History log of /linux-master/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c
Revision Date Author Comments
# 115cdcca 07-Aug-2023 Jonathan Cavitt <jonathan.cavitt@intel.com>

drm/i915: Make i915_coherent_map_type GT-centric

Refactor i915_coherent_map_type to be GT-centric rather than
device-centric. Each GT may require different coherency
handling due to hardware workarounds.

Since the function now takes a GT instead of the i915, the function is
renamed and moved to the gt folder.

Suggested-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Acked-by: Fei Yang <fei.yang@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230801153242.2445478-3-jonathan.cavitt@intel.com
Link: https://patchwork.freedesktop.org/patch/msgid/20230807121957.598420-3-andi.shyti@linux.intel.com


# 9275277d 09-May-2023 Fei Yang <fei.yang@intel.com>

drm/i915: use pat_index instead of cache_level

Currently the KMD is using enum i915_cache_level to set caching policy for
buffer objects. This is flaky because the PAT index which really controls
the caching behavior in PTE has far more levels than what's defined in the
enum. In addition, the PAT index is platform dependent, having to translate
between i915_cache_level and PAT index is not reliable, and makes the code
more complicated.

From UMD's perspective there is also a necessity to set caching policy for
performance fine tuning. It's much easier for the UMD to directly use PAT
index because the behavior of each PAT index is clearly defined in Bspec.
Having the abstracted i915_cache_level sitting in between would only cause
more ambiguity. PAT is expected to work much like MOCS already works today,
and by design userspace is expected to select the index that exactly
matches the desired behavior described in the hardware specification.

For these reasons this patch replaces i915_cache_level with PAT index. Also
note, the cache_level is not completely removed yet, because the KMD still
has the need of creating buffer objects with simple cache settings such as
cached, uncached, or writethrough. For kernel objects, cache_level is used
for simplicity and backward compatibility. For Pre-gen12 platforms PAT can
have 1:1 mapping to i915_cache_level, so these two are interchangeable. see
the use of LEGACY_CACHELEVEL.

One consequence of this change is that gen8_pte_encode is no longer working
for gen12 platforms due to the fact that gen12 platforms has different PAT
definitions. In the meantime the mtl_pte_encode introduced specfically for
MTL becomes generic for all gen12 platforms. This patch renames the MTL
PTE encode function into gen12_pte_encode and apply it to all gen12. Even
though this change looks unrelated, but separating them would temporarily
break gen12 PTE encoding, thus squash them in one patch.

Special note: this patch changes the way caching behavior is controlled in
the sense that some objects are left to be managed by userspace. For such
objects we need to be careful not to change the userspace settings.There
are kerneldoc and comments added around obj->cache_coherent, cache_dirty,
and how to bypass the checkings by i915_gem_object_has_cache_level. For
full understanding, these changes need to be looked at together with the
two follow-up patches, one disables the {set|get}_caching ioctl's and the
other adds set_pat extension to the GEM_CREATE uAPI.

Bspec: 63019

Cc: Chris Wilson <chris.p.wilson@linux.intel.com>
Signed-off-by: Fei Yang <fei.yang@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230509165200.1740-3-fei.yang@intel.com


# bfe53be2 29-Jun-2022 Matthew Auld <matthew.auld@intel.com>

drm/i915/ttm: handle blitter failure on DG2

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


# a7ce8f82 20-Apr-2022 Matthew Auld <matthew.auld@intel.com>

drm/i915: consider min_page_size when migrating

We can only force migrate an object if the existing object size is
compatible with the new destinations min_page_size for the region.
Currently we blow up with something like:

[ 2857.497462] kernel BUG at drivers/gpu/drm/i915/gt/intel_migrate.c:431!
[ 2857.497497] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 2857.497502] CPU: 1 PID: 8921 Comm: i915_selftest Tainted: G U W 5.18.0-rc1-drm-tip+ #27
[ 2857.497513] RIP: 0010:emit_pte.cold+0x11a/0x17e [i915]
[ 2857.497646] Code: 00 48 c7 c2 f0 cd c1 a0 48 c7 c7 e9 99 bd a0 e8 d2 77 5d e0 bf 01 00 00 00 e8 08 47 5d e0 31 f6 bf 09 00 00 00 e8 3c 7b 4d e0 <0f> 0b 48 c7 c1 e0 2a c5 a0 ba 34 00 00 00 48 c7 c6 00 ce c1 a0 48
[ 2857.497654] RSP: 0018:ffffc900000f7748 EFLAGS: 00010246
[ 2857.497658] RAX: 0000000000000000 RBX: ffffc900000f77c8 RCX: 0000000000000006
[ 2857.497662] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000009
[ 2857.497665] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
[ 2857.497668] R10: 0000000000022302 R11: ffff88846dea08f0 R12: 0000000000010000
[ 2857.497672] R13: 0000000001880000 R14: 000000000000081b R15: ffff888106b7c040
[ 2857.497675] FS: 00007f0d4c4e0600(0000) GS:ffff88845da80000(0000) knlGS:0000000000000000
[ 2857.497679] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2857.497682] CR2: 00007f113966c088 CR3: 0000000211e60003 CR4: 00000000003706e0
[ 2857.497686] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 2857.497689] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 2857.497692] Call Trace:
[ 2857.497694] <TASK>
[ 2857.497697] intel_context_migrate_copy+0x1e5/0x4f0 [i915]

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Nirmoy Das <nirmoy.das@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220420181613.70033-1-matthew.auld@intel.com


# 1d7f5e6c 22-Dec-2021 Christian König <christian.koenig@amd.com>

drm/i915: drop bo->moving dependency

That should now be handled by the common dma_resv framework.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: intel-gfx@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220407085946.744568-13-christian.koenig@amd.com


# 73511edf 09-Nov-2021 Christian König <christian.koenig@amd.com>

dma-buf: specify usage while adding fences to dma_resv obj v7

Instead of distingting between shared and exclusive fences specify
the fence usage while adding fences.

