When an entity from application B is killed, drm_sched_entity_kill()
removes all jobs belonging to that entity through
drm_sched_entity_kill_jobs_work(). If application A's job depends on a
scheduled fence from application B's job, and that fence is not properly
signaled during the killing process, application A's dependency cannot be
cleared.
This leads to application A hanging indefinitely while waiting for a
dependency that will never be resolved. Fix this issue by ensuring that
scheduled fences are properly signaled when an entity is killed, allowing
dependent applications to continue execution.
Signed-off-by: Lin.Cao <lincao12@amd.com>
Reviewed-by: Philipp Stanner <phasta@kernel.org>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20250515020713.1110476-1-lincao12@amd.com
Pull drm updates from Dave Airlie:
"Outside of drm there are some rust patches from Danilo who maintains
that area in here, and some pieces for drm header check tests.
The major things in here are a new driver supporting the touchbar
displays on M1/M2, the nova-core stub driver which is just the vehicle
for adding rust abstractions and start developing a real driver inside
of.
xe adds support for SVM with a non-driver specific SVM core
abstraction that will hopefully be useful for other drivers, along
with support for shrinking for TTM devices. I'm sure xe and AMD
support new devices, but the pipeline depth on these things is hard to
know what they end up being in the marketplace!
uapi:
- add mediatek tiled fourcc
- add support for notifying userspace on device wedged
new driver:
- appletbdrm: support for Apple Touchbar displays on m1/m2
- nova-core: skeleton rust driver to develop nova inside off
firmware:
- add some rust firmware pieces
rust:
- add 'LocalModule' type alias
component:
- add helper to query bound status
fbdev:
- fbtft: remove access to page->index
media:
- cec: tda998x: import driver from drm
dma-buf:
- add fast path for single fence merging
tests:
- fix lockdep warnings
atomic:
- allow full modeset on connector changes
- clarify semantics of allow_modeset and drm_atomic_helper_check
- async-flip: support on arbitary planes
- writeback: fix UAF
- Document atomic-state history
format-helper:
- support ARGB8888 to ARGB4444 conversions
buddy:
- fix multi-root cleanup
ci:
- update IGT
dp:
- support extended wake timeout
- mst: fix RAD to string conversion
- increase DPCD eDP control CAP size to 5 bytes
- add DPCD eDP v1.5 definition
- add helpers for LTTPR transparent mode
panic:
- encode QR code according to Fido 2.2
scheduler:
- add parameter struct for init
- improve job peek/pop operations
- optimise drm_sched_job struct layout
ttm:
- refactor pool allocation
- add helpers for TTM shrinker
panel-orientation:
- add a bunch of new quirks
panel:
- convert panels to multi-style functions
- edp: Add support for B140UAN04.4, BOE NV140FHM-NZ, CSW MNB601LS1-3,
LG LP079QX1-SP0V, MNE007QS3-7, STA 116QHD024002, Starry
116KHD024006, Lenovo T14s Gen6 Snapdragon
- himax-hx83102: Add support for CSOT PNA957QT1-1, Kingdisplay
kd110n11-51ie, Starry 2082109qfh040022-50e
- visionox-r66451: use multi-style MIPI-DSI functions
- raydium-rm67200: Add driver for Raydium RM67200
- simple: Add support for BOE AV123Z7M-N17, BOE AV123Z7M-N17
- sony-td4353-jdi: Use MIPI-DSI multi-func interface
- summit: Add driver for Apple Summit display panel
- visionox-rm692e5: Add driver for Visionox RM692E5
bridge:
- pass full atomic state to various callbacks
- adv7511: Report correct capabilities
- it6505: Fix HDCP V compare
- snd65dsi86: fix device IDs
- nwl-dsi: set bridge type
- ti-sn65si83: add error recovery and set bridge type
