diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2016-04-09 10:57:54 +0100 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2016-04-09 12:09:05 +0100 |
| commit | c04e0f3b4ea01b3b1d81ccfce0a73bb0b297ba46 (patch) | |
| tree | e2123092223d8c5365624d207021eb42f401863f /drivers/gpu/drm/i915/i915_irq.c | |
| parent | 9b9ed3093613288247a27a55a6dd07f1222150f1 (diff) | |
drm/i915: Separate out the seqno-barrier from engine->get_seqno
In order to simplify future patches, extract the
lazy_coherency optimisation our of the engine->get_seqno() vfunc into
its own callback.
v2: Rename the barrier to engine->irq_seqno_barrier to try and better
reflect that the barrier is only required after the user interrupt before
reading the seqno (to ensure that the seqno update lands in time as we
do not have strict seqno-irq ordering on all platforms).
Reviewed-by: Dave Gordon <david.s.gordon@intel.com> [#v2]
v3: Comments for hangcheck paranoia. Mika wanted to keep the extra
barrier inside the hangcheck, just in case. I can argue that it doesn't
provide a barrier against anything, but the side-effects of applying the
barrier may prevent a false declaration of a hung GPU.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1460195877-20520-2-git-send-email-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/gpu/drm/i915/i915_irq.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_irq.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index c30a12ef6daf..3b946e1c7614 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -2941,7 +2941,7 @@ static int semaphore_passed(struct intel_engine_cs *engine) if (signaller->hangcheck.deadlock >= I915_NUM_ENGINES) return -1; - if (i915_seqno_passed(signaller->get_seqno(signaller, false), seqno)) + if (i915_seqno_passed(signaller->get_seqno(signaller), seqno)) return 1; /* cursory check for an unkickable deadlock */ @@ -3100,8 +3100,18 @@ static void i915_hangcheck_elapsed(struct work_struct *work) semaphore_clear_deadlocks(dev_priv); - seqno = engine->get_seqno(engine, false); + /* We don't strictly need an irq-barrier here, as we are not + * serving an interrupt request, be paranoid in case the + * barrier has side-effects (such as preventing a broken + * cacheline snoop) and so be sure that we can see the seqno + * advance. If the seqno should stick, due to a stale + * cacheline, we would erroneously declare the GPU hung. + */ + if (engine->irq_seqno_barrier) + engine->irq_seqno_barrier(engine); + acthd = intel_ring_get_active_head(engine); + seqno = engine->get_seqno(engine); if (engine->hangcheck.seqno == seqno) { if (ring_idle(engine, seqno)) { |