If the move or clear operation somehow fails, and the memory underneath
is not cleared, like when moving to lmem, then we currently fallback to
memcpy or memset. However with small-BAR systems this fallback might no
longer be possible. For now we use the set_wedged sledgehammer if we
ever encounter such a scenario, and mark the object as borked to plug
any holes where access to the memory underneath can happen. Add some
basic selftests to exercise this.
v2:
- In the selftests make sure we grab the runtime pm around the reset.
Also make sure we grab the reset lock before checking if the device
is wedged, since the wedge might still be in-progress and hence the
bit might not be set yet.
- Don't wedge or put the object into an unknown state, if the request
construction fails (or similar). Just returning an error and
skipping the fallback should be safe here.
- Make sure we wedge each gt. (Thomas)
- Peek at the unknown_state in io_reserve, that way we don't have to
export or hand roll the fault_wait_for_idle. (Thomas)
- Add the missing read-side barriers for the unknown_state. (Thomas)
- Some kernel-doc fixes. (Thomas)
v3:
- Tweak the ordering of the set_wedged, also add FIXME.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220629174350.384910-11-matthew.auld@intel.com
Don't wait sync while migrating, but rather make the GPU blit await the
dependencies and add a moving fence to the object.
This also enables asynchronous VRAM management in that on eviction,
rather than waiting for the moving fence to expire before freeing VRAM,
it is freed immediately and the fence is stored with the VRAM manager and
handed out to newly allocated objects to await before clears and swapins,
or for kernel objects before setting up gpu vmas or mapping.
To collect dependencies before migrating, add a set of utilities that
coalesce these to a single dma_fence.
What is still missing for fully asynchronous operation is asynchronous vma
unbinding, which is still to be implemented.
This commit substantially reduces execution time in the gem_lmem_swapping
test.
v2:
- Make a couple of functions static.
v4:
- Fix some style issues (Matthew Auld)
- Audit and add more checks for ghost objects (Matthew Auld)
- Add more documentation for the i915_deps utility (Mattew Auld)
- Simplify the i915_deps_sync() function
v6:
- Re-check for fence signaled before returning -EBUSY (Matthew Auld)
- Use dma_resv_iter_is_exclusive() (Matthew Auld)
- Await all dma-resv fences before a migration blit (Matthew Auld)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211122214554.371864-6-thomas.hellstrom@linux.intel.com
We are about to introduce failsafe- and asynchronous migration and
ttm moves.
This will add complexity and code to the TTM move code so it makes sense
to split it out to a separate file to make the i915 TTM code easer to
digest.
Split the i915 TTM move code out and since we will have to change the name
of the gpu_binds_iomem() and cpu_maps_iomem() functions anyway,
we alter the name of gpu_binds_iomem() to i915_ttm_gtt_binds_lmem() which
is more reflecting what it is used for.
With this we also add some more documentation. Otherwise there should be
no functional change.
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211104110718.688420-2-thomas.hellstrom@linux.intel.com
Just evict unpinned objects to system. For pinned LMEM objects,
make a backup system object and blit the contents to that.
Backup is performed in three steps,
1: Opportunistically evict evictable objects using the gpu blitter.
2: After gt idle, evict evictable objects using the gpu blitter. This will
be modified in an upcoming patch to backup pinned objects that are not used
by the blitter itself.
3: Backup remaining pinned objects using memcpy.
Also move uC suspend to after 2) to make sure we have a functional GuC
during 2) if using GuC submission.
v2:
- Major refactor to make sure gem_exec_suspend@hang-SX subtests work, and
suspend / resume works with a slightly modified GuC submission enabling
patch series.
v3:
- Fix a potential use-after-free (Matthew Auld)
- Use i915_gem_object_create_shmem() instead of
i915_gem_object_create_region (Matthew Auld)
- Minor simplifications (Matthew Auld)
- Fix up kerneldoc for i195_ttm_restore_region().
- Final lmem_suspend() call moved to i915_gem_backup_suspend from
i915_gem_suspend_late, since the latter gets called at driver unload
and we don't unnecessarily want to run it at that time.
v4:
- Interface change of ttm- & lmem suspend / resume functions to use
flags rather than bools. (Matthew Auld)
- Completely drop the i915_gem_backup_suspend change (Matthew Auld)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210922062527.865433-5-thomas.hellstrom@linux.intel.com
For some specialised objects we might need something larger than the
regions min_page_size due to some hw restriction, and slightly more
hairy is needing something smaller with the guarantee that such objects
will never be inserted into any GTT, which is the case for the paging
structures.
This also fixes how we setup the BO page_alignment, if we later migrate
the object somewhere else. For example if the placements are {SMEM,
LMEM}, then we might get this wrong. Pushing the min_page_size behaviour
into the manager should fix this.
v2(Thomas): push the default page size behaviour into buddy_man, and let
the user override it with the page-alignment, which looks cleaner
v3: rebase on ttm sys changes
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625103824.558481-1-matthew.auld@intel.com
Most logical place to introduce TTM buffer objects is as an i915
gem object backend. We need to add some ops to account for added
functionality like delayed delete and LRU list manipulation.
Initially we support only LMEM and SYSTEM memory, but SYSTEM
(which in this case means evicted LMEM objects) is not
visible to i915 GEM yet. The plan is to move the i915 gem system region
over to the TTM system memory type in upcoming patches.
We set up GPU bindings directly both from LMEM and from the system region,
as there is no need to use the legacy TTM_TT memory type. We reserve
that for future porting of GGTT bindings to TTM.
Remove the old lmem backend.
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210610070152.572423-2-thomas.hellstrom@linux.intel.com
