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path: root/drivers/dma-buf/dma-fence.c
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2018-12-07dma-buf: make fence sequence numbers 64 bit v2Christian König
For a lot of use cases we need 64bit sequence numbers. Currently drivers overload the dma_fence structure to store the additional bits. Stop doing that and make the sequence number in the dma_fence always 64bit. For compatibility with hardware which can do only 32bit sequences the comparisons in __dma_fence_is_later only takes the lower 32bits as significant when the upper 32bits are all zero. v2: change the logic in __dma_fence_is_later Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Chunming Zhou <david1.zhou@amd.com> Link: https://patchwork.freedesktop.org/patch/266927/
2018-12-03dma-buf: add dma_fence_get_stubChristian König
Extract of useful code from the timeline work. This provides a function to return a stub or dummy fence which is always signaled. Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chunming Zhou <david1.zhou@amd.com> Link: https://patchwork.freedesktop.org/patch/265248/
2018-07-04dma-fence: Polish kernel-doc for dma-fence.cDaniel Vetter
- Intro section that links to how this is exposed to userspace. - Lots more hyperlinks. - Minor clarifications and style polish v2: Add misplaced hunk of kerneldoc from a different patch. Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Link: https://patchwork.freedesktop.org/patch/msgid/20180704092909.6599-6-daniel.vetter@ffwll.ch
2018-07-03dma-fence: Make ->wait callback optionalDaniel Vetter
Almost everyone uses dma_fence_default_wait. v2: Also remove the BUG_ON(!ops->wait) (Chris). Reviewed-by: Christian König <christian.koenig@amd.com> (v1) Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Link: https://patchwork.freedesktop.org/patch/msgid/20180503142603.28513-5-daniel.vetter@ffwll.ch
2018-07-02dma-fence: Allow wait_any_timeout for all fencesDaniel Vetter
When this was introduced in commit a519435a96597d8cd96123246fea4ae5a6c90b02 Author: Christian König <christian.koenig@amd.com> Date: Tue Oct 20 16:34:16 2015 +0200 dma-buf/fence: add fence_wait_any_timeout function v2 there was a restriction added that this only works if the dma-fence uses the dma_fence_default_wait hook. Which works for amdgpu, which is the only caller. Well, until you share some buffers with e.g. i915, then you get an -EINVAL. But there's really no reason for this, because all drivers must support callbacks. The special ->wait hook is only as an optimization; if the driver needs to create a worker thread for an active callback, then it can avoid to do that if it knows that there's a process context available already. So ->wait is just an optimization, just using the logic in dma_fence_default_wait() should work for all drivers. Let's remove this restriction. Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: Christian König <christian.koenig@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180503142603.28513-4-daniel.vetter@ffwll.ch
2018-07-02dma-fence: Make ->enable_signaling optionalDaniel Vetter
Many drivers have a trivial implementation for ->enable_signaling. Let's make it optional by assuming that signalling is already available when the callback isn't present. v2: Don't do the trick to set the ENABLE_SIGNAL_BIT unconditionally, it results in an expensive spinlock take for everyone. Instead just check if the callback is present. Suggested by Maarten. Also move misplaced kerneldoc hunk to the right patch. Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Christian König <christian.koenig@amd.com> (v1) Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Link: https://patchwork.freedesktop.org/patch/msgid/20180504141034.27727-1-daniel.vetter@ffwll.ch
2018-01-29dma-fence: add comment for WARN_ON in dma_fence_release()Oded Gabbay
In dma_fence_release() there is a WARN_ON which could be triggered by several cases of wrong dma-fence usage. This patch adds a comment to explain two use-cases to help driver developers that use dma-fence and trigger that WARN_ON to better understand the reasons for it. v2: change to a more generic, one-liner comment Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
2017-10-16tracing, dma-buf: Remove unused trace event dma_fence_annotate_wait_onSteven Rostedt (VMware)
Commit e941759c74 ("fence: dma-buf cross-device synchronization") added trace event fence_annotate_wait_on, but never used it. It was renamed to dma_fence_annotate_wait_on by commit f54d186700 ("dma-buf: Rename struct fence to dma_fence") but still not used. As defined trace events have data structures and functions created for them, it is a waste of memory if they are not used. Remove the unused trace event. Link: http://lkml.kernel.org/r/20171013100625.6c820059@gandalf.local.home Reviewed-by: Christian König <christian.koenig@amd.com> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-27Backmerge tag 'v4.13-rc2' into drm-nextDave Airlie
Linux 4.13-rc2 This is required for drm-misc fixing.
