Commit Graph

30 Commits

Author SHA1 Message Date
Chris Wilson
f5b07b04e5 dma-buf: Discard old fence_excl on retrying get_fences_rcu for realloc
If we have to drop the seqcount & rcu lock to perform a krealloc, we
have to restart the loop. In doing so, be careful not to lose track of
the already acquired exclusive fence.

Fixes: fedf54132d ("dma-buf: Restart reservation_object_get_fences_rcu() after writes")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: stable@vger.kernel.org #v4.10
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190604125323.21396-1-chris@chris-wilson.co.uk
2019-06-05 07:38:37 +01:00
Lucas Stach
547c7138bc dma-buf: add some lockdep asserts to the reservation object implementation
This adds lockdep asserts to the reservation functions which state in their
documentation that obj->lock must be held. Allows builds with PROVE_LOCKING
enabled to check that the locking requirements are met.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180111165302.25556-1-l.stach@pengutronix.de
2019-02-27 23:51:43 +01:00
Chris Wilson
a590d0fdba dma-buf: Update reservation shared_count after adding the new fence
We need to serialise the addition of a new fence into the shared list
such that the fence is visible before we claim it is there. Otherwise a
concurrent reader of the shared fence list will see an uninitialised
fence slot before it is set.

  <4> [109.613162] general protection fault: 0000 [#1] PREEMPT SMP PTI
  <4> [109.613177] CPU: 1 PID: 1357 Comm: gem_busy Tainted: G     U            4.19.0-rc8-CI-CI_DRM_5035+ #1
  <4> [109.613189] Hardware name: Dell Inc. XPS 8300  /0Y2MRG, BIOS A06 10/17/2011
  <4> [109.613252] RIP: 0010:i915_gem_busy_ioctl+0x146/0x380 [i915]
  <4> [109.613261] Code: 0b 43 04 49 83 c6 08 4d 39 e6 89 43 04 74 6d 4d 8b 3e e8 5d 54 f4 e0 85 c0 74 0d 80 3d 08 71 1d 00 00
  0f 84 bb 00 00 00 31 c0 <49> 81 7f 08 20 3a 2c a0 75 cc 41 8b 97 50 02 00 00 49 8b 8f a8 00
  <4> [109.613283] RSP: 0018:ffffc9000044bcf8 EFLAGS: 00010246
  <4> [109.613292] RAX: 0000000000000000 RBX: ffffc9000044bdc0 RCX: 0000000000000001
  <4> [109.613302] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff822474a0
  <4> [109.613311] RBP: ffffc9000044bd28 R08: ffff88021e158680 R09: 0000000000000001
  <4> [109.613321] R10: 0000000000000040 R11: 0000000000000000 R12: ffff88021e1641b8
  <4> [109.613331] R13: 0000000000000003 R14: ffff88021e1641b0 R15: 6b6b6b6b6b6b6b6b
  <4> [109.613341] FS:  00007f9c9fc84980(0000) GS:ffff880227a40000(0000) knlGS:0000000000000000
  <4> [109.613352] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  <4> [109.613360] CR2: 00007f9c9fcb8000 CR3: 00000002247d4005 CR4: 00000000000606e0

Fixes: 27836b641c ("dma-buf: remove shared fence staging in reservation object")
Testcase: igt/gem_busy/close-race
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian König <christian.koenig@amd.com>
Cc: Junwei Zhang <Jerry.Zhang@amd.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181026080302.11507-1-chris@chris-wilson.co.uk
2018-10-26 15:42:11 +01:00
Christian König
ca05359f1e dma-buf: allow reserving more than one shared fence slot
Let's support simultaneous submissions to multiple engines.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Link: https://patchwork.kernel.org/patch/10626149/
2018-10-25 13:45:07 +02:00
Christian König
27836b641c dma-buf: remove shared fence staging in reservation object
No need for that any more. Just replace the list when there isn't enough
room any more for the additional fence.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Link: https://patchwork.kernel.org/patch/10626143/
2018-10-25 13:41:16 +02:00
Michel Dänzer
7f43ef9f0d dma-buf: Move BUG_ON from _add_shared_fence to _add_shared_inplace
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 <chris@chris-wilson.co.uk> # v1
Reviewed-by: Christian König <christian.koenig@amd.com> # v1
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180704151405.10357-1-michel@daenzer.net
2018-07-16 20:20:37 +05:30
Thomas Hellstrom
08295b3b5b locking: Implement an algorithm choice for Wound-Wait mutexes
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 <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-doc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Co-authored-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
2018-07-03 09:44:36 +02:00
Dave Airlie
76ea0f334e drm-misc-next for 4.17:
UAPI Changes:
 - drm/vc4: Expose performance counters to userspace (Boris)
 
