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With the removal of the internal wait-priority boosting, we can also
remove the selftest to ensure that those waits were being suppressed
from causing preemptions.
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/20200607222108.14401-4-chris@chris-wilson.co.uk
We have a test case to exercise resetting an engine while the other
engines are busy, all the TEST_SELF adds on top is that the target
engine also has background activity. In this case it is useful to first
test resetting the engine while there is background activity, as a
separate flag from exercising all others.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200607222108.14401-3-chris@chris-wilson.co.uk
In commit 5ba32c7be81e ("drm/i915/execlists: Always force a context
reload when rewinding RING_TAIL"), we placed the check for rewinding a
context on actually submitting the next request in that context. This
was so that we only had to check once, and could do so with precision
avoiding as many forced restores as possible. For example, to ensure
that we can resubmit the same request a couple of times, we include a
small wa_tail such that on the next submission, the ring->tail will
appear to move forwards when resubmitting the same request. This is very
common as it will happen for every lite-restore to fill the second port
after a context switch.
However, intel_ring_direction() is limited in precision to movements of
upto half the ring size. The consequence being that if we tried to
unwind many requests, we could exceed half the ring and flip the sense
of the direction, so missing a force restore. As no request can be
greater than half the ring (i.e. 2048 bytes in the smallest case), we
can check for rollback incrementally. As we check against the tail that
would be submitted, we do not lose any sensitivity and allow lite
restores for the simple case. We still need to double check upon
submitting the context, to allow for multiple preemptions and
resubmissions.
Fixes: 5ba32c7be81e ("drm/i915/execlists: Always force a context reload when rewinding RING_TAIL")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.4+
Reviewed-by: Bruce Chang <yu.bruce.chang@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200609151723.12971-1-chris@chris-wilson.co.uk
In some of our hangtests, we try to reset an active engine while it is
spinning inside the recursive spinner. However, we also try to flood the
engine with requests that preempt the hang, and so should disable the
preemption to be sure that we reset the right request.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200607222108.14401-2-chris@chris-wilson.co.uk
Sentinels are supposed to be last requests in the elsp queue, not the
only one, so adjust the assert accordingly.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200607222108.14401-1-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
We may choose not to submit for a number of reasons, yet not fill both
ELSP. In which case we must start timeslicing (there will be no ACK
event on which to hook the start) if the queue would benefit from the
currently active context being evicted.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200605122334.2798-2-chris@chris-wilson.co.uk
If we only submit the first port, leaving the second empty yet have
ready requests pending in the queue, use that to set the timeslicing
priority (i.e. the priority at which we will decided to enabling
timeslicing and evict the currently active context if the queue is of
equal priority after its quantum expired).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200605122334.2798-1-chris@chris-wilson.co.uk
Add engine->fw_domain/active to the pretty printer for debug dumps and
debugfs.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200605144705.31127-1-chris@chris-wilson.co.uk
Sometimes an engine might need to keep forcewake active while it is busy
submitting requests for a particular workaround. Track such nuisance
with engine->fw_domain.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Venkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200604153145.21068-1-chris@chris-wilson.co.uk
Use the plain msec_to_jiffies() rather than the _timeout variant so we
round down and do not add an extra jiffy to our interval. For example,
with timeslicing we do not want to err on the longer side as any
fairness depends on catching hogging contexts on the GPU. Bring on
CFS.
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/20200604135938.3975-1-chris@chris-wilson.co.uk
Set GS Timer to 224. Combine with Wa_1604555607 due to register FF_MODE2
not being able to be read.
V2: Math issue fixed
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Caz Yokoyama <caz.yokoyama@intel.com>
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Signed-off-by: Clint Taylor <clinton.a.taylor@intel.com>
Acked-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/20200603221150.14745-1-clinton.a.taylor@intel.com
We infrequently use the direct i915 backpointer from the i915_request,
so do we really need to waste the space in the struct for it? 8 bytes
from the most frequently allocated struct vs an 3 bytes and pointer
chasing in using rq->engine->i915?
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200602220953.21178-1-chris@chris-wilson.co.uk
If we injected an error (such as pretending the GuC firmware was
broken), then suppress the error message as it is expected and our CI
complains if it sees any *ERROR*.
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/20200603104657.25651-1-chris@chris-wilson.co.uk
For reasons that be, the HW only allows usersace to read its own
CTX_TIMESTAMP [context local HW runtime] on rcs. Make it available for
all by adding it to the whitelists.
v2: The change took effect from Cometlake.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200602154839.6902-1-chris@chris-wilson.co.uk
Cometlake is a small refresh of Coffeelake, but since we have found out a
difference in the plaforms, we need to identify them as separate platforms.
