| Message ID | 1493977209-10970-1-git-send-email-joonas.lahtinen@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, May 05, 2017 at 12:40:09PM +0300, Joonas Lahtinen wrote: > Due to the complex dependencies between workqueues and RCU, which > are not easily detected by lockdep, do not synchronize RCU during > shrinking. RCU sync gains us very little benefit in real life > scenarios where the amount of memory used by object backing > storage is dominant over the metadata under RCU. > > Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> > Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > Cc: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> > Cc: J. R. Okajima <hooanon05g@gmail.com> > Cc: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> -Chris
diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c b/drivers/gpu/drm/i915/i915_gem_shrinker.c index 0e7352d..e1868ed 100644 --- a/drivers/gpu/drm/i915/i915_gem_shrinker.c +++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c @@ -59,9 +59,6 @@ static void shrinker_unlock(struct drm_i915_private *dev_priv, bool unlock) return; mutex_unlock(&dev_priv->drm.struct_mutex); - - /* expedite the RCU grace period to free some request slabs */ - synchronize_rcu_expedited(); } static bool any_vma_pinned(struct drm_i915_gem_object *obj)
Due to the complex dependencies between workqueues and RCU, which are not easily detected by lockdep, do not synchronize RCU during shrinking. RCU sync gains us very little benefit in real life scenarios where the amount of memory used by object backing storage is dominant over the metadata under RCU. Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: J. R. Okajima <hooanon05g@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> --- drivers/gpu/drm/i915/i915_gem_shrinker.c | 3 --- 1 file changed, 3 deletions(-)