Forgo the struct_mutex serialisation for i915_active, and interpose its
own mutex handling for active/retire.
This is a multi-layered sleight-of-hand. First, we had to ensure that no
active/retire callbacks accidentally inverted the mutex ordering rules,
nor assumed that they were themselves serialised by struct_mutex. More
challenging though, is the rule over updating elements of the active
rbtree. Instead of the whole i915_active now being serialised by
struct_mutex, allocations/rotations of the tree are serialised by the
i915_active.mutex and individual nodes are serialised by the caller
using the i915_timeline.mutex (we need to use nested spinlocks to
interact with the dma_fence callback lists).
The pain point here is that instead of a single mutex around execbuf, we
now have to take a mutex for active tracker (one for each vma, context,
etc) and a couple of spinlocks for each fence update. The improvement in
fine grained locking allowing for multiple concurrent clients
(eventually!) should be worth it in typical loads.
v2: Add some comments that barely elucidate anything :(
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-6-chris@chris-wilson.co.uk
Replace the struct_mutex requirement for pinning the i915_vma with the
local vm->mutex instead. Note that the vm->mutex is tainted by the
shrinker (we require unbinding from inside fs-reclaim) and so we cannot
allocate while holding that mutex. Instead we have to preallocate
workers to do allocate and apply the PTE updates after we have we
reserved their slot in the drm_mm (using fences to order the PTE writes
with the GPU work and with later unbind).
In adding the asynchronous vma binding, one subtle requirement is to
avoid coupling the binding fence into the backing object->resv. That is
the asynchronous binding only applies to the vma timeline itself and not
to the pages as that is a more global timeline (the binding of one vma
does not need to be ordered with another vma, nor does the implicit GEM
fencing depend on a vma, only on writes to the backing store). Keeping
the vma binding distinct from the backing store timelines is verified by
a number of async gem_exec_fence and gem_exec_schedule tests. The way we
do this is quite simple, we keep the fence for the vma binding separate
and only wait on it as required, and never add it to the obj->resv
itself.
Another consequence in reducing the locking around the vma is the
destruction of the vma is no longer globally serialised by struct_mutex.
A natural solution would be to add a kref to i915_vma, but that requires
decoupling the reference cycles, possibly by introducing a new
i915_mm_pages object that is own by both obj->mm and vma->pages.
However, we have not taken that route due to the overshadowing lmem/ttm
discussions, and instead play a series of complicated games with
trylocks to (hopefully) ensure that only one destruction path is called!
v2: Add some commentary, and some helpers to reduce patch churn.
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/20191004134015.13204-4-chris@chris-wilson.co.uk
Before we submit the first context to HW, we need to construct a valid
image of the register state. This layout is defined by the HW and should
match the layout generated by HW when it saves the context image.
Asserting that this should be equivalent should help avoid any undefined
behaviour and verify that we haven't missed anything important!
Of course, having insisted that the initial register state within the
LRC should match that returned by HW, we need to ensure that it does.
v2: Drop the RELATIVE_MMIO flag from gen11, we ignore it for
constructing the lrc image.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190924145950.3011-1-chris@chris-wilson.co.uk
The request->timeline is only valid until the request is retired (i.e.
before it is completed). Upon retiring the request, the context may be
unpinned and freed, and along with it the timeline may be freed. We
therefore need to be very careful when chasing rq->timeline that the
pointer does not disappear beneath us. The vast majority of users are in
a protected context, either during request construction or retirement,
where the timeline->mutex is held and the timeline cannot disappear. It
is those few off the beaten path (where we access a second timeline) that
need extra scrutiny -- to be added in the next patch after first adding
the warnings about dangerous access.
