Tue, 2017-06-20, 23:05 +0300-യ്ക്ക, Dan Carpenter എഴുതിയിരിക്കുന്നു:
> On Tue, Jun 20, 2017 at 06:50:13PM +0200, Dhananjay Balan wrote:
> > The locking and unlocking code used by copy routines is common, so
> > moved it to a macro.
> >
> > Signed-off-by: Dhananjay Balan <mail@xxxxxxxxx>
> > ---
> > drivers/staging/sm750fb/sm750.c | 81 ++++++++++++++++-------------
> > ------------
> > 1 file changed, 31 insertions(+), 50 deletions(-)
> >
> > diff --git a/drivers/staging/sm750fb/sm750.c
> > b/drivers/staging/sm750fb/sm750.c
> > index 386d4adcd91d..d8ab83aea46d 100644
> > --- a/drivers/staging/sm750fb/sm750.c
> > +++ b/drivers/staging/sm750fb/sm750.c
> > @@ -156,12 +156,25 @@ static int lynxfb_ops_cursor(struct fb_info
> > *info, struct fb_cursor *fbcursor)
> > return 0;
> > }
> >
> > +/*
> > + * If not using spin_lock, system will die if user frequently
> > loads and
> > + * immediately unloads driver (dual)
> > + */
> > +#define dual_safe_call(func, ...)
> > \
> > + do {
> > \
> > + if (sm750_dev->fb_count > 1)
> > \
> > + spin_lock(&sm750_dev->slock);
> > \
> > + func(__VA_ARGS__);
> > \
> > + if (sm750_dev->fb_count > 1)
> > \
> > + spin_unlock(&sm750_dev->slock);
> > \
> > + } while (0)
> > +
>
> I feel like this is the wrong approach. You could just make a small
> lock function and a small unlock function. Except that if statement
> seems kind of bogus. What happens if ->fb_count is 0 when we lock
> and
> 1 when we unlock? Why not lock unconditionally? It is not likely to
> be
> contested if there are no other users.
I've to admit that I don't have much info, but is fb_count supposed to
change during this execution?
>
> > static void lynxfb_ops_fillrect(struct fb_info *info,
> > const struct fb_fillrect *region)
> > {
> > struct lynxfb_par *par;
> > struct sm750_dev *sm750_dev;
> > - unsigned int base, pitch, Bpp, rop;
> > + unsigned int base, pitch, bit_pp, rop;
>
> This part has nothing to do with locking... *frowny face*
Sorry about that, I'll split this into separate commit.
Thanks,
Dhananjay Balan.
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