Re: [Intel-gfx] [PATCH 1/6] drm/i915: Individual request cancellation

2021-03-23 Thread Tvrtko Ursulin



On 22/03/2021 15:38, Matthew Auld wrote:

On Thu, 18 Mar 2021 at 17:04, Tvrtko Ursulin
 wrote:


From: Chris Wilson 

Currently, we cancel outstanding requests within a context when the
context is closed. We may also want to cancel individual requests using
the same graceful preemption mechanism.

v2 (Tvrtko):
  * Cancel waiters carefully considering no timeline lock and RCU.
  * Fixed selftests.

v3 (Tvrtko):
  * Remove error propagation to waiters for now.

Signed-off-by: Chris Wilson 
Signed-off-by: Tvrtko Ursulin 
---
  .../gpu/drm/i915/gt/intel_engine_heartbeat.c  |   1 +
  .../drm/i915/gt/intel_execlists_submission.c  |   9 +-
  drivers/gpu/drm/i915/i915_request.c   |  52 -
  drivers/gpu/drm/i915/i915_request.h   |   4 +-
  drivers/gpu/drm/i915/selftests/i915_request.c | 201 ++
  5 files changed, 261 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c 
b/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c
index 0b062fad1837..e2fb3ae2aaf3 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c
@@ -314,6 +314,7 @@ int intel_engine_pulse(struct intel_engine_cs *engine)
 mutex_unlock(>timeline->mutex);
 }

+   intel_engine_flush_scheduler(engine);
 intel_engine_pm_put(engine);
 return err;
  }
diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c 
b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
index 85ff5fe861b4..4c2acb5a6c0a 100644
--- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
@@ -421,6 +421,11 @@ static void reset_active(struct i915_request *rq,
 ce->lrc.lrca = lrc_update_regs(ce, engine, head);
  }

+static bool bad_request(const struct i915_request *rq)
+{
+   return rq->fence.error && i915_request_started(rq);
+}
+
  static struct intel_engine_cs *
  __execlists_schedule_in(struct i915_request *rq)
  {
@@ -433,7 +438,7 @@ __execlists_schedule_in(struct i915_request *rq)
  !intel_engine_has_heartbeat(engine)))
 intel_context_set_banned(ce);

-   if (unlikely(intel_context_is_banned(ce)))
+   if (unlikely(intel_context_is_banned(ce) || bad_request(rq)))
 reset_active(rq, engine);

 if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
@@ -1112,7 +1117,7 @@ static unsigned long active_preempt_timeout(struct 
intel_engine_cs *engine,
 return 0;

 /* Force a fast reset for terminated contexts (ignoring sysfs!) */
-   if (unlikely(intel_context_is_banned(rq->context)))
+   if (unlikely(intel_context_is_banned(rq->context) || bad_request(rq)))
 return 1;

 return READ_ONCE(engine->props.preempt_timeout_ms);
diff --git a/drivers/gpu/drm/i915/i915_request.c 
b/drivers/gpu/drm/i915/i915_request.c
index e7b4c4bc41a6..b4511ac05e9a 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -33,7 +33,10 @@
  #include "gem/i915_gem_context.h"
  #include "gt/intel_breadcrumbs.h"
  #include "gt/intel_context.h"
+#include "gt/intel_engine.h"
+#include "gt/intel_engine_heartbeat.h"
  #include "gt/intel_gpu_commands.h"
+#include "gt/intel_reset.h"
  #include "gt/intel_ring.h"
  #include "gt/intel_rps.h"

@@ -429,20 +432,22 @@ void __i915_request_skip(struct i915_request *rq)
 rq->infix = rq->postfix;
  }

-void i915_request_set_error_once(struct i915_request *rq, int error)
+bool i915_request_set_error_once(struct i915_request *rq, int error)
  {
 int old;

 GEM_BUG_ON(!IS_ERR_VALUE((long)error));

 if (i915_request_signaled(rq))
-   return;
+   return false;

 old = READ_ONCE(rq->fence.error);
 do {
 if (fatal_error(old))
-   return;
+   return false;
 } while (!try_cmpxchg(>fence.error, , error));
+
+   return true;
  }

  struct i915_request *i915_request_mark_eio(struct i915_request *rq)
@@ -609,6 +614,47 @@ void i915_request_unsubmit(struct i915_request *request)
 spin_unlock_irqrestore(>lock, flags);
  }

+static struct intel_engine_cs *active_engine(struct i915_request *rq)
+{
+   struct intel_engine_cs *engine, *locked;
+
+   locked = READ_ONCE(rq->engine);
+   spin_lock_irq(>sched.lock);
+   while (unlikely(locked != (engine = READ_ONCE(rq->engine {
+   spin_unlock(>sched.lock);
+   locked = engine;
+   spin_lock(>sched.lock);
+   }
+
+   engine = NULL;
+   if (i915_request_is_active(rq) && !__i915_request_is_complete(rq))
+   engine = locked;
+
+   spin_unlock_irq(>sched.lock);
+
+   return engine;


Bad idea to reuse __active_engine() somehow?


I can try and see how it ends up looking.


