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* drm/i915: Use execlists_num_ports instead of size of arrayMika Kuoppala2017-10-101-1/+1
| | | | | | | | | | | | | | There is function to tell how many ports we have, so use it. We still have direct relationship with array size and port count, so no harm was done. Fixes: 76e70087d360 ("drm/i915: Make execlist port count variable") Cc: Mika Kuoppala <mika.kuoppala@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171010114857.13108-1-mika.kuoppala@intel.com
* drm/i915/execlists: Add a comment for the extra MI_ARB_ENABLEChris Wilson2017-10-061-1/+17
| | | | | | | | | | | | | | | | Michel Thierry noticed that we were applying WaDisableCtxRestoreArbitration even to gen9, which does not require the w/a. The rationale is that we need to enable MI arbitration for execlists to work, and to be safe we do that before every batch (in addition to every context switch into the batch). Since this is not clear from the single line comment suggesting the MI_ARB_ENABLE is solely for the w/a, add a little more detail. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michel Thierry <michel.thierry@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Michał Winiarski <michal.winiarski@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171005191005.13462-1-chris@chris-wilson.co.uk Reviewed-by: Michel Thierry <michel.thierry@intel.com>
* drm/i915/execlists: Preemption!Chris Wilson2017-10-041-31/+126
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we write to ELSP, it triggers a context preemption at the earliest arbitration point (3DPRIMITIVE, some PIPECONTROLs, a few other operations and the explicit MI_ARB_CHECK). If this is to the same context, it triggers a LITE_RESTORE where the RING_TAIL is merely updated (used currently to chain requests from the same context together, avoiding bubbles). However, if it is to a different context, a full context-switch is performed and it will start to execute the new context saving the image of the old for later execution. Previously we avoided preemption by only submitting a new context when the old was idle. But now we wish embrace it, and if the new request has a higher priority than the currently executing request, we write to the ELSP regardless, thus triggering preemption, but we tell the GPU to switch to our special preemption context (not the target). In the context-switch interrupt handler, we know that the previous contexts have finished execution and so can unwind all the incomplete requests and compute the new highest priority request to execute. It would be feasible to avoid the switch-to-idle intermediate by programming the ELSP with the target context. The difficulty is in tracking which request that should be whilst maintaining the dependency change, the error comes in with coalesced requests. As we only track the most recent request and its priority, we may run into the issue of being tricked in preempting a high priority request that was followed by a low priority request from the same context (e.g. for PI); worse still that earlier request may be our own dependency and the order then broken by preemption. By injecting the switch-to-idle and then recomputing the priority queue, we avoid the issue with tracking in-flight coalesced requests. Having tried the preempt-to-busy approach, and failed to find a way around the coalesced priority issue, Michal's original proposal to inject an idle context (based on handling GuC preemption) succeeds. The current heuristic for deciding when to preempt are only if the new request is of higher priority, and has the privileged priority of greater than 0. Note that the scheduler remains unfair! v2: Disable for gen8 (bdw/bsw) as we need additional w/a for GPGPU. Since, the feature is now conditional and not always available when we have a scheduler, make it known via the HAS_SCHEDULER GETPARAM (now a capability mask). v3: Stylistic tweaks. v4: Appease Joonas with a snippet of kerneldoc, only to fuel to fire of the preempt vs preempting debate. Suggested-by: Michal Winiarski <michal.winiarski@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michal Winiarski <michal.winiarski@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Cc: Ben Widawsky <benjamin.widawsky@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171003203453.15692-8-chris@chris-wilson.co.uk
* drm/i915/execlists: Keep request->priority for its lifetimeChris Wilson2017-10-041-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | With preemption, we will want to "unsubmit" a request, taking it back from the hw and returning it to the priority sorted execution list. In order to know where to insert it into that list, we need to remember its adjust priority (which may change even as it was being executed). This also affects reset for execlists as we are now unsubmitting the requests following the reset (rather than directly writing the ELSP for the inflight contexts). This turns reset into an accidental preemption point, as after the reset we may choose a different pair of contexts to submit to hw. GuC is not updated as this series doesn't add preemption to the GuC submission, and so it can keep benefiting from the early pruning of the DFS inside execlists_schedule() for a little longer. We also need to find a way of reducing the cost of that DFS... v2: Include priority in error-state Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michał Winiarski <michal.winiarski@intel.com> Reviewed-by: Michał Winiarski <michal.winiarski@intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171003203453.15692-6-chris@chris-wilson.co.uk
* drm/i915/execlists: Move bdw GPGPU w/a to emit_bbChris Wilson2017-10-041-20/+4
