gn/perfetto.gni

# Copyright (C) 2017 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import("//build_overrides/build.gni")
import("wasm_vars.gni")

# Summary of our typical build configurations:

# 1. Standalone builds
#    build_with_chromium = false
#    is_perfetto_build_generator = false
#    perfetto_build_standalone = true
#    perfetto_build_with_android = false
#    perfetto_build_with_embedder = false

# 2. Android tree builds
#    build_with_chromium = false
#    is_perfetto_build_generator = true
#    perfetto_build_standalone = false
#    perfetto_build_with_android = true
#    perfetto_build_with_embedder = false

# 3. Chromium tree builds
#    build_with_chromium = true
#    is_perfetto_build_generator = false
#    perfetto_build_standalone = false
#    perfetto_build_with_android = false
#    perfetto_build_with_embedder = true

# 4. Builds in other embedder trees (e.g. V8 standalone)
#    build_with_chromium = false
#    is_perfetto_build_generator = false
#    perfetto_build_standalone = false
#    perfetto_build_with_android = false
#    perfetto_build_with_embedder = true

# 5. Amalgamated sources (Client library)
#    build_with_chromium = false
#    is_perfetto_build_generator = true
#    perfetto_build_standalone = false
#    perfetto_build_with_android = false
#    perfetto_build_with_embedder = true

# +----------------------------------------------------------------------------+
# | Toolchain / environment related configuration                              |
# +----------------------------------------------------------------------------+
# This section contains a bunch of variables that are related with the toolchain
# and the build environment. Only tools/gen_xxx should customize them.

# Note that |build_with_chromium| is a global convention used by several
# projects, set outside of our control.

# Chromium sets this to true in its //build_overrides/build.gni.
if (!defined(build_with_chromium)) {
  build_with_chromium = false
}

declare_args() {
  # The Android blueprint file generator set this to true (as well as
  # is_perfetto_build_generator). This is just about being built in the
  # Android tree (AOSP and internal) and is NOT related with the target OS.
  # In standalone Android builds and Chromium Android builds, this is false.
  perfetto_build_with_android = false

  # All the tools/gen_* scripts set this to true. This is mainly used to locate
  # .gni files from //gn rather than //build.
  is_perfetto_build_generator = false

  # This is for override via `gn args` (e.g. for tools/gen_xxx). Embedders
  # based on GN (e.g. v8) should NOT set this and instead directly sets
  # perfetto_build_with_embedder=true in their GN files.
  is_perfetto_embedder = false
}

# This can be overridden by embedders (e.g. v8) in their .gn(i) files. This must
# be different from the GN args flag (is_perfetto_embedder) because of the way
# GN works.
if (!defined(perfetto_build_with_embedder)) {
  perfetto_build_with_embedder = build_with_chromium || is_perfetto_embedder
}

perfetto_build_standalone =
    !perfetto_build_with_android && !build_with_chromium &&
    !perfetto_build_with_embedder

# Only relevant for GN builds. Sets the path where perfetto lives. This is //
# for standalone builds and //third_party/perfetto/ in embedders. The embedder
# can ovverride it in its GN files.
if (perfetto_build_standalone || is_perfetto_build_generator) {
  perfetto_root_path = "//"
  import("//gn/standalone/android.gni")  # For android_api_level
  import("//gn/standalone/sanitizers/vars.gni")  # For is_fuzzer
} else if (!defined(perfetto_root_path)) {
  perfetto_root_path = "//third_party/perfetto/"
  import("//build/config/android/config.gni")  # For android_api_level
}

# Whether the ftrace producer and the service should be started
# by the integration test or assumed to be running.
# If we're building in the Android tree, we expect that the testing infra
# will start the binaries in the system image before the tests are run.
# In all other cases (i.e. when true), a temporary in-process instance will be
# brought up by our own integrationtest harness.
start_daemons_for_testing = !perfetto_build_with_android

# +----------------------------------------------------------------------------+
# | Tunable build variables for embedders                                      |
# +----------------------------------------------------------------------------+
# The variables in this section allow embedders to enable/disable features
# at the build-system level. This allows to opt-in into the various services
# and tools.

perfetto_force_dlog_default = ""
if (build_with_chromium) {
  perfetto_force_dlog_default = "off"
}

declare_args() {
  # Platform-wide tracing executables (traced, traced_probes, perfetto_cmd).
  enable_perfetto_platform_services =
      perfetto_build_standalone || perfetto_build_with_android

  # Allow the embedder to use the IPC layer. In turn this allows to use the
  # system backend in the client library.
  # This includes building things that rely on POSIX sockets, this places
  # limitations on the supported operating systems.
  enable_perfetto_ipc = (is_android || is_linux || is_mac) &&
                        (perfetto_build_standalone ||
                         perfetto_build_with_android || build_with_chromium)

