netris-nestri/build/patches/mesa/0002-radv-amdgpu-query-all-three-heaps-with-one-AMDGPU_IN.patch

From ef1f613123fadfd8ef778f77090ba696cb18797e Mon Sep 17 00:00:00 2001
From: DatCaptainHorse <DatCaptainHorse@users.noreply.github.com>
Date: Thu, 17 Sep 2026 19:33:08 +0300
Subject: [PATCH] radv/amdgpu: query all three heaps with one
 AMDGPU_INFO_MEMORY

radv_amdgpu_winsys_query_heap_info() wants the usage of VRAM, visible VRAM
and GTT. It called ac_drm_query_heap_info() three times to get them, which
is six ioctls: each of those calls also re-queries the device's static
VRAM_GTT sizes, and then only .heap_usage is used out of the result.

AMDGPU_INFO_MEMORY returns all three heaps together, each with its usage,
which is exactly what this function assembles. One query replaces six.

Six ioctls instead of one is invisible on a local device and is not
invisible over virtio, where each is a synchronous round trip to the host.
Measured on an amdgpu native context with one game running, this function
alone accounted for 94% of all guest-to-host traffic -- around 300 round
trips per frame, against 20 for the actual command submissions -- and with
it most of the frame time.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
---
 .../vulkan/winsys/amdgpu/radv_amdgpu_winsys.c | 36 +++++++++++--------
 1 file changed, 21 insertions(+), 15 deletions(-)

diff --git a/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_winsys.c b/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_winsys.c
index 6aaf8a475c3..a7587f86d85 100644
--- a/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_winsys.c
+++ b/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_winsys.c
@@ -378,7 +378,7 @@ fail:
 int
 radv_amdgpu_winsys_query_heap_info(ac_drm_device *dev, struct radeon_winsys_heap_info *heap_info)
 {
-   struct amdgpu_heap_info heap_vram = {0}, heap_vram_vis = {0}, heap_gtt = {0};
+   struct drm_amdgpu_memory_info mem_info = {0};
    struct radv_amdgpu_alloc_tracker *alloc_tracker;
    int r;
 
@@ -393,20 +393,26 @@ radv_amdgpu_winsys_query_heap_info(ac_drm_device *dev, struct radeon_winsys_heap
    heap_info->allocated_vram_vis = alloc_tracker->allocated_vram_vis;
    heap_info->allocated_gtt = alloc_tracker->allocated_gtt;
 
-   /* VRAM usage. */
-   r = ac_drm_query_heap_info(dev, AMDGPU_GEM_DOMAIN_VRAM, 0, &heap_vram);
-   if (!r)
-      heap_info->vram_usage = heap_vram.heap_usage;
-
-   /* VRAM visible usage. */
-   r = ac_drm_query_heap_info(dev, AMDGPU_GEM_DOMAIN_VRAM, AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED, &heap_vram_vis);
-   if (!r)
-      heap_info->vram_vis_usage = heap_vram_vis.heap_usage;
-
-   /* GTT usage. */
-   r = ac_drm_query_heap_info(dev, AMDGPU_GEM_DOMAIN_GTT, 0, &heap_gtt);
-   if (!r)
-      heap_info->gtt_usage = heap_gtt.heap_usage;
+   /* One query for all three heaps.
+    *
+    * AMDGPU_INFO_MEMORY returns vram, cpu_accessible_vram and gtt together,
+    * each with its usage -- which is the whole of what this function wants.
+    * Three ac_drm_query_heap_info() calls did the same work in six ioctls,
+    * because each of them also re-queried the device's static VRAM_GTT sizes
+    * and then used only .heap_usage out of the result.
+    *
+    * Six ioctls instead of one is invisible on a local device and is not
+    * invisible over virtio, where each is a synchronous round trip to the
+    * host. Measured on an amdgpu native context with one game running, this
+    * function alone accounted for 94% of all guest-to-host traffic and most of
+    * the frame time.
+    */
+   r = ac_drm_query_info(dev, AMDGPU_INFO_MEMORY, sizeof(mem_info), &mem_info);
+   if (!r) {
+      heap_info->vram_usage = mem_info.vram.heap_usage;
+      heap_info->vram_vis_usage = mem_info.cpu_accessible_vram.heap_usage;
+      heap_info->gtt_usage = mem_info.gtt.heap_usage;
+   }
 
    radv_amdgpu_alloc_tracker_release(alloc_tracker);