Add perfetto tracing to host tooling

Example cvd create trace:
https://ui.perfetto.dev/#!/?s=315a987bda469405966eb46797201e11b12d247c

Example cvd fetch trace:
https://ui.perfetto.dev/#!/?s=8e6e182ffab8e92f0f0a690b205c73313ec71f17

Perfetto uses a shared memory buffer between producer processes and the
traced consumer daemon. `fork()` is problematic for this as the parent
and child processes would end up clobbering each other when the shared
memory buffer is inherited by the child. To prevent this, we introduce
a perfetto wrapper that uses `pthread_atfork()` to register handlers that
shutdown and restart tracing before and after forking.

Perfetto also depends on global static data and explicitly calls out that
it can not be restarted unless this data is cleared [1]. With this, the
Perfetto wrapper utilizes `dlopen()` and `dlclose()` during init and
shutdown.

Perfetto also uses thread local data which requires extra care around
`dlclose()` to prevent some thread local destructors from running after
`dlclose()` has already unloaded the Perfetto library. To work around
this, the Perfetto wrapper isolates all Perfetto calls into a single
worker thread.

[1] https://github.com/google/perfetto/blob/ab21398d658ce3bccc192b226d2731add6c02890/include/perfetto/tracing/tracing.h#L252

Bug: b/378560215

Author: jmacnak

base/cvd/MODULE.bazel

@@ -37,6 +37,7 @@ bazel_dep(name = "nasm", version = "2.16.03.bcr.1")
 bazel_dep(name = "pcre2", version = "10.45")
 bazel_dep(name = "platforms", version = "1.0.0")
 bazel_dep(name = "protobuf", version = "31.1")
+bazel_dep(name = "re2")
 bazel_dep(name = "rootcanal")
 bazel_dep(name = "rules_cc", version = "0.2.16")
 bazel_dep(name = "rules_flex", version = "0.4")

base/cvd/build_external/build_external.MODULE.bazel

@@ -48,6 +48,7 @@ include("//build_external/mkbootimg:mkbootimg.MODULE.bazel")
 include("//build_external/ms-tpm-20-ref:ms-tpm-20-ref.MODULE.bazel")
 include("//build_external/mtools:mtools.MODULE.bazel")
 include("//build_external/opengl_headers:opengl_headers.MODULE.bazel")
+include("//build_external/perfetto:perfetto.MODULE.bazel")
 include("//build_external/pyyaml:pyyaml.MODULE.bazel")
 include("//build_external/re2:re2.MODULE.bazel")
 include("//build_external/rootcanal:rootcanal.MODULE.bazel")

base/cvd/build_external/perfetto/BUILD

@@ -0,0 +1,49 @@
+From 45c2b6299505b133fdce117649f457e36640d824 Mon Sep 17 00:00:00 2001
+From: Jason Macnak <natsu@google.com>
+Date: Fri, 15 May 2026 11:28:54 -0700
+Subject: [PATCH 1/4] Disable Android components to avoid extra dependencies
+
+---
+ bazel/rules.bzl | 8 +++-----
+ 1 file changed, 3 insertions(+), 5 deletions(-)
+
+diff --git a/bazel/rules.bzl b/bazel/rules.bzl
+index 6195465a67..a3e367cde8 100644
+--- a/bazel/rules.bzl
++++ b/bazel/rules.bzl
+@@ -13,9 +13,7 @@
+ # limitations under the License.
+ 
+ load("@perfetto//bazel:proto_gen.bzl", "proto_descriptor_gen", "proto_gen")
+-load("@perfetto//bazel:run_ait_with_adb.bzl", "android_instrumentation_test")
+ load("@perfetto_cfg//:perfetto_cfg.bzl", "PERFETTO_CONFIG")
+-load("@rules_android//android:rules.bzl", "android_binary", "android_library")
+ 
+ # +----------------------------------------------------------------------------+
+ # | Base C++ rules.                                                            |
+@@ -113,11 +111,11 @@ def perfetto_jspb_proto_library(**kwargs):
+ # +----------------------------------------------------------------------------+
+ def perfetto_android_binary(**kwargs):
+     if not _rule_override("android_binary", **kwargs):
+-        android_binary(**kwargs)
++        return
+ 
+ def perfetto_android_library(**kwargs):
+     if not _rule_override("android_library", **kwargs):
+-        android_library(**kwargs)
++        return
+ 
+ def perfetto_android_jni_library(**kwargs):
+     if not _rule_override("android_jni_library", **kwargs):
+@@ -171,7 +169,7 @@ def _perfetto_android_jni_library(
+ 
+ def perfetto_android_instrumentation_test(**kwargs):
+     if not _rule_override("android_instrumentation_test", **kwargs):
+-        android_instrumentation_test(**kwargs)
++        return
+ 
+ # +----------------------------------------------------------------------------+
+ # | Misc rules.                                                                |
+-- 
+2.54.0.563.g4f69b47b94-goog
+

