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
In intel_context_do_pin_ww, when calling into the pre_pin hook(which is
passed the ww context) it could in theory return -EDEADLK(which is very
likely with debug kernels), once we start adding more ww locking in there,
like in the next patch. If so then we need to be mindful of having to
restart the do_pin at this point.
If this is the kernel_context, or some other early in-kernel context
where we have yet to setup the default_state, then we always inhibit the
context restore, and instead rely on the delayed active_release to set
the CONTEXT_VALID_BIT for us(if we even care), which should indicate
that we have context switched away, and that our newly saved context
state should now be valid. However, since we currently grab the active
reference before the potential ww dance, we can end up setting the
CONTEXT_VALID_BIT much too early, if we need to backoff, and then upon
re-trying the do_pin, we could potentially cause the hardware to
incorrectly load some garbage context state when later context switching
to that context, but at the very least this will trigger the
GEM_BUG_ON() in __engine_unpark. For now let's just move any ww dance
stuff prior to arming the active reference.
For normal user contexts this shouldn't be a concern, since we should
already have the default_state ready when initialising the lrc state,
and so there should be no concern with active_release somehow
prematurely setting the CONTEXT_VALID_BIT.
v2(Thomas):
- Also re-order the onion unwind
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211117142024.1043017-1-matthew.auld@intel.com
For some users of multi-lrc, e.g. split frame, it isn't safe to preempt
mid BB. To safely enable preemption at the BB boundary, a handshake
between parent and child is needed, syncing the set of BBs at the
beginning and end of each batch. This is implemented via custom
emit_bb_start & emit_fini_breadcrumb functions and enabled by default if
a context is configured by set parallel extension.
Lastly, this patch updates the process descriptor to the correct size as
the memory used in the handshake is directly after the process
descriptor.
v2:
(John Harrison)
- Fix a few comments wording
- Add struture for parent page layout
v3:
(John Harrison)
- A structure for sync semaphore
- Use offsetof to calc address
- Update commit message
v4:
(John Harrison)
- Fix typos in comment explaining memory map of scratch page
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/20211014172005.27155-20-matthew.brost@intel.com
Update context and full GPU reset to work with multi-lrc. The idea is
parent context tracks all the active requests inflight for itself and
its children. The parent context owns the reset replaying / canceling
requests as needed.
v2:
(John Harrison)
- Simply loop in find active request
- Add comments to find ative request / reset loop
v3:
(John Harrison)
- s/its'/its/g
- Fix comment when searching for active request
- Reorder if state in __guc_reset_context
v4:
(Kernel test robot)
- Delete unused is_multi_lrc function
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014172005.27155-15-matthew.brost@intel.com
Introduce context parent-child relationship. Once this relationship is
created all pinning / unpinning operations are directed to the parent
context. The parent context is responsible for pinning all of its
children and itself.
This is a precursor to the full GuC multi-lrc implementation but aligns
to how GuC mutli-lrc interface is defined - a single H2G is used
register / deregister all of the contexts simultaneously.
Subsequent patches in the series will implement the pinning / unpinning
operations for parent / child contexts.
v2:
(Daniel Vetter)
- Add kernel doc, add wrapper to access parent to ensure safety
v3:
(John Harrison)
- Fix comment explaing GEM_BUG_ON in to_parent()
- Make variable names generic (non-GuC specific)
v4:
(John Harrison)
- s/its'/its/g
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/20211014172005.27155-8-matthew.brost@intel.com
Taking a PM reference to prevent intel_gt_wait_for_idle from short
circuiting while any user context has scheduling enabled. Returning GT
idle when it is not can cause all sorts of issues throughout the stack.
v2:
(Daniel Vetter)
- Add might_lock annotations to pin / unpin function
v3:
(CI)
- Drop intel_engine_pm_might_put from unpin path as an async put is
used
v4:
(John Harrison)
- Make intel_engine_pm_might_get/put work with GuC virtual engines
- Update commit message
v5:
- Update commit message again
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/20211014172005.27155-4-matthew.brost@intel.com
Taking a PM reference to prevent intel_gt_wait_for_idle from short
circuiting while a deregister context H2G is in flight. To do this must
issue the deregister H2G from a worker as context can be destroyed from
an atomic context and taking GT PM ref blows up. Previously we took a
runtime PM from this atomic context which worked but will stop working
once runtime pm autosuspend in enabled.
