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path: root/drivers/gpu/drm/i915/i915_active.h (follow)
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2020-04-06drm/i915: Allow asynchronous waits on the i915_active barriersChris Wilson1-0/+1
Allow the caller to also wait upon the barriers stored in i915_active. v2: Hook up i915_request_await_active(I915_ACTIVE_AWAIT_BARRIER) as well for completeness, and avoid the lazy GEM_BUG_ON()! v3: Pull flush_lazy_signals() under the active-ref protection as it too walks the rbtree and so we must be careful that we do not free it as we iterate. 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/20200406155840.1728-2-chris@chris-wilson.co.uk
2020-04-06drm/i915: Make exclusive awaits on i915_active optionalChris Wilson1-1/+2
Later use will require asynchronous waits on the active timelines, but will not utilize an async wait on the exclusive channel. Make the await on the exclusive fence explicit in the selection flags. 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/20200406155840.1728-1-chris@chris-wilson.co.uk
2020-03-30drm/i915: Wrap i915_active in a simple kreffed structChris Wilson1-0/+4
For conveniences of callers that just want to use an i915_active to track a wide array of concurrent timelines, wrap the base i915_active struct inside a kref. This i915_active will self-destruct after use. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200327112212.16046-2-chris@chris-wilson.co.uk
2020-03-30drm/i915: Allow for different modes of interruptible i915_active_waitChris Wilson1-1/+5
Allow some users the discretion to not immediately return on a normal signal. Hopefully, they will opt to use TASK_KILLABLE instead. 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/20200327112212.16046-1-chris@chris-wilson.co.uk
2020-03-11drm/i915: Extend i915_request_await_active to use all timelinesChris Wilson1-1/+7
Extend i915_request_await_active() to be able to asynchronously wait on all the tracked timelines simultaneously. 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/20200311092044.16353-1-chris@chris-wilson.co.uk
2020-01-30drm/i915: Use the async worker to avoid reclaim tainting the ggtt->mutexChris Wilson1-1/+2
On Braswell and Broxton (also known as Valleyview and Apollolake), we need to serialise updates of the GGTT using the big stop_machine() hammer. This has the side effect of appearing to lockdep as a possible reclaim (since it uses the cpuhp mutex and that is tainted by per-cpu allocations). However, we want to use vm->mutex (including ggtt->mutex) from within the shrinker and so must avoid such possible taints. For this purpose, we introduced the asynchronous vma binding and we can apply it to the PIN_GLOBAL so long as take care to add the necessary waits for the worker afterwards. Closes: https://gitlab.freedesktop.org/drm/intel/issues/211 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/20200130181710.2030251-3-chris@chris-wilson.co.uk
2020-01-27drm/i915/gt: Acquire ce->active before ce->pin_count/ce->pin_mutexChris Wilson1-0/+6
Similar to commit ac0e331a628b ("drm/i915: Tighten atomicity of i915_active_acquire vs i915_active_release") we have the same race of trying to pin the context underneath a mutex while allowing the decrement to be atomic outside of that mutex. This leads to the problem where two threads may simultaneously try to pin the context and the second not notice that they needed to repin the context. <2> [198.669621] kernel BUG at drivers/gpu/drm/i915/gt/intel_timeline.c:387! <4> [198.669703] invalid opcode: 0000 [#1] PREEMPT SMP PTI <4> [198.669712] CPU: 0 PID: 1246 Comm: gem_exec_create Tainted: G U W 5.5.0-rc6-CI-CI_DRM_7755+ #1 <4> [198.669723] Hardware name: /NUC7i5BNB, BIOS BNKBL357.86A.0054.2017.1025.1822 10/25/2017 <4> [198.669776] RIP: 0010:timeline_advance+0x7b/0xe0 [i915] <4> [198.669785] Code: 00 48 c7 c2 10 f1 46 a0 48 c7 c7 70 1b 32 a0 e8 bb dd e7 e0 bf 01 00 00 00 e8 d1 af e7 e0 31 f6 bf 09 00 00 00 e8 35 ef d8 e0 <0f> 0b 48 c7 c1 48 fa 49 a0 ba 84 01 00 00 48 c7 c6 10 f1 46 a0 48 <4> [198.669803] RSP: 0018:ffffc900004c3a38 EFLAGS: 00010296 <4> [198.669810] RAX: ffff888270b35140 RBX: ffff88826f32ee00 RCX: 0000000000000006 <4> [198.669818] RDX: 00000000000017c5 RSI: 0000000000000000 RDI: 0000000000000009 <4> [198.669826] RBP: ffffc900004c3a64 R08: 0000000000000000 R09: 0000000000000000 <4> [198.669834] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88826f9b5980 <4> [198.669841] R13: 0000000000000cc0 R14: ffffc900004c3dc0 R15: ffff888253610068 <4> [198.669849] FS: 00007f63e663fe40(0000) GS:ffff888276c00000(0000) knlGS:0000000000000000 <4> [198.669857] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [198.669864] CR2: 00007f171f8e39a8 CR3: 000000026b1f6005 CR4: 00000000003606f0 <4> [198.669872] Call Trace: <4> [198.669924] intel_timeline_get_seqno+0x12/0x40 [i915] <4> [198.669977] __i915_request_create+0x76/0x5a0 [i915] <4> [198.670024] i915_request_create+0x86/0x1c0 [i915] <4> [198.670068] i915_gem_do_execbuffer+0xbf2/0x2500 [i915] <4> [198.670082] ? __lock_acquire+0x460/0x15d0 <4> [198.670128] i915_gem_execbuffer2_ioctl+0x11f/0x470 [i915] <4> [198.670171] ? i915_gem_execbuffer_ioctl+0x300/0x300 [i915] <4> [198.670181] drm_ioctl_kernel+0xa7/0xf0 <4> [198.670188] drm_ioctl+0x2e1/0x390 <4> [198.670233] ? i915_gem_execbuffer_ioctl+0x300/0x300 [i915] Fixes: 841350223816 ("drm/i915/gt: Drop mutex serialisation between context pin/unpin") References: ac0e331a628b ("drm/i915: Tighten atomicity of i915_active_acquire vs i915_active_release") 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/20200127152829.2842149-1-chris@chris-wilson.co.uk
2019-12-02drm/i915: Specialise i915_active.work lock classesChris Wilson1-3/+7
Similar to for i915_active.mutex, we require each class of i915_active to have distinct lockdep chains as some, but by no means all, i915_active are used within the shrinker and so have much more severe usage constraints. By using a lockclass local to i915_active_init() all i915_active workers have the same lock class, and we may generate false positives when waiting for the i915_active. If we push the lockclass into the caller, each class of i915_active will have distinct lockdep chains. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191202140133.2444217-1-chris@chris-wilson.co.uk
2019-11-27drm/i915: Serialise i915_active_fence_set() with itselfChris Wilson1-15/+2
The expected downside to commit 58b4c1a07ada ("drm/i915: Reduce nested prepare_remote_context() to a trylock") was that it would need to return -EAGAIN to userspace in order to resolve potential mutex inversion. Such an unsightly round trip is unnecessary if we could atomically insert a barrier into the i915_active_fence, so make it happen. Currently, we use the timeline->mutex (or some other named outer lock) to order insertion into the i915_active_fence (and so individual nodes of i915_active). Inside __i915_active_fence_set, we only need then serialise with the interrupt handler in order to claim the timeline for ourselves. However, if we remove the outer lock, we need to ensure the order is intact between not only multiple threads trying to insert themselves into the timeline, but also with the interrupt handler completing the previous occupant. We use xchg() on insert so that we have an ordered sequence of insertions (and each caller knows the previous fence on which to wait, preserving the chain of all fences in the timeline), but we then have to cmpxchg() in the interrupt handler to avoid overwriting the new occupant. The only nasty side-effect is having to temporarily strip off the RCU-annotations to apply the atomic operations, otherwise the rules are much more conventional! Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112402 Fixes: 58b4c1a07ada ("drm/i915: Reduce nested prepare_remote_context() to a trylock") 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/20191127134527.3438410-1-chris@chris-wilson.co.uk
2019-11-02drm/i915/selftests: Flush all active callbacksChris Wilson1-0/+1
Flushing the outer i915_active is not enough, as we need the barrier to be applied across all the active dma_fence callbacks. So we must serialise with each outstanding fence. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112096 References: f79520bb3337 ("drm/i915/selftests: Synchronize checking active status with retirement") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Acked-by: Andi Shyti <andi.shyti@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191101181022.25633-1-chris@chris-wilson.co.uk
2019-10-31drm/i915/selftests: Pretty print the i915_activeChris Wilson1-0/+2
If the idle_pulse fails to flush the i915_active, dump the tree to see if that has any clues. 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/20191031101116.19894-1-chris@chris-wilson.co.uk
2019-10-04drm/i915: Coordinate i915_active with its own mutexChris Wilson1-261/+58
Forgo the struct_mutex serialisation for i915_active, and interpose its own mutex handling for active/retire. This is a multi-layered sleight-of-hand. First, we had to ensure that no active/retire callbacks accidentally inverted the mutex ordering rules, nor assumed that they were themselves serialised by struct_mutex. More challenging though, is the rule over updating elements of the active rbtree. Instead of the whole i915_active now being serialised by struct_mutex, allocations/rotations of the tree are serialised by the i915_active.mutex and individual nodes are serialised by the caller using the i915_timeline.mutex (we need to use nested spinlocks to interact with the dma_fence callback lists). The pain point here is that instead of a single mutex around execbuf, we now have to take a mutex for active tracker (one for each vma, context, etc) and a couple of spinlocks for each fence update. The improvement in fine grained locking allowing for multiple concurrent clients (eventually!) should be worth it in typical loads. v2: Add some comments that barely elucidate anything :( 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/20191004134015.13204-6-chris@chris-wilson.co.uk
2019-10-04drm/i915: Pull i915_vma_pin under the vm->mutexChris Wilson1-0/+7
Replace the struct_mutex requirement for pinning the i915_vma with the local vm->mutex instead. Note that the vm->mutex is tainted by the shrinker (we require unbinding from inside fs-reclaim) and so we cannot allocate while holding that mutex. Instead we have to preallocate workers to do allocate and apply the PTE updates after we have we reserved their slot in the drm_mm (using fences to order the PTE writes with the GPU work and with later unbind). In adding the asynchronous vma binding, one subtle requirement is to avoid coupling the binding fence into the backing object->resv. That is the asynchronous binding only applies to the vma timeline itself and not to the pages as that is a more global timeline (the binding of one vma does not need to be ordered with another vma, nor does the implicit GEM fencing depend on a vma, only on writes to the backing store). Keeping the vma binding distinct from the backing store timelines is verified by a number of async gem_exec_fence and gem_exec_schedule tests. The way we do this is quite simple, we keep the fence for the vma binding separate and only wait on it as required, and never add it to the obj->resv itself. Another consequence in reducing the locking around the vma is the destruction of the vma is no longer globally serialised by struct_mutex. A natural solution would be to add a kref to i915_vma, but that requires decoupling the reference cycles, possibly by introducing a new i915_mm_pages object that is own by both obj->mm and vma->pages. However, we have not taken that route due to the overshadowing lmem/ttm discussions, and instead play a series of complicated games with trylocks to (hopefully) ensure that only one destruction path is called! v2: Add some commentary, and some helpers to reduce patch churn. 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/20191004134015.13204-4-chris@chris-wilson.co.uk
2019-09-20drm/i915: Mark i915_request.timeline as a volatile, rcu pointerChris Wilson1-0/+6
The request->timeline is only valid until the request is retired (i.e. before it is completed). Upon retiring the request, the context may be unpinned and freed, and along with it the timeline may be freed. We therefore need to be very careful when chasing rq->timeline that the pointer does not disappear beneath us. The vast majority of users are in a protected context, either during request construction or retirement, where the timeline->mutex is held and the timeline cannot disappear. It is those few off the beaten path (where we access a second timeline) that need extra scrutiny -- to be added in the next patch after first adding the warnings about dangerous access. One complication, where we cannot use the timeline->mutex itself, is during request submission onto hardware (under spinlocks). Here, we want to check on the timeline to finalize the breadcrumb, and so we need to impose a second rule to ensure that the request->timeline is indeed valid. As we are submitting the request, it's context and timeline must be pinned, as it will be used by the hardware. Since it is pinned, we know the request->timeline must still be valid, and we cannot submit the idle barrier until after we release the engine->active.lock, ergo while submitting and holding that spinlock, a second thread cannot release the timeline. v2: Don't be lazy inside selftests; hold the timeline->mutex for as long as we need it, and tidy up acquiring the timeline with a bit of refactoring (i915_active_add_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/20190919111912.21631-1-chris@chris-wilson.co.uk
2019-08-16drm/i915: Markup expected timeline locks for i915_activeChris Wilson1-2/+10
As every i915_active_request should be serialised by a dedicated lock, i915_active consists of a tree of locks; one for each node. Markup up the i915_active_request with what lock is supposed to be guarding it so that we can verify that the serialised updated are indeed serialised. 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/20190816121000.8507-2-chris@chris-wilson.co.uk
2019-08-12drm/i915/overlay: Switch to using i915_active trackingChris Wilson1-19/+0
Remove the raw i915_active_request tracking in favour of the higher level i915_active tracking for the sole purpose of making the lockless transition easier in later patches. 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/20190812174804.26180-2-chris@chris-wilson.co.uk
2019-08-02drm/i915: Allow sharing the idle-barrier from other kernel requestsChris Wilson1-1/+1
By placing our idle-barriers in the i915_active fence tree, we expose those for reuse by other components that are issuing requests along the kernel_context. Reusing the proto-barrier active_node is perfectly fine as the new request implies a context-switch, and so an opportune point to run the idle-barrier. However, the proto-barrier is not equivalent to a normal active_node and care must be taken to avoid dereferencing the ERR_PTR used as its request marker. v2: Comment the more egregious cheek v3: A glossary! Reported-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Fixes: ce476c80b8bf ("drm/i915: Keep contexts pinned until after the next kernel context switch") Fixes: a9877da2d629 ("drm/i915/oa: Reconfigure contexts on the fly") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190802100015.1281-1-chris@chris-wilson.co.uk
2019-07-26drm/i915: Capture vma contents outside of spinlockChris Wilson1-0/+3
Currently we use the engine->active.lock to ensure that the request is not retired as we capture the data. However, we only need to ensure that the vma are not removed prior to use acquiring their contents, and since we have already relinquished our stop-machine protection, we assume that the user will not be overwriting the contents before we are able to record them. In order to capture the vma outside of the spinlock, we acquire a reference and mark the vma as active to prevent it from being unbound. However, since it is tricky allocate an entry in the fence tree (doing so would require taking a mutex) while inside the engine spinlock, we use an atomic bit and special case the handling for i915_active_wait. The core benefit is that we can use some non-atomic methods for mapping the device pages, we can remove the slow compression phase out of atomic context (i.e. stop antagonising the nmi-watchdog), and no we longer need large reserves of atomic pages. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111215 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190725223843.8971-1-chris@chris-wilson.co.uk
2019-06-21drm/i915: Provide an i915_active.acquire callbackChris Wilson1-12/+13
If we introduce a callback for i915_active that is only called the first time we use the i915_active and is symmetrically paired with the i915_active.retire callback, we can replace the open-coded and non-atomic implementations -- which will be very fragile (i.e. broken) upon removing the struct_mutex serialisation. 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/20190621183801.23252-4-chris@chris-wilson.co.uk
2019-06-19drm/i915: Stop passing I915_WAIT_LOCKED to i915_request_wait()Chris Wilson1-1/+1
Since commit eb8d0f5af4ec ("drm/i915: Remove GPU reset dependence on struct_mutex"), the I915_WAIT_LOCKED flags passed to i915_request_wait() has been defunct. Now go ahead and remove it from all callers. References: eb8d0f5af4ec ("drm/i915: Remove GPU reset dependence on struct_mutex") 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/20190618074153.16055-3-chris@chris-wilson.co.uk
2019-06-14drm/i915: Keep contexts pinned until after the next kernel context switchChris Wilson1-0/+5
We need to keep the context image pinned in memory until after the GPU has finished writing into it. Since it continues to write as we signal the final breadcrumb, we need to keep it pinned until the request after it is complete. Currently we know the order in which requests execute on each engine, and so to remove that presumption we need to identify a request/context-switch we know must occur after our completion. Any request queued after the signal must imply a context switch, for simplicity we use a fresh request from the kernel context. The sequence of operations for keeping the context pinned until saved is: - On context activation, we preallocate a node for each physical engine the context may operate on. This is to avoid allocations during unpinning, which may be from inside FS_RECLAIM context (aka the shrinker) - On context deactivation on retirement of the last active request (which is before we know the context has been saved), we add the preallocated node onto a barrier list on each engine - On engine idling, we emit a switch to kernel context. When this switch completes, we know that all previous contexts must have been saved, and so on retiring this request we can finally unpin all the contexts that were marked as deactivated prior to the switch. We can enhance this in future by flushing all the idle contexts on a regular heartbeat pulse of a switch to kernel context, which will also be used to check for hung engines. v2: intel_context_active_acquire/_release Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190614164606.15633-1-chris@chris-wilson.co.uk
