From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maarten Lankhorst Subject: Re: [PATCH] drm/i915: Android sync points for i915 Date: Fri, 01 Aug 2014 08:23:49 +0200 Message-ID: <53DB3275.6010102@canonical.com> References: <1406833088-25801-1-git-send-email-jbarnes@virtuousgeek.org> <1406833088-25801-2-git-send-email-jbarnes@virtuousgeek.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mblankhorst.nl (mblankhorst.nl [141.105.120.124]) by gabe.freedesktop.org (Postfix) with ESMTP id 3C7236E70B for ; Thu, 31 Jul 2014 23:34:22 -0700 (PDT) In-Reply-To: <1406833088-25801-2-git-send-email-jbarnes@virtuousgeek.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Jesse Barnes , intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org Hey, On 31-07-14 20:58, Jesse Barnes wrote: > Expose an ioctl to create Android fences based on the Android sync point > infrastructure (which in turn is based on DMA-buf fences). Just a > sketch at this point, no testing has been done. > > There are a couple of goals here: > 1) allow applications and libraries to create fences without an > associated buffer > 2) re-use a common API so userspace doesn't have to impedance mismatch > between different driver implementations too much > 3) allow applications and libraries to use explicit synchronization if > they choose by exposing fences directly > Do you really need to use android timelines here? I think you should be able to use fence directly, and export android userspace fences anyway, you could easily wrap them. ~Maarten Untested uncompiled patch for that below, looking from the documentation I may have caused a memory leak by taking a reference on the sync_pt.. --- diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index ba0d69e..201b088 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -179,7 +179,7 @@ static void fence_check_cb_func(struct fence *f, struct fence_cb *cb) } /* TODO: implement a create which takes more that one sync_pt */ -struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt) +struct sync_fence *sync_fence_create_dma(const char *name, struct fence *pt) { struct sync_fence *fence; @@ -190,16 +190,21 @@ struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt) fence->num_fences = 1; atomic_set(&fence->status, 1); - fence_get(&pt->base); - fence->cbs[0].sync_pt = &pt->base; + fence->cbs[0].sync_pt = fence_get(pt); fence->cbs[0].fence = fence; - if (fence_add_callback(&pt->base, &fence->cbs[0].cb, fence_check_cb_func)) + if (fence_add_callback(pt, &fence->cbs[0].cb, fence_check_cb_func)) atomic_dec(&fence->status); sync_fence_debug_add(fence); return fence; } +EXPORT_SYMBOL(sync_fence_create_dma); + +struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt) +{ + return sync_fence_create_dma(name, &pt->base); +} EXPORT_SYMBOL(sync_fence_create); struct sync_fence *sync_fence_fdget(int fd) diff --git a/drivers/staging/android/sync.h b/drivers/staging/android/sync.h index bcdd119..6d1682a 100644 --- a/drivers/staging/android/sync.h +++ b/drivers/staging/android/sync.h @@ -242,8 +242,9 @@ void sync_pt_free(struct sync_pt *pt); * @pt: sync_pt to add to the fence * * Creates a fence containg @pt. Once this is called, the fence takes - * ownership of @pt. + * a reference on @pt. */ +struct sync_fence *sync_fence_create_dma(const char *name, struct fence *pt); struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt); /*