Mesa (main): zink: rework choose_pdev to (finally) be competent

[GitLab Mirror]

Module: Mesa
Branch: main
Commit: c3ad1331be6939aadb8365d995778f797c0db5ab
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=c3ad1331be6939aadb8365d995778f797c0db5ab

Author: Mike Blumenkrantz <michael.blumenkrantz at gmail.com>
Date:   Mon Apr 11 11:04:45 2022 -0400

zink: rework choose_pdev to (finally) be competent

now zink will init using a priority system if multiple devices are available

multiple devices will ONLY be available if:
* the user does not specify VK_ICD_FILENAMES as they should
* the user does not specify LIBGL_ALWAYS_SOFTWARE
* multiple drivers exist

I've prioritized the virtualized gpu here with the assumption that if
such a thing is detected, the environment is most likely virtualized

Reviewed-by: Yonggang Luo <luoyonggang at gmail.com>
Reviewed-by: Dave Airlie <airlied at redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15857>

---

 src/gallium/drivers/zink/zink_screen.c | 56 ++++++++++++++++++++++++----------
 1 file changed, 40 insertions(+), 16 deletions(-)

diff --git a/src/gallium/drivers/zink/zink_screen.c b/src/gallium/drivers/zink/zink_screen.c
index ca7a6635ecb..04a58facf1c 100644
--- a/src/gallium/drivers/zink/zink_screen.c
+++ b/src/gallium/drivers/zink/zink_screen.c
@@ -1279,30 +1279,52 @@ choose_pdev(struct zink_screen *screen)
    assert(result == VK_SUCCESS);
    assert(pdev_count > 0);
 
-   VkPhysicalDeviceProperties *props = &screen->info.props;
+   VkPhysicalDeviceProperties props;
    bool cpu = debug_get_bool_option("LIBGL_ALWAYS_SOFTWARE", false);
+   /* priority when multiple drivers are available (highest to lowest):
+      VK_PHYSICAL_DEVICE_TYPE_VIRTUAL_GPU
+      VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU
+      VK_PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU
+      VK_PHYSICAL_DEVICE_TYPE_CPU
+      VK_PHYSICAL_DEVICE_TYPE_OTHER
+
+    * users should specify VK_ICD_FILENAMES since this is a standardized variable
+    * used by all vulkan applications
+    */
+   unsigned prio_map[] = {
+      [VK_PHYSICAL_DEVICE_TYPE_OTHER] = 0,
+      [VK_PHYSICAL_DEVICE_TYPE_CPU] = 1,
+      [VK_PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU] = 2,
+      [VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU] = 3,
+      [VK_PHYSICAL_DEVICE_TYPE_VIRTUAL_GPU] = 4,
+   };
+   unsigned idx = 0;
+   int cur_prio = 0;
    for (i = 0; i < pdev_count; ++i) {
-      vkGetPhysicalDeviceProperties(pdevs[i], props);
+      vkGetPhysicalDeviceProperties(pdevs[i], &props);
 
       if (cpu) {
-         if (props->deviceType == VK_PHYSICAL_DEVICE_TYPE_CPU) {
-            screen->pdev = pdevs[i];
-            screen->info.device_version = props->apiVersion;
-            is_cpu = true;
+         /* if user wants cpu, only give them cpu */
+         if (props.deviceType == VK_PHYSICAL_DEVICE_TYPE_CPU) {
+            idx = i;
+            cur_prio = prio_map[props.deviceType];
             break;
          }
-         continue;
-      }
-
-      if (props->deviceType != VK_PHYSICAL_DEVICE_TYPE_CPU) {
-         screen->pdev = pdevs[i];
-         screen->info.device_version = props->apiVersion;
-         break;
+      } else {
+         assert(props.deviceType <= VK_PHYSICAL_DEVICE_TYPE_CPU);
+         if (prio_map[props.deviceType] > cur_prio) {
+            idx = i;
+            cur_prio = prio_map[props.deviceType];
+         }
       }
    }
-   free(pdevs);
-   if (cpu && !screen->pdev)
-      return true;
+   is_cpu = cur_prio == prio_map[VK_PHYSICAL_DEVICE_TYPE_CPU];
+   if (cpu && !is_cpu)
+      goto out;
+
+   screen->pdev = pdevs[idx];
+   vkGetPhysicalDeviceProperties(screen->pdev, &screen->info.props);
+   screen->info.device_version = screen->info.props.apiVersion;
 
    /* runtime version is the lesser of the instance version and device version */
    screen->vk_version = MIN2(screen->info.device_version, screen->instance_info.loader_version);
@@ -1314,6 +1336,8 @@ choose_pdev(struct zink_screen *screen)
       screen->spirv_version = SPIRV_VERSION(1, 3);
    else
       screen->spirv_version = SPIRV_VERSION(1, 0);
+out:
+   free(pdevs);
    return is_cpu;
 }