 Cross-subsystem Changes:
 - MAINTAINERS: Linus to maintain panel-arm-versatile in -misc (Linus)
 
 Core Changes:
 - Only use swiotlb when necessary (Chunming)
 
 Driver Changes:
 - drm/panel: Add support for ARM Versatile panels (Linus)
 - pl111: Improvements around versatile panel support (Linus)
 
 ----------------------------------------
 Tagged on 2018-02-06:
 drm-misc-next for 4.17:
 
 UAPI Changes:
 - Validate mode flags + type (Ville)
 - Deprecate unused mode flags PIXMUX, BCAST (Ville)
 - Deprecate unused mode types BUILTIN, CRTC_C, CLOCK_C, DEFAULT (Ville)
 
 Cross-subsystem Changes:
 - MAINTAINERS: s/Daniel/Maarten/ for drm-misc (Daniel)
 
 Core Changes:
 - gem: Export gem functions for drivers to use (Samuel)
 - bridge: Introduce bridge timings in drm_bridge (Linus)
 - dma-buf: Allow exclusive fence to be bundled in fence array when
 	   calling reservation_object_get_fences_rcu (Christian)
 - dp: Add training pattern 4 and HBR3 support to dp helpers (Manasi)
 - fourcc: Add alpha bit to formats to avoid driver format LUTs (Maxime)
 - mode: Various cleanups + add new device-wide .mode_valid hook (Ville)
 - atomic: Fix state leak when non-blocking commits fail (Leo)
 	  NOTE: IIRC, this was cross-picked to -fixes so it might fall out
 - crc: Allow polling on the data fd (Maarten)
 
 Driver Changes:
 - bridge/vga-dac: Add THS8134* support (Linus)
 - tinydrm: Various MIPI DBI improvements/cleanups (Noralf)
 - bridge/dw-mipi-dsi: Cleanups + use create_packet helper (Brian)
 - drm/sun4i: Add Display Engine frontend support (Maxime)
 - drm/sun4i: Add zpos support + increase num planes from 2 to 4 (Maxime)
 - various: Use drm_mode_get_hv_timing() to fill plane clip rectangle (Ville)
 - stm: Add 8-bit clut support, add dsi phy v1.31 support, +fixes (Phillipe)
 
 Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
 Cc: Chunming Zhou <david1.zhou@amd.com>
 Cc: Samuel Li <Samuel.Li@amd.com>
 Cc: Linus Walleij <linus.walleij@linaro.org>
 Cc: Noralf Trønnes <noralf@tronnes.org>
 Cc: Brian Norris <briannorris@chromium.org>
 Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
 Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
 Cc: Christian König <christian.koenig@amd.com>
 Cc: Manasi Navare <manasi.d.navare@intel.com>
 Cc: Philippe Cornu <philippe.cornu@st.com>
 Cc: Leo (Sunpeng) Li <sunpeng.li@amd.com>
 Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
 Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEfxcpfMSgdnQMs+QqlvcN/ahKBwoFAlqDUjcACgkQlvcN/ahK
 Bwp83Af8D805yWeS/rJ9pLaiaWmfuymMtZVl/IOEssElxFO4d+ya/S4HrcWJQwX6
 KinIQiaytKKe3+TXhVRVVwg7nLBFXzaPey6SvFPCgSEa+Bm+b3v0Uk1ll59UfOzs
 /IhwIYIvUSCqTVAccpoT8X/85JUQ3iP41RbdfbBwUtpvL+XLl/y29Pw1dtV71ZCH
 I3/5zAk3odLd9LuPkyhtg+V1e8pluKlPVGZ0ElOiZ7HlKzc3ekOLNNj563LBHq8y
 b2txi2+h/bfBx7PU5JfP6aOKGGameE79/3UExwW0dJJAHqU728KKs/7OaDu7w0vr
 UlH0cY/Zc461ejPldXXx8hoKIxJ3bw==
 =5EUv
 -----END PGP SIGNATURE-----

