linux/drivers/dma-buf, branch v4.19

dma-buf: Move BUG_ON from _add_shared_fence to _add_shared_inplace

2018-07-16T14:50:37Z

Fixes the BUG_ON spuriously triggering under the following circumstances: * reservation_object_reserve_shared is called with shared_count == shared_max - 1, so obj->staged is freed in preparation of an in-place update. * reservation_object_add_shared_fence is called with the first fence, after which shared_count == shared_max. * reservation_object_add_shared_fence is called with a follow-up fence from the same context. In the second reservation_object_add_shared_fence call, the BUG_ON triggers. However, nothing bad would happen in reservation_object_add_shared_inplace, since both fences are from the same context, so they only occupy a single slot. Prevent this by moving the BUG_ON to where an overflow would actually happen (e.g. if a buggy caller didn't call reservation_object_reserve_shared before). v2: * Fix description of breaking scenario (Christian König) * Add bugzilla reference Cc: stable@vger.kernel.org Bugzilla: https://bugs.freedesktop.org/106418 Reviewed-by: Chris Wilson # v1 Reviewed-by: Christian König # v1 Signed-off-by: Michel Dänzer Signed-off-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/msgid/20180704151405.10357-1-michel@daenzer.net

Merge tag 'drm-misc-next-2018-07-04' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

2018-07-06T00:01:56Z

drm-misc-next for 4.19: UAPI Changes: v3d: add fourcc modicfier for fourcc for the Broadcom UIF format (Eric Anholt) Cross-subsystem Changes: console/fbcon: Add support for deferred console takeover (Hans de Goede) Core Changes: dma-fence clean up, improvements and docs (Daniel Vetter) add mask function for crtc, plane, encoder and connector DRM objects(Ville Syrjälä) Driver Changes: pl111: add Nomadik LCDC variant (Linus Walleij) Signed-off-by: Dave Airlie Link: https://patchwork.freedesktop.org/patch/msgid/20180704234641.GA3981@juma

dma-fence: Polish kernel-doc for dma-fence.c

2018-07-04T10:18:37Z

- 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 Signed-off-by: Daniel Vetter Cc: Sumit Semwal Cc: Gustavo Padovan 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

dma-fence: Make ->wait callback optional

2018-07-03T11:12:57Z

Almost everyone uses dma_fence_default_wait. v2: Also remove the BUG_ON(!ops->wait) (Chris). Reviewed-by: Christian König (v1) Signed-off-by: Daniel Vetter Cc: Chris Wilson Cc: Sumit Semwal Cc: Gustavo Padovan 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

locking: Implement an algorithm choice for Wound-Wait mutexes

2018-07-03T07:44:36Z

The current Wound-Wait mutex algorithm is actually not Wound-Wait but Wait-Die. Implement also Wound-Wait as a per-ww-class choice. Wound-Wait is, contrary to Wait-Die a preemptive algorithm and is known to generate fewer backoffs. Testing reveals that this is true if the number of simultaneous contending transactions is small. As the number of simultaneous contending threads increases, Wait-Wound becomes inferior to Wait-Die in terms of elapsed time. Possibly due to the larger number of held locks of sleeping transactions. Update documentation and callers. Timings using git://people.freedesktop.org/~thomash/ww_mutex_test tag patch-18-06-15 Each thread runs 100000 batches of lock / unlock 800 ww mutexes randomly chosen out of 100000. Four core Intel x86_64: Algorithm #threads Rollbacks time Wound-Wait 4 ~100 ~17s. Wait-Die 4 ~150000 ~19s. Wound-Wait 16 ~360000 ~109s. Wait-Die 16 ~450000 ~82s. Cc: Ingo Molnar Cc: Jonathan Corbet Cc: Gustavo Padovan Cc: Maarten Lankhorst Cc: Sean Paul Cc: David Airlie Cc: Davidlohr Bueso Cc: "Paul E. McKenney" Cc: Josh Triplett Cc: Thomas Gleixner Cc: Kate Stewart Cc: Philippe Ombredanne Cc: Greg Kroah-Hartman Cc: linux-doc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Co-authored-by: Peter Zijlstra Signed-off-by: Thomas Hellstrom Acked-by: Peter Zijlstra (Intel) Acked-by: Ingo Molnar

dma-fence: Allow wait_any_timeout for all fences

2018-07-02T08:20:53Z

When this was introduced in commit a519435a96597d8cd96123246fea4ae5a6c90b02 Author: Christian König 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 Signed-off-by: Daniel Vetter Cc: Sumit Semwal Cc: Gustavo Padovan Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: Christian König Cc: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20180503142603.28513-4-daniel.vetter@ffwll.ch

dma-fence: Make ->enable_signaling optional

2018-07-02T08:16:33Z

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 Reviewed-by: Christian König (v1) Reviewed-by: Maarten Lankhorst Signed-off-by: Daniel Vetter Cc: Sumit Semwal Cc: Gustavo Padovan 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

dma-buf: remove kmap_atomic interface

2018-06-20T13:59:34Z

Neither used nor correctly implemented anywhere. Just completely remove the interface. Signed-off-by: Christian König Reviewed-by: Daniel Vetter Acked-by: Sumit Semwal Link: https://patchwork.freedesktop.org/patch/226645/

dma_buf: remove device parameter from attach callback v2

2018-06-20T13:59:34Z

The device parameter is completely unused because it is available in the attachment structure as well. v2: fix kerneldoc as well Signed-off-by: Christian König Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/226643/

dma-buf: make map_atomic and map function pointers optional

2018-06-01T06:59:35Z

So drivers don't need dummy functions just returning NULL. Cc: Daniel Vetter Signed-off-by: Gerd Hoffmann Reviewed-by: Daniel Vetter Reviewed-by: Oleksandr Andrushchenko Link: http://patchwork.freedesktop.org/patch/msgid/20180529135918.19729-1-kraxel@redhat.com