2019-03-08drm/i915: Remove has-kernel-contextChris Wilson1-13/+0
We can no longer assume execution ordering, and in particular we cannot assume which context will execute last. One side-effect of this is that we cannot determine if the kernel-context is resident on the GPU, so remove the routines that claimed to do so. 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/20190308093657.8640-4-chris@chris-wilson.co.uk
2019-03-06drm/i915: Use i915_global_register()Chris Wilson1-4/+0
Rather than manually add every new global into each hook, use i915_global_register() function and keep a list of registered globals to invoke instead. However, I haven't found a way for random drivers to add an .init table to avoid having to manually add ourselves to i915_globals_init() each time. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20190305213830.18094-1-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
2019-02-28drm/i915: Make request allocation caches globalChris Wilson1-0/+1
As kmem_caches share the same properties (size, allocation/free behaviour) for all potential devices, we can use global caches. While this potential has worse fragmentation behaviour (one can argue that different devices would have different activity lifetimes, but you can also argue that activity is temporal across the system) it is the default behaviour of the system at large to amalgamate matching caches. The benefit for us is much reduced pointer dancing along the frequent allocation paths. v2: Defer shrinking until after a global grace period for futureproofing multiple consumers of the slab caches, similar to the current strategy for avoiding shrinking too early. 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/20190228102035.5857-1-chris@chris-wilson.co.uk
2019-02-05drm/i915: Pull i915_gem_active into the i915_active familyChris Wilson1-0/+349
Looking forward, we need to break the struct_mutex dependency on i915_gem_active. In the meantime, external use of i915_gem_active is quite beguiling, little do new users suspect that it implies a barrier as each request it tracks must be ordered wrt the previous one. As one of many, it can be used to track activity across multiple timelines, a shared fence, which fits our unordered request submission much better. We need to steer external users away from the singular, exclusive fence imposed by i915_gem_active to i915_active instead. As part of that process, we move i915_gem_active out of i915_request.c into i915_active.c to start separating the two concepts, and rename it to i915_active_request (both to tie it to the concept of tracking just one request, and to give it a longer, less appealing name). 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/20190205130005.2807-5-chris@chris-wilson.co.uk
2019-02-05drm/i915: Allocate active tracking nodes from a slabcacheChris Wilson1-0/+3
Wrap the active tracking for a GPU references in a slabcache for faster allocations, and hopefully better fragmentation reduction. v3: Nothing device specific left, it's just a slabcache that we can make global. v4: Include i915_active.h and don't put the initfunc under DEBUG_GEM 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/20190205130005.2807-4-chris@chris-wilson.co.uk
2019-02-05drm/i915: Release the active tracker tree upon idlingChris Wilson1-0/+4
As soon as we detect that the active tracker is idle and we prepare to call the retire callback, release the storage for our tree of per-timeline nodes. We expect these to be infrequently used and quick to allocate, so there is little benefit in keeping the tree cached and we would prefer to return the pages back to the system in a timely fashion. This also means that when we finalize the struct as a whole, we know as the activity tracker must be idle, the tree has already been released. Indeed we can reduce i915_active_fini() just to the assertions that there is nothing to do. 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/20190205130005.2807-3-chris@chris-wilson.co.uk
2019-02-05drm/i915: Generalise GPU activity trackingChris Wilson1-0/+69
We currently track GPU memory usage inside VMA, such that we never release memory used by the GPU until after it has finished accessing it. However, we may want to track other resources aside from VMA, or we may want to split a VMA into multiple independent regions and track each separately. For this purpose, generalise our request tracking (akin to struct reservation_object) so that we can embed it into other objects. v2: Tweak error handling during selftest setup. 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/20190205130005.2807-2-chris@chris-wilson.co.uk