base/cvd/build_external/perfetto/PATCH.0001_disable_android_deps.patch

@@ -0,0 +1,131 @@
+From 5e991031fa757ade8a7be54e5bfab69ec627a432 Mon Sep 17 00:00:00 2001
+From: Jason Macnak <natsu@google.com>
+Date: Fri, 15 May 2026 11:29:26 -0700
+Subject: [PATCH 2/4] Add load statements for Bazel 9
+
+---
+ bazel/proto_gen.bzl |  2 ++
+ bazel/rules.bzl     | 30 ++++++++++++++++++------------
+ 2 files changed, 20 insertions(+), 12 deletions(-)
+
+diff --git a/bazel/proto_gen.bzl b/bazel/proto_gen.bzl
+index 74f91cad89..1764cb2d9a 100644
+--- a/bazel/proto_gen.bzl
++++ b/bazel/proto_gen.bzl
+@@ -15,6 +15,8 @@
+ # This file defines the proto_gen() rule that is used for generating protos
+ # with custom plugins (ipc and protozero).
+ 
++load("@protobuf//bazel/common:proto_info.bzl", "ProtoInfo")
++
+ def _proto_gen_impl(ctx):
+     proto_src = [
+         f
+diff --git a/bazel/rules.bzl b/bazel/rules.bzl
+index a3e367cde8..15f6d52d5b 100644
+--- a/bazel/rules.bzl
++++ b/bazel/rules.bzl
+@@ -14,6 +14,12 @@
+ 
+ load("@perfetto//bazel:proto_gen.bzl", "proto_descriptor_gen", "proto_gen")
+ load("@perfetto_cfg//:perfetto_cfg.bzl", "PERFETTO_CONFIG")
++load("@protobuf//bazel:cc_proto_library.bzl", "cc_proto_library")
++load("@protobuf//bazel:proto_library.bzl", "proto_library")
++load("@protobuf//bazel:java_lite_proto_library.bzl", "java_lite_proto_library")
++load("@rules_cc//cc:cc_binary.bzl", "cc_binary")
++load("@rules_cc//cc:cc_library.bzl", "cc_library")
++load("@rules_python//python:defs.bzl", "py_binary", "py_library")
+ 
+ # +----------------------------------------------------------------------------+
+ # | Base C++ rules.                                                            |
+@@ -38,7 +44,7 @@ def default_cc_args():
+ 
+ def perfetto_build_config_cc_library(**kwargs):
+     if not _rule_override("cc_library", **kwargs):
+-        native.cc_library(**kwargs)
++        cc_library(**kwargs)
+ 
+ def perfetto_filegroup(**kwargs):
+     if not _rule_override("filegroup", **kwargs):
+@@ -51,20 +57,20 @@ def perfetto_genrule(**kwargs):
+ def perfetto_cc_library(**kwargs):
+     args = _merge_dicts(default_cc_args(), kwargs)
+     if not _rule_override("cc_library", **args):
+-        native.cc_library(**args)
++        cc_library(**args)
+ 
+ def perfetto_cc_binary(**kwargs):
+     args = _merge_dicts(default_cc_args(), kwargs)
+     if not _rule_override("cc_binary", **args):
+-        native.cc_binary(**args)
++        cc_binary(**args)
+ 
+ def perfetto_py_binary(**kwargs):
+     if not _rule_override("py_binary", **kwargs):
+-        native.py_binary(**kwargs)
++        py_binary(**kwargs)
+ 
+ def perfetto_py_library(**kwargs):
+     if not _rule_override("py_library", **kwargs):
+-        native.py_library(**kwargs)
++        py_library(**kwargs)
+ 
+ # +----------------------------------------------------------------------------+
+ # | Proto-related rules                                                        |
+@@ -72,11 +78,11 @@ def perfetto_py_library(**kwargs):
+ 
+ def perfetto_proto_library(**kwargs):
+     if not _rule_override("proto_library", **kwargs):
+-        native.proto_library(**kwargs)
++        proto_library(**kwargs)
+ 
+ def perfetto_cc_proto_library(**kwargs):
+     if not _rule_override("cc_proto_library", **kwargs):
+-        native.cc_proto_library(**kwargs)
++        cc_proto_library(**kwargs)
+ 
+ def perfetto_java_proto_library(**kwargs):
+     if not _rule_override("java_proto_library", **kwargs):
+@@ -84,7 +90,7 @@ def perfetto_java_proto_library(**kwargs):
+ 
+ def perfetto_java_lite_proto_library(**kwargs):
+     if not _rule_override("java_lite_proto_library", **kwargs):
+-        native.java_lite_proto_library(**kwargs)
++        java_lite_proto_library(**kwargs)
+ 
+ # Unlike the other rules, this is an noop by default because Bazel does not
+ # support Go proto libraries.
+@@ -142,7 +148,7 @@ def _perfetto_android_jni_library(
+     if not (binary_name.startswith("lib") and binary_name.endswith(".so")):
+         fail("'binary_name' should sharts with 'lib' and ends with '.so'" +
+              ", got %s instead" % binary_name)
+-    # We strip the name, since `native.cc_binary` adds prefix and suffix
++    # We strip the name, since `cc_binary` adds prefix and suffix
+     # to the generated library name.
+     binary_target_name = binary_name.removeprefix("lib").removesuffix(".so")
+     input_cc_library_name = name + "_input"
+@@ -150,18 +156,18 @@ def _perfetto_android_jni_library(
+     # exclude them from being build when invoke `bazel build :all`,
+     # since these targets won't be able to compile anyway, see
+     # https://bazel.build/docs/android-ndk#cclibrary-android.
+-    native.cc_library(
++    cc_library(
+         name = input_cc_library_name,
+         target_compatible_with = ["@platforms//os:android"],
+         **input_cc_library_kwargs
+     )
+-    native.cc_binary(
++    cc_binary(
+         name = binary_target_name,
+         linkshared = True,
+         deps = [input_cc_library_name],
+         target_compatible_with = ["@platforms//os:android"],
+     )
+-    native.cc_library(
++    cc_library(
+         name = name,
+         srcs = [binary_target_name],
+         target_compatible_with = ["@platforms//os:android"],
+-- 
+2.54.0.563.g4f69b47b94-goog
+