2017-07-26dma-fence: Don't BUG_ON when not absolutely neededDaniel Vetter
It makes debugging a massive pain. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Reviewed-by: Lucas Stach <l.stach@pengutronix.de> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170720125107.26693-1-daniel.vetter@ffwll.ch Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-07-17Merge branch 'drm-misc-next-fixes' into drm-misc-fixesSean Paul
Pick up 1ed134e6526b drm/vc4: Fix VBLANK handling in crtc->enable() path From drm-misc-next-fixes, it was applied after the last pull request was sent from that branch. We'll send it through drm-fixes instead.
2017-07-14dma-buf/fence: Avoid use of uninitialised timestampChris Wilson
[ 236.821534] WARNING: kmemcheck: Caught 64-bit read from uninitialized memory (ffff8802538683d0) [ 236.828642] 420000001e7f0000000000000000000000080000000000000000000000000000 [ 236.839543] i i i i u u u u i i i i i i i i u u u u u u u u u u u u u u u u [ 236.850420] ^ [ 236.854123] RIP: 0010:[<ffffffff81396f07>] [<ffffffff81396f07>] fence_signal+0x17/0xd0 [ 236.861313] RSP: 0018:ffff88024acd7ba0 EFLAGS: 00010282 [ 236.865027] RAX: ffffffff812f6a90 RBX: ffff8802527ca800 RCX: ffff880252cb30e0 [ 236.868801] RDX: ffff88024ac5d918 RSI: ffff880252f780e0 RDI: ffff880253868380 [ 236.872579] RBP: ffff88024acd7bc0 R08: ffff88024acd7be0 R09: 0000000000000000 [ 236.876407] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880253868380 [ 236.880185] R13: ffff8802538684d0 R14: ffff880253868380 R15: ffff88024cd48e00 [ 236.883983] FS: 00007f1646d1a740(0000) GS:ffff88025d000000(0000) knlGS:0000000000000000 [ 236.890959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 236.894702] CR2: ffff880251360318 CR3: 000000024ad21000 CR4: 00000000001406f0 [ 236.898481] [<ffffffff8130d1ad>] i915_gem_request_retire+0x1cd/0x230 [ 236.902439] [<ffffffff8130e2b3>] i915_gem_request_alloc+0xa3/0x2f0 [ 236.906435] [<ffffffff812fb1bd>] i915_gem_do_execbuffer.isra.41+0xb6d/0x18b0 [ 236.910434] [<ffffffff812fc265>] i915_gem_execbuffer2+0x95/0x1e0 [ 236.914390] [<ffffffff812ad625>] drm_ioctl+0x1e5/0x460 [ 236.918275] [<ffffffff8110d4cf>] do_vfs_ioctl+0x8f/0x5c0 [ 236.922168] [<ffffffff8110da3c>] SyS_ioctl+0x3c/0x70 [ 236.926090] [<ffffffff814b7a5f>] entry_SYSCALL_64_fastpath+0x17/0x93 [ 236.930045] [<ffffffffffffffff>] 0xffffffffffffffff We only set the timestamp before we mark the fence as signaled. It is done before to avoid observers having a window in which they may see the fence as complete but no timestamp. Having it does incur a potential for the timestamp to be written twice, and even for it to be corrupted if the u64 write is not atomic. Instead use a new bit to record the presence of the timestamp, and teach the readers to wait until it is set if the fence is complete. There still remains a race where the timestamp for the signaled fence may be shown before the fence is reported as signaled, but that's a pre-existing error. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: Daniel Vetter <daniel.vetter@intel.com> Reported-by: Rafael Antognolli <rafael.antognolli@intel.com> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170214124001.1930-1-chris@chris-wilson.co.uk
2017-04-27dma-buf: avoid scheduling on fence status query v2Andres Rodriguez
When a timeout of zero is specified, the caller is only interested in the fence status. In the current implementation, dma_fence_default_wait will always call schedule_timeout() at least once for an unsignaled fence. This adds a significant overhead to a fence status query. Avoid this overhead by returning early if a zero timeout is specified. v2: move early return after enable_signaling Signed-off-by: Andres Rodriguez <andresx7@gmail.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170426144620.3560-1-andresx7@gmail.com
2017-03-14Merge tag 'doc-4.11-images' of git://git.lwn.net/linux into drm-misc-nextDaniel Vetter
Pointer for Markus's image conversion work. We need this so we can merge all the pretty drm graphs for 4.12. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2017-03-07Merge tag 'drm-misc-next-2017-03-06' of ↵Dave Airlie