  # Makes the heap profiling daemon target reachable. It works only on Android,
  # but is built on Linux as well for test/compiler coverage.
  # On Android, it requires API level 26 due to libunwindstack.
  enable_perfetto_heapprofd =
      perfetto_build_with_android ||
      (perfetto_build_standalone && is_clang &&
       (is_linux || (is_android && android_api_level >= 26)))

  # The Trace Processor: offline analytical engine to process traces and compute
  # metrics using a SQL engine.
  enable_perfetto_trace_processor =
      perfetto_build_standalone || build_with_chromium ||
      is_perfetto_build_generator

  # Enables base::Watchdog. Is supported only on Linux-based platforms.
  # gn/BUILD.gn further restricts this to OS_LINUX || OS_ANDROID when generating
  # the perfetto_build_flags.h header.
  enable_perfetto_watchdog =
      perfetto_build_with_android || perfetto_build_standalone

  # Misc host executable under tools/.
  enable_perfetto_tools =
      (perfetto_build_standalone && current_toolchain == host_toolchain) ||
      perfetto_build_with_android

  # Allows to build the UI (TypeScript/ HTML / WASM)
  enable_perfetto_ui = perfetto_build_standalone

  enable_perfetto_unittests = perfetto_build_standalone ||
                              build_with_chromium || perfetto_build_with_android

  enable_perfetto_integration_tests =
      perfetto_build_standalone || perfetto_build_with_android

  enable_perfetto_benchmarks = perfetto_build_standalone

  enable_perfetto_fuzzers =
      perfetto_build_standalone && defined(is_fuzzer) && is_fuzzer

  # Enables the gen_git_revision tool that generates a .h that contains a macro
  # with the current git revision. Works only in standalone GN checkouts.
  # If disabled, the version string will be "unknown".
  enable_perfetto_version_gen =
      perfetto_build_standalone && !is_perfetto_build_generator

  # Only for local development. When true the binaries (perfetto, traced, ...)
  # are monolithic and don't use a common shared library. This is mainly to
  # avoid LD_LIBRARY_PATH dances when testing locally.
  monolithic_binaries = false

  # Whether DLOG should be enabled on debug builds (""), all builds ("on"), or
  # none ("off"). We disable it by default for embedders to avoid spamming their
  # console.
  perfetto_force_dlog = perfetto_force_dlog_default
}

declare_args() {
  enable_perfetto_trace_processor_sqlite = enable_perfetto_trace_processor

  # Enables the optional SQLite percentile module.
  enable_perfetto_trace_processor_percentile =
      enable_perfetto_trace_processor && perfetto_build_standalone

  # Enables JSON support in the trace processor.
  enable_perfetto_trace_processor_json =
      enable_perfetto_trace_processor && !perfetto_build_with_android

  # Enables the REPL interactive prompt in the trace processor.
  enable_perfetto_trace_processor_linenoise =
      perfetto_build_standalone && enable_perfetto_trace_processor &&
      (is_linux || is_android || is_mac)
}

# +---------------------------------------------------------------------------+
# | Cross-checks                                                              |
# +---------------------------------------------------------------------------+

# Exactly one between build_with_android, build_standalone and
# build_with_embedder must be true.
assert(perfetto_build_standalone || perfetto_build_with_android ||
       perfetto_build_with_embedder)
assert(!(perfetto_build_with_android && perfetto_build_standalone))
assert(!(perfetto_build_with_embedder && perfetto_build_standalone))
assert(!(perfetto_build_with_android && perfetto_build_with_embedder))

# If |build_with_chromium| is true then also |perfetto_build_with_embedder|
# must be true
assert(!build_with_chromium || perfetto_build_with_embedder)

# If |perfetto_build_with_android| is true then also
# |is_perfetto_build_generator| must be true.
assert(!perfetto_build_with_android || is_perfetto_build_generator)

# The IPC layer based on UNIX sockets can't be built on Win.
assert(!enable_perfetto_ipc || !is_win)

# We should never end up in a state where is_perfetto_embedder=true but
# perfetto_build_with_embedder=false.
assert(!is_perfetto_embedder || perfetto_build_with_embedder)

# The monolithic binaries is not supported when building in the Android tree.
assert(!monolithic_binaries || !perfetto_build_with_android)

# Watchdog must be on in Android builds.
assert(enable_perfetto_watchdog || !perfetto_build_with_android)

assert(perfetto_force_dlog == "" || perfetto_force_dlog == "on" ||
       perfetto_force_dlog == "off")