So this patch is two fold, stop intel_gt_wait_for_idle from short
circuting and fix runtime pm autosuspend.
v2:
(John Harrison)
- Split structure changes out in different patch
(Tvrtko)
- Don't drop lock in deregister_destroyed_contexts
v3:
(John Harrison)
- Flush destroyed contexts before destroying context reg pool
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/20211014172005.27155-3-matthew.brost@intel.com
5.15-rc1 crashes with blank screen when booting up on two ThinkPads
using i915. Bisections converge convincingly, but arrive at different
and surprising "culprits", none of them the actual culprit.
netconsole (with init_netconsole() hacked to call i915_init() when
logging has started, instead of by module_init()) tells the story:
kernel BUG at drivers/gpu/drm/i915/i915_sw_fence.c:245!
with RSI: ffffffff814d408b pointing to sw_fence_dummy_notify().
I've been building with CONFIG_CC_OPTIMIZE_FOR_SIZE=y, and that
function needs to be 4-byte aligned.
v2:
(Jani Nikula)
- Change BUG_ON to WARN_ON
v3:
(Jani / Tvrtko)
- Short circuit __i915_sw_fence_init on WARN_ON
v4:
(Lucas)
- Break WARN_ON changes out in a different patch
Fixes: 62eaf0ae21 ("drm/i915/guc: Support request cancellation")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Matthew Brost <matthew.brost@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/20210922015039.26411-1-matthew.brost@intel.com
5.15-rc1 crashes with blank screen when booting up on two ThinkPads
using i915. Bisections converge convincingly, but arrive at different
and suprising "culprits", none of them the actual culprit.
netconsole (with init_netconsole() hacked to call i915_init() when
logging has started, instead of by module_init()) tells the story:
kernel BUG at drivers/gpu/drm/i915/i915_sw_fence.c:245!
with RSI: ffffffff814d408b pointing to sw_fence_dummy_notify().
I've been building with CONFIG_CC_OPTIMIZE_FOR_SIZE=y, and that
function needs to be 4-byte aligned.
Fixes: 62eaf0ae21 ("drm/i915/guc: Support request cancellation")
Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds GuC backend support for i915_request_cancel(), which in turn
makes CONFIG_DRM_I915_REQUEST_TIMEOUT work.
This implementation makes use of fence while there are likely simplier
options. A fence was chosen because of another feature coming soon
which requires a user to block on a context until scheduling is
disabled. In that case we return the fence to the user and the user can
wait on that fence.
v2:
(Daniele)
- A comment about locking the blocked incr / decr
- A comments about the use of the fence
- Update commit message explaining why fence
- Delete redundant check blocked count in unblock function
- Ring buffer implementation
- Comment about blocked in submission path
- Shorter rpm path
v3:
(Checkpatch)
- Fix typos in commit message
(Daniel)
- Rework to simplier locking structure in guc_context_block / unblock
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-26-matthew.brost@intel.com
We receive notification of an engine reset from GuC at its
completion. Meaning GuC has potentially cleared any HW state
we may have been interested in capturing. GuC resumes scheduling
on the engine post-reset, as the resets are meant to be transparent,
further muddling our error state.
There is ongoing work to define an API for a GuC debug state dump. The
suggestion for now is to manually disable FW initiated resets in cases
where debug state is needed.
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/20210727002348.97202-19-matthew.brost@intel.com
With GuC scheduling, it isn't safe to unpin a context while scheduling
is enabled for that context as the GuC may touch some of the pinned
state (e.g. LRC). To ensure scheduling isn't enabled when an unpin is
done, a call back is added to intel_context_unpin when pin count == 1
to disable scheduling for that context. When the response CTB is
received it is safe to do the final unpin.
Future patches may add a heuristic / delay to schedule the disable
call back to avoid thrashing on schedule enable / disable.
v2:
(John H)
- s/drm_dbg/drm_err
(Daneiel)
- Clean up sched state function
Cc: John Harrison <john.c.harrison@intel.com>
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/20210721215101.139794-9-matthew.brost@intel.com
Implement GuC context operations which includes GuC specific operations
alloc, pin, unpin, and destroy.
v2:
(Daniel Vetter)
- Use msleep_interruptible rather than cond_resched in busy loop
(Michal)
- Remove C++ style comment
v3:
(Matthew Brost)
- Drop GUC_ID_START
(John Harrison)
- Fix a bunch of typos
- Use drm_err rather than drm_dbg for G2H errors
(Daniele)
- Fix ;; typo
- Clean up sched state functions
- Add lockdep for guc_id functions
- Don't call __release_guc_id when guc_id is invalid
- Use MISSING_CASE
- Add comment in guc_context_pin
- Use shorter path to rpm
(Daniele / CI)
- Don't call release_guc_id on an invalid guc_id in destroy
v4:
(Daniel Vetter)
- Add FIXME comment
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
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/20210721215101.139794-7-matthew.brost@intel.com
This essentially reverts
commit 84a1074920
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed Jan 24 11:36:08 2018 +0000
drm/i915: Shrink the GEM kmem_caches upon idling
mm/vmscan.c:do_shrink_slab() is a thing, if there's an issue with it
then we need to fix that there, not hand-roll our own slab shrinking
code in i915.
