fixup! test: enable trace_events tests with perfetto

Signed-off-by: Chengzhong Wu <cwu631@bloomberg.net>

Author: legendecas

.gitignore

@@ -118,7 +118,6 @@ tools/*/*.i.tmp
 
 # === Rules for tools/perfetto ===
 /tools/perfetto/trace_processor_shell
-/tools/perfetto/.version
 
 # === Rules for test artifacts ===
 /*.tap

Makefile

@@ -235,7 +235,7 @@ distclean: ## Remove all build and test artifacts.
 	$(RM) -r node_modules
 	$(RM) -r deps/icu
 	$(RM) -r deps/icu4c*.tgz deps/icu4c*.zip deps/icu-tmp
-	$(RM) tools/perfetto/trace_processor_shell tools/perfetto/.version
+	$(RM) tools/perfetto/trace_processor_shell
 	$(RM) $(BINARYTAR).* $(TARBALL).*
 
 .PHONY: check

tools/perfetto/get_trace_processor

@@ -7,12 +7,6 @@ set -e
 tools_dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
 version=$(cat "$tools_dir/../../deps/perfetto/VERSION")
 trace_processor="$1"
-stamp="$tools_dir/.version"
-
-if [ -x "$trace_processor" ] && [ "$(cat "$stamp" 2>/dev/null)" = "$version" ]; then
-  echo "trace_processor_shell v$version is already downloaded"
-  exit 0
-fi
 
 # Perfetto names its release archives <os>-<arch>, which does not match uname.
 case "$(uname -s)" in
@@ -30,10 +24,13 @@ esac
 url="https://github.com/google/perfetto/releases/download/v$version/$os-$arch.zip"
 archive="$tools_dir/$os-$arch.zip"
 
-rm -f "$trace_processor" "$stamp"
+rm -f "$trace_processor"
 echo "Downloading $url"
 curl -sSfL -o "$archive" "$url"
 unzip -q -j -o "$archive" '*/trace_processor_shell' -d "$tools_dir"
 rm -f "$archive"
 chmod +x "$trace_processor"
-printf '%s\n' "$version" > "$stamp"
+# The archive carries the release's own mtime. Make decides whether the tool is
+# current by comparing it against deps/perfetto/VERSION, so it has to come out
+# newer than the version file it was downloaded for.
+touch "$trace_processor"