Since we previously took Coffeelake/Cometlake as identical, update all
IS_COFFEELAKE() to also include IS_COMETLAKE().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200602140541.5481-1-chris@chris-wilson.co.uk
As a timestamp will automatically update itself, it will not hold only
contexts we write into it, and will change from the baseline value
making us suspect that our writes are landing. As this confuses us and
we would need more careful treatment to detect invalid stores into the
timestamp, skip it when verifying the whitelists.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200602154839.6902-1-chris@chris-wilson.co.uk
Pull the routines for writing CS packets out of intel_ring_submission
into their own files. These are low level operations for building CS
instructions, rather than the logic for filling the global ring buffer
with requests, and we will want to reuse them outside of this context.
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/20200601072446.19548-2-chris@chris-wilson.co.uk
We may choose to only submit ELSP[0], even though we have sufficient
requests to fill the whole ELSP. Normally, we only start timeslicing if
we fill more than one port, but in this case we need to start
timeslicing for the queue that we choose not to submit.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200528205727.20309-1-chris@chris-wilson.co.uk
If the ring submission is stalled on an external request, nothing can be
submitted, not even the heartbeat in the kernel context. Since nothing
is running, resetting the engine/device does not unblock the system and
is pointless. We can see if the heartbeat is supposed to be running
before declaring foul.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200528074109.28235-2-chris@chris-wilson.co.uk
Across suspend/resume, we clear the entire GGTT and rebuild from
scratch. In particular, we want to only preserve the global entries for
use by the HW, and delay reinstating the local binds until required by
the user. This means that we can evict any local binds in the global GTT,
saving any time in preserving their state, as they will be rebound on
demand.
References: https://gitlab.freedesktop.org/drm/intel/-/issues/1947
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/20200528082427.21402-2-chris@chris-wilson.co.uk
We should be able to skip restoring LOCAL (user) binds within the GGTT on
resume and let them be restored upon demand. However, our consistency
checks demand that the bind flags match the node state, and we cannot
simply clear the flags, we need to evict as well. For now, make sure we
restore the bind flags exactly upon resume.
Fixes: 0109a16ef391 ("drm/i915/gt: Clear LOCAL_BIND from shared GGTT on resume")
Fixes: bf0840cdb304 ("drm/i915/gt: Stop cross-polluting PIN_GLOBAL with PIN_USER with no-ppgtt")
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/20200528150452.7880-1-chris@chris-wilson.co.uk
We have a I915_REQUEST_NOPREEMPT flag that we set when we must prevent
the HW from preempting during the course of this request. We need to
honour this flag and protect the HW even if we have a heartbeat request,
or other maximum priority barrier, pending. As such, restrict the
timeslicing check to avoid preempting into the topmost priority band,
leaving the unpreemptable requests in blissful peace running
uninterrupted on the HW.
v2: Set the I915_PRIORITY_BARRIER to be less than
I915_PRIORITY_UNPREEMPTABLE so that we never submit a request
(heartbeat or barrier) that can legitimately preempt the current
non-premptable request.
Fixes: 2a98f4e65bba ("drm/i915: add infrastructure to hold off preemption on a request")
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/20200527162418.24755-1-chris@chris-wilson.co.uk
gcc-9 gets confused by the code flow in check_dirty_whitelist:
drivers/gpu/drm/i915/gt/selftest_workarounds.c: In function 'check_dirty_whitelist':
drivers/gpu/drm/i915/gt/selftest_workarounds.c:492:17: error: 'rsvd' may be used uninitialized in this function [-Werror=maybe-uninitialized]
I could not figure out a good way to do this in a way that gcc
understands better, so initialize the variable to zero, as last
resort.
Fixes: aee20aaed887 ("drm/i915: Implement read-only support in whitelist selftest")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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/20200527140526.1458215-2-arnd@arndb.de
We only restore GLOBAL binds upon resume as we expect these to be pinned
for use by HW, whereas the LOCAL binds can be recreated on demand once
userspace is resumed. For the LOCAL bind to be recreated in the global
GTT (for old systems without ppgtt), we need to clear its presence flag
on deciding not to restore the mapping upon resume.
Fixes: bf0840cdb304 ("drm/i915/gt: Stop cross-polluting PIN_GLOBAL with PIN_USER with no-ppgtt")
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/20200526150739.26147-1-chris@chris-wilson.co.uk
If there are no internal levels and the user priority-shift is zero, we
can help the compiler eliminate some dead code:
Function old new delta
start_timeslice 169 154 -15
__execlists_submission_tasklet 4696 4659 -37
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200525075347.582-4-chris@chris-wilson.co.uk
Before we return control to the system, and letting it reuse all the
pages being accessed by HW, we must disable the HW. At the moment, we
dare not reset the GPU if it will clobber the display, but once we know
the display has been disabled, we can proceed with the reset as we
shutdown the module. We know the next user must reinitialise the HW for
their purpose.
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/489
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200525151459.12083-1-chris@chris-wilson.co.uk
Since the worker may rearm, we currently are only guaranteed to flush
the work if we cancel the timer. If the work was running at the time we
try and cancel it, we will wait for it to complete, but it may leave
items in the pool and requeue the work. If we rearrange the immediate
discard of the pool then cancel the work, we know that the work cannot
rearm and so our flush will be final.