git://anongit.freedesktop.org/git/drm-misc into drm-next First slice of drm-misc-next for 4.12: Core/subsystem-wide: - link status core patch from Manasi, for signalling link train fail to userspace. I also had the i915 patch in here, but that had a small buglet in our CI, so reverted. - more debugfs_remove removal from Noralf, almost there now (Noralf said he'll try to follow up with the stragglers). - drm todo moved into kerneldoc, for better visibility (see Documentation/gpu/todo.rst), lots of starter tasks in there. - devm_ of helpers + use it in sti (from Ben Gaignard, acked by Rob Herring) - extended framebuffer fbdev support (for fbdev flipping), and vblank wait ioctl fbdev support (Maxime Ripard) - misc small things all over, as usual - add vblank callbacks to drm_crtc_funcs, plus make lots of good use of this to simplify drivers (Shawn Guo) - new atomic iterator macros to unconfuse old vs. new state Small drivers: - vc4 improvements from Eric - vc4 kerneldocs (Eric)! - tons of improvements for dw-mipi-dsi in rockchip from John Keeping and Chris Zhong. - MAINTAINERS entries for drivers managed in drm-misc. It's not yet official, still an experiment, but definitely not complete fail and better to avoid confusion. We kinda screwed that up with drm-misc a bit when we started committers last year. - qxl atomic conversion (Gabriel Krisman) - bunch of virtual driver polish (qxl, virgl, ...) - misc tiny patches all over This is the first time we've done the same merge-window blackout for drm-misc as we've done for drm-intel for ages, hence why we have a _lot_ of stuff queued already. But it's still only half of drm-intel (room to grow!), and the drivers in drm-misc experiment seems to work at least insofar as that you also get lots of driver updates here alredy. * tag 'drm-misc-next-2017-03-06' of git://anongit.freedesktop.org/git/drm-misc: (141 commits) drm/vc4: Fix OOPSes from trying to cache a partially constructed BO. drm/vc4: Fulfill user BO creation requests from the kernel BO cache. Revert "drm/i915: Implement Link Rate fallback on Link training failure" drm/fb-helper: implement ioctl FBIO_WAITFORVSYNC drm: Update drm_fbdev_cma_init documentation drm/rockchip/dsi: add dw-mipi power domain support drm/rockchip/dsi: fix insufficient bandwidth of some panel dt-bindings: add power domain node for dw-mipi-rockchip drm/rockchip/dsi: remove mode_valid function drm/rockchip/dsi: dw-mipi: correct the coding style drm/rockchip/dsi: dw-mipi: support RK3399 mipi dsi dt-bindings: add rk3399 support for dw-mipi-rockchip drm/rockchip: dw-mipi-dsi: add reset control drm/rockchip: dw-mipi-dsi: support non-burst modes drm/rockchip: dw-mipi-dsi: defer probe if panel is not loaded drm/rockchip: vop: test for P{H,V}SYNC drm/rockchip: dw-mipi-dsi: use positive check for N{H, V}SYNC drm/rockchip: dw-mipi-dsi: use specific poll helper drm/rockchip: dw-mipi-dsi: improve PLL configuration drm/rockchip: dw-mipi-dsi: properly configure PHY timing ...
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-16dma-buf/dma-fence: improve doc for dma_fence_add_callback()Gustavo Padovan
Document return values for this function. Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Link: http://patchwork.freedesktop.org/patch/msgid/20170215175725.6692-1-gustavo@padovan.org
2017-01-27dma/fence: Export enable-signaling tracepoint for emission by driversChris Wilson
Currently this tracepoint is solely used by dma_fence_enable_sw_signaling, however I have a need to manually perform the hw enabling of the signaling and would like to emit this tracepoint for completeness. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170124115758.31353-1-chris@chris-wilson.co.uk
2017-01-09dma-fence: Introduce drm_fence_set_error() helperChris Wilson
The dma_fence.error field (formerly known as dma_fence.status) is an optional field that may be set by drivers before calling dma_fence_signal(). The field can be used to indicate that the fence was completed in err rather than with success, and is visible to other consumers of the fence and to userspace via sync_file. This patch renames the field from status to error so that its meaning is hopefully more clear (and distinct from dma_fence_get_status() which is a composite between the error state and signal state) and adds a helper that validates the preconditions of when it is suitable to adjust the error field. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Link: http://patchwork.freedesktop.org/patch/msgid/20170104141222.6992-3-chris@chris-wilson.co.uk
2017-01-09dma-fence: Wrap querying the fence->statusChris Wilson