Rework all drivers to use this interface instead and deprecate the old one.

v2: some kerneldoc comments suggested by Daniel
v3: fix a missing case in radeon
v4: rebase on nouveau changes, fix lockdep and temporary disable warning
v5: more documentation updates
v6: separate internal dma_resv changes from this patch, avoids to
disable warning temporary, rebase on upstream changes
v7: fix missed case in lima driver, minimize changes to i915_gem_busy_ioctl

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220407085946.744568-3-christian.koenig@amd.com


# c8d4c18b 16-Nov-2021 Christian König <christian.koenig@amd.com>

dma-buf/drivers: make reserving a shared slot mandatory v4

Audit all the users of dma_resv_add_excl_fence() and make sure they
reserve a shared slot also when only trying to add an exclusive fence.

This is the next step towards handling the exclusive fence like a
shared one.

v2: fix missed case in amdgpu
v3: and two more radeon, rename function
v4: add one more case to TTM, fix i915 after rebase

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220406075132.3263-2-christian.koenig@amd.com


# fa732088 18-Mar-2022 Andi Shyti <andi.shyti@linux.intel.com>

drm/i915: Rename INTEL_REGION_LMEM with INTEL_REGION_LMEM_0

With the upcoming multitile support each tile will have its own
local memory. Mark the current LMEM with the suffix '0' to
emphasise that it belongs to the root tile.

Suggested-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220318233938.149744-2-andi.shyti@linux.intel.com


# 950505ca 10-Jan-2022 Thomas Hellström <thomas.hellstrom@linux.intel.com>

drm/i915: Asynchronous migration selftest

Add a selftest to exercise asynchronous migration and -unbining.
Extend the gem_migrate selftest to perform the migrations while
depending on a spinner and a bound vma set up on the migrated
buffer object.

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/20220110172219.107131-6-thomas.hellstrom@linux.intel.com


# 1a9c4db4 14-Dec-2021 Michał Winiarski <michal.winiarski@intel.com>

drm/i915/gem: Use to_gt() helper

Use to_gt() helper consistently throughout the codebase.
Pure mechanical s/i915->gt/to_gt(i915). No functional changes.

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214193346.21231-6-andi.shyti@linux.intel.com


# 2b0a750c 03-Nov-2021 Thomas Hellström <thomas.hellstrom@linux.intel.com>

drm/i915/ttm: Failsafe migration blits

If the initial fill blit or copy blit of an object fails, the old
content of the data might be exposed and read as soon as either CPU- or
GPU PTEs are set up to point at the pages.

Intercept the blit fence with an async callback that checks the
blit fence for errors and if there are errors performs an async cpu blit
instead. If there is a failure to allocate the async dma_fence_work,
allocate it on the stack and sync wait for the blit to complete.

Add selftests that simulate gpu blit failures and failure to allocate
the async dma_fence_work.

A previous version of this pach used dma_fence_work, now that's
opencoded which adds more code but might lower the latency
somewhat in the common non-error case.

v3:
- Style fixes (Matthew Auld)
v4:
- Use "#if IS_ENABLED()" instead of #ifdef (Matthew Auld)
v5:
- Fix an issue where we, if the dependency was already signaled, might
end up waiting for a memcpy fence that would never signal.
v6:
- Add a missing i915_ttm_memcpy_release() (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/20211104110718.688420-3-thomas.hellstrom@linux.intel.com


# f3170ba8 22-Jul-2021 Jason Ekstrand <jason@jlekstrand.net>

drm/i915/gem: Check object_can_migrate from object_migrate

We don't roll them together entirely because there are still a couple
cases where we want a separate can_migrate check. For instance, the
display code checks that you can migrate a buffer to LMEM before it
accepts it in fb_create. The dma-buf import code also uses it to do an
early check and return a different error code if someone tries to attach
a LMEM-only dma-buf to another driver.

However, no one actually wants to call object_migrate when can_migrate
has failed. The stated intention is for self-tests but none of those
actually take advantage of this unsafe migration.

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Cc: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210723172142.3273510-2-jason@jlekstrand.net


# d22632c8 25-Jun-2021 Matthew Auld <matthew.auld@intel.com>

drm/i915: support forcing the page size with lmem

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


# bf74a18c 29-Jun-2021 Matthew Auld <matthew.auld@intel.com>

drm/i915/gem: Introduce a selftest for the gem object migrate functionality

A selftest for the gem object migrate functionality. Slightly adapted
from the original by Matthew to the new interface and new fill blit
code.

v4:
- Initialize buffers and check contents after migration
(Suggested by Matthew Auld)
- Perform async migration (if implemented) in the igt_lmem_pages_migrate
test
- Test also migration to the current region.

Co-developed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com> #v3
Link: https://patchwork.freedesktop.org/patch/msgid/20210629151203.209465-3-thomas.hellstrom@linux.intel.com