Merge tag 'drm-misc-next-2018-02-13' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for 4.17:

UAPI Changes:
- drm/vc4: Expose performance counters to userspace (Boris)

Cross-subsystem Changes:
- MAINTAINERS: Linus to maintain panel-arm-versatile in -misc (Linus)

Core Changes:
- Only use swiotlb when necessary (Chunming)

Driver Changes:
- drm/panel: Add support for ARM Versatile panels (Linus)
- pl111: Improvements around versatile panel support (Linus)

----------------------------------------
Tagged on 2018-02-06:
drm-misc-next for 4.17:

UAPI Changes:
- Validate mode flags + type (Ville)
- Deprecate unused mode flags PIXMUX, BCAST (Ville)
- Deprecate unused mode types BUILTIN, CRTC_C, CLOCK_C, DEFAULT (Ville)

Cross-subsystem Changes:
- MAINTAINERS: s/Daniel/Maarten/ for drm-misc (Daniel)

Core Changes:
- gem: Export gem functions for drivers to use (Samuel)
- bridge: Introduce bridge timings in drm_bridge (Linus)
- dma-buf: Allow exclusive fence to be bundled in fence array when
	   calling reservation_object_get_fences_rcu (Christian)
- dp: Add training pattern 4 and HBR3 support to dp helpers (Manasi)
- fourcc: Add alpha bit to formats to avoid driver format LUTs (Maxime)
- mode: Various cleanups + add new device-wide .mode_valid hook (Ville)
- atomic: Fix state leak when non-blocking commits fail (Leo)
	  NOTE: IIRC, this was cross-picked to -fixes so it might fall out
- crc: Allow polling on the data fd (Maarten)

Driver Changes:
- bridge/vga-dac: Add THS8134* support (Linus)
- tinydrm: Various MIPI DBI improvements/cleanups (Noralf)
- bridge/dw-mipi-dsi: Cleanups + use create_packet helper (Brian)
- drm/sun4i: Add Display Engine frontend support (Maxime)
- drm/sun4i: Add zpos support + increase num planes from 2 to 4 (Maxime)
- various: Use drm_mode_get_hv_timing() to fill plane clip rectangle (Ville)
- stm: Add 8-bit clut support, add dsi phy v1.31 support, +fixes (Phillipe)

Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Chunming Zhou <david1.zhou@amd.com>
Cc: Samuel Li <Samuel.Li@amd.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Brian Norris <briannorris@chromium.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Philippe Cornu <philippe.cornu@st.com>
Cc: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

* tag 'drm-misc-next-2018-02-13' of git://anongit.freedesktop.org/drm/drm-misc: (115 commits)
  drm/radeon: only enable swiotlb path when need v2
  drm/amdgpu: only enable swiotlb alloc when need v2
  drm: add func to get max iomem address v2
  drm/vc4: Expose performance counters to userspace
  drm: Print the pid when debug logging an ioctl error.
  drm/stm: ltdc: remove non-alpha color formats on layer 2 for older hw
  drm/stm: ltdc: add non-alpha color formats
  drm/bridge/synopsys: dsi: Add 1.31 version support
  drm/bridge/synopsys: dsi: Add read feature
  drm/pl111: Support multiple endpoints on the CLCD
  drm/pl111: Support variants with broken VBLANK
  drm/pl111: Support variants with broken clock divider
  drm/pl111: Handle the Versatile RGB/BGR565 mode
  drm/pl111: Properly detect the ARM PL110 variants
  drm/panel: Add support for ARM Versatile panels
  drm/panel: Device tree bindings for ARM Versatile panels
  drm/bridge: Rename argument from crtc to bridge
  drm/crc: Add support for polling on the data fd.
  drm/sun4i: Use drm_mode_get_hv_timing() to populate plane clip rectangle
  drm/rcar-du: Use drm_mode_get_hv_timing() to populate plane clip rectangle
  ...
2018-02-16 09:29:27 +10:00
Christian König
a35f2f34b5 dma-buf: make returning the exclusive fence optional
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.

Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180110125341.3618-1-christian.koenig@amd.com
2018-01-23 12:14:26 -05:00
Christian König
5bffee867d dma-buf: fix reservation_object_wait_timeout_rcu once more v2
We need to set shared_count even if we already have a fence to wait for.

v2: init i to -1 as well

Signed-off-by: Christian König <christian.koenig@amd.com>
Cc: stable@vger.kernel.org
Tested-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180122200003.6665-1-christian.koenig@amd.com
2018-01-23 10:46:39 -05:00
Christian König
ca25fe5efe dma-buf: try to replace a signaled fence in reservation_object_add_shared_inplace
The amdgpu issue to also need signaled fences in the reservation objects should
be fixed by now.

Optimize the handling by replacing a signaled fence when adding a new
shared one.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114142436.1360-2-christian.koenig@amd.com
2017-11-14 12:01:45 -05:00
Christian König
4d9c62e8ce dma-buf: keep only not signaled fence in reservation_object_add_shared_replace v3
The amdgpu issue to also need signaled fences in the reservation objects
should be fixed by now.

Optimize the list by keeping only the not signaled yet fences around.

v2: temporary put the signaled fences at the end of the new container
v3: put the old fence at the end of the new container as well.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114142436.1360-1-christian.koenig@amd.com
2017-11-14 12:00:46 -05:00
Ville Syrjälä
ad46d7b893 dma-buf: Use rcu_assign_pointer() to set rcu protected pointers
Use rcu_assign_pointer() when setting an rcu protected pointer.
This gets rid of another sparse warning.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: linaro-mm-sig@lists.linaro.org
Cc: linux-media@vger.kernel.org
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171102200336.23347-5-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Christian König <christian.koenig@amd.com>.
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
2017-11-09 20:35:12 +02:00
Christian König
39e16ba16c dma-buf: make reservation_object_copy_fences rcu save
Stop requiring that the src reservation object is locked for this operation.

Acked-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1504551766-5093-1-git-send-email-deathsimple@vodafone.de
2017-10-09 11:07:56 -04:00
Christian König
b88fa004e8 dma-buf: fix reservation_object_wait_timeout_rcu to wait correctly v2
With hardware resets in mind it is possible that all shared fences are
signaled, but the exlusive isn't. Fix waiting for everything in this situation.

v2: make sure we always wait for the exclusive fence

Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1502384509-10465-3-git-send-email-alexander.deucher@amd.com
2017-08-14 13:01:25 -04:00
Christian König
7faf952a30 dma-buf: add reservation_object_copy_fences (v2)
Allows us to copy all the fences in a reservation object to another one.

v2: handle NULL src_list

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1502384509-10465-2-git-send-email-alexander.deucher@amd.com
2017-08-14 13:00:49 -04:00
Christian König
f3e31b73a5 dma-buf: dma_fence_put is NULL safe
No need to check.

Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1502141543-13455-2-git-send-email-alexander.deucher@amd.com
2017-08-09 15:01:32 -04:00
Christian König
06a66b5c77 reservation: revert "wait only with non-zero timeout specified (v3)" v2
Reverts commit fb8b7d2b9d
	("reservation: wait only with non-zero timeout specified (v3)")

Otherwise signaling might never be activated on the fences. This can
result in infinite waiting with hardware which has unreliable interrupts.

v2: still return one when the timeout is zero and we don't have any fences.