Reviewed-by: Matthew Auld 



Thanks,

Tvrtko

Re: [Intel-gfx] [PATCH 1/6] drm/i915: Individual request cancellation

2021-03-22 Thread Matthew Auld
On Thu, 18 Mar 2021 at 17:04, Tvrtko Ursulin
 wrote:
>
> From: Chris Wilson 
>
> Currently, we cancel outstanding requests within a context when the
> context is closed. We may also want to cancel individual requests using
> the same graceful preemption mechanism.
>
> v2 (Tvrtko):
>  * Cancel waiters carefully considering no timeline lock and RCU.
>  * Fixed selftests.
>
> v3 (Tvrtko):
>  * Remove error propagation to waiters for now.
>
> Signed-off-by: Chris Wilson 
> Signed-off-by: Tvrtko Ursulin 
> ---
>  .../gpu/drm/i915/gt/intel_engine_heartbeat.c  |   1 +
>  .../drm/i915/gt/intel_execlists_submission.c  |   9 +-
>  drivers/gpu/drm/i915/i915_request.c   |  52 -
>  drivers/gpu/drm/i915/i915_request.h   |   4 +-
>  drivers/gpu/drm/i915/selftests/i915_request.c | 201 ++
>  5 files changed, 261 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c 
> b/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c
> index 0b062fad1837..e2fb3ae2aaf3 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c
> +++ b/drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c
> @@ -314,6 +314,7 @@ int intel_engine_pulse(struct intel_engine_cs *engine)
> mutex_unlock(>timeline->mutex);
> }
>
> +   intel_engine_flush_scheduler(engine);
> intel_engine_pm_put(engine);
> return err;
>  }
> diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c 
> b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> index 85ff5fe861b4..4c2acb5a6c0a 100644
> --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
> @@ -421,6 +421,11 @@ static void reset_active(struct i915_request *rq,
> ce->lrc.lrca = lrc_update_regs(ce, engine, head);
>  }
>
> +static bool bad_request(const struct i915_request *rq)
> +{
> +   return rq->fence.error && i915_request_started(rq);
> +}
> +
>  static struct intel_engine_cs *
>  __execlists_schedule_in(struct i915_request *rq)
>  {
> @@ -433,7 +438,7 @@ __execlists_schedule_in(struct i915_request *rq)
>  !intel_engine_has_heartbeat(engine)))
> intel_context_set_banned(ce);
>
> -   if (unlikely(intel_context_is_banned(ce)))
> +   if (unlikely(intel_context_is_banned(ce) || bad_request(rq)))
> reset_active(rq, engine);
>
> if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
> @@ -1112,7 +1117,7 @@ static unsigned long active_preempt_timeout(struct 
> intel_engine_cs *engine,
> return 0;
>
> /* Force a fast reset for terminated contexts (ignoring sysfs!) */
> -   if (unlikely(intel_context_is_banned(rq->context)))
> +   if (unlikely(intel_context_is_banned(rq->context) || bad_request(rq)))
> return 1;
>
> return READ_ONCE(engine->props.preempt_timeout_ms);
> diff --git a/drivers/gpu/drm/i915/i915_request.c 
> b/drivers/gpu/drm/i915/i915_request.c
> index e7b4c4bc41a6..b4511ac05e9a 100644
> --- a/drivers/gpu/drm/i915/i915_request.c
> +++ b/drivers/gpu/drm/i915/i915_request.c
> @@ -33,7 +33,10 @@
>  #include "gem/i915_gem_context.h"
>  #include "gt/intel_breadcrumbs.h"
>  #include "gt/intel_context.h"
> +#include "gt/intel_engine.h"
> +#include "gt/intel_engine_heartbeat.h"
>  #include "gt/intel_gpu_commands.h"
> +#include "gt/intel_reset.h"
>  #include "gt/intel_ring.h"
>  #include "gt/intel_rps.h"
>
> @@ -429,20 +432,22 @@ void __i915_request_skip(struct i915_request *rq)
> rq->infix = rq->postfix;
>  }
>
> -void i915_request_set_error_once(struct i915_request *rq, int error)
> +bool i915_request_set_error_once(struct i915_request *rq, int error)
>  {
> int old;
>
> GEM_BUG_ON(!IS_ERR_VALUE((long)error));
>
> if (i915_request_signaled(rq))
> -   return;
> +   return false;
>
> old = READ_ONCE(rq->fence.error);
> do {
> if (fatal_error(old))
> -   return;
> +   return false;
> } while (!try_cmpxchg(>fence.error, , error));
> +
> +   return true;
>  }
>
>  struct i915_request *i915_request_mark_eio(struct i915_request *rq)
> @@ -609,6 +614,47 @@ void i915_request_unsubmit(struct i915_request *request)
> spin_unlock_irqrestore(>lock, flags);
>  }
>
> +static struct intel_engine_cs *active_engine(struct i915_request *rq)
> +{
> +   struct intel_engine_cs *engine, *locked;
> +
> +   locked = READ_ONCE(rq->engine);
> +   spin_lock_irq(>sched.lock);
> +   while (unlikely(locked != (engine = READ_ONCE(rq->engine {
> +   spin_unlock(>sched.lock);
> +   locked = engine;
> +   spin_lock(>sched.lock);
> +   }
> +
> +   engine = NULL;
> +   if (i915_request_is_active(rq) && !__i915_request_is_complete(rq))
> +   engine = locked;
> +
> +   spin_unlock_irq(>sched.lock);
> +
> +   return