Re: [PATCH 04/11] drm/syncobj: use only a single stub fence

Could you move this one to dma-fence as you said? Which will be used in other place as well.

-David

On 2018年11月28日 22:50, Christian König wrote:

Extract of useful code from the timeline work. Let's use just a single stub fence instance instead of allocating a new one all the time.

Signed-off-by: Chunming Zhou david1.zhou@amd.com Signed-off-by: Christian König christian.koenig@amd.com

---

drivers/gpu/drm/drm_syncobj.c | 67 ++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 32 deletions(-)

diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index b92e3c726229..f78321338c1f 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -56,10 +56,8 @@ #include "drm_internal.h" #include <drm/drm_syncobj.h>

-struct drm_syncobj_stub_fence {

• struct dma_fence base;
• spinlock_t lock;

-}; +static DEFINE_SPINLOCK(stub_fence_lock); +static struct dma_fence stub_fence;

static const char *drm_syncobj_stub_fence_get_name(struct dma_fence *fence) { @@ -71,6 +69,25 @@ static const struct dma_fence_ops drm_syncobj_stub_fence_ops = { .get_timeline_name = drm_syncobj_stub_fence_get_name, };

+/**

• • drm_syncobj_get_stub_fence - return a signaled fence
• • Return a stub fence which is already signaled.
• */

+static struct dma_fence *drm_syncobj_get_stub_fence(void) +{

• spin_lock(&stub_fence_lock);
• if (!stub_fence.ops) {

• dma_fence_init(&stub_fence,
  

• 	       &drm_syncobj_stub_fence_ops,
  

• 	       &stub_fence_lock,
  

• 	       0, 0);
  

• dma_fence_signal_locked(&stub_fence);
  

• }
• spin_unlock(&stub_fence_lock);
• return dma_fence_get(&stub_fence);

+}

/**

• drm_syncobj_find - lookup and reference a sync object.

@@ -188,23 +205,18 @@ void drm_syncobj_replace_fence(struct drm_syncobj *syncobj, } EXPORT_SYMBOL(drm_syncobj_replace_fence);

-static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj) +/**

• • drm_syncobj_assign_null_handle - assign a stub fence to the sync object
• • @syncobj: sync object to assign the fence on
• • Assign a already signaled stub fence to the sync object.
• */

+static void drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj) {

• struct drm_syncobj_stub_fence *fence;
• fence = kzalloc(sizeof(*fence), GFP_KERNEL);
• if (fence == NULL)

• return -ENOMEM;
  

• struct dma_fence *fence = drm_syncobj_get_stub_fence();

• spin_lock_init(&fence->lock);
• dma_fence_init(&fence->base, &drm_syncobj_stub_fence_ops,

•        &fence->lock, 0, 0);
  

• dma_fence_signal(&fence->base);
• drm_syncobj_replace_fence(syncobj, &fence->base);
• dma_fence_put(&fence->base);
• return 0;

• drm_syncobj_replace_fence(syncobj, fence);

• dma_fence_put(fence); }

  /**

@@ -272,7 +284,6 @@ EXPORT_SYMBOL(drm_syncobj_free); int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags, struct dma_fence *fence) {

• int ret; struct drm_syncobj *syncobj;

  syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL);

@@ -283,13 +294,8 @@ int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags, INIT_LIST_HEAD(&syncobj->cb_list); spin_lock_init(&syncobj->lock);

• if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {

• ret = drm_syncobj_assign_null_handle(syncobj);
  

• if (ret < 0) {
  

• 	drm_syncobj_put(syncobj);
  

• 	return ret;
  

• }
  

• }

• if (flags & DRM_SYNCOBJ_CREATE_SIGNALED)

• drm_syncobj_assign_null_handle(syncobj);
  
  

  if (fence) drm_syncobj_replace_fence(syncobj, fence);

@@ -980,11 +986,8 @@ drm_syncobj_signal_ioctl(struct drm_device *dev, void *data, if (ret < 0) return ret;

• for (i = 0; i < args->count_handles; i++) {

• ret = drm_syncobj_assign_null_handle(syncobjs[i]);
  

• if (ret < 0)
  

• 	break;
  

• }

• for (i = 0; i < args->count_handles; i++)

• drm_syncobj_assign_null_handle(syncobjs[i]);
  
  

  drm_syncobj_array_free(syncobjs, args->count_handles);