On Wed, Nov 18, 2009 at 3:17 PM, Américo Wang <xiyou.wangcong@xxxxxxxxx> wrote:
>
> On Wed, Nov 18, 2009 at 1:54 PM, Liu Aleaxander <aleaxander@xxxxxxxxx> wrote:
> > From: Liu Aleaxander <Aleaxander@xxxxxxxxx>
> > Date: Wed, 18 Nov 2009 10:59:09 +0800
> > Subject: [PATCH] vfs: does call expand_files when needed
> >
> > I don't think we should call expand_files every time we open a
> > file for a new unused fd, so does the expand when necessary.
> >
> > Signed-off-by: Liu Aleaxander <Aleaxander@xxxxxxxxx>
> > ---
> > fs/file.c | 27 ++++++++++++++-------------
> > 1 files changed, 14 insertions(+), 13 deletions(-)
> >
> > diff --git a/fs/file.c b/fs/file.c
> > index 87e1290..3f3d0fc 100644
> > --- a/fs/file.c
> > +++ b/fs/file.c
> > @@ -452,22 +452,22 @@ repeat:
> > if (fd < files->next_fd)
> > fd = files->next_fd;
> >
> > - if (fd < fdt->max_fds)
> > + if (likely(fd < fdt->max_fds)) {
> > fd = find_next_zero_bit(fdt->open_fds->fds_bits,
> > fdt->max_fds, fd);
> > -
> > - error = expand_files(files, fd);
> > - if (error < 0)
> > - goto out;
> > -
> > - /*
> > - * If we needed to expand the fs array we
> > - * might have blocked - try again.
> > - */
> > - if (error)
> > - goto repeat;
> > -
> > + } else {
> > + error = expand_files(files, fd);
>
>
> In expand_files(), it has the check for
> ' < fdt->max_fds', so this change is not necessary.
Yeah, indeed. But why we should go into an another function to do a
_double_ check especially we mostly don't need to do that?
>
> > + if (error < 0)
> > + goto out;
> > +
> > + /*
> > + * If we needed to expand the fs array we
> > + * might have blocked - try again.
> > + */
> > + if (error)
> > + goto repeat;
> > + }
> > +
> > if (start <= files->next_fd)
> > files->next_fd = fd + 1;
> >
> > --
> > 1.6.2.5
> >
> > --
> > regards
> > Liu Aleaxander
> > --
> > 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/
> >
--
regards
Liu Aleaxander
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