base/cvd/build_external/perfetto/PATCH.0002_add_load_statements.patch

@@ -0,0 +1,39 @@
+From 8ae64deaf5cb13bcdfb87d576b6d207a2fef13df Mon Sep 17 00:00:00 2001
+From: Jason Macnak <natsu@google.com>
+Date: Fri, 15 May 2026 11:33:40 -0700
+Subject: [PATCH 3/4] Expose shutdown in perfetto_c
+
+---
+ include/perfetto/public/abi/producer_abi.h | 3 +++
+ src/shared_lib/producer.cc                 | 4 ++++
+ 2 files changed, 7 insertions(+)
+
+diff --git a/include/perfetto/public/abi/producer_abi.h b/include/perfetto/public/abi/producer_abi.h
+index 8899d0098e..e43da137c5 100644
+--- a/include/perfetto/public/abi/producer_abi.h
++++ b/include/perfetto/public/abi/producer_abi.h
+@@ -79,6 +79,9 @@ PERFETTO_SDK_EXPORT void PerfettoProducerActivateTriggers(
+     const char* trigger_names[],
+     uint32_t ttl_ms);
+ 
++
++PERFETTO_SDK_EXPORT void PerfettoProducerShutdown(void);
++
+ #ifdef __cplusplus
+ }
+ #endif
+diff --git a/src/shared_lib/producer.cc b/src/shared_lib/producer.cc
+index 06599f97e1..8f90bedb2d 100644
+--- a/src/shared_lib/producer.cc
++++ b/src/shared_lib/producer.cc
+@@ -81,3 +81,7 @@ void PerfettoProducerActivateTriggers(const char* trigger_names[],
+   }
+   perfetto::Tracing::ActivateTriggers(triggers, ttl_ms);
+ }
++
++void PerfettoProducerShutdown(void) {
++  perfetto::Tracing::Shutdown();
++}
+-- 
+2.54.0.563.g4f69b47b94-goog
+

