diff options
| author | Dave Gordon | 2016-05-13 16:36:33 +0200 |
|---|---|---|
| committer | Tvrtko Ursulin | 2016-05-23 15:21:53 +0200 |
| commit | 551aaecd8873b728a85c1fcb2b8ca502e9ffc49c (patch) | |
| tree | 2f9890e8f01bd619da27eecb7a7be23b658f823c /drivers/gpu/drm/i915/intel_guc.h | |
| parent | drm/i915/guc: pass request (not client) to i915_guc_{wq_check_space, submit}() (diff) | |
| download | kernel-qcow2-linux-551aaecd8873b728a85c1fcb2b8ca502e9ffc49c.tar.gz kernel-qcow2-linux-551aaecd8873b728a85c1fcb2b8ca502e9ffc49c.tar.xz kernel-qcow2-linux-551aaecd8873b728a85c1fcb2b8ca502e9ffc49c.zip | |
drm/i915/guc: don't spinwait if the GuC's workqueue is full
Rather than wait to see whether more space becomes available in the GuC
submission workqueue, we can just return -EAGAIN and let the caller try
again in a little while. This gets rid of an uninterruptable sleep in
the polling code :)
We'll also add a counter to the GuC client statistics, to see how often
we find the WQ full.
v2:
Flag the likely() code path (Tvtrko Ursulin).
v4:
Add/update comments about failure counters (Tvtrko Ursulin).
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_guc.h')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_guc.h | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h index 91f315cf073b..380a743f830f 100644 --- a/drivers/gpu/drm/i915/intel_guc.h +++ b/drivers/gpu/drm/i915/intel_guc.h @@ -48,9 +48,18 @@ struct drm_i915_gem_request; * queue (a circular array of work items), again described in the process * descriptor. Work queue pages are mapped momentarily as required. * - * Finally, we also keep a few statistics here, including the number of - * submissions to each engine, and a record of the last submission failure - * (if any). + * We also keep a few statistics on failures. Ideally, these should all + * be zero! + * no_wq_space: times that the submission pre-check found no space was + * available in the work queue (note, the queue is shared, + * not per-engine). It is OK for this to be nonzero, but + * it should not be huge! + * q_fail: failed to enqueue a work item. This should never happen, + * because we check for space beforehand. + * b_fail: failed to ring the doorbell. This should never happen, unless + * somehow the hardware misbehaves, or maybe if the GuC firmware + * crashes? We probably need to reset the GPU to recover. + * retcode: errno from last guc_submit() */ struct i915_guc_client { struct drm_i915_gem_object *client_obj; @@ -71,12 +80,13 @@ struct i915_guc_client { uint32_t wq_tail; uint32_t unused; /* Was 'wq_head' */ - /* GuC submission statistics & status */ - uint64_t submissions[GUC_MAX_ENGINES_NUM]; + uint32_t no_wq_space; uint32_t q_fail; uint32_t b_fail; int retcode; - int spare; /* pad to 32 DWords */ + + /* Per-engine counts of GuC submissions */ + uint64_t submissions[GUC_MAX_ENGINES_NUM]; }; enum intel_guc_fw_status { |