<div dir="ltr"><div dir="ltr">Hi Tvrtko, </div> <div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Nov 6, 2018 at 3:14 PM Tvrtko Ursulin <<a href="mailto:tvrtko.ursulin@linux.intel.com">tvrtko.ursulin@linux.intel.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"> On 06/11/2018 04:13, Ankit Navik wrote: > From: Praveen Diwakar <<a href="mailto:praveen.diwakar@intel.com" target="_blank">praveen.diwakar@intel.com</a>> > > This patch gives us the active pending request count which is yet > to be submitted to the GPU > > Signed-off-by: Praveen Diwakar <<a href="mailto:praveen.diwakar@intel.com" target="_blank">praveen.diwakar@intel.com</a>> > Signed-off-by: Yogesh Marathe <<a href="mailto:yogesh.marathe@intel.com" target="_blank">yogesh.marathe@intel.com</a>> > Signed-off-by: Aravindan Muthukumar <<a href="mailto:aravindan.muthukumar@intel.com" target="_blank">aravindan.muthukumar@intel.com</a>> > Signed-off-by: Kedar J Karanje <<a href="mailto:kedar.j.karanje@intel.com" target="_blank">kedar.j.karanje@intel.com</a>> > Signed-off-by: Ankit Navik <<a href="mailto:ankit.p.navik@intel.com" target="_blank">ankit.p.navik@intel.com</a>> > Suggested-by: Tvrtko Ursulin <<a href="mailto:tvrtko.ursulin@linux.intel.com" target="_blank">tvrtko.ursulin@linux.intel.com</a>> > --- > drivers/gpu/drm/i915/i915_drv.c | 1 + > drivers/gpu/drm/i915/i915_drv.h | 5 +++++ > drivers/gpu/drm/i915/i915_gem_context.c | 1 + > drivers/gpu/drm/i915/i915_gem_context.h | 6 ++++++ > drivers/gpu/drm/i915/i915_gem_execbuffer.c | 5 +++++ > drivers/gpu/drm/i915/intel_lrc.c | 6 ++++++ > 6 files changed, 24 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c > index f8cfd16..d37c46e 100644 > --- a/drivers/gpu/drm/i915/i915_drv.c > +++ b/drivers/gpu/drm/i915/i915_drv.c > @@ -903,6 +903,7 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv, > mutex_init(&dev_priv->av_mutex); > mutex_init(&dev_priv->wm.wm_mutex); > mutex_init(&dev_priv->pps_mutex); > + mutex_init(&dev_priv->pred_mutex); > > i915_memcpy_init_early(dev_priv); > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > index 4aca534..137ec33 100644 > --- a/drivers/gpu/drm/i915/i915_drv.h > +++ b/drivers/gpu/drm/i915/i915_drv.h > @@ -1609,6 +1609,11 @@ struct drm_i915_private { > * controller on different i2c buses. */ > struct mutex gmbus_mutex; > > + /** pred_mutex protects against councurrent usage of pending > + * request counter for multiple contexts > + */ > + struct mutex pred_mutex; > + > /** > * Base address of the gmbus and gpio block. > */ > diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c > index b10770c..0bcbe32 100644 > --- a/drivers/gpu/drm/i915/i915_gem_context.c > +++ b/drivers/gpu/drm/i915/i915_gem_context.c > @@ -387,6 +387,7 @@ i915_gem_create_context(struct drm_i915_private *dev_priv, > } > > trace_i915_context_create(ctx); > + atomic_set(&ctx->req_cnt, 0); > > return ctx; > } > diff --git a/drivers/gpu/drm/i915/i915_gem_context.h b/drivers/gpu/drm/i915/i915_gem_context.h > index b116e49..04e3ff7 100644 > --- a/drivers/gpu/drm/i915/i915_gem_context.h > +++ b/drivers/gpu/drm/i915/i915_gem_context.h > @@ -194,6 +194,12 @@ struct i915_gem_context { > * context close. > */ > struct list_head handles_list; > + > + /** req_cnt: tracks the pending commands, based on which we decide to > + * go for low/medium/high load configuration of the GPU, this is > + * controlled via a mutex > + */ > + atomic_t req_cnt; > }; > > static inline bool i915_gem_context_is_closed(const struct i915_gem_context *ctx) > diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c > index 3f0c612..8afa2a5 100644 > --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c > +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c > @@ -2178,6 +2178,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, > struct drm_syncobj **fences) > { > struct i915_execbuffer eb; > + struct drm_i915_private *dev_priv = to_i915(dev); > struct dma_fence *in_fence = NULL; > struct sync_file *out_fence = NULL; > int out_fence_fd = -1; > @@ -2390,6 +2391,10 @@ i915_gem_do_execbuffer(struct drm_device *dev, > */ > eb.request->batch = eb.batch; > > + mutex_lock(&dev_priv->pred_mutex); > + atomic_inc(&eb.ctx->req_cnt); Point of going to atomic_t was to remove need for the mutex. > + mutex_unlock(&dev_priv->pred_mutex); > + > trace_i915_request_queue(eb.request, eb.batch_flags); > err = eb_submit(&eb); > err_request: > diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c > index 1744792..bcbb66b 100644 > --- a/drivers/gpu/drm/i915/intel_lrc.c > +++ b/drivers/gpu/drm/i915/intel_lrc.c > @@ -728,6 +728,12 @@ static void execlists_dequeue(struct intel_engine_cs *engine) > trace_i915_request_in(rq, port_index(port, execlists)); > last = rq; > submit = true; > + > + mutex_lock(&rq->i915->pred_mutex); > + if (atomic_read(&rq->gem_context->req_cnt) > 0) > + atomic_dec(&rq->gem_context->req_cnt); Hitting underflow is a hint accounting does not work as expected. I really think you need to fix it by gathering some ideas from the patches I've pointed at in the previous round. </blockquote><div> </div><div>I have submitted the patch v4. I have tried with point which you have suggested, but didnt see much</div><div>power benefit with that. </div><div> </div><div>Regards, Ankit</div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"> And there is also GuC to think about. Regards, Tvrtko > + > + mutex_unlock(&rq->i915->pred_mutex); > } > > rb_erase_cached(&p->node, &execlists->queue); > _______________________________________________ Intel-gfx mailing list <a href="mailto:Intel-gfx@lists.freedesktop.org" target="_blank">Intel-gfx@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/intel-gfx" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/intel-gfx</a> </blockquote></div></div>