base/cvd/build_external/perfetto/PATCH.0003_expose_shutdown.patch

@@ -0,0 +1,54 @@
+From 3c24b5504feba80a1f48c22cf4bfaf27733aee34 Mon Sep 17 00:00:00 2001
+From: Jason Macnak <natsu@google.com>
+Date: Fri, 15 May 2026 11:37:20 -0700
+Subject: [PATCH 4/4] Expose flush in libperfetto_c
+
+---
+ include/perfetto/public/abi/track_event_abi.h | 2 ++
+ src/shared_lib/track_event/ds.h               | 4 ++++
+ src/shared_lib/track_event/track_event.cc     | 4 ++++
+ 3 files changed, 10 insertions(+)
+
+diff --git a/include/perfetto/public/abi/track_event_abi.h b/include/perfetto/public/abi/track_event_abi.h
+index 6c07b30bd4..5c315ea942 100644
+--- a/include/perfetto/public/abi/track_event_abi.h
++++ b/include/perfetto/public/abi/track_event_abi.h
+@@ -145,6 +145,8 @@ enum PerfettoTeType {
+   PERFETTO_TE_TYPE_COUNTER = 4,
+ };
+
++PERFETTO_SDK_EXPORT void PerfettoTeFlush(void);
++
+ #ifdef __cplusplus
+ }
+ #endif
+diff --git a/src/shared_lib/track_event/ds.h b/src/shared_lib/track_event/ds.h
+index 199a1e3d6a..be13a0593b 100644
+--- a/src/shared_lib/track_event/ds.h
++++ b/src/shared_lib/track_event/ds.h
+@@ -127,6 +127,10 @@ class TrackEvent
+     Register(dsd);
+   }
+
++  static void Flush() {
++    TrackEvent::Trace([](TrackEvent::TraceContext ctx) { ctx.Flush(); });
++  }
++
+   static void UpdateDescriptorFromCategories(DataSourceDescriptor dsd) {
+     dsd.set_name("track_event");
+     UpdateDescriptor(dsd);
+diff --git a/src/shared_lib/track_event/track_event.cc b/src/shared_lib/track_event/track_event.cc
+index b6f9000ad3..70dd68d61b 100644
+--- a/src/shared_lib/track_event/track_event.cc
++++ b/src/shared_lib/track_event/track_event.cc
+@@ -86,3 +86,7 @@ void PerfettoTeCategoryImplDestroy(struct PerfettoTeCategoryImpl* cat) {
+   perfetto::shlib::GlobalState::Instance().UnregisterCategory(cat);
+   delete cat;
+ }
++
++void PerfettoTeFlush(void) {
++  perfetto::shlib::TrackEvent::Flush();
++}
+--
+2.54.0.563.g4f69b47b94-goog
+

base/cvd/build_external/perfetto/PATCH.0004_expose_flush.patch

@@ -0,0 +1,3 @@
+perfetto_ext = use_extension("//build_external/perfetto:repositories.bzl", "perfetto_extension")
+use_repo(perfetto_ext, "perfetto")
+use_repo(perfetto_ext, "perfetto_cfg")

base/cvd/build_external/perfetto/perfetto.MODULE.bazel

@@ -0,0 +1,32 @@
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+# https://github.com/google/perfetto/issues/2787 for Perfetto getting into the
+# Central Repository.
+def _perfetto_extension_impl(_):
+    # From commit 877553985565ab10fe20ea844891aacabd0f70c7:
+    URL = "https://github.com/google/perfetto/archive/refs/tags/v55.2.tar.gz"
+    http_archive(
+        name = "perfetto",
+        url = URL,
+        strip_prefix = "perfetto-55.2",
+        patch_args = ["-p1"],
+        patches = [
+            "@//build_external/perfetto:PATCH.0001_disable_android_deps.patch",
+            "@//build_external/perfetto:PATCH.0002_add_load_statements.patch",
+            "@//build_external/perfetto:PATCH.0003_expose_shutdown.patch",
+            "@//build_external/perfetto:PATCH.0004_expose_flush.patch",
+        ],
+    )
+    http_archive(
+        name = "perfetto_cfg",
+        url = URL,
+        strip_prefix = "perfetto-55.2/bazel/standalone",
+        build_file_content = "# empty BUILD to make a bazel package",
+        patch_cmds = [
+            "sed -i 's|@com_google_protobuf|@protobuf|g' perfetto_cfg.bzl",
+        ],
+    )
+
+perfetto_extension = module_extension(
+    implementation = _perfetto_extension_impl,
+)

base/cvd/build_external/perfetto/repositories.bzl

@@ -72,6 +72,7 @@ cf_cc_binary(
         "//cuttlefish/host/libs/config/fastboot",
         "//cuttlefish/host/libs/feature:inject",
         "//cuttlefish/host/libs/log_names",
+        "//cuttlefish/host/libs/tracing",
         "//cuttlefish/posix:symlink",
         "//cuttlefish/pretty:vector",
         "//libbase",
@@ -169,6 +170,7 @@ cf_cc_library(
         "//cuttlefish/common/libs/utils:subprocess",
         "//cuttlefish/common/libs/utils:subprocess_managed_stdio",
         "//cuttlefish/host/libs/config:config_utils",
+        "//cuttlefish/host/libs/tracing",
         "//cuttlefish/posix:strerror",
         "//cuttlefish/result",
         "//libbase",
@@ -223,6 +225,7 @@ cf_cc_library(
         "//cuttlefish/host/libs/config:file_source",
         "//cuttlefish/host/libs/config:instance_nums",
         "//cuttlefish/host/libs/feature:inject",
+        "//cuttlefish/host/libs/tracing",
         "//cuttlefish/result",
         "//libbase",
         "@abseil-cpp//absl/log",
@@ -240,6 +243,7 @@ cf_cc_library(
         "//cuttlefish/host/libs/config:vmm_mode",
         "//cuttlefish/host/libs/image_aggregator",
         "//cuttlefish/host/libs/image_aggregator:qcow2",
+        "//cuttlefish/host/libs/tracing",
         "//cuttlefish/result",
         "//libbase",
         "@abseil-cpp//absl/log",
@@ -357,6 +361,7 @@ cf_cc_library(
         "//cuttlefish/host/libs/config:secure_hals",
         "//cuttlefish/host/libs/config:vmm_mode",
         "//cuttlefish/host/libs/config/defaults",
+        "//cuttlefish/host/libs/tracing",
         "//cuttlefish/host/libs/vhal_proxy_server",
         "//cuttlefish/host/libs/vm_manager",
         "//cuttlefish/result",
@@ -405,6 +410,7 @@ cf_cc_library(
         "//cuttlefish/host/libs/config:config_utils",
         "//cuttlefish/host/libs/config:display",
         "//cuttlefish/host/libs/config:gpu_mode",
+        "//cuttlefish/host/libs/tracing",
         "//cuttlefish/pretty",
         "//cuttlefish/pretty:optional",
         "//cuttlefish/pretty:string",
@@ -434,6 +440,7 @@ cf_cc_library(
         "//cuttlefish/host/libs/config:guest_hwui_renderer",
         "//cuttlefish/host/libs/config:guest_renderer_preload",
         "//cuttlefish/host/libs/config:vmm_mode",
+        "//cuttlefish/host/libs/tracing",
         "//cuttlefish/result",
         "//libbase",
         "@abseil-cpp//absl/log",