[Mesa-dev] [EGL android: accquire fence implementation 1/2] i965: Return the last fence if the batch buffer is empty and nothing to be flushed when _intel_batchbuffer_flush_fence.

[Zhongmin Wu]

Always save the last fence in the brw context when flushing
buffer. If the buffer is nothing to be flushed, then return
the last fence when asked for.

Change-Id: Ic47035bcd1a27e402609afd9e2d1e3972548b97d
Signed-off-by: Zhongmin Wu <zhongmin.wu at intel.com>
---
 src/mesa/drivers/dri/i965/brw_context.c       |    5 +++++
 src/mesa/drivers/dri/i965/brw_context.h       |    1 +
 src/mesa/drivers/dri/i965/intel_batchbuffer.c |   16 ++++++++++++++--
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
index 5433f90..ed0b056 100644
--- a/src/mesa/drivers/dri/i965/brw_context.c
+++ b/src/mesa/drivers/dri/i965/brw_context.c
@@ -1086,6 +1086,8 @@ brwCreateContext(gl_api api,
    ctx->VertexProgram._MaintainTnlProgram = true;
    ctx->FragmentProgram._MaintainTexEnvProgram = true;
 
+   brw->out_fence_fd = -1;
+
    brw_draw_init( brw );
 
    if ((flags & __DRI_CTX_FLAG_DEBUG) != 0) {
@@ -1169,6 +1171,9 @@ intelDestroyContext(__DRIcontext * driContextPriv)
    brw->throttle_batch[1] = NULL;
    brw->throttle_batch[0] = NULL;
 
+   if (brw->out_fence_fd >= 0)
+      close(brw->out_fence_fd);
+
    driDestroyOptionCache(&brw->optionCache);
 
    /* free the Mesa context */
diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index dc4bc8f..692ea2c 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -1217,6 +1217,7 @@ struct brw_context
 
    __DRIcontext *driContext;
    struct intel_screen *screen;
+   int out_fence_fd;
 };
 
 /* brw_clear.c */
diff --git a/src/mesa/drivers/dri/i965/intel_batchbuffer.c b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
index 62d2fe8..d342e5d 100644
--- a/src/mesa/drivers/dri/i965/intel_batchbuffer.c
+++ b/src/mesa/drivers/dri/i965/intel_batchbuffer.c
@@ -648,9 +648,18 @@ do_flush_locked(struct brw_context *brw, int in_fence_fd, int *out_fence_fd)
          /* Add the batch itself to the end of the validation list */
          add_exec_bo(batch, batch->bo);
 
+         if (brw->out_fence_fd >= 0) {
+            close(brw->out_fence_fd);
+            brw->out_fence_fd = -1;
+         }
+
+         int fd = -1;
          ret = execbuffer(dri_screen->fd, batch, hw_ctx,
                           4 * USED_BATCH(*batch),
-                          in_fence_fd, out_fence_fd, flags);
+                          in_fence_fd, &fd, flags);
+         brw->out_fence_fd = fd;
+         if (out_fence_fd)
+            *out_fence_fd = (fd >=0) ? dup(fd) : -1;
       }
 
       throttle(brw);
@@ -684,8 +693,11 @@ _intel_batchbuffer_flush_fence(struct brw_context *brw,
 {
    int ret;
 
-   if (USED_BATCH(brw->batch) == 0)
+   if (USED_BATCH(brw->batch) == 0) {
+      if (out_fence_fd && brw->out_fence_fd >= 0)
+         *out_fence_fd = dup(brw->out_fence_fd);
       return 0;
+   }
 
    if (brw->throttle_batch[0] == NULL) {
       brw->throttle_batch[0] = brw->batch.bo;
-- 
1.7.9.5