| | | | | | | | | Move the re-enabling of MI arbitration from a per-bb w/a buffer to the emission of the batch buffer itself. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171003203453.15692-5-chris@chris-wilson.co.uk
* drm/i915/execlists: Distinguish the incomplete context notifiesChris Wilson2017-10-041-1/+1
| | | | | | | | | | | | | | | | | | Let the listener know that the context we just scheduled out was not complete, and will be scheduled back in at a later point. v2: Handle CONTEXT_STATUS_PREEMPTED in gvt by aliasing it to CONTEXT_STATUS_OUT for the moment, gvt can expand upon the difference later. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: "Zhenyu Wang" <zhenyuw@linux.intel.com> Cc: "Wang, Zhi A" <zhi.a.wang@intel.com> Cc: Michał Winiarski <michal.winiarski@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171003203453.15692-3-chris@chris-wilson.co.uk
* drm/i915: Remove use_mmio_flip modparm, v2.Maarten Lankhorst2017-10-041-2/+1
| | | | | | | | | | | | | | This has been unused since commit afa8ce5b3080 ("drm/i915: Nuke legacy flip queueing code"). Changes since v1: - Rebase on top of all the changes to modparams. Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> \o/-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171004094416.31306-1-maarten.lankhorst@linux.intel.com
* drm/i915/execlists: Cache the last priolist lookupMichał Winiarski2017-09-291-7/+13
| | | | | | | | | | | | Avoid the repeated rbtree lookup for each request as we unwind them by tracking the last priolist. v2: Fix up my unhelpful suggestion of using default_priolist. Signed-off-by: Michał Winiarski <michal.winiarski@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170928193910.17988-4-chris@chris-wilson.co.uk
* drm/i915: Give the invalid priority a magic nameChris Wilson2017-09-291-1/+3
| | | | | | | | | | | | We use INT_MIN to denote the priority of a request that has not been submitted to the scheduler; we treat INT_MIN as an invalid priority and initialise the request to it. Give the value a name so it stands out. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170928193910.17988-3-chris@chris-wilson.co.uk Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com
* drm/i915/execlists: Move request unwinding to a separate functionChris Wilson2017-09-291-20/+34
| | | | | | | | | | | In the future, we will want to unwind requests following a preemption point. This requires the same steps as for unwinding upon a reset, so extract the existing code to a separate function for later use. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170928193910.17988-2-chris@chris-wilson.co.uk
* drm/i915/execlists: Notify context-out for lost requestsChris Wilson2017-09-271-1/+5
| | | | | | | | | | | | | | | | | When cancelling requests, also send the notification to any listeners (gvt) that the request is no longer scheduled on hw. They may require to keep the in/out exactly balanced, and so the reuse after the reset may confuse the listener. Fixes: 221ab9719bf3 ("drm/i915/execlists: Unwind incomplete requests on resets") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: "Zhenyu Wang" <zhenyuw@linux.intel.com> Cc: "Wang, Zhi A" <zhi.a.wang@intel.com> Cc: Michał Winiarski <michal.winiarski@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170926101720.9479-1-chris@chris-wilson.co.uk Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
* drm/i915/execlists: Microoptimise execlists_cancel_port_request()Chris Wilson2017-09-251-7/+10
| | | | | | | | | Just rearrange the code slightly to trim the number of iterations required. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170925124929.16974-1-chris@chris-wilson.co.uk Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
* drm/i915/lrc: Skip no-op per-bb buffer on gen9Chris Wilson2017-09-251-8/+1
| | | | | | | | | | | | | | Since we inherited the context image setup from gen8 which needed a per-bb workaround (for GPGPU), we are submitting an empty per-bb buffer on gen9. Now that we can skip adding the buffer to the context image, remove the dangling per-bb. This slightly improves execution latency, most notably on an idle engine. References: https://bugs.freedesktop.org/show_bug.cgi?id=87725 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170921135444.27330-2-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
* drm/i915/lrc: Only enable per-context and per-bb buffers if setChris Wilson2017-09-251-5/+10
| | | | | | | | | | | | | The per-context and per-batch workaround buffers are optional, yet we tell the GPU to execute them even if they contain no instructions. Doing so incurs the dispatch latency, which we can avoid if we don't ask the GPU to execute the no-op buffers. Allow ourselves to skip setup of empty buffer, and then to only enable non-empty buffers in the context image. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170921135444.27330-1-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
* drm/i915: Make execlist port count variableMika Kuoppala2017-09-251-2/+4
| | | | | | | | | | | | | | As we emulate execlists on top of the GuC workqueue, it is not restricted to just 2 ports and we can increase that number arbitrarily to trade-off queue depth (i.e. scheduling latency) against pipeline bubbles. v2: rebase. better commit msg (Chris) v3: rebase Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170922124307.10914-5-mika.kuoppala@intel.com
* drm/i915: Add execlist_port_completeMika Kuoppala2017-09-251-11/+11
| | | | | | | | | | | | | When first execlist entry is processed, we move the port (contents). Introduce function for this as execlist and guc use this common operation. v2: rebase. s/GEM_DEBUG_BUG/GEM_BUG (Chris) v3: rebase Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170922124307.10914-4-mika.kuoppala@intel.com
* drm/i915: Wrap port cancellation into a functionMika Kuoppala2017-09-251-11/+14