One complication, where we cannot use the timeline->mutex itself, is
during request submission onto hardware (under spinlocks). Here, we want
to check on the timeline to finalize the breadcrumb, and so we need to
impose a second rule to ensure that the request->timeline is indeed
valid. As we are submitting the request, it's context and timeline must
be pinned, as it will be used by the hardware. Since it is pinned, we
know the request->timeline must still be valid, and we cannot submit the
idle barrier until after we release the engine->active.lock, ergo while
submitting and holding that spinlock, a second thread cannot release the
timeline.
v2: Don't be lazy inside selftests; hold the timeline->mutex for as long
as we need it, and tidy up acquiring the timeline with a bit of
refactoring (i915_active_add_request)
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/20190919111912.21631-1-chris@chris-wilson.co.uk
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()
...
Currently, if there is time remaining before the start of the loop, we
do one full iteration over many possible different chunks within the
object. A full loop may take 50+s (depending on speed of indirect GTT
mmapings) and we try separately with LINEAR, X and Y -- at which point
igt times out. If we check more frequently, we will interrupt the loop
upon our timeout -- it is hard to argue for as this significantly reduces
the test coverage as we dramatically reduce the runtime. In practical
terms, the coverage we should prioritise is in using different fence
setups, forcing verification of the tile row computations over the
current preference of checking extracting chunks. Though the exhaustive
search is great given an infinite timeout, to improve our current
coverage, we also add a randomised smoketest of partial mmaps. So let's
do both, add a randomised smoketest of partial tiling chunks and the
exhaustive (though time limited) search for failures.
Even in adding another subtest, we should shave 100s off BAT! (With,
hopefully, no loss in coverage, at least over multiple runs.)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190910121009.13431-1-chris@chris-wilson.co.uk
obj->pin_global was originally used as a means to keep the shrinker off
the active scanout, but we use the vma->pin_count itself for that and
the obj->frontbuffer to delay shrinking active framebuffers. The other
role that obj->pin_global gained was for spotting display objects inside
GEM and working harder to keep those coherent; for which we can again
simply inspect obj->frontbuffer directly.
Coming up next, we will want to manipulate the pin_global counter
outside of the principle locks, so would need to make pin_global atomic.
However, since obj->frontbuffer is already managed atomically, it makes
sense to use that the primary key for display objects instead of having
pin_global.
Ville pointed out the principle difference is that obj->frontbuffer is
set for as long as an intel_framebuffer is attached to an object, but
obj->pin_global was only raised for as long as the object was active. In
practice, this means that we consider the object as being on the scanout
for longer than is strictly required, causing us to be more proactive in
flushing -- though it should be true that we would have flushed
eventually when the back became the front, except that on the flip path
that flush is async but when hit from another ioctl it will be
synchronous.
v2: i915_gem_object_is_framebuffer()
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190902040303.14195-5-chris@chris-wilson.co.uk
The CS pre-parser can pre-fetch commands across memory sync points and
starting from gen12 it is able to pre-fetch across BB_START and BB_END
boundaries as well, so when we emit gpu relocs the pre-parser might
fetch the target location of the reloc before the memory write lands.
The parser can't pre-fetch across the ctx switch, so we use a separate
context to guarantee that the memory is synchronized before the parser
can get to it.
Note that there is no risk of the CS doing a lite restore from the reloc
context to the user context, even if the two have the same hw_id,
because since gen11 the CS also checks the LRCA when deciding if it can
lite-restore.
v2: limit new context to gen12+, release in eb_destroy, add a comment
in emit_fini_breadcrumb (Chris).
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190827185805.21799-1-daniele.ceraolospurio@intel.com
In order for the Braswell top-level PD to remain the same from the time
of request construction to its submission onto HW, as we may be
asynchronously rewriting the page tables (thus changing the expected
register state after having already stored the old addresses in the
request), the top level PD must be preallocated.
So wave goodbye to our lazy allocation of those 4x2 pages.
v2: A little bit of write-flushing required (presumably it always has
been required, but now we are more susceptible and it is showing up!)
v3: Put back the forced-PD-reload on every batch, we can't survive
without it and explicitly marking the context for PD reload makes
Braswell turn nasty.
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/20190823141421.2398-1-chris@chris-wilson.co.uk
