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    SubjectRe: [PATCH] remove redundant NULL checks before kfree() in drivers/video/
    On Mon, 21 Mar 2005, Antonino A. Daplas wrote:
    > On Sunday 20 March 2005 06:59, Jesper Juhl wrote:
    > > Checking a pointer for NULL before calling kfree() on it is redundant,
    > > kfree() deals with NULL pointers just fine.
    > > This patch removes such checks from files in drivers/video/
    > >
    > > Since this is a fairly trivial change (and the same change made
    > > everywhere) I've just made a single patch for all the files and CC all
    > > authors/maintainers of those files I could find for comments. If spliting
    > > this into one patch pr file is prefered, then I can easily do that as
    > > well.
    > >
    >
    > [snip]
    >
    > > --- linux-2.6.11-mm4-orig/drivers/video/console/bitblit.c 2005-03-16
    > > 15:45:26.000000000 +0100 +++
    > > linux-2.6.11-mm4/drivers/video/console/bitblit.c 2005-03-19
    > > 22:27:39.000000000 +0100 @@ -199,8 +199,7 @@ static void bit_putcs(struct
    > > vc_data *vc
    > > count -= cnt;
    > > }
    > >
    > > - if (buf)
    > > - kfree(buf);
    > > + kfree(buf);
    > > }
    > >
    >
    > This is performance critical, so I would like the check to remain. A comment
    > may be added in this section.

    The first thing kfree() does is check for the NULL pointer. And since kfree()
    is used a lot, it's probably already in the cache.

    Gr{oetje,eeting}s,

    Geert

    --
    Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

    In personal conversations with technical people, I call myself a hacker. But
    when I'm talking to journalists I just say "programmer" or something like that.
    -- Linus Torvalds
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