From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wm0-f66.google.com ([74.125.82.66]:45800 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754982AbeAJNVj (ORCPT ); Wed, 10 Jan 2018 08:21:39 -0500 Received: by mail-wm0-f66.google.com with SMTP id i186so10483713wmi.4 for ; Wed, 10 Jan 2018 05:21:38 -0800 (PST) Date: Wed, 10 Jan 2018 14:21:27 +0100 From: Daniel Vetter To: Christian =?iso-8859-1?Q?K=F6nig?= Cc: sumit.semwal@linaro.org, gustavo@padovan.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org Subject: Re: [Linaro-mm-sig] [PATCH] dma-buf: make returning the exclusive fence optional Message-ID: <20180110132127.GT13066@phenom.ffwll.local> References: <20180110125341.3618-1-christian.koenig@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20180110125341.3618-1-christian.koenig@amd.com> Sender: linux-media-owner@vger.kernel.org List-ID: On Wed, Jan 10, 2018 at 01:53:41PM +0100, Christian König wrote: > Change reservation_object_get_fences_rcu to make the exclusive fence > pointer optional. > > If not specified the exclusive fence is put into the fence array as > well. > > This is helpful for a couple of cases where we need all fences in a > single array. > > Signed-off-by: Christian König Seeing the use-case for this would be a lot more interesting ... -Daniel > --- > drivers/dma-buf/reservation.c | 31 ++++++++++++++++++++++--------- > 1 file changed, 22 insertions(+), 9 deletions(-) > > diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c > index b759a569b7b8..461afa9febd4 100644 > --- a/drivers/dma-buf/reservation.c > +++ b/drivers/dma-buf/reservation.c > @@ -374,8 +374,9 @@ EXPORT_SYMBOL(reservation_object_copy_fences); > * @pshared: the array of shared fence ptrs returned (array is krealloc'd to > * the required size, and must be freed by caller) > * > - * RETURNS > - * Zero or -errno > + * Retrieve all fences from the reservation object. If the pointer for the > + * exclusive fence is not specified the fence is put into the array of the > + * shared fences as well. Returns either zero or -ENOMEM. > */ > int reservation_object_get_fences_rcu(struct reservation_object *obj, > struct dma_fence **pfence_excl, > @@ -389,8 +390,8 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj, > > do { > struct reservation_object_list *fobj; > - unsigned seq; > - unsigned int i; > + unsigned int i, seq; > + size_t sz = 0; > > shared_count = i = 0; > > @@ -402,9 +403,14 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj, > goto unlock; > > fobj = rcu_dereference(obj->fence); > - if (fobj) { > + if (fobj) > + sz += sizeof(*shared) * fobj->shared_max; > + > + if (!pfence_excl && fence_excl) > + sz += sizeof(*shared); > + > + if (sz) { > struct dma_fence **nshared; > - size_t sz = sizeof(*shared) * fobj->shared_max; > > nshared = krealloc(shared, sz, > GFP_NOWAIT | __GFP_NOWARN); > @@ -420,13 +426,19 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj, > break; > } > shared = nshared; > - shared_count = fobj->shared_count; > - > + shared_count = fobj ? fobj->shared_count : 0; > for (i = 0; i < shared_count; ++i) { > shared[i] = rcu_dereference(fobj->shared[i]); > if (!dma_fence_get_rcu(shared[i])) > break; > } > + > + if (!pfence_excl && fence_excl) { > + shared[i] = fence_excl; > + fence_excl = NULL; > + ++i; > + ++shared_count; > + } > } > > if (i != shared_count || read_seqcount_retry(&obj->seq, seq)) { > @@ -448,7 +460,8 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj, > > *pshared_count = shared_count; > *pshared = shared; > - *pfence_excl = fence_excl; > + if (pfence_excl) > + *pfence_excl = fence_excl; > > return ret; > } > -- > 2.14.1 > > _______________________________________________ > Linaro-mm-sig mailing list > Linaro-mm-sig@lists.linaro.org > https://lists.linaro.org/mailman/listinfo/linaro-mm-sig -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch