Add migrate layer functions to access VRAM and update
xe_ttm_access_memory to use for non-visible access and large (more than
16k) BO access. 8G devcoreump on BMG observed 3 minute CPU copy time vs.
3s GPU copy time.
v4:
- Fix non-page aligned accesses
- Add support for small / unaligned access
- Update commit message indicating migrate used for large accesses (Auld)
- Fix warning in xe_res_cursor for non-zero offset
v5:
- Fix 32 bit build (CI)
v6:
- Rebase and use SVM migration copy functions
v7:
- Fix build error (CI)
v8:
- Remove ifdef around VRAM copy functions (CI)
- Use break statement in dma unmmaping (Jonathan)
- Use if/else rather than goto (Jonathan)
- Use single return point (Jonathan)
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://lore.kernel.org/r/20250423171725.597955-3-matthew.brost@intel.com
Building the xe driver for i386 results in a link time warning:
x86_64-linux-ld: drivers/gpu/drm/xe/xe_migrate.o: in function `xe_migrate_vram':
xe_migrate.c:(.text+0x1e15): undefined reference to `__udivdi3'
Avoid this by using DIV_U64_ROUND_UP() instead of DIV_ROUND_UP(). The driver
is unlikely to be used on 32=bit hardware, so the extra cost here is not
too important.
Fixes: 9c44fd5f6e ("drm/xe: Add migrate layer functions for SVM support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20250324210612.2927194-1-arnd@kernel.org
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Change the scope of the migrate subsystem to be dev managed instead of
drm managed.
The parent pci struct &device, that the xe struct &drm_device is a part
of, gets removed when a hot unplug is triggered, which causes the
underlying iommu group to get destroyed as well.
The migrate subsystem, which handles the lifetime of the page-table tree
(pt) BO, doesn't get a chance to keep the BO back during the hot unplug,
as all the references to DRM haven't been put back.
When all the references to DRM are indeed put back later, the migrate
subsystem tries to put back the pt BO. Since the underlying iommu group
has been already destroyed, a kernel NULL ptr dereference takes place
while attempting to keep back the pt BO.
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/3914
Suggested-by: Thomas Hellstrom <thomas.hellstrom@intel.com>
Reviewed-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250326151929.1495972-1-aradhya.bhatia@intel.com
Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
Although all current Xe2 platforms support FlatCCS, we probably
shouldn't assume that will be universally true forever. In the past
we've had platforms like PVC that didn't support compression, and the
same could show up again at some point in the future. Future-proof the
migration code by adding an explicit check for FlatCCS support to the
condition that decides whether to use a compressed PAT index for
migration.
While we're at it, we can drop the IS_DGFX check since it's redundant
with the src_is_vram check (only dGPUs have VRAM).
Cc: Akshata Jahagirdar <akshata.jahagirdar@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Akshata Jahagirdar <akshata.jahagirdar@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240726171757.2728819-2-matthew.d.roper@intel.com
Xe2+ has unified compression (exactly one compression mode/format),
where compression is now controlled via PAT at PTE level.
This simplifies KMD operations, as it can now decompress freely
without concern for the buffer's original compression format—unlike DG2,
which had multiple compression formats and thus required copying the
raw CCS state during VRAM eviction. In addition mixed VRAM and system
memory buffers were not supported with compression enabled.
On Xe2 dGPU compression is still only supported with VRAM, however we
can now support compression with VRAM and system memory buffers,
with GPU access being seamless underneath. So long as when doing
VRAM -> system memory the KMD uses compressed -> uncompressed,
to decompress it. This also allows CPU access to such buffers,
assuming that userspace first decompress the corresponding
pages being accessed.
If the pages are already in system memory then KMD would have already
decompressed them. When restoring such buffers with sysmem -> VRAM
the KMD can't easily know which pages were originally compressed,
so we always use uncompressed -> uncompressed here.
With this it also means we can drop all the raw CCS handling on such
platforms (including needing to allocate extra CCS storage).
In order to support this we now need to have two different identity
mappings for compressed and uncompressed VRAM.
In this patch, we set up the additional identity map for the VRAM with
compressed pat_index. We then select the appropriate mapping during
migration/clear. During eviction (vram->sysmem), we use the mapping
from compressed -> uncompressed. During restore (sysmem->vram), we need
the mapping from uncompressed -> uncompressed.
