lkml.org 
[lkml]   [2008]   [Sep]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] VFS: make file->f_pos access atomic on 32bit arch
Hi,



----- Messaggio originale -----
> Da: Nick Piggin <nickpiggin@yahoo.com.au>
> A: Michael Trimarchi <trimarchimichael@yahoo.it>
> Cc: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>; akpm@linux-foundation.org; linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org
> Inviato: Martedì 16 settembre 2008, 14:54:21
> Oggetto: Re: [PATCH] VFS: make file->f_pos access atomic on 32bit arch
>
> On Tuesday 16 September 2008 21:11, Michael Trimarchi wrote:
> > Hi,
> >
> > > + if (offset != file_pos_read(file))
> > > + file_pos_write(file, offset);
> > > retval = offset;
> > > }
> >
> > Is not more efficient here a compare xchg operation?
>
> The compiler should do it if it was.
> --
> 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/

i was thinking about introducing a file_pos_update() not implemented using
file_pos_read()/file_pos_write() and taking the seq_lock or
disabling preemption only one time

__________________________________________________
Do You Yahoo!?
Poco spazio e tanto spam? Yahoo! Mail ti protegge dallo spam e ti da tanto spazio gratuito per i tuoi file e i messaggi
http://mail.yahoo.it
--
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: 2008-09-16 16:01    [W:0.055 / U:0.052 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site