| Message ID | 20191010071434.31195-5-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/10] drm/i915: Note the addition of timeslicing to the pretend scheduler | expand |
On 10/10/2019 08:14, Chris Wilson wrote: > Sometimes we want to emit a terminator request, a request that flushes > the pipeline and allows no request to come after it. This can be used > for a "preempt-to-idle" to ensure that upon processing the > context-switch to that request, all other active contexts have been > flushed. > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > --- > drivers/gpu/drm/i915/gt/intel_lrc.c | 6 ++++++ > drivers/gpu/drm/i915/i915_request.h | 10 ++++++++-- > 2 files changed, 14 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c > index aa52e5f34dab..eb99f1e804f7 100644 > --- a/drivers/gpu/drm/i915/gt/intel_lrc.c > +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c > @@ -1253,6 +1253,9 @@ static bool can_merge_rq(const struct i915_request *prev, > if (i915_request_completed(next)) > return true; > > + if (i915_request_has_sentinel(prev)) > + return false; > + > if (!can_merge_ctx(prev->hw_context, next->hw_context)) > return false; > > @@ -1724,6 +1727,9 @@ static void execlists_dequeue(struct intel_engine_cs *engine) > if (last->hw_context == rq->hw_context) > goto done; > > + if (i915_request_has_sentinel(last)) > + goto done; > + > /* > * If GVT overrides us we only ever submit > * port[0], leaving port[1] empty. Note that we > diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h > index 6a95242b280d..96991d64759c 100644 > --- a/drivers/gpu/drm/i915/i915_request.h > +++ b/drivers/gpu/drm/i915/i915_request.h > @@ -216,8 +216,9 @@ struct i915_request { > unsigned long emitted_jiffies; > > unsigned long flags; > -#define I915_REQUEST_WAITBOOST BIT(0) > -#define I915_REQUEST_NOPREEMPT BIT(1) > +#define I915_REQUEST_WAITBOOST BIT(0) > +#define I915_REQUEST_NOPREEMPT BIT(1) > +#define I915_REQUEST_SENTINEL BIT(2) > > /** timeline->request entry for this request */ > struct list_head link; > @@ -440,6 +441,11 @@ static inline bool i915_request_has_nopreempt(const struct i915_request *rq) > return unlikely(rq->flags & I915_REQUEST_NOPREEMPT); > } > > +static inline bool i915_request_has_sentinel(const struct i915_request *rq) > +{ > + return unlikely(rq->flags & I915_REQUEST_SENTINEL); > +} > + > static inline struct intel_timeline * > i915_request_timeline(struct i915_request *rq) > { > Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Regards, Tvrtko
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c index aa52e5f34dab..eb99f1e804f7 100644 --- a/drivers/gpu/drm/i915/gt/intel_lrc.c +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c @@ -1253,6 +1253,9 @@ static bool can_merge_rq(const struct i915_request *prev, if (i915_request_completed(next)) return true; + if (i915_request_has_sentinel(prev)) + return false; + if (!can_merge_ctx(prev->hw_context, next->hw_context)) return false; @@ -1724,6 +1727,9 @@ static void execlists_dequeue(struct intel_engine_cs *engine) if (last->hw_context == rq->hw_context) goto done; + if (i915_request_has_sentinel(last)) + goto done; + /* * If GVT overrides us we only ever submit * port[0], leaving port[1] empty. Note that we diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h index 6a95242b280d..96991d64759c 100644 --- a/drivers/gpu/drm/i915/i915_request.h +++ b/drivers/gpu/drm/i915/i915_request.h @@ -216,8 +216,9 @@ struct i915_request { unsigned long emitted_jiffies; unsigned long flags; -#define I915_REQUEST_WAITBOOST BIT(0) -#define I915_REQUEST_NOPREEMPT BIT(1) +#define I915_REQUEST_WAITBOOST BIT(0) +#define I915_REQUEST_NOPREEMPT BIT(1) +#define I915_REQUEST_SENTINEL BIT(2) /** timeline->request entry for this request */ struct list_head link; @@ -440,6 +441,11 @@ static inline bool i915_request_has_nopreempt(const struct i915_request *rq) return unlikely(rq->flags & I915_REQUEST_NOPREEMPT); } +static inline bool i915_request_has_sentinel(const struct i915_request *rq) +{ + return unlikely(rq->flags & I915_REQUEST_SENTINEL); +} + static inline struct intel_timeline * i915_request_timeline(struct i915_request *rq) {
Sometimes we want to emit a terminator request, a request that flushes the pipeline and allows no request to come after it. This can be used for a "preempt-to-idle" to ensure that upon processing the context-switch to that request, all other active contexts have been flushed. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/gt/intel_lrc.c | 6 ++++++ drivers/gpu/drm/i915/i915_request.h | 10 ++++++++-- 2 files changed, 14 insertions(+), 2 deletions(-)