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> (v1)
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
  [sumits: fix checkpatch warnings]
Link: http://patchwork.freedesktop.org/patch/msgid/1478553376-18575-4-git-send-email-alexander.deucher@amd.com
2016-11-09 00:48:57 +05:30
Chris Wilson
f54d186700 dma-buf: Rename struct fence to dma_fence
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
2016-10-25 14:40:39 +02:00
Chris Wilson
b68d8379c2 dma-buf: Restart reservation_object_test_signaled_rcu() after writes
In order to be completely generic, we have to double check the read
seqlock after acquiring a reference to the fence. If the driver is
allocating fences from a SLAB_DESTROY_BY_RCU, or similar freelist, then
within an RCU grace period a fence may be freed and reallocated. The RCU
read side critical section does not prevent this reallocation, instead
we have to inspect the reservation's seqlock to double check if the
fences have been reassigned as we were acquiring our reference.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829070834.22296-9-chris@chris-wilson.co.uk
2016-10-12 20:00:02 +05:30
Chris Wilson
1cec20f0ea dma-buf: Restart reservation_object_wait_timeout_rcu() after writes
In order to be completely generic, we have to double check the read
seqlock after acquiring a reference to the fence. If the driver is
allocating fences from a SLAB_DESTROY_BY_RCU, or similar freelist, then
within an RCU grace period a fence may be freed and reallocated. The RCU
read side critical section does not prevent this reallocation, instead
we have to inspect the reservation's seqlock to double check if the
fences have been reassigned as we were acquiring our reference.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829070834.22296-8-chris@chris-wilson.co.uk
2016-10-12 19:57:14 +05:30
Chris Wilson
fedf54132d dma-buf: Restart reservation_object_get_fences_rcu() after writes
In order to be completely generic, we have to double check the read
seqlock after acquiring a reference to the fence. If the driver is
allocating fences from a SLAB_DESTROY_BY_RCU, or similar freelist, then
within an RCU grace period a fence may be freed and reallocated. The RCU
read side critical section does not prevent this reallocation, instead
we have to inspect the reservation's seqlock to double check if the
fences have been reassigned as we were acquiring our reference.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829070834.22296-7-chris@chris-wilson.co.uk
2016-10-12 19:57:00 +05:30
Rob Clark
f5bef0b85e reservation: fix small comment typo
Signed-off-by: Rob Clark <robdclark@gmail.com>
[danvet: Mark up as function for proper cross-linking.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1471640134-30888-1-git-send-email-robdclark@gmail.com
2016-08-22 09:22:09 +02:00
Rob Clark
dad6c3945f reservation: add headerdoc comments
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2016-05-31 22:12:43 +05:30
Jagan Teki
5136629dc5 dma-buf: Minor coding style fixes
- WARNING: Missing a blank line after declarations
- WARNING: line over 80 characters
- WARNING: please, no space before tabs

Signed-off-by: Jagan Teki <jteki@openedev.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2015-05-21 11:29:59 +05:30
Michel Dänzer
4eb2440ed6 reservation: Remove shadowing local variable 'ret'
It was causing the return value of fence_is_signaled to be ignored, making
reservation objects signal too early.

Cc: stable@vger.kernel.org
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2015-01-22 16:29:31 +05:30
Jammy Zhou
fb8b7d2b9d reservation: wait only with non-zero timeout specified (v3)
When the timeout value passed to reservation_object_wait_timeout_rcu
is zero, no wait should be done if the fences are not signaled.

Return '1' for idle and '0' for busy if the specified timeout is '0'
to keep consistent with the case of non-zero timeout.

v2: call fence_put if not signaled in the case of timeout==0

v3: switch to reservation_object_test_signaled_rcu

Signed-off-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-By: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
2015-01-22 11:27:57 +05:30
Maarten Lankhorst
3c3b177a93 reservation: add suppport for read-only access using rcu
This adds some extra functions to deal with rcu.

reservation_object_get_fences_rcu() will obtain the list of shared
and exclusive fences without obtaining the ww_mutex.

reservation_object_wait_timeout_rcu() will wait on all fences of the
reservation_object, without obtaining the ww_mutex.

reservation_object_test_signaled_rcu() will test if all fences of the
reservation_object are signaled without using the ww_mutex.

reservation_object_get_excl and reservation_object_get_list require
the reservation object to be held, updating requires
write_seqcount_begin/end. If only the exclusive fence is needed,
rcu_dereference followed by fence_get_rcu can be used, if the shared
fences are needed it's recommended to use the supplied functions.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-By: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-08 13:41:08 -07:00
Maarten Lankhorst
04a5faa8cb reservation: update api and add some helpers
Move the list of shared fences to a struct, and return it in
reservation_object_get_list().
Add reservation_object_get_excl to get the exclusive fence.

Add reservation_object_reserve_shared(), which reserves space
in the reservation_object for 1 more shared fence.

reservation_object_add_shared_fence() and
reservation_object_add_excl_fence() are used to assign a new
fence to a reservation_object pointer, to complete a reservation.

Changes since v1:
- Add reservation_object_get_excl, reorder code a bit.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-08 13:37:35 -07:00
Maarten Lankhorst
35fac7e305 dma-buf: move to drivers/dma-buf
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-08 10:51:06 -07:00