The fence->status is an optional field that is only valid once the fence has been signaled. (Driver may fill the fence->status with an error code prior to calling dma_fence_signal().) Given the restriction upon its validity, wrap querying of the fence->status into a helper dma_fence_get_status(). Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Link: http://patchwork.freedesktop.org/patch/msgid/20170104141222.6992-2-chris@chris-wilson.co.uk
2017-01-09dma-fence: Clear fence->status during dma_fence_init()Chris Wilson
As the fence->status is an optional field that may be set before dma_fence_signal() is called to convey that the fence completed with an error, we have to ensure that it is always set to zero on initialisation so that the typical use (i.e. unset) always flags a successful completion. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Link: http://patchwork.freedesktop.org/patch/msgid/20170104141222.6992-1-chris@chris-wilson.co.uk
2016-11-09dma-buf/fence: revert "don't wait when specified timeout is zero" (v2)Alex Deucher
Reverts commit 847b19a39e4c ("dma-buf/fence: don't wait when specified timeout is zero") When we don't call the wait function software signaling might never be activated. This can cause infinite polling loops with unreliable interrupt driven hardware. v2: rebase on drm-next Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Chunming Zhou <david1.zhou@amd.com> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> [sumits: reword commit msg for checkpatch warnings] Link: http://patchwork.freedesktop.org/patch/msgid/1478553376-18575-2-git-send-email-alexander.deucher@amd.com
2016-11-09dma-buf/fence: make timeout handling in fence_default_wait consistent (v2)Alex Deucher
Kernel functions taking a timeout usually return 1 on success even when they get a zero timeout. v2: agd: rebase on drm-next Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Chunming Zhou <david1.zhou@amd.com> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Link: http://patchwork.freedesktop.org/patch/msgid/1478553376-18575-1-git-send-email-alexander.deucher@amd.com
2016-11-09dma-buf: return index of the first signaled fence (v2)monk.liu
Return the index of the first signaled fence. This information is useful in some APIs like Vulkan. v2: rebase on drm-next (fence -> dma_fence) Signed-off-by: monk.liu <monk.liu@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> [sumits: fix warnings] Link: http://patchwork.freedesktop.org/patch/msgid/1478290570-30982-1-git-send-email-alexander.deucher@amd.com
2016-10-25dma-buf: Rename struct fence to dma_fenceChris Wilson
I plan to usurp the short name of struct fence for a core kernel struct, and so I need to rename the specialised fence/timeline for DMA operations to make room. A consensus was reached in https://lists.freedesktop.org/archives/dri-devel/2016-July/113083.html that making clear this fence applies to DMA operations was a good thing. Since then the patch has grown a bit as usage increases, so hopefully it remains a good thing! (v2...: rebase, rerun spatch) v3: Compile on msm, spotted a manual fixup that I broke. v4: Try again for msm, sorry Daniel coccinelle script: @@ @@ - struct fence + struct dma_fence @@ @@ - struct fence_ops + struct dma_fence_ops @@ @@ - struct fence_cb + struct dma_fence_cb @@ @@ - struct fence_array + struct dma_fence_array @@ @@ - enum fence_flag_bits + enum dma_fence_flag_bits @@ @@ ( - fence_init + dma_fence_init | - fence_release + dma_fence_release | - fence_free + dma_fence_free | - fence_get + dma_fence_get | - fence_get_rcu + dma_fence_get_rcu | - fence_put + dma_fence_put | - fence_signal + dma_fence_signal | - fence_signal_locked + dma_fence_signal_locked | - fence_default_wait + dma_fence_default_wait | - fence_add_callback + dma_fence_add_callback | - fence_remove_callback + dma_fence_remove_callback | - fence_enable_sw_signaling + dma_fence_enable_sw_signaling | - fence_is_signaled_locked + dma_fence_is_signaled_locked | - fence_is_signaled + dma_fence_is_signaled | - fence_is_later + dma_fence_is_later | - fence_later + dma_fence_later | - fence_wait_timeout + dma_fence_wait_timeout | - fence_wait_any_timeout + dma_fence_wait_any_timeout | - fence_wait + dma_fence_wait | - fence_context_alloc + dma_fence_context_alloc | - fence_array_create + dma_fence_array_create | - to_fence_array + to_dma_fence_array | - fence_is_array + dma_fence_is_array | - trace_fence_emit + trace_dma_fence_emit | - FENCE_TRACE + DMA_FENCE_TRACE | - FENCE_WARN + DMA_FENCE_WARN | - FENCE_ERR + DMA_FENCE_ERR ) ( ... ) Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20161025120045.28839-1-chris@chris-wilson.co.uk