On Sun, Feb 13, 2011 at 09:38:04PM +0100, Marcin Slusarz wrote: > Combination of locking and interchannel synchronization changes > uncovered poor behaviour of nouveau_fence_wait, which on HZ=100 > configuration could waste up to 10 ms per call. > Depending on application, it lead to 10-30% FPS regression. > To fix it, shorten thread sleep time to 0.1 ms and ensure > spinning happens for at least one *full* tick. > > Signed-off-by: Marcin Slusarz <[email protected]> > --- > drivers/gpu/drm/nouveau/nouveau_fence.c | 10 ++++++++-- > 1 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c > b/drivers/gpu/drm/nouveau/nouveau_fence.c > index 221b846..75ba5e2 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_fence.c > +++ b/drivers/gpu/drm/nouveau/nouveau_fence.c > @@ -27,6 +27,9 @@ > #include "drmP.h" > #include "drm.h" > > +#include <linux/ktime.h> > +#include <linux/hrtimer.h> > + > #include "nouveau_drv.h" > #include "nouveau_ramht.h" > #include "nouveau_dma.h" > @@ -230,9 +233,12 @@ int > __nouveau_fence_wait(void *sync_obj, void *sync_arg, bool lazy, bool intr) > { > unsigned long timeout = jiffies + (3 * DRM_HZ); > - unsigned long sleep_time = jiffies + 1; > + unsigned long sleep_time = jiffies + 2; > + ktime_t t; > int ret = 0; > > + t = ktime_set(0, NSEC_PER_MSEC / 10); > + > while (1) { > if (__nouveau_fence_signalled(sync_obj, sync_arg)) > break; > @@ -245,7 +251,7 @@ __nouveau_fence_wait(void *sync_obj, void *sync_arg, bool > lazy, bool intr) > __set_current_state(intr ? TASK_INTERRUPTIBLE > : TASK_UNINTERRUPTIBLE); > if (lazy && time_after_eq(jiffies, sleep_time)) > - schedule_timeout(1); > + schedule_hrtimeout(&t, HRTIMER_MODE_REL); > > if (intr && signal_pending(current)) { > ret = -ERESTARTSYS; > -- > 1.7.4.rc3 >
http://www.youtube.com/watch?v=arCITMfxvEc#t=2m11s Your favourite machine ;), Marcin _______________________________________________ Nouveau mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/nouveau