| | | | | | | | | | | | | | | | On reset and wedged path, we want to release the requests that are tied to ports and then mark the ports to be unset. Introduce a function for this. v2: rebase v3: drop local, keep GEM_BUG_ON (Michał, Chris) v4: rebase Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Michał Winiarski <michal.winiarski@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170922124307.10914-3-mika.kuoppala@intel.com
* drm/i915: Move execlist initialization into intel_engine_cs.cMika Kuoppala2017-09-251-19/+0
| | | | | | | | | | | | Move execlist init into a common engine setup. As it is common to both guc and hw execlists. v2: rebase with csb changes v3: rebase Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170922124307.10914-2-mika.kuoppala@intel.com
* drm/i915: Make own struct for execlist itemsMika Kuoppala2017-09-251-47/+53
| | | | | | | | | | | | | | | | | | | | Engine's execlist related items have been increasing to a point where a separate struct is warranted. Carve execlist specific items to a dedicated struct to add clarity. v2: add kerneldoc and fix whitespace (Joonas, Chris) v3: csb_mmio changes, rebase v4: s/\b(el|execlist)\b/execlists/ (Joonas) Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Michał Winiarski <michal.winiarski@intel.com> (v3) Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v3) Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170922124307.10914-1-mika.kuoppala@intel.com
* drm/i915: Rename global i915 to i915_modparamsMichal Wajdeczko2017-09-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Our global struct with params is named exactly the same way as new preferred name for the drm_i915_private function parameter. To avoid such name reuse lets use different name for the global. v5: pure rename v6: fix Credits-to: Coccinelle @@ identifier n; @@ ( - i915.n + i915_modparams.n ) Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Ville Syrjala <ville.syrjala@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170919193846.38060-1-michal.wajdeczko@intel.com
* drm/i915/guc: Submit GuC workitems containing coalesced requestsMichał Winiarski2017-09-181-22/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | To create an upper bound on number of GuC workitems, we need to change the way that requests are being submitted. Rather than submitting each request as an individual workitem, we can do coalescing in a similar way we're handlig execlist submission ports. We also need to stop pretending that we're doing "lite-restore" in GuC submission (we would create a workitem each time we hit this condition). This allows us to completely remove the reservation, replacing it with a compile time check. v2: Also coalesce when replaying on reset (Daniele) v3: Consistent wq_resv - per-request (Daniele) v4: Squash removing wq_resv v5: Reflect i915_guc_submit argument changes in doc v6: Rebase on top of execlists reset/restart fix (Chris,Michał) References: https://bugs.freedesktop.org/show_bug.cgi?id=101873 Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Jeff McGee <jeff.mcgee@intel.com> Cc: Michal Wajdeczko <michal.wajdeczko@intel.com> Cc: Oscar Mateo <oscar.mateo@intel.com> Signed-off-by: Michał Winiarski <michal.winiarski@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170914083216.10192-2-michal.winiarski@intel.com Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
* drm/i915/execlists: Unwind incomplete requests on resetsChris Wilson2017-09-181-35/+26
| | | | | | | | | | | | | | | | | | | | | | | Given the mechanism to unwind and replay requests (designed to support preemption), we have an alternative to the current method of resubmitting the ELSP upon reset. Resubmitting ELSP turns out to be more complicated than expected, due to having to handle lost context-switch interrupts and so guessing what ELSP we need to resubmit later. Instead, by unwinding the requests and clearing the ELSP tracking entirely, we can then just dequeue the first pair of ready requests after resetting, using the normal submission procedure. Currently, the unwound requests have maximum priority and so are guaranteed to be resubmitted upon resume. If we are lucky, we may be able to coalesce a new request on top! Suggested-by: Michał Winiarski <michal.winiarski@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michał Winiarski <michal.winiarski@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170916204414.32762-4-chris@chris-wilson.co.uk Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
* drm/i915/execlists: Split insert_request()Chris Wilson2017-09-181-16/+19
| | | | | | | | | | | | In the next patch we will want to reinsert a request not at the end of the priority queue, but at the front. Here we split insert_request() into two, the first function retrieves the priority list (for reuse for unsubmit later) and a wrapper function to insert at the end of that list and to schedule the tasklet if we were first. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Michał Winiarski <michal.winiarski@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170916204414.32762-3-chris@chris-wilson.co.uk
* drm/i915/execlists: Move insert_request()Chris Wilson2017-09-181-64/+64
| | | | | | | | | Move insert_request() earlier to avoid a forward declaration in a later patch. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Michał Winiarski <michal.winiarski@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170916204414.32762-2-chris@chris-wilson.co.uk
* drm/i915/execlists: Kick start request processing after a resetChris Wilson2017-09-181-2/+6
