Mesa (main): vulkan/wsi/x11: Use atomic_int with sent_image_count

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Module: Mesa
Branch: main
Commit: 212fb25b267120c6cc8eead21a7eb016f2b58f2a
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=212fb25b267120c6cc8eead21a7eb016f2b58f2a

Author: Jordan Justen <jordan.l.justen at intel.com>
Date:   Tue Apr 12 14:46:39 2022 -0700

vulkan/wsi/x11: Use atomic_int with sent_image_count

Without this being atomically incremented and decremented, I observed
this assert triggering in debug builds:

  src/vulkan/wsi/wsi_common_x11.c:x11_present_to_x11_dri3():

  assert(chain->sent_image_count <= chain->base.image_count);

I think this was happening since,

  src/vulkan/wsi/wsi_common_x11.c:x11_handle_dri3_present_event()

which decrements chain->sent_image_count may be run in a separate
thread.

Fixes: d0bc1ad3776 ("vulkan/wsi/x11: add sent image counter")
Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
Reviewed-by: Adam Jackson <ajax at redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15908>

---

 src/vulkan/wsi/wsi_common_x11.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/vulkan/wsi/wsi_common_x11.c b/src/vulkan/wsi/wsi_common_x11.c
index 563bf13f8c9..7dfb4c1b82d 100644
--- a/src/vulkan/wsi/wsi_common_x11.c
+++ b/src/vulkan/wsi/wsi_common_x11.c
@@ -29,6 +29,7 @@
 #include <xcb/shm.h>
 
 #include "util/macros.h"
+#include <stdatomic.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>
@@ -914,7 +915,7 @@ struct x11_swapchain {
    uint64_t                                     send_sbc;
    uint64_t                                     last_present_msc;
    uint32_t                                     stamp;
-   int                                          sent_image_count;
+   atomic_int                                   sent_image_count;
 
    bool                                         has_present_queue;
    bool                                         has_acquire_queue;