[Beignet] [PATCH] Fix the multi-thread crash problem of batch buffer release.

[junyan.he at inbox.com]

From: Junyan He <junyan.he at linux.intel.com>

The case causes like this:
our thread hold the ref of the batch buffer, but have called
cl_driver_delete to delete the bufmgr. So when we release
the buffer object next time, the bufmgr's function pointer
is invalid and cause the crash.
We now release the batch buffer before every time call the
cl_set_thread_batch_buf.

Signed-off-by: Junyan He <junyan.he at linux.intel.com>
---
 src/cl_context.c   |    1 +
 src/cl_device_id.c |    2 ++
 2 files changed, 3 insertions(+)

diff --git a/src/cl_context.c b/src/cl_context.c
index 1911bf2..8190e6a 100644
--- a/src/cl_context.c
+++ b/src/cl_context.c
@@ -203,6 +203,7 @@ cl_context_delete(cl_context ctx)
   assert(ctx->buffers == NULL);
   assert(ctx->drv);
   cl_free(ctx->prop_user);
+  cl_set_thread_batch_buf(NULL);
   cl_driver_delete(ctx->drv);
   ctx->magic = CL_MAGIC_DEAD_HEADER; /* For safety */
   cl_free(ctx);
diff --git a/src/cl_device_id.c b/src/cl_device_id.c
index 7452f10..30d1639 100644
--- a/src/cl_device_id.c
+++ b/src/cl_device_id.c
@@ -24,6 +24,7 @@
 #include "cl_driver.h"
 #include "cl_device_data.h"
 #include "cl_khr_icd.h"
+#include "cl_thread.h"
 #include "CL/cl.h"
 
 #include <assert.h>
@@ -72,6 +73,7 @@ LOCAL cl_device_id
 cl_get_gt_device(void)
 {
   cl_device_id ret = NULL;
+  cl_set_thread_batch_buf(NULL);
   const int device_id = cl_driver_get_device_id();
 
 #define DECL_INFO_STRING(STRUCT, FIELD, STRING) \
-- 
1.7.9.5