Also when this was added there was only one other caller of
kmem_cache_shrink (added 2005 to the acpi code). Now there's a 2nd one
outside of i915 code in a kunit test, which seems legit since that
wants to very carefully control what's in the kmem_cache. This out of
a total of over 500 calls to kmem_cache_create. This alone should have
been warning sign enough that we're doing something silly.
Noticed while reviewing a patch set from Jason to fix up some issues
in our i915_init() and i915_exit() module load/cleanup code. Now that
i915_globals.c isn't any different than normal init/exit functions, we
should convert them over to one unified table and remove
i915_globals.[hc] entirely.
v2: Improve commit message (Jason)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Cc: David Airlie <airlied@linux.ie>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210721183229.4136488-1-daniel.vetter@ffwll.ch
Previously, we were storing the ring size in the ring pointer before it
was actually allocated. We would then guard setting the ring size on
checking for CONTEXT_ALLOC_BIT. This is error-prone at best and really
only saves us a few bytes on something that already burns at least 4K.
Instead, this patch adds a new ring_size field and makes everything use
that.
v2 (Daniel Vetter):
- Replace 512 * SZ_4K with SZ_2M
v2 (Jason Ekstrand):
- Rebase on top of page migration code
Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210708154835.528166-3-jason@jlekstrand.net
We use some of the lower bits of the retire function pointer for
potential flags, which is quite thorny, since the caller needs to
remember to give the function the correct alignment with
__i915_active_call, otherwise we might incorrectly unpack the pointer
and jump to some garbage address later. Instead of all this let's just
pass the flags along as a separate parameter.
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
References: ca419f407b ("drm/i915: Fix crash in auto_retire")
References: d8e44e4dd2 ("drm/i915/overlay: Fix active retire callback alignment")
References: fd5f262db1 ("drm/i915/selftests: Fix active retire callback alignment")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210504164136.96456-1-matthew.auld@intel.com
Allow a brief period for continued access to a dead intel_context by
deferring the release of the struct until after an RCU grace period.
As we are using a dedicated slab cache for the contexts, we can defer
the release of the slab pages via RCU, with the caveat that individual
structs may be reused from the freelist within an RCU grace period. To
handle that, we have to avoid clearing members of the zombie struct.
This is required for a later patch to handle locking around virtual
requests in the signaler, as those requests may want to move between
engines and be destroyed while we are holding b->irq_lock on a physical
engine.
v2: Drop mutex_reinit(), if we never mark the mutex as destroyed we
don't need to reset the debug code, at the loss of having the mutex
debug code spot us attempting to destroy a locked mutex.
v3: As the intended use will remain strongly referenced counted, with
very little inflight access across reuse, drop the ctor.
v4: Drop the unrequired change to remove the temporary reference around
dropping the active context, and add back some more missing ctor
operations.
v5: The ctor is back. Tvrtko spotted that ce->signal_lock [introduced
later] maybe accessed under RCU and so needs special care not to be
reinitialised.
v6: Don't mix SLAB_TYPESAFE_BY_RCU and RCU list iteration.
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/20201126140407.31952-3-chris@chris-wilson.co.uk
(cherry picked from commit 14d1eaf088)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
The hwsp_gtt object is used for sub-allocation and could therefore
be shared by many contexts causing unnecessary contention during
concurrent context pinning.
However since we're currently locking it only for pinning, it remains
resident until we unpin it, and therefore it's safe to drop the
lock early, allowing for concurrent thread access.
Signed-off-by: Thomas Hellström <thomas.hellstrom@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
GPU saves accumulated context runtime (in CS timestamp units) in PPHWSP
which will be useful for us in cases when we are not able to track context
busyness ourselves (like with GuC). Keep a copy of this in struct
intel_context from where it can be easily read even if the context is not
pinned.
v2:
(Chris)
* Do not store pphwsp address in intel_context.
* Log CS wrap-around.
* Simplify calculation by relying on integer wraparound.
v3:
* Include total/avg in traces and error state for debugging
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
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/20200216133620.394962-1-chris@chris-wilson.co.uk
