As preempt-to-busy leaves the request on the HW as the resubmission is
processed, that request may complete in the background and even cause a
second virtual request to enter queue. This second virtual request
breaks our "single request in the virtual pipeline" assumptions.
Furthermore, as the virtual request may be completed and retired, we
lose the reference the virtual engine assumes is held. Normally, just
removing the request from the scheduler queue removes it from the
engine, but the virtual engine keeps track of its singleton request via
its ve->request. This pointer needs protecting with a reference.
v2: Drop unnecessary motion of rq->engine = owner
Fixes: 22b7a426bb ("drm/i915/execlists: Preempt-to-busy")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190923152844.8914-1-chris@chris-wilson.co.uk
(cherry picked from commit b647c7df01)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Due to the nature of preempt-to-busy the execlists active tracking and
the schedule queue may become temporarily desync'ed (between resubmission
to HW and its ack from HW). This means that we may have unwound a
request and passed it back to the virtual engine, but it is still
inflight on the HW and may even result in a GPU hang. If we detect that
GPU hang and try to reset, the hanging request->engine will no longer
match the current engine, which means that the request is not on the
execlists active list and we should not try to find an older incomplete
request. Given that we have deduced this must be a request on a virtual
engine, it is the single active request in the context and so must be
guilty (as the context is still inflight, it is prevented from being
executed on another engine as we process the reset).
Fixes: 22b7a426bb ("drm/i915/execlists: Preempt-to-busy")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190923152844.8914-2-chris@chris-wilson.co.uk
(cherry picked from commit cb2377a919)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
If we are asked to submit a completed request, just move it onto the
active-list without modifying it's payload. If we try to emit the
modified payload of a completed request, we risk racing with the
ring->head update during retirement which may advance the head past our
breadcrumb and so we generate a warning for the emission being behind
the RING_HEAD.
v2: Commentary for the sneaky, shared responsibility between functions.
v3: Spelling mistakes and bonus assertion
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190923110056.15176-3-chris@chris-wilson.co.uk
(cherry picked from commit c0bb487dc1)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Force bonded requests to run on distinct engines so that they cannot be
shuffled onto the same engine where timeslicing will reverse the order.
A bonded request will often wait on a semaphore signaled by its master,
creating an implicit dependency -- if we ignore that implicit dependency
and allow the bonded request to run on the same engine and before its
master, we will cause a GPU hang. [Whether it will hang the GPU is
debatable, we should keep on timeslicing and each timeslice should be
"accidentally" counted as forward progress, in which case it should run
but at one-half to one-third speed.]
We can prevent this inversion by restricting which engines we allow
ourselves to jump to upon preemption, i.e. baking in the arrangement
established at first execution. (We should also consider capturing the
implicit dependency using i915_sched_add_dependency(), but first we need
to think about the constraints that requires on the execution/retirement
ordering.)
Fixes: 8ee36e048c ("drm/i915/execlists: Minimalistic timeslicing")
References: ee1136908e ("drm/i915/execlists: Virtual engine bonding")
Testcase: igt/gem_exec_balancer/bonded-slice
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190923152844.8914-3-chris@chris-wilson.co.uk
(cherry picked from commit e2144503bf)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
As we may unwind incomplete requests (for preemption) prior to
processing the CSB and the schedule-out events, we may update rq->engine
(resetting it to point back to the parent virtual engine) prior to
calling execlists_schedule_out(), invalidating the assertion that the
request still points to the inflight engine. (The likelihood of this is
increased if the CSB interrupt processing is pushed to the ksoftirqd for
being too slow and direct submission overtakes it.)
Tvrtko summarised it as:
"So unwind from direct submission resets rq->engine and races with
process_csb from the tasklet which notices request has actually
completed."
Reported-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Fixes: df40306902 ("drm/i915/execlists: Lift process_csb() out of the irq-off spinlock")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190907105046.19934-1-chris@chris-wilson.co.uk
(cherry picked from commit d810583fc2)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Pull drm updates from Dave Airlie:
"This is the main pull request for 5.4-rc1 merge window. I don't think
there is anything outstanding so next week should just be fixes, but
we'll see if I missed anything. I landed some fixes earlier in the
week but got delayed writing summary and sending it out, due to a mix
of sick kid and jetlag!
There are some fixes pending, but I'd rather get the main merge out of
the way instead of delaying it longer.
It's also pretty large in commit count and new amd header file size.
The largest thing is four new amdgpu products (navi12/14, arcturus and
renoir APU support).
