[Mesa-dev] [PATCH] vulkan/wsi/x11: Destroy Present event context when destroying swapchain

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

Without this, the X server may accumulate stale Present event contexts
if a client creates and destroys multiple swapchains using the same
window.

v2: Based on Chris Wilson's review:
* Use xcb_present_select_input_checked so that protocol errors
  generated by old X servers can be handled gracefully
* Use xcb_discard_reply() instead of free(xcb_request_check())
v3: Rebased on top of this code having been refactored out of anv

Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---

Now tested to compile and run Dota 2 with radv.

 src/vulkan/wsi/wsi_common_x11.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/vulkan/wsi/wsi_common_x11.c b/src/vulkan/wsi/wsi_common_x11.c
index 8e0043f..56398ce 100644
--- a/src/vulkan/wsi/wsi_common_x11.c
+++ b/src/vulkan/wsi/wsi_common_x11.c
@@ -891,6 +891,8 @@ x11_swapchain_destroy(struct wsi_swapchain *anv_chain,
                       const VkAllocationCallbacks *pAllocator)
 {
    struct x11_swapchain *chain = (struct x11_swapchain *)anv_chain;
+   xcb_void_cookie_t cookie;
+
    for (uint32_t i = 0; i < chain->image_count; i++)
       x11_image_finish(chain, pAllocator, &chain->images[i]);
 
@@ -904,6 +906,10 @@ x11_swapchain_destroy(struct wsi_swapchain *anv_chain,
    }
 
    xcb_unregister_for_special_event(chain->conn, chain->special_event);
+   cookie = xcb_present_select_input_checked(chain->conn, chain->event_id,
+                                             chain->window,
+                                             XCB_PRESENT_EVENT_MASK_NO_EVENT);
+   xcb_discard_reply(chain->conn, cookie.sequence);
 
    vk_free(pAllocator, chain);
 
-- 
2.10.2