On Thu, Sep 07, 2017 at 09:13:32AM +0200, Christian König wrote: > Ping? David can you take a look? > > Alex is on vacation and that is a rather important bug fix. Works better when you cc Gustavo/Maarten/Sumits/Chris I think, for anything dma-buf review needing. -Daniel > > Thanks, > Christian. > > Am 04.09.2017 um 21:02 schrieb Christian König: > > From: Christian König <christian.koenig@xxxxxxx> > > > > Stop requiring that the src reservation object is locked for this operation. > > > > Signed-off-by: Christian König <christian.koenig@xxxxxxx> > > --- > > drivers/dma-buf/reservation.c | 56 ++++++++++++++++++++++++++++++++----------- > > 1 file changed, 42 insertions(+), 14 deletions(-) > > > > diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c > > index dec3a81..b44d9d7 100644 > > --- a/drivers/dma-buf/reservation.c > > +++ b/drivers/dma-buf/reservation.c > > @@ -266,8 +266,7 @@ EXPORT_SYMBOL(reservation_object_add_excl_fence); > > * @dst: the destination reservation object > > * @src: the source reservation object > > * > > -* Copy all fences from src to dst. Both src->lock as well as dst-lock must be > > -* held. > > +* Copy all fences from src to dst. dst-lock must be held. > > */ > > int reservation_object_copy_fences(struct reservation_object *dst, > > struct reservation_object *src) > > @@ -277,33 +276,62 @@ int reservation_object_copy_fences(struct reservation_object *dst, > > size_t size; > > unsigned i; > > - src_list = reservation_object_get_list(src); > > + rcu_read_lock(); > > + src_list = rcu_dereference(src->fence); > > +retry: > > if (src_list) { > > - size = offsetof(typeof(*src_list), > > - shared[src_list->shared_count]); > > + unsigned shared_count = src_list->shared_count; > > + > > + size = offsetof(typeof(*src_list), shared[shared_count]); > > + rcu_read_unlock(); > > + > > dst_list = kmalloc(size, GFP_KERNEL); > > if (!dst_list) > > return -ENOMEM; > > - dst_list->shared_count = src_list->shared_count; > > - dst_list->shared_max = src_list->shared_count; > > - for (i = 0; i < src_list->shared_count; ++i) > > - dst_list->shared[i] = > > - dma_fence_get(src_list->shared[i]); > > + rcu_read_lock(); > > + src_list = rcu_dereference(src->fence); > > + if (!src_list || src_list->shared_count > shared_count) { > > + kfree(dst_list); > > + goto retry; > > + } > > + > > + dst_list->shared_count = 0; > > + dst_list->shared_max = shared_count; > > + for (i = 0; i < src_list->shared_count; ++i) { > > + struct dma_fence *fence; > > + > > + fence = rcu_dereference(src_list->shared[i]); > > + if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, > > + &fence->flags)) > > + continue; > > + > > + if (!dma_fence_get_rcu(fence)) { > > + kfree(dst_list); > > + src_list = rcu_dereference(src->fence); > > + goto retry; > > + } > > + > > + if (dma_fence_is_signaled(fence)) { > > + dma_fence_put(fence); > > + continue; > > + } > > + > > + dst_list->shared[dst_list->shared_count++] = fence; > > + } > > } else { > > dst_list = NULL; > > } > > + new = dma_fence_get_rcu_safe(&src->fence_excl); > > + rcu_read_unlock(); > > + > > kfree(dst->staged); > > dst->staged = NULL; > > src_list = reservation_object_get_list(dst); > > - > > old = reservation_object_get_excl(dst); > > - new = reservation_object_get_excl(src); > > - > > - dma_fence_get(new); > > preempt_disable(); > > write_seqcount_begin(&dst->seq); > > > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel