| Message ID | 20121112141802.6326e589@endymion.delvare (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Nov 12, 2012 at 02:18:02PM +0100, Jean Delvare wrote: > DIV_ROUND_CLOSEST is faster if the compiler knows it will only be > dealing with unsigned dividends. This optimization rips 32 bytes of > binary code on x86_64. > > Signed-off-by: Jean Delvare <khali@linux-fr.org> > Cc: Guenter Roeck <linux@roeck-us.net> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > Cc: David Airlie <airlied@linux.ie> > --- > Already sent on: 2012-09-03. > > Daniel, I think we can safely assume ia_freq can't be negative? Queued for -next, thanks for the patch. Sorry that I've missed it on first submission. -Daniel
On Mon, 12 Nov 2012 15:02:26 +0100, Daniel Vetter wrote: > On Mon, Nov 12, 2012 at 02:18:02PM +0100, Jean Delvare wrote: > > DIV_ROUND_CLOSEST is faster if the compiler knows it will only be > > dealing with unsigned dividends. This optimization rips 32 bytes of > > binary code on x86_64. > > > > Signed-off-by: Jean Delvare <khali@linux-fr.org> > > Cc: Guenter Roeck <linux@roeck-us.net> > > Cc: Andrew Morton <akpm@linux-foundation.org> > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch> > > Cc: David Airlie <airlied@linux.ie> > > --- > > Already sent on: 2012-09-03. > > > > Daniel, I think we can safely assume ia_freq can't be negative? > > Queued for -next, thanks for the patch. Sorry that I've missed it on first > submission. No problem, thanks :)
--- linux-3.7-rc5.orig/drivers/gpu/drm/i915/intel_pm.c 2012-11-12 09:30:56.796836818 +0100 +++ linux-3.7-rc5/drivers/gpu/drm/i915/intel_pm.c 2012-11-12 10:49:38.241676096 +0100 @@ -2547,7 +2547,8 @@ static void gen6_update_ring_freq(struct { struct drm_i915_private *dev_priv = dev->dev_private; int min_freq = 15; - int gpu_freq, ia_freq, max_ia_freq; + int gpu_freq; + unsigned int ia_freq, max_ia_freq; int scaling_factor = 180; WARN_ON(!mutex_is_locked(&dev->struct_mutex));
DIV_ROUND_CLOSEST is faster if the compiler knows it will only be dealing with unsigned dividends. This optimization rips 32 bytes of binary code on x86_64. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> --- Already sent on: 2012-09-03. Daniel, I think we can safely assume ia_freq can't be negative? drivers/gpu/drm/i915/intel_pm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)