- synopsys: add HDMI audio support
xe:
- support device-wedged event
- add mmap support for PCI memory barrier
- perf pmu integration and expose per-engien activity
- add EU stall sampling support
- GPU SVM and Xe SVM implementation
- use TTM shrinker
- add survivability mode to allow the driver to do firmware updates
in critical failure states
- PXP HWDRM support for MTL and LNL
- expose package/vram temps over hwmon
- enable DP tunneling
- drop mmio_ext abstraction
- Reject BO evcition if BO is bound to current VM
- Xe suballocator improvements
- re-use display vmas when possible
- add GuC Buffer Cache abstraction
- PCI ID update for Panther Lake and Battlemage
- Enable SRIOV for Panther Lake
- Refactor VRAM manager location
i915:
- enable extends wake timeout
- support device-wedged event
- Enable DP 128b/132b SST DSC
- FBC dirty rectangle support for display version 30+
- convert i915/xe to drm client setup
- Compute HDMI PLLS for rates not in fixed tables
- Allow DSB usage when PSR is enabled on LNL+
- Enable panel replay without full modeset
- Enable async flips with compressed buffers on ICL+
- support luminance based brightness via DPCD for eDP
- enable VRR enable/disable without full modeset
- allow GuC SLPC default strategies on MTL+ for performance
- lots of display refactoring in move to struct intel_display
amdgpu:
- add device wedged event
- support async page flips on overlay planes
- enable broadcast RGB drm property
- add info ioctl for virt mode
- OEM i2c support for RGB lights
- GC 11.5.2 + 11.5.3 support
- SDMA 6.1.3 support
- NBIO 7.9.1 + 7.11.2 support
- MMHUB 1.8.1 + 3.3.2 support
- DCN 3.6.0 support
- Add dynamic workload profile switching for GC 10-12
- support larger VBIOS sizes
- Mark gttsize parameters as deprecated
- Initial JPEG queue resset support
amdkfd:
- add KFD per process flags for setting precision
- sync pasid values between KGD and KFD
- improve GTT/VRAM handling for APUs
- fix user queue validation on GC7/8
- SDMA queue reset support
raedeon:
- rs400 hyperz fix
i2c:
- td998x: drop platform_data, split driver into media and bridge
ast:
- transmitter chip detection refactoring
- vbios display mode refactoring
- astdp: fix connection status and filter unsupported modes
- cursor handling refactoring
imagination:
- check job dependencies with sched helper
ivpu:
- improve command queue handling
- use workqueue for IRQ handling
- add support HW fault injection
- locking fixes
mgag200:
- add support for G200eH5
msm:
- dpu: add concurrent writeback support for DPU 10.x+
- use LTTPR helpers
- GPU:
- Fix obscure GMU suspend failure
- Expose syncobj timeline support
- Extend GPU devcoredump with pagetable info
- a623 support
- Fix a6xx gen1/gen2 indexed-register blocks in gpu snapshot /
devcoredump
- Display:
- Add cpu-cfg interconnect paths on SM8560 and SM8650
- Introduce KMS OMMU fault handler, causing devcoredump snapshot
- Fixed error pointer dereference in msm_kms_init_aspace()
- DPU:
- Fix mode_changing handling
- Add writeback support on SM6150 (QCS615)
- Fix DSC programming in 1:1:1 topology
- Reworked hardware resource allocation, moving it to the CRTC code
- Enabled support for Concurrent WriteBack (CWB) on SM8650
- Enabled CDM blocks on all relevant platforms
- Reworked debugfs interface for BW/clocks debugging
- Clear perf params before calculating bw
- Support YUV formats on writeback
- Fixed double inclusion
- Fixed writeback in YUV formats when using cloned output, Dropped
wb2_formats_rgb
- Corrected dpu_crtc_check_mode_changed and struct dpu_encoder_virt
kerneldocs
- Fixed uninitialized variable in dpu_crtc_kickoff_clone_mode()
- DSI:
- DSC-related fixes
- Rework clock programming