Therefore, we need to have two different mappings for compressed and
uncompressed vram. We set up an additional identity map for the vram
with compressed pat_index.
We then select the appropriate mapping during migration/clear.
v2: Formatting nits, Updated code to match recent changes in
xe_migrate_prepare_vm(). (Matt)
v3: Move identity map loop to a helper function. (Matt Brost)
v4: Split helper function in different patch, and
add asserts and nits. (Matt Brost)
v5: Convert the 2 bool arguments of pte_update_size to flags
argument (Matt Brost)
v6: Formatting nits (Matt Brost)
Signed-off-by: Akshata Jahagirdar <akshata.jahagirdar@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b00db5c7267e54260cb6183ba24b15c1e6ae52a3.1721250309.git.akshata.jahagirdar@intel.com
This aligns with the uAPI of an array of binds or single bind that
results in multiple GPUVA ops to be considered a single atomic
operations.
The design is roughly:
- xe_vma_ops is a list of xe_vma_op (GPUVA op)
- each xe_vma_op resolves to 0-3 PT ops
- xe_vma_ops creates a single job
- if at any point during binding a failure occurs, xe_vma_ops contains
the information necessary unwind the PT and VMA (GPUVA) state
v2:
- add missing dma-resv slot reservation (CI, testing)
v4:
- Fix TLB invalidation (Paulo)
- Add missing xe_sched_job_last_fence_add/test_dep check (Inspection)
v5:
- Invert i, j usage (Matthew Auld)
- Add helper to test and add job dep (Matthew Auld)
- Return on anything but -ETIME for cpu bind (Matthew Auld)
- Return -ENOBUFS if suballoc of BB fails due to size (Matthew Auld)
- s/do/Do (Matthew Auld)
- Add missing comma (Matthew Auld)
- Do not assign return value to xe_range_fence_insert (Matthew Auld)
v6:
- s/0x1ff/MAX_PTE_PER_SDI (Matthew Auld, CI)
- Check to large of SA in Xe to avoid triggering WARN (Matthew Auld)
- Fix checkpatch issues
v7:
- Rebase
- Support more than 510 PTEs updates in a bind job (Paulo, mesa testing)
v8:
- Rebase
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240704041652.272920-5-matthew.brost@intel.com
The flags stored in the BO grew over time without following
much a naming pattern. First of all, get rid of the _BIT suffix that was
banned from everywhere else due to the guideline in
drivers/gpu/drm/i915/i915_reg.h that xe kind of follows:
Define bits using ``REG_BIT(N)``. Do **not** add ``_BIT`` suffix to the name.
Here the flags aren't for a register, but it's good practice to keep it
consistent.
Second divergence on names is the use or not of "CREATE". This is
because most of the flags are passed to xe_bo_create*() family of
functions, changing its behavior. However, since the flags are also
stored in the bo itself and checked elsewhere in the code, it seems
better to just omit the CREATE part.
With those 2 guidelines, all the flags are given the form
XE_BO_FLAG_<FLAG_NAME> with the following commands:
git grep -le "XE_BO_" -- drivers/gpu/drm/xe | xargs sed -i \
-e "s/XE_BO_\([_A-Z0-9]*\)_BIT/XE_BO_\1/g" \
-e 's/XE_BO_CREATE_/XE_BO_FLAG_/g'
git grep -le "XE_BO_" -- drivers/gpu/drm/xe | xargs sed -i -r \
-e 's/XE_BO_(DEFER_BACKING|SCANOUT|FIXED_PLACEMENT|PAGETABLE|NEEDS_CPU_ACCESS|NEEDS_UC|INTERNAL_TEST|INTERNAL_64K|GGTT_INVALIDATE)/XE_BO_FLAG_\1/g'
And then the defines in drivers/gpu/drm/xe/xe_bo.h are adjusted to
follow the coding style.
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240322142702.186529-3-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
This function does not build on 32-bit targets when the compiler
fails to reduce DIV_ROUND_UP() into a shift:
ld.lld: error: undefined symbol: __aeabi_uldivmod
>>> referenced by xe_migrate.c
>>> drivers/gpu/drm/xe/xe_migrate.o:(pte_update_size) in archive vmlinux.a
There are two instances in this function. Change the first to
use an open-coded shift with the same behavior, and the second
one to a 32-bit calculation, which is sufficient here as the size
is never more than 2^32 pages (16TB).
