From c5cf9a9147ff6fc9f87251a8f8a5b6ac8b8bdcdc Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed, 17 May 2017 13:10:04 +0100
Subject: [PATCH] drm/i915: Create a kmem_cache to allocate struct
i915_priolist from
The i915_priolist are allocated within an atomic context on a path where
we wish to minimise latency. If we use a dedicated kmem_cache, we have
the advantage of a local freelist from which to service new requests
that should keep the latency impact of an allocation small. Though
currently we expect the majority of requests to be at default priority
(and so hit the preallocate priolist), once userspace starts using
priorities they are likely to use many fine grained policies improving
the utilisation of a private slab.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170517121007.27224-9-chris@chris-wilson.co.uk
---
drivers/gpu/drm/i915/i915_drv.h | 1 +
drivers/gpu/drm/i915/i915_gem.c | 9 ++++++++-
drivers/gpu/drm/i915/i915_guc_submission.c | 2 +-
drivers/gpu/drm/i915/intel_lrc.c | 4 ++--
drivers/gpu/drm/i915/selftests/mock_gem_device.c | 9 ++++++++-
5 files changed, 20 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a6f20471b4cd..08ee5c8834fb 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2027,6 +2027,7 @@ struct drm_i915_private {
struct kmem_cache *vmas;
struct kmem_cache *requests;
struct kmem_cache *dependencies;
+ struct kmem_cache *priorities;
const struct intel_device_info info;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 3d9161c8c1a1..0680bd2e635a 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4866,12 +4866,16 @@ i915_gem_load_init(struct drm_i915_private *dev_priv)
if (!dev_priv->dependencies)
goto err_requests;
+ dev_priv->priorities = KMEM_CACHE(i915_priolist, SLAB_HWCACHE_ALIGN);
+ if (!dev_priv->priorities)
+ goto err_dependencies;
+
mutex_lock(&dev_priv->drm.struct_mutex);
INIT_LIST_HEAD(&dev_priv->gt.timelines);
err = i915_gem_timeline_init__global(dev_priv);
mutex_unlock(&dev_priv->drm.struct_mutex);
if (err)
- goto err_dependencies;
+ goto err_priorities;
INIT_LIST_HEAD(&dev_priv->context_list);
INIT_WORK(&dev_priv->mm.free_work, __i915_gem_free_work);
@@ -4895,6 +4899,8 @@ i915_gem_load_init(struct drm_i915_private *dev_priv)
return 0;
+err_priorities:
+ kmem_cache_destroy(dev_priv->priorities);
err_dependencies:
kmem_cache_destroy(dev_priv->dependencies);
err_requests:
@@ -4918,6 +4924,7 @@ void i915_gem_load_cleanup(struct drm_i915_private *dev_priv)
WARN_ON(!list_empty(&dev_priv->gt.timelines));
mutex_unlock(&dev_priv->drm.struct_mutex);
+ kmem_cache_destroy(dev_priv->priorities);
kmem_cache_destroy(dev_priv->dependencies);
kmem_cache_destroy(dev_priv->requests);
kmem_cache_destroy(dev_priv->vmas);
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index 3b9cdb0907c2..b3da056ea8f1 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -704,7 +704,7 @@ static bool i915_guc_dequeue(struct intel_engine_cs *engine)
rb_erase(&p->node, &engine->execlist_queue);
INIT_LIST_HEAD(&p->requests);
if (p->priority != I915_PRIORITY_NORMAL)
- kfree(p);
+ kmem_cache_free(engine->i915->priorities, p);
}
done:
engine->execlist_first = rb;
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 626db6185a21..8529746dd7cc 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -499,7 +499,7 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
rb_erase(&p->node, &engine->execlist_queue);
INIT_LIST_HEAD(&p->requests);
if (p->priority != I915_PRIORITY_NORMAL)
- kfree(p);
+ kmem_cache_free(engine->i915->priorities, p);
}
done:
engine->execlist_first = rb;
@@ -661,7 +661,7 @@ insert_request(struct intel_engine_cs *engine,
if (prio == I915_PRIORITY_NORMAL) {
p = &engine->default_priolist;
} else {
- p = kmalloc(sizeof(*p), GFP_ATOMIC);
+ p = kmem_cache_alloc(engine->i915->priorities, GFP_ATOMIC);
/* Convert an allocation failure to a priority bump */
if (unlikely(!p)) {
prio = I915_PRIORITY_NORMAL; /* recurses just once */
diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
index f321bdfe0b5b..3d0e313497d0 100644
--- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c
+++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
@@ -74,6 +74,7 @@ static void mock_device_release(struct drm_device *dev)
destroy_workqueue(i915->wq);
+ kmem_cache_destroy(i915->priorities);
kmem_cache_destroy(i915->dependencies);
kmem_cache_destroy(i915->requests);
kmem_cache_destroy(i915->vmas);
@@ -186,12 +187,16 @@ struct drm_i915_private *mock_gem_device(void)
if (!i915->dependencies)
goto err_requests;
+ i915->priorities = KMEM_CACHE(i915_priolist, SLAB_HWCACHE_ALIGN);
+ if (!i915->priorities)
+ goto err_dependencies;
+
mutex_lock(&i915->drm.struct_mutex);
INIT_LIST_HEAD(&i915->gt.timelines);
err = i915_gem_timeline_init__global(i915);
if (err) {
mutex_unlock(&i915->drm.struct_mutex);
- goto err_dependencies;
+ goto err_priorities;
}
mock_init_ggtt(i915);
@@ -211,6 +216,8 @@ struct drm_i915_private *mock_gem_device(void)
err_engine:
for_each_engine(engine, i915, id)
mock_engine_free(engine);
+err_priorities:
+ kmem_cache_destroy(i915->priorities);
err_dependencies:
kmem_cache_destroy(i915->dependencies);
err_requests:
--
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