- DSI PHY:
- Fix 7nm (and lower) PHY programming
- Add proper DT schema definitions for DSI PHY clocks
- HDMI:
- Rework the driver, enabling the use of the HDMI Connector
framework
- Bindings:
- Added eDP PHY on SA8775P
nouveau:
- move drm_slave_encoder interface into driver
- nvkm: refactor GSP RPC
- use LTTPR helpers
mediatek:
- HDMI fixup and refinement
- add MT8188 dsc compatible
- MT8365 SoC support
panthor:
- Expose sizes of intenral BOs via fdinfo
- Fix race between reset and suspend
- Improve locking
qaic:
- Add support for AIC200
renesas:
- Fix limits in DT bindings
rockchip:
- support rk3562-mali
- rk3576: Add HDMI support
- vop2: Add new display modes on RK3588 HDMI0 up to 4K
- Don't change HDMI reference clock rate
- Fix DT bindings
- analogix_dp: add eDP support
- fix shutodnw
solomon:
- Set SPI device table to silence warnings
- Fix pixel and scanline encoding
v3d:
- handle clock
vc4:
- Use drm_exec
- Use dma-resv for wait-BO ioctl
- Remove seqno infrastructure
virtgpu:
- Support partial mappings of GEM objects
- Reserve VGA resources during initialization
- Fix UAF in virtgpu_dma_buf_free_obj()
- Add panic support
vkms:
- Switch to a managed modesetting pipeline
- Add support for ARGB8888
- fix UAf
xlnx:
- Set correct DMA segment size
- use mutex guards
- Fix error handling
- Fix docs"
* tag 'drm-next-2025-03-28' of https://gitlab.freedesktop.org/drm/kernel: (1762 commits)
drm/amd/pm: Update feature list for smu_v13_0_6
drm/amdgpu: Add parameter documentation for amdgpu_sync_fence
drm/amdgpu/discovery: optionally use fw based ip discovery
drm/amdgpu/discovery: use specific ip_discovery.bin for legacy asics
drm/amdgpu/discovery: check ip_discovery fw file available
drm/amd/pm: Remove unnecessay UQ10 to UINT conversion
drm/amd/pm: Remove unnecessay UQ10 to UINT conversion
drm/amdgpu/sdma_v4_4_2: update VM flush implementation for SDMA
drm/amdgpu: Optimize VM invalidation engine allocation and synchronize GPU TLB flush
drm/amd/amdgpu: Increase max rings to enable SDMA page ring
drm/amdgpu: Decode deferred error type in gfx aca bank parser
drm/amdgpu/gfx11: Add Cleaner Shader Support for GFX11.5 GPUs
drm/amdgpu/mes: clean up SDMA HQD loop
drm/amdgpu/mes: enable compute pipes across all MEC
drm/amdgpu/mes: drop MES 10.x leftovers
drm/amdgpu/mes: optimize compute loop handling
drm/amdgpu/sdma: guilty tracking is per instance
drm/amdgpu/sdma: fix engine reset handling
drm/amdgpu: remove invalid usage of sched.ready
drm/amdgpu: add cleaner shader trace point
...
Idea is to add helpers for peeking and popping jobs from entities with
the goal of decoupling the hidden assumption in the code that queue_node
is the first element in struct drm_sched_job.
That assumption usually comes in the form of:
while ((job = to_drm_sched_job(spsc_queue_pop(&entity->job_queue))))
Which breaks if the queue_node is re-positioned due to_drm_sched_job
being implemented with a container_of.
This also allows us to remove duplicate definitions of to_drm_sched_job.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Philipp Stanner <phasta@kernel.org>
Signed-off-by: Philipp Stanner <phasta@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250221105038.79665-2-tvrtko.ursulin@igalia.com
Having removed one re-lock cycle on the entity->lock in a patch titled
"drm/sched: Optimise drm_sched_entity_push_job", with only a tiny bit
larger refactoring we can do the same optimisation on the rq->lock.
(Currently both drm_sched_rq_add_entity() and
drm_sched_rq_update_fifo_locked() take and release the same lock.)
To achieve this we make drm_sched_rq_update_fifo_locked() and
drm_sched_rq_add_entity() expect the rq->lock to be held.
