iris: drop cache coherent cpu mapping for external BO
We have to assume any external buffer could be used by the display HW.
In the case that buffer is also CPU mapped, we want to assume no cache
coherency as it is only available between GT & CPU, not display.
Many thanks to Michel Dänzer for the hint!
v2: Move cache coherent drop to bufmgr (Chris)
v3: Also make BO external if created with PIPE_BIND_SHARED (Eric)
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: <mesa-stable@lists.freedesktop.org>
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/2552
Reviewed-by: Eric Anholt <eric@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4533>
diff --git a/src/gallium/drivers/iris/iris_bufmgr.c b/src/gallium/drivers/iris/iris_bufmgr.c
index ca8db31..c333f7b 100644
--- a/src/gallium/drivers/iris/iris_bufmgr.c
+++ b/src/gallium/drivers/iris/iris_bufmgr.c
@@ -1376,12 +1376,17 @@
{
if (!bo->external) {
_mesa_hash_table_insert(bo->bufmgr->handle_table, &bo->gem_handle, bo);
+ /* If a BO is going to be used externally, it could be sent to the
+ * display HW. So make sure our CPU mappings don't assume cache
+ * coherency since display is outside that cache.
+ */
+ bo->cache_coherent = false;
bo->external = true;
bo->reusable = false;
}
}
-static void
+void
iris_bo_make_external(struct iris_bo *bo)
{
struct iris_bufmgr *bufmgr = bo->bufmgr;
diff --git a/src/gallium/drivers/iris/iris_bufmgr.h b/src/gallium/drivers/iris/iris_bufmgr.h
index caeba61..6f4bcbf 100644
--- a/src/gallium/drivers/iris/iris_bufmgr.h
+++ b/src/gallium/drivers/iris/iris_bufmgr.h
@@ -310,6 +310,13 @@
int iris_bo_flink(struct iris_bo *bo, uint32_t *name);
/**
+ * Make a BO externally accessible.
+ *
+ * \param bo Buffer to make external
+ */
+void iris_bo_make_external(struct iris_bo *bo);
+
+/**
* Returns 1 if mapping the buffer for write could cause the process
* to block, due to the object being active in the GPU.
*/
diff --git a/src/gallium/drivers/iris/iris_resource.c b/src/gallium/drivers/iris/iris_resource.c
index 40655bb..3476809 100644
--- a/src/gallium/drivers/iris/iris_resource.c
+++ b/src/gallium/drivers/iris/iris_resource.c
@@ -801,6 +801,9 @@
return NULL;
}
+ if (templ->bind & PIPE_BIND_SHARED)
+ iris_bo_make_external(res->bo);
+
return &res->base;
}
@@ -924,6 +927,9 @@
map_aux_addresses(screen, res);
}
+ if (templ->bind & PIPE_BIND_SHARED)
+ iris_bo_make_external(res->bo);
+
return &res->base;
fail:
