We now support a per-gt uncore, yet we're not able to infer which GT
we're operating upon. Let's store a backpointer for now.
At this point the early initialization of the gt needs to be
broken in two parts where the first is needed to assign to the gt
the i915 private data pointer and the uncore. A temporary
function has been made and the two parts are
__intel_gt_init_early() and intel_gt_init_early(). This split
will be fixed in the future with the multitile patch.
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214193346.21231-2-andi.shyti@linux.intel.com
Testing the stealing of guc ids is hard from user space as we have 64k
guc_ids. Add a selftest, which artificially reduces the number of guc
ids, and forces a steal.
The test creates a spinner which is used to block all subsequent
submissions until it completes. Next, a loop creates a context and a NOP
request each iteration until the guc_ids are exhausted (request creation
returns -EAGAIN). The spinner is ended, unblocking all requests created
in the loop. At this point all guc_ids are exhausted but are available
to steal. Try to create another request which should successfully steal
a guc_id. Wait on last request to complete, idle GPU, verify a guc_id
was stolen via a counter, and exit the test. Test also artificially
reduces the number of guc_ids so the test runs in a timely manner.
v2:
(John Harrison)
- s/stole/stolen
- Fix some wording in test description
- Rework indexing into context array
- Add test description to commit message
- Fix typo in commit message
(Checkpatch)
- s/guc/(guc) in NUMBER_MULTI_LRC_GUC_ID
v3:
(John Harrison)
- Set array value to NULL after extracting error
- Fix a few typos in comments / error messages
- Delete redundant comment in commit message
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214170500.28569-8-matthew.brost@intel.com
While attempting to debug a CT deadlock issue in various CI failures
(most easily reproduced with gem_ctx_create/basic-files), I was seeing
CPU deadlock errors being reported. This were because the context
destroy loop was blocking waiting on H2G space from inside an IRQ
spinlock. There no was deadlock as such, it's just that the H2G queue
was full of context destroy commands and GuC was taking a long time to
process them. However, the kernel was seeing the large amount of time
spent inside the IRQ lock as a dead CPU. Various Bad Things(tm) would
then happen (heartbeat failures, CT deadlock errors, outstanding H2G
WARNs, etc.).
Re-working the loop to only acquire the spinlock around the list
management (which is all it is meant to protect) rather than the
entire destroy operation seems to fix all the above issues.
v2:
(John Harrison)
- Fix typo in comment message
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214170500.28569-5-matthew.brost@intel.com
This is a revert of commits
d67739268c ("drm/i915/gt: Mark up the nested engine-pm timeline lock as irqsafe")
6c69a45445 ("drm/i915/gt: Mark context->active_count as protected by timeline->mutex")
6dcb85a0ad ("drm/i915: Hold irq-off for the entire fake lock period")
The existing code leads to a different behaviour depending on whether
lockdep is enabled or not. Any following lock that is acquired without
disabling interrupts (but needs to) will not be noticed by lockdep.
This it not just a lockdep annotation but is used but an actual mutex_t
that is properly used as a lock but in case of __timeline_mark_lock()
lockdep is only told that it is acquired but no lock has been acquired.
It appears that its purpose is just satisfy the lockdep_assert_held()
check in intel_context_mark_active(). The other problem with disabling
interrupts is that on PREEMPT_RT interrupts are also disabled which
leads to problems for instance later during memory allocation.
Add a CONTEXT_IS_PARKING bit to intel_engine_cs and set_bit/clear_bit it
instead of mutex_acquire/mutex_release. Use test_bit in the two
identified spots which relied on the lockdep annotation.
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/YbO8Ie1Nj7XcQPNQ@linutronix.de
On some platforms the hw has dropped support for 4K GTT pages when
dealing with LMEM, and due to the design of 64K GTT pages in the hw, we
can only mark the *entire* page-table as operating in 64K GTT mode,
since the enable bit is still on the pde, and not the pte. And since we
we still need to allow 4K GTT pages for SMEM objects, we can't have a
"normal" 4K page-table with scratch pointing to LMEM, since that's
undefined from the hw pov. The simplest solution is to just move the 64K
scratch page to SMEM on such platforms and call it a day, since that
should work for all configurations.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Thomas Hellstrom <thomas.hellstrom@linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211208141613.7251-4-ramalingam.c@intel.com
Certain functions within i915 uses macros that are defined for
specific architectures by the mmu, such as _PAGE_RW and _PAGE_PRESENT
(Some architectures don't even have these macros defined, like ARM64).
Instead of re-using bits defined for the CPU, we should use bits
defined for i915. This patch introduces two new 64 bit macros,
GEN8_PAGE_PRESENT and GEN8_PAGE_RW, to check for bits 0 and 1 and, to
replace all occurrences of _PAGE_RW and _PAGE_PRESENT within i915.
v2(Michael Cheng): Use GEN8_ instead of I915_
Signed-off-by: Michael Cheng <michael.cheng@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
[ Move defines together with other GEN8 defines ]
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211206215245.513677-2-michael.cheng@intel.com
With asynchronous migrations, the vma state may be several migrations
ahead of the state that matches the request we're capturing.
Address that by introducing an i915_vma_snapshot structure that
can be used to snapshot relevant state at request submission.
In order to make sure we access the correct memory, the snapshots take
references on relevant sg-tables and memory regions.
Also move the capture list allocation out of the fence signaling
critical path and use the CONFIG_DRM_I915_CAPTURE_ERROR define to
avoid compiling in members and functions used for error capture
when they're not used.
Finally, Introduce lockdep annotation.
v4:
- Break out the capture allocation mode change to a separate patch.
v5:
- Fix compilation error in the !CONFIG_DRM_I915_CAPTURE_ERROR case
(kernel test robot)
v6:
- Use #if IS_ENABLED() instead of #ifdef to match driver style.
- Move yet another change of allocation mode to the separate patch.
- Commit message rework due to patch reordering.
v7:
- Adjust for removal of region refcounting.
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211129202245.472043-1-thomas.hellstrom@linux.intel.com
In igt_request_rewind(), mock_context(i915, "A") is assigned to ctx[0]
and used in i915_gem_context_get_engine(). There is a dereference
of ctx[0] in i915_gem_context_get_engine(), which could lead to a NULL
pointer dereference on failure of mock_context(i915, "A") .
So as mock_context(i915, "B").
Although this bug is not serious for it belongs to testing code, it is
better to be fixed to avoid unexpected failure in testing.
Fix this bugs by adding checks about ctx[0] and ctx[1].
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_DRM_I915_SELFTEST=y show no new warnings,
and our static analyzer no longer warns about this code.
References: 591c0fb85d ("drm/i915: Exercise request cancellation using a mock selftest")
[tursulin: Replaced fixes with references to avoid.]
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211130141545.153899-1-zhou1615@umn.edu
With both integrated and discrete Intel GPUs in a system, the current
global check of intel_iommu_gfx_mapped, as done from intel_vtd_active()
may not be completely accurate.
In this patch we add i915 parameter to intel_vtd_active() in order to
prepare it for multiple GPUs and we also change the check away from Intel
specific intel_iommu_gfx_mapped (global exported by the Intel IOMMU
driver) to probing the presence of IOMMU on a specific device using
device_iommu_mapped().
This will return true both for IOMMU pass-through and address translation
modes which matches the current behaviour. If in the future we wanted to
distinguish between these two modes we could either use
iommu_get_domain_for_dev() and check for __IOMMU_DOMAIN_PAGING bit
indicating address translation, or ask for a new API to be exported from
the IOMMU core code.
v2:
* Check for dmar translation specifically, not just iommu domain. (Baolu)
v3:
* Go back to plain "any domain" check for now, rewrite commit message.
v4:
* Use device_iommu_mapped. (Robin, Baolu)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211126141424.493753-1-tvrtko.ursulin@linux.intel.com
Rather than stealing bits from i915_sw_fence function pointer use
separate fields for function pointer and flags. If using two different
fields, the 4 byte alignment for the i915_sw_fence function pointer can
also be dropped.
v2:
(CI)
- Set new function field rather than flags in __i915_sw_fence_init
v3:
(Tvrtko)
- Remove BUG_ON(!fence->flags) in reinit as that will now blow up
- Only define fence->flags if CONFIG_DRM_I915_SW_FENCE_CHECK_DAG is
defined
v4:
- Rebase, resend for CI
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211116194929.10211-1-matthew.brost@intel.com
Since the PMU callback runs in irq context, it synchronizes with gt
reset using the reset count. We could run into a case where the PMU
callback could read the reset count before it is updated. This has a
potential of corrupting the busyness stats.
In addition to the reset count, check if the reset bit is set before
capturing busyness.
In addition save the previous stats only if you intend to update them.
v2:
- The 2 reset counts captured in the PMU callback can end up being the
same if they were captured right after the count is incremented in the
reset flow. This can lead to a bad busyness state. Ensure that reset
is not in progress when the initial reset count is captured.
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211108211057.68783-1-umesh.nerlige.ramappa@intel.com
The gpu coredump typically takes place in a dma_fence signalling
critical path, and hence can't use GFP_KERNEL allocations, as that
means we might hit deadlocks under memory pressure. However
changing to __GFP_KSWAPD_RECLAIM which will be done in an upcoming
patch will instead mean a lower chance of the allocation succeeding.
In particular large contigous allocations like the coredump page
vector.
Remove the page vector in favor of a linked list of single pages.
Use the page lru list head as the list link, as the page owner is
allowed to do that.
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211108174547.979714-2-thomas.hellstrom@linux.intel.com