We also align drm_sched_rq_update_fifo_locked(),
drm_sched_rq_add_entity() and
drm_sched_rq_remove_fifo_locked() function signatures, by adding rq as a
parameter to the latter.
v2:
* Fix after rebase of the series.
* Avoid naming inconsistency between drm_sched_rq_add/remove. (Christian)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Luben Tuikov <ltuikov89@gmail.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Philipp Stanner <pstanner@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241016122013.7857-6-tursulin@igalia.com
drm_sched_entity_kill_jobs_cb() logic is omitting the last fence popped
from the dependency array that was waited upon before
drm_sched_entity_kill() was called (drm_sched_entity::dependency field),
so we're basically waiting for all dependencies except one.
In theory, this wait shouldn't be needed because resources should have
their users registered to the dma_resv object, thus guaranteeing that
future jobs wanting to access these resources wait on all the previous
users (depending on the access type, of course). But we want to keep
these explicit waits in the kill entity path just in case.
Let's make sure we keep all dependencies in the array in
drm_sched_job_dependency(), so we can iterate over the array and wait
in drm_sched_entity_kill_jobs_cb().
We also make sure we wait on drm_sched_fence::finished if we were
originally asked to wait on drm_sched_fence::scheduled. In that case,
we assume the intent was to delegate the wait to the firmware/GPU or
rely on the pipelining done at the entity/scheduler level, but when
killing jobs, we really want to wait for completion not just scheduling.
v2:
- Don't evict deps in drm_sched_job_dependency()
v3:
- Always wait for drm_sched_fence::finished fences in
drm_sched_entity_kill_jobs_cb() when we see a sched_fence
v4:
- Fix commit message
- Fix a use-after-free bug
v5:
- Flag deps on which we should only wait for the scheduled event
at insertion time
v6:
- Back to v4 implementation
- Add Christian's R-b
Cc: Frank Binns <frank.binns@imgtec.com>
Cc: Sarah Walker <sarah.walker@imgtec.com>
Cc: Donald Robson <donald.robson@imgtec.com>
Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Suggested-by: "Christian König" <christian.koenig@amd.com>
Reviewed-by: "Christian König" <christian.koenig@amd.com>
Acked-by: Luben Tuikov <luben.tuikov@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230619071921.3465992-1-boris.brezillon@collabora.com
[Why]
drm_sched_entity_add_dependency_cb ignores the scheduled fence and return false.
If entity's dependency is a scheduler error fence and drm_sched_stop is called
due to TDR, drm_sched_entity_pop_job will wait for the dependency infinitely.
[How]
Do not wait or ignore the scheduled error fence, add drm_sched_entity_wakeup
callback for the dependency with scheduled error fence.
Signed-off-by: ZhenGuo Yin <zhenguo.yin@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Rename drm_sched_wakeup() to drm_sched_wakeup_if_canqueue() since the former
is misleading, as it wakes up the GPU scheduler _only if_ more jobs can be
queued to the underlying hardware.
This distinction is important to make, since the wake conditional in the GPU
scheduler thread wakes up when other conditions are also true, e.g. when there
are jobs to be cleaned. For instance, a user might want to wake up the
scheduler only because there are more jobs to clean, but whether we can queue
more jobs is irrelevant.
v2: Separate "canqueue" to "can_queue". (Alex D.)
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <Alexander.Deucher@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Link: https://lore.kernel.org/r/20230517233550.377847-2-luben.tuikov@amd.com
Reviewed-by: Alex Deucher <Alexander.Deucher@amd.com>
It already happend a few times that patches slipped through which
implemented access to an entity through a job that was already removed
from the entities queue. Since jobs and entities might have different
lifecycles, this can potentially cause UAF bugs.
In order to make it obvious that a jobs entity pointer shouldn't be
accessed after drm_sched_entity_pop_job() was called successfully, set
the jobs entity pointer to NULL once the job is removed from the entity
queue.
Moreover, debugging a potential NULL pointer dereference is way easier
than potentially corrupted memory through a UAF.
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://lore.kernel.org/r/20230418100453.4433-1-dakr@redhat.com
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
The drm_sched_entity_kill() is invoked twice by drm_sched_entity_destroy()
while userspace process is exiting or being killed. First time it's invoked
when sched entity is flushed and second time when entity is released. This
causes a lockup within wait_for_completion(entity_idle) due to how completion
API works.
Calling wait_for_completion() more times than complete() was invoked is a
error condition that causes lockup because completion internally uses
counter for complete/wait calls. The complete_all() must be used instead
in such cases.
This patch fixes lockup of Panfrost driver that is reproducible by killing
any application in a middle of 3d drawing operation.
Fixes: 2fdb8a8f07 ("drm/scheduler: rework entity flush, kill and fini")
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck
Link: https://patchwork.freedesktop.org/patch/msgid/20221123001303.533968-1-dmitry.osipenko@collabora.com
The drm_sched_entity_kill() is invoked twice by drm_sched_entity_destroy()
while userspace process is exiting or being killed. First time it's invoked
when sched entity is flushed and second time when entity is released. This
causes a lockup within wait_for_completion(entity_idle) due to how completion
API works.
Calling wait_for_completion() more times than complete() was invoked is a
error condition that causes lockup because completion internally uses
counter for complete/wait calls. The complete_all() must be used instead
in such cases.
This patch fixes lockup of Panfrost driver that is reproducible by killing
any application in a middle of 3d drawing operation.
Fixes: 2fdb8a8f07 ("drm/scheduler: rework entity flush, kill and fini")
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123001303.533968-1-dmitry.osipenko@collabora.com
drm-misc-next for 6.2:
UAPI Changes:
- Documentation for page-flip flags
Cross-subsystem Changes:
- dma-buf: Add unlocked variant of vmapping and attachment-mapping
functions
Core Changes:
- atomic-helpers: CRTC primary plane test fixes
- connector: TV API consistency improvements, cmdline parsing
improvements
- crtc-helpers: Introduce drm_crtc_helper_atomic_check() helper
- edid: Fixes for HFVSDB parsing,
- fourcc: Addition of the Vivante tiled modifier
- makefile: Sort and reorganize the objects files
- mode_config: Remove fb_base from drm_mode_config_funcs
- sched: Add a module parameter to change the scheduling policy,
refcounting fix for fences
- tests: Sort the Kunit tests in the Makefile, improvements to the
DP-MST tests
- ttm: Remove unnecessary drm_mm_clean() call
Driver Changes:
- New driver: ofdrm
- Move all drivers to a common dma-buf locking convention
- bridge:
- adv7533: Remove dynamic lane switching
- it6505: Runtime PM support
- ps8640: Handle AUX defer messages
- tc358775: Drop soft-reset over I2C
- ast: Atomic Gamma LUT Support, Convert to SHMEM, various
improvements
- lcdif: Support for YUV planes
- mgag200: Fix PLL Setup on some revisions
- udl: Modesetting improvements, hot-unplug support
- vc4: Fix support for PAL-M
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20221020072405.g3o4hxuk75gmeumw@houat
When many entities are competing for the same run queue
on the same scheduler, we observe an unusually long wait
times and some jobs get starved. This has been observed on GPUVis.
The issue is due to the Round Robin policy used by schedulers
to pick up the next entity's job queue for execution. Under stress
of many entities and long job queues within entity some
jobs could be stuck for very long time in it's entity's
queue before being popped from the queue and executed
while for other entities with smaller job queues a job
might execute earlier even though that job arrived later
then the job in the long queue.
