From: Monk Liu <monk.liu@xxxxxxx>
there is race issue between two threads on amdgpu_bo_reference and
amdgpu_bo_import, this patch tends to fix it by moving the
pthread_mutex_lock out of bo_free_internal and move to bo_reference
to cover the update_reference part.
The mutex_unlock in bo_import should also cover bo refcount
increasement.
Change-Id: I1f65eacf74cd28cc0d3a71ef2f7a19b890d63c29
Signed-off-by: Monk Liu <monk.liu at amd.com>
---
amdgpu/amdgpu_bo.c | 5 +----
amdgpu/amdgpu_internal.h | 15 ++++++++++++---
2 files changed, 13 insertions(+), 7 deletions(-)
diff --git a/amdgpu/amdgpu_bo.c b/amdgpu/amdgpu_bo.c
index 07eb743..82f38c0 100644
--- a/amdgpu/amdgpu_bo.c
+++ b/amdgpu/amdgpu_bo.c
@@ -55,14 +55,12 @@ static void amdgpu_close_kms_handle(amdgpu_device_handle dev,
void amdgpu_bo_free_internal(amdgpu_bo_handle bo)
{
/* Remove the buffer from the hash tables. */
- pthread_mutex_lock(&bo->dev->bo_table_mutex);
util_hash_table_remove(bo->dev->bo_handles,
(void*)(uintptr_t)bo->handle);
if (bo->flink_name) {
util_hash_table_remove(bo->dev->bo_flink_names,
(void*)(uintptr_t)bo->flink_name);
}
- pthread_mutex_unlock(&bo->dev->bo_table_mutex);
/* Release CPU access. */
if (bo->cpu_map_count > 0) {
@@ -340,10 +338,9 @@ int amdgpu_bo_import(amdgpu_device_handle dev,
}
if (bo) {
- pthread_mutex_unlock(&dev->bo_table_mutex);
-
/* The buffer already exists, just bump the refcount. */
atomic_inc(&bo->refcount);
+ pthread_mutex_unlock(&dev->bo_table_mutex);
output->buf_handle = bo;
output->alloc_size = bo->alloc_size;
diff --git a/amdgpu/amdgpu_internal.h b/amdgpu/amdgpu_internal.h
index 0508131..79da0e7 100644
--- a/amdgpu/amdgpu_internal.h
+++ b/amdgpu/amdgpu_internal.h
@@ -143,7 +143,7 @@ void amdgpu_vamgr_deinit(struct amdgpu_bo_va_mgr *mgr);
uint64_t amdgpu_vamgr_find_va(struct amdgpu_bo_va_mgr *mgr, uint64_t size,
uint64_t alignment, uint64_t base_required);
-void amdgpu_vamgr_free_va(struct amdgpu_bo_va_mgr *mgr, uint64_t va,
+void amdgpu_vamgr_free_va(struct amdgpu_bo_va_mgr *mgr, uint64_t va,
uint64_t size);
int amdgpu_query_gpu_info_init(amdgpu_device_handle dev);
@@ -193,8 +193,17 @@ static inline bool update_references(atomic_t *dst, atomic_t *src)
static inline void amdgpu_bo_reference(struct amdgpu_bo **dst,
struct amdgpu_bo *src)
{
- if (update_references(&(*dst)->refcount, &src->refcount))
- amdgpu_bo_free_internal(*dst);
+ pthread_mutex_t *mlock;
+ struct amdgpu_bo* bo = *dst;
+
+ assert(bo != NULL);
+ mlock = &bo->dev->bo_table_mutex;
+ pthread_mutex_lock(mlock);
+
+ if (update_references(&bo->refcount, src?&src->refcount:NULL))
+ amdgpu_bo_free_internal(bo);
+
+ pthread_mutex_unlock(mlock);
*dst = src;
}
--
2.7.4
