[lkml]   [2003]   [Jul]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] Fastwalk: reduce cacheline bouncing of d_count ()
On Tue, Jul 08, 2003 at 05:53:34PM +0100, Alan Cox wrote:
> On Maw, 2003-07-08 at 17:44, Herbert Poetzl wrote:
> > > Its no big problem to me since I can just back it out of -ac
> >
> > just curious, because I use this patch since early 2.4.20,
> > are there any reasons to 'back it out of -ac' for you?
> >
> > anyway I totally agree that the NFS issue pointed out by
> > Trond should be addressed ...
>
> Its high risk, its got bugs as Trond already showed and it only
> helps performance on giant SMP boxes. Its all risk and no
> reward. Quota updates get you working 32bit uid quota and
> the interactivity stuff helps all even tho its got some
> risk.

every change (if it's not a bugfix, and even those) bear
a risk, what I like about the fastwalk patch is not the
performance gain on giant SMP boxes, because I do not have
any (unfortunately ;) but the code change from ...

if (path_init(pathname, LOOKUP_PARENT, &nd))
error = path_walk(pathname, &nd);

to
error = path_lookup(pathname, LOOKUP_PARENT, &nd);


and

dentry = cached_lookup(nd->dentry, &this, 0);
if (!dentry) {
dentry = real_lookup(nd->dentry, &this, 0);
err = PTR_ERR(dentry);
if (IS_ERR(dentry))
break;
}

to
err = do_lookup(nd, &this, &next, &pinned, 0);


which (at least for me) is more read-/understandable ...

anyway, thanks for you answer,
Herbert

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:46    [W:0.069 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site