Otherwise it's pretty much lots of work across the board, i915 has
started landing tigerlake support, lots of icelake fixes and lots of
locking reworking for future gpu support, lots of header file rework
(drmP.h is nearly gone), some old legacy hacks (DRM_WAIT_ON) have been
put into the places they are needed.
uapi:
- content protection type property for HDCP
core:
- rework include dependencies
- lots of drmP.h removals
- link rate calculation robustness fix
- make fb helper map only when required
- add connector->DDC adapter link
- DRM_WAIT_ON removed
- drop DRM_AUTH usage from drivers
dma-buf:
- reservation object fence helper
dma-fence:
- shrink dma_fence struct
- merge signal functions
- store timestamps in dma_fence
- selftests
ttm:
- embed drm_get_object struct into ttm_buffer_object
- release_notify callback
bridges:
- sii902x - audio graph card support
- tc358767 - aux data handling rework
- ti-snd64dsi86 - debugfs support, DSI mode flags support
panels:
- Support for GiantPlus GPM940B0, Sharp LQ070Y3DG3B, Ortustech
COM37H3M, Novatek NT39016, Sharp LS020B1DD01D, Raydium RM67191, Boe
Himax8279d, Sharp LD-D5116Z01B
- TI nspire, NEC NL8048HL11, LG Philips LB035Q02, Sharp LS037V7DW01,
Sony ACX565AKM, Toppoly TD028TTEC1 Toppoly TD043MTEA1
i915:
- Initial tigerlake platform support
- Locking simplification work, general all over refactoring.
- Selftests
- HDCP debug info improvements
- DSI properties
- Icelake display PLL fixes, colorspace fixes, bandwidth fixes, DSI
suspend/resume
- GuC fixes
- Perf fixes
- ElkhartLake enablement
- DP MST fixes
- GVT - command parser enhancements
amdgpu:
- add wipe memory on release flag for buffer creation
- Navi12/14 support (may be marked experimental)
- Arcturus support
- Renoir APU support
- mclk DPM for Navi
- DC display fixes
- Raven scatter/gather support
- RAS support for GFX
- Navi12 + Arcturus power features
- GPU reset for Picasso
- smu11 i2c controller support
amdkfd:
- navi12/14 support
- Arcturus support
radeon:
- kexec fix
nouveau:
- improved display color management
- detect lack of GPU power cables
vmwgfx:
- evicition priority support
- remove unused security feature
msm:
- msm8998 display support
- better async commit support for cursor updates
etnaviv:
- per-process address space support
- performance counter fixes
- softpin support
mcde:
- DCS transfers fix
exynos:
- drmP.h cleanup
lima:
- reduce logging
kirin:
- misc clenaups
komeda:
- dual-link support
- DT memory regions
hisilicon:
- misc fixes
imx:
- IPUv3 image converter fixes
- 32-bit RGB V4L2 pixel format support
ingenic:
- more support for panel related cases
mgag200:
- cursor support fix
panfrost:
- export GPU features register to userspace
- gpu heap allocations
- per-fd address space support
pl111:
- CLD pads wiring support removed from DT
rockchip:
- rework to use DRM PSR helpers
- fix bug in VOP_WIN_GET macro
- DSI DT binding rework
sun4i:
- improve support for color encoding and range
- DDC enabled GPIO
tinydrm:
- rework SPI support
- improve MIPI-DBI support
- moved to drm/tiny
vkms:
- rework CRC tracking
dw-hdmi:
- get_eld and i2s improvements
gm12u320:
- misc fixes
meson:
- global code cleanup
- vpu feature detect
omap:
- alpha/pixel blend mode properties
rcar-du:
- misc fixes"
* tag 'drm-next-2019-09-18' of git://anongit.freedesktop.org/drm/drm: (2112 commits)
drm/nouveau/bar/gm20b: Avoid BAR1 teardown during init
drm/nouveau: Fix ordering between TTM and GEM release
drm/nouveau/prime: Extend DMA reservation object lock
drm/nouveau: Fix fallout from reservation object rework
drm/nouveau/kms/nv50-: Don't create MSTMs for eDP connectors
drm/i915: Use NOEVICT for first pass on attemping to pin a GGTT mmap
drm/i915: to make vgpu ppgtt notificaiton as atomic operation
drm/i915: Flush the existing fence before GGTT read/write
drm/i915: Hold irq-off for the entire fake lock period
drm/i915/gvt: update RING_START reg of vGPU when the context is submitted to i915
drm/i915/gvt: update vgpu workload head pointer correctly
drm/mcde: Fix DSI transfers
drm/msm: Use the correct dma_sync calls harder
drm/msm: remove unlikely() from WARN_ON() conditions
drm/msm/dsi: Fix return value check for clk_get_parent
drm/msm: add atomic traces
drm/msm/dpu: async commit support
drm/msm: async commit support
drm/msm: split power control from prepare/complete_commit
drm/msm: add kms->flush_commit()
...
