[Mesa-dev] [PATCH 2/3] st/nine: Fix Multithreading issue with MANAGED buffers

[Axel Davy]

d3d calls are protected by mutexes, however if app is doing in
two threads:

Thread 1: buffer Lock
Thread 2: Draw call
Thread 1: writes data
Thread 1: Unlock

Then before this patch, the Draw call would begin to upload
the buffer.

Solves this by moving the moment we add the buffer to the queue
of things to upload (We move it from Lock time to Unlock time).

Cc: "11.2" <mesa-stable at lists.freedesktop.org>

Signed-off-by: Axel Davy <axel.davy at ens.fr>
---
 src/gallium/state_trackers/nine/buffer9.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/gallium/state_trackers/nine/buffer9.c b/src/gallium/state_trackers/nine/buffer9.c
index 8efb4ce..6d5d9d6 100644
--- a/src/gallium/state_trackers/nine/buffer9.c
+++ b/src/gallium/state_trackers/nine/buffer9.c
@@ -178,7 +178,6 @@ NineBuffer9_Lock( struct NineBuffer9 *This,
         if (!(Flags & D3DLOCK_READONLY)) {
             if (!This->managed.dirty) {
                 assert(LIST_IS_EMPTY(&This->managed.list));
-                list_add(&This->managed.list, &This->base.base.device->update_buffers);
                 This->managed.dirty = TRUE;
                 This->managed.dirty_box = box;
             } else {
@@ -232,8 +231,13 @@ NineBuffer9_Unlock( struct NineBuffer9 *This )
     user_assert(This->nmaps > 0, D3DERR_INVALIDCALL);
     if (This->base.pool != D3DPOOL_MANAGED)
         This->pipe->transfer_unmap(This->pipe, This->maps[--(This->nmaps)]);
-    else
+    else {
         This->nmaps--;
+        /* TODO: Fix this to upload at the first draw call needing the data,
+         * instead of at the next draw call */
+        if (!This->nmaps && This->managed.dirty && LIST_IS_EMPTY(&This->managed.list))
+            list_add(&This->managed.list, &This->base.base.device->update_buffers);
+    }
     return D3D_OK;
 }
 
-- 
2.7.1