Fix:
Add FIFO selection policy to entities in run queue, chose next entity
on run queue in such order that if job on one entity arrived
earlier then job on another entity the first job will start
executing earlier regardless of the length of the entity's job
queue.
v2:
Switch to rb tree structure for entities based on TS of
oldest job waiting in the job queue of an entity. Improves next
entity extraction to O(1). Entity TS update
O(log N) where N is the number of entities in the run-queue
Drop default option in module control parameter.
v3:
Various cosmetical fixes and minor refactoring of fifo update function. (Luben)
v4:
Switch drm_sched_rq_select_entity_fifo to in order search (Luben)
v5: Fix up drm_sched_rq_select_entity_fifo loop (Luben)
v6: Add missing drm_sched_rq_remove_fifo_locked
v7: Fix ts sampling bug and more cosmetic stuff (Luben)
v8: Fix module parameter string (Luben)
Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Direct Rendering Infrastructure - Development <dri-devel@lists.freedesktop.org>
Cc: AMD Graphics <amd-gfx@lists.freedesktop.org>
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Tested-by: Yunxiang Li (Teddy) <Yunxiang.Li@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220930041258.1050247-1-luben.tuikov@amd.com
Probelm:
Singlaning one sched fence from within another's sched
fence singal callback generates lockdep splat because
the both have same lockdep class of their fence->lock
Fix:
Fix bellow stack by rescheduling to irq work of
signaling and killing of jobs that left when entity is killed.
[11176.741181] dump_stack+0x10/0x12
[11176.741186] __lock_acquire.cold+0x208/0x2df
[11176.741197] lock_acquire+0xc6/0x2d0
[11176.741204] ? dma_fence_signal+0x28/0x80
[11176.741212] _raw_spin_lock_irqsave+0x4d/0x70
[11176.741219] ? dma_fence_signal+0x28/0x80
[11176.741225] dma_fence_signal+0x28/0x80
[11176.741230] drm_sched_fence_finished+0x12/0x20 [gpu_sched]
[11176.741240] drm_sched_entity_kill_jobs_cb+0x1c/0x50 [gpu_sched]
[11176.741248] dma_fence_signal_timestamp_locked+0xac/0x1a0
[11176.741254] dma_fence_signal+0x3b/0x80
[11176.741260] drm_sched_fence_finished+0x12/0x20 [gpu_sched]
[11176.741268] drm_sched_job_done.isra.0+0x7f/0x1a0 [gpu_sched]
[11176.741277] drm_sched_job_done_cb+0x12/0x20 [gpu_sched]
[11176.741284] dma_fence_signal_timestamp_locked+0xac/0x1a0
[11176.741290] dma_fence_signal+0x3b/0x80
[11176.741296] amdgpu_fence_process+0xd1/0x140 [amdgpu]
[11176.741504] sdma_v4_0_process_trap_irq+0x8c/0xb0 [amdgpu]
[11176.741731] amdgpu_irq_dispatch+0xce/0x250 [amdgpu]
[11176.741954] amdgpu_ih_process+0x81/0x100 [amdgpu]
[11176.742174] amdgpu_irq_handler+0x26/0xa0 [amdgpu]
[11176.742393] __handle_irq_event_percpu+0x4f/0x2c0
[11176.742402] handle_irq_event_percpu+0x33/0x80
[11176.742408] handle_irq_event+0x39/0x60
[11176.742414] handle_edge_irq+0x93/0x1d0
[11176.742419] __common_interrupt+0x50/0xe0
[11176.742426] common_interrupt+0x80/0x90
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Suggested-by: Christian König <christian.koenig@amd.com>
Tested-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://www.spinics.net/lists/dri-devel/msg321250.html
It might be good enough on x86 with just READ_ONCE, but the write side
should then at least be WRITE_ONCE because x86 has total store order.
It's definitely not enough on arm.
Fix this proplery, which means
- explain the need for the barrier in both places
- point at the other side in each comment
Also pull out the !sched_list case as the first check, so that the
code flow is clearer.
While at it sprinkle some comments around because it was very
non-obvious to me what's actually going on here and why.
Note that we really need full barriers here, at first I thought
store-release and load-acquire on ->last_scheduled would be enough,
but we actually requiring ordering between that and the queue state.
v2: Put smp_rmp() in the right place and fix up comment (Andrey)
Reviewed-by: Christian König <christian.koenig@amd.com>
Acked-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210805104705.862416-4-daniel.vetter@ffwll.ch
