diff options
| author | Alex Xie <AlexBin.Xie@amd.com> | 2017-06-16 09:07:29 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2017-06-19 17:31:22 -0400 |
| commit | 5ac55629d6b3fcde69f46aa772c6e83be0bdcbbf (patch) | |
| tree | 8ed09ff14dd34aa048296aa3a32e92e749e12d34 | |
| parent | 99eea4df901907b9121ad1c726d86c352a5eaca5 (diff) | |
drm/amdgpu: Optimize mutex usage (v4)
In original function amdgpu_bo_list_get, the waiting
for result->lock can be quite long while mutex
bo_list_lock was holding. It can make other tasks
waiting for bo_list_lock for long period.
Secondly, this patch allows several tasks(readers of idr)
to proceed at the same time.
v2: use rcu and kref (Dave Airlie and Christian König)
v3: update v1 commit message (Michel Dänzer)
v4: rebase on upstream (Alex Deucher)
Signed-off-by: Alex Xie <AlexBin.Xie@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu.h | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 40 |
2 files changed, 30 insertions, 12 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index 9f827aca90ee..12d61edb3597 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -869,6 +869,8 @@ struct amdgpu_fpriv { struct amdgpu_bo_list { struct mutex lock; + struct rcu_head rhead; + struct kref refcount; struct amdgpu_bo *gds_obj; struct amdgpu_bo *gws_obj; struct amdgpu_bo *oa_obj; diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c index 7b5c3bb2142e..f621ee115c98 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c @@ -41,6 +41,20 @@ static int amdgpu_bo_list_set(struct amdgpu_device *adev, struct drm_amdgpu_bo_list_entry *info, unsigned num_entries); +static void amdgpu_bo_list_release_rcu(struct kref *ref) +{ + unsigned i; + struct amdgpu_bo_list *list = container_of(ref, struct amdgpu_bo_list, + refcount); + + for (i = 0; i < list->num_entries; ++i) + amdgpu_bo_unref(&list->array[i].robj); + + mutex_destroy(&list->lock); + kvfree(list->array); + kfree_rcu(list, rhead); +} + static int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp, struct drm_amdgpu_bo_list_entry *info, @@ -57,7 +71,7 @@ static int amdgpu_bo_list_create(struct amdgpu_device *adev, /* initialize bo list*/ mutex_init(&list->lock); - + kref_init(&list->refcount); r = amdgpu_bo_list_set(adev, filp, list, info, num_entries); if (r) { kfree(list); @@ -83,14 +97,9 @@ static void amdgpu_bo_list_destroy(struct amdgpu_fpriv *fpriv, int id) mutex_lock(&fpriv->bo_list_lock); list = idr_remove(&fpriv->bo_list_handles, id); - if (list) { - /* Another user may have a reference to this list still */ - mutex_lock(&list->lock); - mutex_unlock(&list->lock); - amdgpu_bo_list_free(list); - } - mutex_unlock(&fpriv->bo_list_lock); + if (list) + kref_put(&list->refcount, amdgpu_bo_list_release_rcu); } static int amdgpu_bo_list_set(struct amdgpu_device *adev, @@ -185,11 +194,17 @@ amdgpu_bo_list_get(struct amdgpu_fpriv *fpriv, int id) { struct amdgpu_bo_list *result; - mutex_lock(&fpriv->bo_list_lock); + rcu_read_lock(); result = idr_find(&fpriv->bo_list_handles, id); - if (result) - mutex_lock(&result->lock); - mutex_unlock(&fpriv->bo_list_lock); + + if (result) { + if (kref_get_unless_zero(&result->refcount)) + mutex_lock(&result->lock); + else + result = NULL; + } + rcu_read_unlock(); + return result; } @@ -227,6 +242,7 @@ void amdgpu_bo_list_get_list(struct amdgpu_bo_list *list, void amdgpu_bo_list_put(struct amdgpu_bo_list *list) { mutex_unlock(&list->lock); + kref_put(&list->refcount, amdgpu_bo_list_release_rcu); } void amdgpu_bo_list_free(struct amdgpu_bo_list *list) |