Vulkan: release command buffer memory at each begin on Arm's driver (memory leak)

docs/vulkan-gpu-defaults.md

@@ -15,6 +15,7 @@ Vendor IDs: 0x13B5 Arm (Mali), 0x5143 Qualcomm (Adreno), 0x8086 Intel, 0x1002 AM
 | Structured shaders (static branch stacks, no jump loop) | Mali, Adreno | PanVK (RK3588), Turnip | #562 | `LARECOMP_VK_STRUCTURE` |
 | c1 inlined, hot constant buffer words as push constants | Mali, Adreno | PanVK; Turnip (Adreno 643) | #563, #579 | `LARECOMP_VK_PUSH_CB`, `LARECOMP_VK_INLINE_C1` |
 | Split pass barriers | Mali | PanVK | | `LARECOMP_VK_SPLIT_BARRIER` |
+| Command buffers release their memory at each begin (a memory leak without it) | Arm's driver (not PanVK) | libmali g29p1 (Mali-G610, RK3588) | | `LARECOMP_VK_CB_RELEASE` |
 | Branch stacks as variables instead of arrays | Intel | | #462 | `LARECOMP_VK_STACK_ARRAYS=1` gives arrays |
 | Placeholder colour attachment for depth-only passes | Intel | UHD 630 on Windows (a driver crash without it, #8, #46) | | `LARECOMP_VK_PLACEHOLDER_COLOR` |
 | Guest heap as driver memory | RADV, PanVK | PanVK (Mali-G610), RADV | #564, #483 | `LARECOMP_VK_HEAP_DMABUF` |

runtime/nvn/vulkan/device.c

@@ -693,6 +693,12 @@ static void create_device(void) {
         // issue #483: an 81-minute run without faults, the Field 15 -> 21 fps, ~85% fewer uploads). PanVK's device name
         // is the GPU's ("Mali-G610 MC4"), hence the driver ID.
         g_vk.heap_dmabuf_default = strstr(g_vk.props.deviceName, "RADV") != NULL || drv.driverID == VK_DRIVER_ID_MESA_PANVK;
+        // command buffers released before each begin (record.c begin_cb_run) by default on Arm's own driver: the implicit
+        // reset of vkBeginCommandBuffer keeps the memory vkCmdBeginRendering allocates (64 KB blocks of host memory), so
+        // the process grew by ~490 MB an hour, until it ran out of memory (libmali g29p1 on RK3588; PanVK and Turnip don't).
+        const char *cbr = getenv("LARECOMP_VK_CB_RELEASE");
+        g_vk.cb_release = cbr ? atoi(cbr) != 0 : drv.driverID == VK_DRIVER_ID_ARM_PROPRIETARY;
+        if (g_vk.cb_release) LOG("[vk] command buffers release their memory at each begin%s\n", cbr ? " (LARECOMP_VK_CB_RELEASE)" : ": Arm's driver");
 #ifdef VK_EXT_graphics_pipeline_library
         if (gpl_ext)
             snprintf(gpl, sizeof gpl, "%s (fast linking %s, independent interpolation decoration %s)",

runtime/nvn/vulkan/record.c

@@ -534,8 +534,11 @@ void rec_UpdateDescriptorSets(uint32_t n, const VkWriteDescriptorSet *w) {
 
 // ================================================================== command buffers, submissions, presents
 static void begin_cb_run(const void *p) {
+    VkCommandBuffer cb = *(const VkCommandBuffer *)p;
+    // (g_vk.cb_release, device.c: Arm's driver keeps vkCmdBeginRendering's memory across the implicit reset below)
+    if (g_vk.cb_release) VK_CHECK(vkResetCommandBuffer(cb, VK_COMMAND_BUFFER_RESET_RELEASE_RESOURCES_BIT));
     VkCommandBufferBeginInfo bi = {.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO, .flags = VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT};
-    VK_CHECK(vkBeginCommandBuffer(*(const VkCommandBuffer *)p, &bi));
+    VK_CHECK(vkBeginCommandBuffer(cb, &bi));
 }
 void rec_BeginCommandBuffer(VkCommandBuffer cb) {
     if (on <= 0) { begin_cb_run(&cb); return; }

runtime/nvn/vulkan/vk.h

@@ -44,6 +44,7 @@ typedef struct {
     bool gpl_probe;
     bool map_placed, unmap_reserve;  // VK_EXT_map_memory_placed: driver memory mapped at a given address (exec.c guest_heap_dmabuf)
     bool heap_dmabuf_default;  // the heap as driver memory by default: RADV and Mesa's PanVK (device.c; LARECOMP_VK_HEAP_DMABUF overrides)
+    bool cb_release;  // command buffers reset with RELEASE_RESOURCES before each begin: Arm's driver (device.c; LARECOMP_VK_CB_RELEASE)
     bool ssbo_chunks;  // stores and atomics from fragment and vertex shaders (exec.c: the heap in chunks counts misses)
     bool lazy_heap, bda;  // the heap imported chunk by chunk (device.c lazy_heap_predicted), buffer device addresses enabled for it
     bool heap_probe;      // one import tried at the start, lazy chunks if it runs out of memory (exec.c whole_import_probe_oom)