| | | | | | | | | | | | | | | | | | | | | | | During a reset, we may skip over completed requests and lost context-switch interrupts. Following the reset, we may then may end up with no active requests in the ELSP (and so do not resubmit to restart the engine), but have a queue of requests ready for execution. This is unlikely, it requires the last request to complete after the hang is detected, but not impossible. The outcome of this is that the engine stalls, possibly leading to full ring and indefinite wait under struct_mutex, eventually leading to a full driver hang. Alternatively, we can solve this by unsubmitting the incomplete requests and just kickstarting the tasklet. Michał has patches for that, which I initially disliked due to the extra complexity, but the complexity of this "simple" restart is growing... Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michał Winiarski <michal.winiarski@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170916204414.32762-1-chris@chris-wilson.co.uk Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
* drm/i915: Cancel all ready but queued requests when wedgingChris Wilson2017-09-181-0/+60
| | | | | | | | | | | | | | | | | | | | When wedging the hw, we want to mark all in-flight requests as -EIO. This is made slightly more complex by execlists who store the ready but not yet submitted-to-hw requests on a private queue (an rbtree priolist). Call into execlists to cancel not only the ELSP tracking for the submitted requests, but also the queue of unsubmitted requests. v2: Move the majority of engine_set_wedged to the backends (both legacy ringbuffer and execlists handling their own lists). Reported-by: Michał Winiarski <michal.winiarski@intel.com> Testcase: igt/gem_eio/in-flight-contexts Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michał Winiarski <michal.winiarski@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170915173100.26470-1-chris@chris-wilson.co.uk Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
* drm/i915/execlists: Read the context-status HEAD from the HWSPChris Wilson2017-09-131-7/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The engine also provides a mirror of the CSB write pointer in the HWSP, but not of our read pointer. To take advantage of this we need to remember where we read up to on the last interrupt and continue off from there. This poses a problem following a reset, as we don't know where the hw will start writing from, and due to the use of power contexts we cannot perform that query during the reset itself. So we continue the current modus operandi of delaying the first read of the context-status read/write pointers until after the first interrupt. With this we should now have eliminated all uncached mmio reads in handling the context-status interrupt, though we still have the uncached mmio writes for submitting new work, and many uncached mmio reads in the global interrupt handler itself. Still a step in the right direction towards reducing our resubmit latency, although it appears lost in the noise! v2: Cannonlake moved the CSB write index v3: Include the sw/hwsp state in debugfs/i915_engine_info v4: Also revert to using CSB mmio for GVT-g v5: Prevent the compiler reloading tail (Mika) Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michel Thierry <michel.thierry@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Acked-by: Michel Thierry <michel.thierry@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170913085605.18299-6-chris@chris-wilson.co.uk Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
* drm/i915/execlists: Read the context-status buffer from the HWSPChris Wilson2017-09-131-5/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The engine provides a mirror of the CSB in the HWSP. If we use the cacheable reads from the HWSP, we can shave off a few mmio reads per context-switch interrupt (which are quite frequent!). Just removing a couple of mmio is not enough to actually reduce any latency, but a small reduction in overall cpu usage. Much appreciation for Ben dropping the bombshell that the CSB was in the HWSP and for Michel in digging out the details. v2: Don't be lazy, add the defines for the indices. v3: Include the HWSP in debugfs/i915_engine_info v4: Check for GVT-g, it currently depends on intercepting CSB mmio v5: Fixup GVT-g mmio path v6: Disable HWSP if VT-d is active as the iommu adds unpredictable memory latency. (Mika) v7: Also markup the CSB read with READ_ONCE() as it may still be an mmio read and we want to stop the compiler from issuing a later (v.slow) reload. Suggested-by: Ben Widawsky <benjamin.widawsky@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michel Thierry <michel.thierry@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Acked-by: Michel Thierry <michel.thierry@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170913133534.26927-1-chris@chris-wilson.co.uk Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
* drm/i915/lrc: allocate separate page for HWSPDaniele Ceraolo Spurio2017-09-131-33/+1
| | | | | | | | | | | | | | | | | | | | | | | On gen8+ we're currently using the PPHWSP of the kernel ctx as the global HWSP. However, when the kernel ctx gets submitted (e.g. from __intel_autoenable_gt_powersave) the HW will use that page as both HWSP and PPHWSP. This causes a conflict in the register arena of the HWSP, i.e. dword indices below 0x30. We don't current utilize this arena, but in the following patches we will take advantage of the cached register state for handling execlist's context status interrupt. To avoid the conflict, instead of re-using the PPHWSP of the kernel ctx we can allocate a separate page for the HWSP like what happens for pre-execlists platform. v2: Add a use-case for the register arena of the HWSP. Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Michel Thierry <michel.thierry@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1499357440-34688-1-git-send-email-daniele.ceraolospurio@intel.com Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Michel Thierry <michel.thierry@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170913085605.18299-3-chris@chris-wilson.co.uk
* drm/i915/lrc: Clarify the format of the context imageMichel Thierry2017-09-131-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Not only the context image consist of two parts (the PPHWSP, and the logical context state), but we also allocate a header at the start of for sharing data with GuC. Thus every lrc looks like this: | [guc] | [hwsp] [logical state] | |<- our header ->|<- context image ->| So far, we have oversimplified whenever we use each of these parts of the context, just because the GuC header happens to be in page 0, and the (PP)HWSP is in page 1. But this had led to using the same define for more than one meaning (as a page index in the lrc and as 1 page). This patch adds defines for the GuC shared page, the PPHWSP page and the start of the logical state. It also updated the places where the old define was being used. Since we are not changing the size (or format) of the context, there are no functional changes. v2: Use PPHWSP index for hws again. Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Michel Thierry <michel.thierry@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Michal Wajdeczko <michal.wajdeczko@intel.com> Cc: Oscar Mateo <oscar.mateo@intel.com> Cc: intel-gvt-dev@lists.freedesktop.org Link: http://patchwork.freedesktop.org/patch/msgid/20170712193032.27080-1-michel.thierry@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/20170913085605.18299-1-chris@chris-wilson.co.uk
* drm/i915: Move the context descriptor to an inline helperChris Wilson2017-09-131-6/+0
| | | | | | | | | | | | | | | | | | | The context descriptor is stored inside the per-engine context state, as we only need to compute it once and access it frequently. However, currently only intel_lrc.c has easy access, but i915_guc_submission.c would like to frequently read it as well, and more so only ever needs the lower 32bits. Make it an inline as the compiler should be able to retrieve the value in less instructions than it takes to do the function call: add/remove: 0/1 grow/shrink: 1/0 up/down: 8/-45 (-37) function old new delta i915_guc_submit 621 629 +8 intel_lr_context_descriptor 45 - -45 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170912214905.21987-1-chris@chris-wilson.co.uk Reviewed-by: Oscar Mateo <oscar.mateo@intel.com>
* drm/i915/cnl: Introduce initial Cannonlake Workarounds.Rodrigo Vivi2017-08-181-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | Let's inherit workarounds from previous platforms that according to wa_database and BSpec are still valid for Cannonlake. v2: Add missed workarounds. v3: Rebase v4: Remove bad chunk that was added to rc6 disable. (Ander) Also remove A0 W/a that are not needed anymore. v5: Rebase on top of CFL. v6: Remove empty gen9_init_perctx_bb and gen9_init_indirectctx_bb since they don't carry any gen10 related W/a. (by Oscar). Also Remove A0 exclusive workaround. v7: Remove more A0 exclusive workarounds. As pointed out by Oscar many workarounds were changed to be A0 only so let's remove them. Cc: Oscar Mateo <oscar.mateo@intel.com> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Reviewed-by: Oscar Mateo <oscar.mateo@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170815231651.975-1-rodrigo.vivi@intel.com
* drm/i915: Clear lost context-switch interrupts across resetChris Wilson2017-08-181-1/+22
| | | | | | | | | | | | | | | | | | | | | | | During a global reset, we disable the irq. As we disable the irq, the hardware may be raising a GT interrupt that we then ignore, leaving it pending in the GTIIR. After the reset, we then re-enable the irq, triggering the pending interrupt. However, that interrupt was for the stale state from before the reset, and the contents of the CSB buffer are now invalid. v2: Add a comment to make it clear that the double clear is purely my paranoia. Reported-by: "Dong, Chuanxiao" <chuanxiao.dong@intel.com> Fixes: 821ed7df6e2a ("drm/i915: Update reset path to fix incomplete requests") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: "Dong, Chuanxiao" <chuanxiao.dong@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Michal Winiarski <michal.winiarski@intel.com> Cc: Michel Thierry <michel.thierry@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170807121919.30165-1-chris@chris-wilson.co.uk Link: https://patchwork.freedesktop.org/patch/msgid/20170818090509.5363-1-chris@chris-wilson.co.uk Reviewed-by: Michel Thierry <michel.thierry@intel.com>
* drm/i915: Flush the execlist ports if idleChris Wilson2017-07-271-10/+26
| | | | | | | | | | | | | | | | When doing a GPU reset, the CSB register will be trashed and we will lose any context-switch notifications that happened since the tasklet was disabled. If we find that all requests on this engine were completed, we want to make sure that the ELSP tracker is similarly empty so that we do not feed back in the completed requests upon recovering from the reset. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170721123238.16428-4-chris@chris-wilson.co.uk Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm/i915: Group all the global context information togetherChris Wilson2017-06-201-1/+1
| | | | | | | | | Create a substruct to hold all the global context state under drm_i915_private. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170620110547.15947-1-chris@chris-wilson.co.uk
* drm/i915/perf: Add OA unit support for Gen 8+Robert Bragg2017-06-141-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enables access to OA unit metrics for BDW, CHV, SKL and BXT which all share (more-or-less) the same OA unit design. Of particular note in comparison to Haswell: some OA unit HW config state has become per-context state and as a consequence it is somewhat more complicated to manage synchronous state changes from the cpu while there's no guarantee of what context (if any) is currently actively running on the gpu. The periodic sampling frequency which can be particularly useful for system-wide analysis (as opposed to command stream synchronised MI_REPORT_PERF_COUNT commands) is perhaps the most surprising state to have become per-context save and restored (while the OABUFFER destination is still a shared, system-wide resource). This support for gen8+ takes care to consider a number of timing challenges involved in synchronously updating per-context state primarily by programming all config state from the cpu and updating all current and saved contexts synchronously while the OA unit is still disabled. The driver intentionally avoids depending on command streamer programming to update OA state considering the lack of synchronization between the automatic loading of OACTXCONTROL state (that includes the periodic sampling state and enable state) on context restore and the parsing of any general purpose BB the driver can control. I.e. this implementation is careful to avoid the possibility of a context restore temporarily enabling any out-of-date periodic sampling state. In addition to the risk of transiently-out-of-date state being loaded automatically; there are also internal HW latencies involved in the loading of MUX configurations which would be difficult to account for from the command streamer (and we only want to enable the unit when once the MUX configuration is complete). Since the Gen8+ OA unit design no longer supports clock gating the unit off for a single given context (which effectively stopped any progress of counters while any other context was running) and instead supports tagging OA reports with a context ID for filtering on the CPU, it means we can no longer hide the system-wide progress of counters from a non-privileged application only interested in metrics for its own context. Although we could theoretically try and subtract the progress of other contexts before forwarding reports via read() we aren't in a position to filter reports captured via MI_REPORT_PERF_COUNT commands. As a result, for Gen8+, we always require the dev.i915.perf_stream_paranoid to be unset for any access to OA metrics if not root. v5: Drain submitted requests when enabling metric set to ensure no lite-restore erases the context image we just updated (Lionel) v6: In addition to drain, switch to kernel context & update all context in place (Chris) v7: Add missing mutex_unlock() if switching to kernel context fails (Matthew) v8: Simplify OA period/flex-eu-counters programming by using the batchbuffer instead of modifying ctx-image (Lionel) v9: Back to updating the context image (due to erroneous testing, batchbuffer programming the OA unit doesn't actually work) (Lionel) Pin context before updating context image (Chris) Drop MMIO programming now that we switch to a kernel context with right values in initial context image (Chris) v10: Just pin_map the contexts we want to modify or let the configuration happen on first use (Chris) v11: Update kernel context OA config through the batchbuffer rather than on the fly ctx-image update (Lionel) v12: Rework OA context registers update again by swithing away from user contexts and reconfiguring the kernel context through the batchbuffer and updating all the other contexts' context image. Also take care to lock slice/subslice configuration when OA is on. (Lionel) v13: Request rpcs updates on all engine when updating the OA config (Lionel) v14: Drop any kind of rpcs management now that we monitor sseu configuration changes in a later patch (Lionel) Remove usleep after programming the NOA configs on Gen8+, this doesn't seem to be needed (Lionel) v15: Respect coding style for block comments (Chris) v16: Add missing i915_add_request() in case we fail to emit OA configuration (Matthew) Signed-off-by: Robert Bragg <robert@sixbynine.org> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> \o/ Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
* drm/i915/gen10: Set value of Indirect Context Offset for gen10Michel Thierry2017-06-071-0/+5
| | | | | | | | | | | | | | | Indirect Context Offset Pointer has changed for Cannonlake. INDIRECT_CTX_OFFSET[15:6] valid value for CNL is 19h per Spec. v2: rebased to intel_lr_indirect_ctx_offset v3: Commit message added per Tvrtko request. Signed-off-by: Michel Thierry <michel.thierry@intel.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1496781040-20888-9-git-send-email-rodrigo.vivi@intel.com
* drm/i915/execlists: Reduce lock contention between schedule/submit_requestChris Wilson2017-05-171-0/+13
| | | | | | | | | | | | | | If we do not require to perform priority bumping, and we haven't yet submitted the request, we can update its priority in situ and skip acquiring the engine locks -- thus avoiding any contention between us and submit/execute. v2: Remove the stack element from the list if we can do the early assignment. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170517121007.27224-10-chris@chris-wilson.co.uk
* drm/i915: Create a kmem_cache to allocate struct i915_priolist fromChris Wilson2017-05-171-2/+2
| | | | | | | | | | | | | | | | The i915_priolist are allocated within an atomic context on a path where we wish to minimise latency. If we use a dedicated kmem_cache, we have the advantage of a local freelist from which to service new requests that should keep the latency impact of an allocation small. Though currently we expect the majority of requests to be at default priority (and so hit the preallocate priolist), once userspace starts using priorities they are likely to use many fine grained policies improving the utilisation of a private slab. 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: http://patchwork.freedesktop.org/patch/msgid/20170517121007.27224-9-chris@chris-wilson.co.uk
* drm/i915: Split execlist priority queue into rbtree + linked listChris Wilson2017-05-171-62/+121
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All the requests at the same priority are executed in FIFO order. They do not need to be stored in the rbtree themselves, as they are a simple list within a level. If we move the requests at one priority into a list, we can then reduce the rbtree to the set of priorities. This should keep the height of the rbtree small, as the number of active priorities can not exceed the number of active requests and should be typically only a few. Currently, we have ~2k possible different priority levels, that may increase to allow even more fine grained selection. Allocating those in advance seems a waste (and may be impossible), so we opt for allocating upon first use, and freeing after its requests are depleted. To avoid the possibility of an allocation failure causing us to lose a request, we preallocate the default priority (0) and bump any request to that priority if we fail to allocate it the appropriate plist. Having a request (that is ready to run, so not leading to corruption) execute out-of-order is better than leaking the request (and its dependency tree) entirely. There should be a benefit to reducing execlists_dequeue() to principally using a simple list (and reducing the frequency of both rbtree iteration and balancing on erase) but for typical workloads, request coalescing should be small enough that we don't notice any change. The main gain is from improving PI calls to schedule, and the explicit list within a level should make request unwinding simpler (we just need to insert at the head of the list rather than the tail and not have to make the rbtree search more complicated). v2: Avoid use-after-free when deleting a depleted priolist v3: Michał found the solution to handling the allocation failure gracefully. If we disable all priority scheduling following the allocation failure, those requests will be executed in fifo and we will ensure that this request and its dependencies are in strict fifo (even when it doesn't realise it is only a single list). Normal scheduling is restored once we know the device is idle, until the next failure! Suggested-by: Michał Wajdeczko <michal.wajdeczko@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michał Winiarski <michal.winiarski@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Michał Winiarski <michal.winiarski@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170517121007.27224-8-chris@chris-wilson.co.uk
* drm/i915/execlists: Pack the count into the low bits of the port.requestChris Wilson2017-05-171-56/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add/remove: 1/1 grow/shrink: 5/4 up/down: 391/-578 (-187) function old new delta execlists_submit_ports 262 471 +209 port_assign.isra - 136 +136 capture 6344 6359 +15 reset_common_ring 438 452 +14 execlists_submit_request 228 238 +10 gen8_init_common_ring 334 341 +7 intel_engine_is_idle 106 105 -1 i915_engine_info 2314 2290 -24 __i915_gem_set_wedged_BKL 485 411 -74 intel_lrc_irq_handler 1789 1604 -185 execlists_update_context 294 - -294 The most important change there is the improve to the intel_lrc_irq_handler and excclist_submit_ports (net improvement since execlists_update_context is now inlined). v2: Use the port_api() for guc as well (even though currently we do not pack any counters in there, yet) and hide all port->request_count inside the helpers. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170517121007.27224-5-chris@chris-wilson.co.uk
* drm/i915: set initialised only when init_context callback is NULLChuanxiao Dong2017-05-121-1/+1
| | | | | | | | | | | | | | | | During execlist_context_deferred_alloc() we presumed that the context is uninitialised (we only just allocated the state object for it!) and chose to optimise away the later call to engine->init_context() if engine->init_context were NULL. This breaks with GVT's contexts that are marked as pre-initialised to avoid us annoyingly calling engine->init_context(). The fix is to not override ce->initialised if it is already true. Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1494497262-24855-1-git-send-email-chuanxiao.dong@intel.com Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
* drm/i915: Use engine->context_pin() to report the intel_ringChris Wilson2017-05-041-9/+8
| | | | | | | | | | | | | | | | | | | Since unifying ringbuffer/execlist submission to use engine->pin_context, we ensure that the intel_ring is available before we start constructing the request. We can therefore move the assignment of the request->ring to the central i915_gem_request_alloc() and not require it in every engine->request_alloc() callback. Another small step towards simplification (of the core, but at a cost of handling error pointers in less important callers of engine->pin_context). v2: Rearrange a few branches to reduce impact of PTR_ERR() on gcc's code generation. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Oscar Mateo <oscar.mateo@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Reviewed-by: Oscar Mateo <oscar.mateo@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170504093308.4137-1-chris@chris-wilson.co.uk