<0> [314.146044] i915_mod-1321 2.... 299799443us : intel_gt_fini_buffer_pool: intel_gt_fini_buffer_pool:227 GEM_BUG_ON(!list_empty(&pool->cache_list[n]))
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1920
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200525141957.3061-1-chris@chris-wilson.co.uk
This assertion was removed in commit b412c63f1cba ("drm/i915/gt: Report
context-is-closed prior to pinning"), but accidentally restored by a
cherry-pick into drm-next and now has percolated back to
drm-intel-next-queued.
Fixes: 2e46a2a0b014 ("drm/i915: Use explicit flag to mark unreachable intel_context")
Fixes: 2b703bbda271 ("Merge drm/drm-next into drm-intel-next-queued")
References: b412c63f1cba ("drm/i915/gt: Report context-is-closed prior to pinning")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200520073048.2394034-1-chris@chris-wilson.co.uk
RKL uses the same GuC and HuC as TGL and should load the same firmwares.
Bspec: 50668
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504225227.464666-4-matthew.d.roper@intel.com
It was quite the oversight to only factor in the normal queue to decide
the timeslicing switch priority. By leaving out the next virtual request
from the priority decision, we would not timeslice the current engine if
there was an available virtual request.
Testcase: igt/gem_exec_balancer/sliced
Fixes: 3df2deed411e ("drm/i915/execlists: Enable timeslice on partial virtual engine dequeue")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200519132046.22443-3-chris@chris-wilson.co.uk
If we decide to timeslice out the current virtual request, we will
unsubmit it while it is still busy (ve->context.inflight == sibling[0]).
If the virtual tasklet and then the other sibling tasklets run before we
completely schedule out the active virtual request for the preemption,
those other tasklets will see that the virtul request is still inflight
on sibling[0] and leave it be. Therefore when we finally schedule-out
the virtual request and if we see that we have passed it back to the
virtual engine, reschedule the virtual tasklet so that it may be
resubmitted on any of the siblings.
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/20200519132046.22443-2-chris@chris-wilson.co.uk
Make sure that we can execute a virtual request on an already busy
engine, and conversely that we can execute a normal request if the
engines are already fully occupied by virtual requests.
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/20200519132046.22443-1-chris@chris-wilson.co.uk
When we look at i915_request_is_started() we must be careful in case we
are using a request that does not have the initial-breadcrumb and
instead the is-started is being compared against the end of the previous
request. This will make wait_for_submit() declare that a request has
been already submitted too early.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200519063123.20673-4-chris@chris-wilson.co.uk
Tvrtko spotted that some selftests were using 'break' not 'continue',
which will fail for discontiguous engine layouts such as on Icelake
(which may have vcs0 and vcs2).
Reported-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
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/20200518102911.3463-1-chris@chris-wilson.co.uk
The second try at staging the transfer of the breadcrumb. In part one,
we realised we could not simply move to the second engine as we were
only holding the breadcrumb lock on the first. So in commit 6c81e21a4742
("drm/i915/gt: Stage the transfer of the virtual breadcrumb"), we
removed it from the first engine and marked up this request to reattach
the signaling on the new engine. However, this failed to take into
account that we only attach the breadcrumb if the new request is added
at the start of the queue, which if we are transferring, it is because
we know there to be a request to be signaled (and hence we would not be
attached).
In this attempt, we try to transfer the completed requests to the
irq_worker on its rq->engine->breadcrumbs. This preserves the coupling
between the rq and its breadcrumbs, so that
i915_request_cancel_breadcrumb() does not attempt to manipulate the list
under the wrong lock.
v2: Code sharing is fun.
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1862
Fixes: 6c81e21a4742 ("drm/i915/gt: Stage the transfer of the virtual breadcrumb")
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/20200513074809.18194-1-chris@chris-wilson.co.uk
By providing the default values configured into the kernel via sysfs, it
is much more convenient for userspace to restore those sane defaults, or
at least know what are considered good baseline. This is useful, for
example, to cleanup after any failed userspace prior to commencing new
jobs.
/sys/class/drm/card0/engine/rcs0/
├── capabilities
├── class
├── .defaults
│ ├── heartbeat_interval_ms
│ ├── max_busywait_duration_ns
│ ├── preempt_timeout_ms
│ ├── stop_timeout_ms
│ └── timeslice_duration_ms
├── heartbeat_interval_ms
├── instance
├── known_capabilities
├── max_busywait_duration_ns
├── mmio_base
├── name
├── preempt_timeout_ms
├── stop_timeout_ms
└── timeslice_duration_ms
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200514062905.28668-1-chris@chris-wilson.co.uk
Now that we have fast timeslicing on semaphores, we no longer need to
prioritise none-semaphore work as we will yield any work blocked on a
semaphore to the next in the queue. Previously with no timeslicing,
blocking on the semaphore caused extremely bad scheduling with multiple
clients utilising multiple rings. Now, there is no impact and we can
remove the complication.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513173504.28322-1-chris@chris-wilson.co.uk
