From:   Asahi Lina <lina@asahilina.net>
Date:   Tue, 07 Mar 2023 23:25:35 +0900
Subject: [PATCH RFC 10/18] drm/scheduler: Add can_run_job callback
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To:     Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        =?utf-8?q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>,
        Luben Tuikov <luben.tuikov@amd.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>
Cc:     Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        Karol Herbst <kherbst@redhat.com>,
        Ella Stanforth <ella@iglunix.org>,
        Faith Ekstrand <faith.ekstrand@collabora.com>,
        Mary <mary@mary.zone>, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org,
        linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org,
        linux-sgx@vger.kernel.org, asahi@lists.linux.dev,
        Asahi Lina <lina@asahilina.net>
Precedence: bulk

Some hardware may require more complex resource utilization accounting
than the simple job count supported by drm_sched internally. Add a
can_run_job callback to allow drivers to implement more logic before
deciding whether to run a GPU job.

Signed-off-by: Asahi Lina <lina@asahilina.net>
---
 drivers/gpu/drm/scheduler/sched_main.c | 10 ++++++++++
 include/drm/gpu_scheduler.h            |  8 ++++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 4e6ad6e122bc..5c0add2c7546 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -1001,6 +1001,16 @@ static int drm_sched_main(void *param)
 		if (!entity)
 			continue;
 
+		if (sched->ops->can_run_job) {
+			sched_job = to_drm_sched_job(spsc_queue_peek(&entity->job_queue));
+			if (!sched_job) {
+				complete_all(&entity->entity_idle);
+				continue;
+			}
+			if (!sched->ops->can_run_job(sched_job))
+				continue;
+		}
+
 		sched_job = drm_sched_entity_pop_job(entity);
 
 		if (!sched_job) {
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 9db9e5e504ee..bd89ea9507b9 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -396,6 +396,14 @@ struct drm_sched_backend_ops {
 	struct dma_fence *(*prepare_job)(struct drm_sched_job *sched_job,
 					 struct drm_sched_entity *s_entity);
 
+	/**
+	 * @can_run_job: Called before job execution to check whether the
+	 * hardware is free enough to run the job.  This can be used to
+	 * implement more complex hardware resource policies than the
+	 * hw_submission limit.
+	 */
+	bool (*can_run_job)(struct drm_sched_job *sched_job);
+
 	/**
          * @run_job: Called to execute the job once all of the dependencies
          * have been resolved.  This may be called multiple times, if

-- 
2.35.1