We need the rename of reservation_object to dma_resv.
The solution on this merge came from linux-next:
From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Wed, 14 Aug 2019 12:48:39 +1000
Subject: [PATCH] drm: fix up fallout from "dma-buf: rename reservation_object to dma_resv"
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
---
drivers/gpu/drm/i915/gt/intel_engine_pool.c | 8 ++++----
3 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pool.c b/drivers/gpu/drm/i915/gt/intel_engine_pool.c
index 03d90b49584a..4cd54c569911 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_pool.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_pool.c
@@ -43,12 +43,12 @@ static int pool_active(struct i915_active *ref)
{
struct intel_engine_pool_node *node =
container_of(ref, typeof(*node), active);
- struct reservation_object *resv = node->obj->base.resv;
+ struct dma_resv *resv = node->obj->base.resv;
int err;
- if (reservation_object_trylock(resv)) {
- reservation_object_add_excl_fence(resv, NULL);
- reservation_object_unlock(resv);
+ if (dma_resv_trylock(resv)) {
+ dma_resv_add_excl_fence(resv, NULL);
+ dma_resv_unlock(resv);
}
err = i915_gem_object_pin_pages(node->obj);
which is a simplified version from a previous one which had:
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
drm-misc-next for 5.4:
UAPI Changes:
Cross-subsystem Changes:
Core Changes:
- dma-buf: add reservation_object_fences helper, relax
reservation_object_add_shared_fence, remove
reservation_object seq number (and then
restored)
- dma-fence: Shrinkage of the dma_fence structure,
Merge dma_fence_signal and dma_fence_signal_locked,
Store the timestamp in struct dma_fence in a union with
cb_list
Driver Changes:
- More dt-bindings YAML conversions
- More removal of drmP.h includes
- dw-hdmi: Support get_eld and various i2s improvements
- gm12u320: Few fixes
- meson: Global cleanup
- panfrost: Few refactors, Support for GPU heap allocations
- sun4i: Support for DDC enable GPIO
- New panels: TI nspire, NEC NL8048HL11, LG Philips LB035Q02,
Sharp LS037V7DW01, Sony ACX565AKM, Toppoly TD028TTEC1
Toppoly TD043MTEA1
Signed-off-by: Dave Airlie <airlied@redhat.com>
[airlied: fixup dma_resv rename fallout]
From: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190819141923.7l2adietcr2pioct@flea
The timestamp and the cb_list are mutually exclusive, the cb_list can
only be added to prior to being signaled (and once signaled we drain),
while the timestamp is only valid upon being signaled. Both the
timestamp and the cb_list are only valid while the fence is alive, and
as soon as no references are held can be replaced by the rcu_head.
By reusing the union for the timestamp, we squeeze the base dma_fence
struct to 64 bytes on x86-64.
v2: Sort the union chronologically
Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian König <christian.koenig@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>.
Link: https://patchwork.freedesktop.org/patch/msgid/20190817153022.5749-1-chris@chris-wilson.co.uk
If we only call process_csb() from the tasklet, though we lose the
ability to bypass ksoftirqd interrupt processing on direct submission
paths, we can push it out of the irq-off spinlock.
The penalty is that we then allow schedule_out to be called concurrently
with schedule_in requiring us to handle the usage count (baked into the
pointer itself) atomically.
As we do kick the tasklets (via local_bh_enable()) after our submission,
there is a possibility there to see if we can pull the local softirq
processing back from the ksoftirqd.
v2: Store the 'switch_priority_hint' on submission, so that we can
safely check during process_csb().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190816171608.11760-1-chris@chris-wilson.co.uk
We use timeline->mutex to protect modifications to
context->active_count, and the associated enable/disable callbacks.
Due to complications with engine-pm barrier there is a path where we used
a "superlock" to provide serialised protect and so could not
unconditionally assert with lockdep that it was always held. However,
we can mark the mutex as taken (noting that we may be nested underneath
ourselves) which means we can be reassured the right timeline->mutex is
always treated as held and let lockdep roam free.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190816121000.8507-1-chris@chris-wilson.co.uk
In preparation for removing struct_mutex from around context retirement,
we need to make timeline pinning and unpinning safe. Since multiple
engines/contexts can share a single timeline, we cannot rely on
borrowing the context mutex (otherwise we could state that the timeline
is only pinned/unpinned inside the context pin/unpin and so guarded by
it). However, we only perform a sequence of atomic operations inside the
timeline pin/unpin and the sequence of those operations is safe for a
concurrent unpin / pin, so we can relax the struct_mutex requirement.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190815205709.24285-3-chris@chris-wilson.co.uk
