panvk/perfetto: Handle re-submittable command buffers

Reviewed-by: Lars-Ivar Hesselberg Simonsen <lars-ivar.simonsen@arm.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36609>

src/panfrost/vulkan/panvk_utrace.c

@@ -51,6 +51,8 @@ panvk_utrace_create_buffer(struct u_trace_context *utctx, uint64_t size_B)
       .size = size_B,
    };
 
+   memset(addr_host, 0, size_B);
+
    return container;
 }
 

src/panfrost/vulkan/panvk_utrace_perfetto.cc

@@ -1,5 +1,6 @@
 /*
  * Copyright 2024 Google LLC
+ * Copyright 2025 Arm Ltd.
  * SPDX-License-Identifier: MIT
  */
 
@@ -187,6 +188,11 @@ panvk_utrace_perfetto_begin_event(struct panvk_device *dev,
    if (!ev)
       return;
 
+   struct panvk_utrace_perfetto *utp = &dev->utrace.utp;
+   if (utp->queues[data->subqueue].stack_depth == 1) {
+      utp->base_ts_ns = ts_ns;
+   }
+
    ev->begin_ns = ts_ns;
 }
 
@@ -201,6 +207,14 @@ panvk_utrace_perfetto_end_event(
    if (!ev)
       return;
 
+   struct panvk_utrace_perfetto *utp = &dev->utrace.utp;
+   if (ev->begin_ns < utp->base_ts_ns) {
+      /* The event has started before the base event of this nested stack of
+       * events. Is is likely data from a previous submission, so we just drop
+       * it here. */
+      return;
+   }
+
    PanVKRenderpassDataSource::Trace(
       [=](PanVKRenderpassDataSource::TraceContext ctx) {
          struct panvk_utrace_perfetto *utp = &dev->utrace.utp;

src/panfrost/vulkan/panvk_utrace_perfetto.h

@@ -51,6 +51,10 @@ struct panvk_utrace_perfetto {
    uint64_t next_clock_snapshot;
    uint64_t event_id;
 
+   /* Use this to reject unwritten timestamps with leftover data from previous
+    * submissions. */
+   uint64_t base_ts_ns;
+
    struct panvk_utrace_perfetto_queue queues[PANVK_UTRACE_PERFETTO_QUEUE_COUNT];
 };