| Message ID | 1467721803-2138-2-git-send-email-deathsimple@vodafone.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jul 5, 2016 at 8:30 AM, Christian König <deathsimple@vodafone.de> wrote: > From: Christian König <christian.koenig@amd.com> > > Could be faster on the read path. > > Signed-off-by: Christian König <christian.koenig@amd.com> Just one style nit pick below. Beyond that, the series is: Reviewed-by: Alex Deucher <alexander.deucher@amd.com> > --- > drivers/gpu/drm/ttm/ttm_bo.c | 16 ++++++++++------ > drivers/gpu/drm/ttm/ttm_bo_util.c | 8 +++++--- > 2 files changed, 15 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c > index 66c50ad..7e30f3b 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo.c > +++ b/drivers/gpu/drm/ttm/ttm_bo.c > @@ -797,9 +797,11 @@ static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo, > struct fence *fence; > int ret; > > - spin_lock(&man->move_lock); > - fence = fence_get(man->move); > - spin_unlock(&man->move_lock); > + rcu_read_lock(); > + do > + fence = rcu_dereference(man->move); > + while (unlikely(fence && !fence_get_rcu(fence))); I generally like to see parens with do/while loops. > + rcu_read_unlock(); > > if (fence) { > reservation_object_add_shared_fence(bo->resv, fence); > @@ -1304,9 +1306,11 @@ static int ttm_bo_force_list_clean(struct ttm_bo_device *bdev, > } > spin_unlock(&glob->lru_lock); > > - spin_lock(&man->move_lock); > - fence = fence_get(man->move); > - spin_unlock(&man->move_lock); > + rcu_read_lock(); > + do > + fence = rcu_dereference(man->move); > + while (unlikely(fence && !fence_get_rcu(fence))); Same here. > + rcu_read_unlock(); > > if (fence) { > ret = fence_wait(fence, false); > diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c > index 4da0e78..fcd2431 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo_util.c > +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c > @@ -746,6 +746,7 @@ int ttm_bo_pipeline_move(struct ttm_buffer_object *bo, > ttm_bo_unref(&ghost_obj); > > } else if (from->flags & TTM_MEMTYPE_FLAG_FIXED) { > + struct fence *old; > > /** > * BO doesn't have a TTM we need to bind/unbind. Just remember > @@ -753,9 +754,10 @@ int ttm_bo_pipeline_move(struct ttm_buffer_object *bo, > */ > > spin_lock(&from->move_lock); > - if (!from->move || fence_is_later(fence, from->move)) { > - fence_put(from->move); > - from->move = fence_get(fence); > + old = rcu_dereference_protected(from->move, 1); > + if (!old || fence_is_later(fence, old)) { > + rcu_assign_pointer(from->move, fence_get(fence)); > + fence_put(old); > } > spin_unlock(&from->move_lock); > > -- > 2.5.0 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 66c50ad..7e30f3b 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -797,9 +797,11 @@ static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo, struct fence *fence; int ret; - spin_lock(&man->move_lock); - fence = fence_get(man->move); - spin_unlock(&man->move_lock); + rcu_read_lock(); + do + fence = rcu_dereference(man->move); + while (unlikely(fence && !fence_get_rcu(fence))); + rcu_read_unlock(); if (fence) { reservation_object_add_shared_fence(bo->resv, fence); @@ -1304,9 +1306,11 @@ static int ttm_bo_force_list_clean(struct ttm_bo_device *bdev, } spin_unlock(&glob->lru_lock); - spin_lock(&man->move_lock); - fence = fence_get(man->move); - spin_unlock(&man->move_lock); + rcu_read_lock(); + do + fence = rcu_dereference(man->move); + while (unlikely(fence && !fence_get_rcu(fence))); + rcu_read_unlock(); if (fence) { ret = fence_wait(fence, false); diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index 4da0e78..fcd2431 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -746,6 +746,7 @@ int ttm_bo_pipeline_move(struct ttm_buffer_object *bo, ttm_bo_unref(&ghost_obj); } else if (from->flags & TTM_MEMTYPE_FLAG_FIXED) { + struct fence *old; /** * BO doesn't have a TTM we need to bind/unbind. Just remember @@ -753,9 +754,10 @@ int ttm_bo_pipeline_move(struct ttm_buffer_object *bo, */ spin_lock(&from->move_lock); - if (!from->move || fence_is_later(fence, from->move)) { - fence_put(from->move); - from->move = fence_get(fence); + old = rcu_dereference_protected(from->move, 1); + if (!old || fence_is_later(fence, old)) { + rcu_assign_pointer(from->move, fence_get(fence)); + fence_put(old); } spin_unlock(&from->move_lock);