After much hair pulling, resort to preallocating the ppGTT entries on
init to circumvent the apparent lack of PD invalidate following the
write to PP_DCLV upon switching mm between contexts (and here the same
context after binding new objects). However, the details of that PP_DCLV
invalidate are still unknown, and it appears we need to reload the mm
twice to cover over a timing issue. Worrying.
Fixes: 3dc007fe9b ("drm/i915/gtt: Downgrade gen7 (ivb, byt, hsw) back to aliasing-ppgtt")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191129201328.1398583-1-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
Since we cannot allocate underneath the vm->mutex (it is used in the
direct-reclaim paths), we need to shift the allocations off into a
mutexless worker with fence recursion prevention. To know when we need
this protection, we mark up the address spaces that do allocate before
insertion. In the future, we may wish to extend the async bind scheme to
more than just allocations.
v2: s/vm->bind_alloc/vm->bind_async_flags/
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/20191004134015.13204-3-chris@chris-wilson.co.uk
The sg_table for our backing store might contain addresses from
stolen-memory or in the future local-memory, at which point this is no
longer a dma-iterator. As a consequence we should now break on NULL
iter.sgp, instead of dmap == 0 which is considered an invalid dma
address.
As a bonus, gcc much prefers this construct,
Function old new delta
gen8_ggtt_insert_entries 211 192 -19
gen6_ggtt_insert_entries 292 262 -30
i915_error_object_create 996 954 -42
Signed-off-by: Matthew Auld <matthew.auld@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/20190829201919.21493-1-matthew.auld@intel.com
When under severe stress for GTT mappable space, the LRU eviction model
falls off a cliff. We spend all our time scanning the much larger
non-mappable area searching for something within the mappable zone we can
evict. Turn this on its head by only using the full vma for the object if
it is already pinned in the mappable zone or there is sufficient *free*
space to accommodate it (prioritizing speedy reuse). If there is not,
immediately fall back to using small chunks (tilerow for GTT mmap, single
pages for pwrite/relocation) and using random eviction before doing a full
search.
Testcase: igt/gem_concurrent_blt
References: https://bugs.freedesktop.org/show_bug.cgi?id=110848
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/20190821123234.19194-1-chris@chris-wilson.co.uk
Replace mixed "_fini"/"_cleanup"/"_cleanup_hw" suffixes found in names
of functions called from i915_driver_release() with "_release" suffix
consistently. This provides better code readability, especially
helpful when trying to work out which phase the code is in.
Functions names starting with "i915_driver_", i.e., those defined in
drivers/gpu/dri/i915/i915_drv.c, just have their "cleanup" or "fini"
parts of their names replaced with the "_release" suffix, while names
of functions coming from other source files have been suffixed with
"_driver_release" to avoid ambiguity with other possible .release entry
points.
v2: early_probe pairs better with late_release (Chris)
v3: fix typo in commit message (Joonas)
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190712112429.740-5-janusz.krzysztofik@linux.intel.com
Instead of relying on the caller holding struct_mutex across the
allocation, push the allocation under a tree of spinlocks stored inside
the page tables. Not only should this allow us to avoid struct_mutex
here, but it will allow multiple users to lock independent ranges for
concurrent allocations, and operate independently. This is vital for
pushing the GTT manipulation into a background thread where dependency
on struct_mutex is verboten, and for allowing other callers to avoid
struct_mutex altogether.
v2: Restore lost GEM_BUG_ON for removing too many PTE from
gen6_ppgtt_clear_range.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190604153830.19096-1-chris@chris-wilson.co.uk
It was noted that we made the same mistake for VM_ID as for object
handles, whereby we ensured that we only allocated a single handle for
one ppgtt. This has the unfortunate consequence for userspace that they
need to reference count the handles to avoid destroying an active ID. If
we allow multiple handles to the same ppgtt, userspace can freely
unreference any handle they own without fear of destroying the same
handle in use elsewhere.
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/20190425054333.27299-1-chris@chris-wilson.co.uk
GuC and HuC depend on struct_mutex for device reinitialization. Moving
away from this dependency requires perma-pinning the firmware images in
GGTT. The upper portion of the GuC address space has a sizeable hole
(several MB) that is inaccessible by GuC. Reserve this range within GGTT
as it can comfortably hold GuC/HuC firmware images.
v2: Reserve node rather than insert (Chris)
Simpler determination of node start/size (Daniele)
Move reserve/release out to intel_guc.* files
v3: Reserve starting at GUC_GGTT_TOP only and bail if this
fails (Chris)
Signed-off-by: Fernando Pacheco <fernando.pacheco@intel.com>
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/20190419230015.18121-3-fernando.pacheco@intel.com
In preparation to making the ppGTT binding for a context explicit (to
facilitate reusing the same ppGTT between different contexts), allow the
user to create and destroy named ppGTT.
v2: Replace global barrier for swapping over the ppgtt and tlbs with a
local context barrier (Tvrtko)
v3: serialise with struct_mutex; it's lazy but required dammit
v4: Rewrite igt_ctx_shared_exec to be more different (aimed to be more
similarly, turned out different!)
v5: Fix up test unwind for aliasing-ppgtt (snb)
v6: Tighten language for uapi struct drm_i915_gem_vm_control.
v7: Patch the context image for runtime ppgtt switching!
Testcase: igt/gem_vm_create
Testcase: igt/gem_ctx_param/vm
Testcase: igt/gem_ctx_clone/vm
Testcase: igt/gem_ctx_shared
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/20190322092325.5883-2-chris@chris-wilson.co.uk
In the next patch, we are introducing a broad virtual engine to encompass
multiple physical engines, losing the 1:1 nature of BIT(engine->id). To
reflect the broader set of engines implied by the virtual instance, lets
store the full bitmask.
v2: Use intel_engine_mask_t (s/ring_mask/engine_mask/)
v3: Tvrtko voted for moah churn so teach everyone to not mention ring
and use $class$instance throughout.
v4: Comment upon the disparity in bspec for using VCS1,VCS2 in gen8 and
VCS[0-4] in later gen. We opt to keep the code consistent and use
0-index naming throughout.
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/20190305180332.30900-1-chris@chris-wilson.co.uk