Fixes: 237412e453 ("drm/xe: Enable 32bits build")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240226124736.1272949-3-arnd@kernel.org
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
The pat table entry associated with XE_CACHE_WB is coherent whereas
XE_CACHE_NONE is non coherent. Migration expects the coherency
with cpu therefore use the coherent entry XE_CACHE_WB for
buffers not supporting compression. For read/write to flat ccs region
the issue is not related to coherency with cpu. The hardware expects
the pat index associated with GPUVA for indirect access to be
compression enabled hence use XE_CACHE_NONE_COMPRESSION.
v2
- Fix the argument to emit_pte, pass the bool directly. (Thomas)
v3
- Rebase
- Update commit message (Matt)
v4
- Add a Fixes: tag. (Thomas)
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Fixes: 65ef8dbad1 ("drm/xe/xe2: Update emit_pte to use compression enabled PAT index")
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240119041826.1670496-1-himal.prasad.ghimiray@intel.com
Although MI_STORE_DATA_IMM's "length" field is 10-bits, 0x3FE is
considered the largest legal value accepted. Since that instruction
field is always encoded in (val-2) format, this translates to 0x400
dwords for the true maximum length of the instruction. Subtracting the
instruction header (1 dword) and address (2 dwords), that leaves 0x3FD
dwords (i.e., 0x1FE qwords) for PTE values.
Bspec: 60246, 45753
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20240111220238.1467572-2-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Since the migrate code is using the identity map for addressing VRAM,
copy chunks may become as small as 64K if the VRAM resource is fragmented.
However, a chunk size smaller that 1MiB may lead to the *next* chunk's
offset into the CCS metadata backup memory may not be page-aligned, and
the XY_CTRL_SURF_COPY_BLT command can't handle that, and even if it could,
the current code doesn't handle the offset calculaton correctly.
To fix this, make sure we align the size of VRAM copy chunks to 1MiB. If
the remaining data to copy is smaller than that, that's not a problem,
so use the remaining size. If the VRAM copy cunk becomes fragmented due
to the size alignment restriction, don't use the identity map, but instead
emit PTEs into the page-table like we do for system memory.
v2:
- Rebase
v3:
- Future proof somewhat by taking into account the real data size to
flat CCS metadata size ratio. (Matt Roper)
- Invert a couple of if-statements for better readability.
- Fix support for 4K-granularity VRAM sizes. (Tested on DG1).
v4:
- Fix up code comments
- Fix debug printout format typo.
v5:
- Add a Fixes: tag.
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Fixes: e89b384cde ("drm/xe/migrate: Update emit_pte to cope with a size level than 4k")
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/20240110163415.524165-1-thomas.hellstrom@linux.intel.com
Setting of exec_queue user extensions is moved from the end of the ioctl
function earlier, into __xe_exec_queue_alloc().
This fixes bug in that the USM attributes for access counters were being
applied too late, and effectively were ignored.
However, in order to apply user extensions this early, we can no longer
call q->ops functions. Instead, make it more efficient. The user extension
functions can simply update the q->sched_props values and they will be
applied by the backend during q->ops->init().
v2: minor changes for readability (Matt)
Signed-off-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
After exec_queue has been created, we cannot simply modify q->priority.
This needs to be done by the backend via q->ops. However in this case,
it would be more efficient to simply pass a flag when creating the
exec_queue and set the desired priority upfront during queue creation.
To that end: new flag EXEC_QUEUE_FLAG_HIGH_PRIORITY is introduced.
The priority field is moved to be with other scheduling properties and
is now exec_queue.sched_props.priority. This is no longer set to initial
value by the backend, but is now set within __xe_exec_queue_create().
Fixes: b4eecedc75 ("drm/xe: Fix potential deadlock handling page faults")
Signed-off-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
- Clear flat ccs during user bo creation.
- copy ccs meta data between flat ccs and bo during eviction and
restore.
- Add a bool field ccs_cleared in bo, true means ccs region of bo is
already cleared.
v2:
- Rebase.
v3:
- Maintain order of xe_bo_move_notify for ttm_bo_type_sg.
v4:
- xe_migrate_copy can be used to copy src to dst bo on igfx too.
Add a bool which handles only ccs metadata copy.
v5:
- on dgfx ccs should be cleared even if the bo is not compression enabled.
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>