* drm/i915: Sanitize engine context sizesJoonas Lahtinen2017-04-281-53/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Pre-calculate engine context size based on engine class and device generation and store it in the engine instance. v2: - Squash and get rid of hw_context_size (Chris) v3: - Move after MMIO init for probing on Gen7 and 8 (Chris) - Retained rounding (Tvrtko) v4: - Rebase for deferred legacy context allocation Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Paulo Zanoni <paulo.r.zanoni@intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Oscar Mateo <oscar.mateo@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: intel-gvt-dev@lists.freedesktop.org Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
* drm/i915: Differentiate between sw write location into ring and last hw readChris Wilson2017-04-251-4/+2
| | | | | | | | | | | | | | | | | | | | We need to keep track of the last location we ask the hw to read up to (RING_TAIL) separately from our last write location into the ring, so that in the event of a GPU reset we do not tell the HW to proceed into a partially written request (which can happen if that request is waiting for an external signal before being executed). v2: Refactor intel_ring_reset() (Mika) Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100144 Testcase: igt/gem_exec_fence/await-hang Fixes: 821ed7df6e2a ("drm/i915: Update reset path to fix incomplete requests") Fixes: d55ac5bf97c6 ("drm/i915: Defer transfer onto execution timeline to actual hw submission") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170425130049.26147-1-chris@chris-wilson.co.uk Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
* drm/i915: Report request restarts for both execlists/gucChris Wilson2017-04-251-13/+16
| | | | | | | | | | | | | | As we now share the execlist_port[] tracking for both execlists/guc, we can reset the inflight count on both and report which requests are being restarted. Suggested-by: Michel Thierry <michel.thierry@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michel Thierry <michel.thierry@intel.com> Cc: Mika Kuoppala <mika.kuoppala@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170425103835.31871-1-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
* drm/i915/execlists: Document runtime pm for intel_lrc_irq_handler()Chris Wilson2017-04-121-0/+9
| | | | | | | | | | | We indirectly hold the runtime-pm for the intel_lrc_irq_handler() by virtue of dev_priv->gt.awake keeping a wakeref whilst the requests are busy. As this is not obvious from the code, add a comment. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170411175850.2470-1-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
* drm/i915: Use the engine class to get the context sizeDaniele Ceraolo Spurio2017-04-111-10/+19
| | | | | | | | | | | | | | | | | | | | | Technically speaking, the context size is per engine class, not per instance. v2: Add MISSING_CASE (Tvrtko) v3: Rebased v4: Restore the interface back to hiding the class lookup (Chris) Cc: Paulo Zanoni <paulo.r.zanoni@intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Signed-off-by: Oscar Mateo <oscar.mateo@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1491905472-16189-1-git-send-email-oscar.mateo@intel.com Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
* drm/i915: intel_ring.engine is unusedChris Wilson2017-04-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Or rather it is used only by intel_ring_pin() to extract the drm_i915_private which we can easily pass in. As this is a relatively rare operation, save the space in the struct, and as such it is even break even in the extra code for passing around the parameter: add/remove: 0/0 grow/shrink: 2/3 up/down: 15/-15 (0) function old new delta intel_init_ring_buffer 906 918 +12 execlists_context_pin 1308 1311 +3 mock_engine 407 403 -4 intel_engine_create_ring 367 363 -4 intel_ring_pin 326 319 -7 Total: Before=1261794, After=1261794, chg +0.00% v2: Reorder intel_init_ring_buffer to keep the ring setup together: add/remove: 0/0 grow/shrink: 2/3 up/down: 9/-15 (-6) function old new delta intel_init_ring_buffer 906 912 +6 execlists_context_pin 1308 1311 +3 mock_engine 407 403 -4 intel_engine_create_ring 367 363 -4 intel_ring_pin 326 319 -7 Total: Before=1261794, After=1261788, chg -0.00% Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170403113426.25707-1-chris@chris-wilson.co.uk
* Revert "drm/i915: Skip execlists_dequeue() early if the list is empty"Chris Wilson2017-03-291-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 6c943de6686f ("drm/i915: Skip execlists_dequeue() early if the list is empty"). The validity of using READ_ONCE there depends upon having a mb to coordinate the assignment of engine->execlist_first inside submit_request() and checking prior to taking the spinlock in execlists_dequeue(). We wrote "the update to TASKLET_SCHED incurs a memory barrier making this cross-cpu checking safe", but failed to notice that this mb was *conditional* on the execlists being ready, i.e. there wasn't the required mb when it was most necessary! We could install an unconditional memory barrier to fixup the READ_ONCE(): diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 7dd732cb9f57..1ed164b16d44 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -616,6 +616,7 @@ static void execlists_submit_request(struct drm_i915_gem_request *request) if (insert_request(&request->priotree, &engine->execlist_queue)) { engine->execlist_first = &request->priotree.node; + smp_wmb(); if (execlists_elsp_ready(engine)) But we have opted to remove the race as it should be rarely effective, and saves us having to explain the necessary memory barriers which we quite clearly failed at. Reported-and-tested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Fixes: 6c943de6686f ("drm/i915: Skip execlists_dequeue() early if the list is empty") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Michał Winiarski <michal.winiarski@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170329100052.29505-1-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
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