[PATCH] perf buildid-cache: Add test for PE executable

From: Nicholas Fraser
Date: Thu Feb 18 2021 - 13:24:03 EST


This builds on the previous changes to tests/shell/buildid.sh, adding
tests for a PE file. It adds it to the build-id cache manually and, if
Wine is available, runs it under "perf record" and verifies that it was
added automatically.

If wine is not installed, only warnings are printed; the test can still
exit 0.

Signed-off-by: Nicholas Fraser <nfraser@xxxxxxxxxxxxxxx>
---
tools/perf/tests/shell/buildid.sh | 65 +++++++++++++++++++++++++++----
1 file changed, 58 insertions(+), 7 deletions(-)

diff --git a/tools/perf/tests/shell/buildid.sh b/tools/perf/tests/shell/buildid.sh
index 416af614bbe0..f05670d1e39e 100755
--- a/tools/perf/tests/shell/buildid.sh
+++ b/tools/perf/tests/shell/buildid.sh
@@ -14,18 +14,56 @@ if ! [ -x "$(command -v cc)" ]; then
exit 2
fi

+# check what we need to test windows binaries
+add_pe=1
+run_pe=1
+if ! perf version --build-options | grep -q 'libbfd: .* on '; then
+ echo "WARNING: perf not built with libbfd. PE binaries will not be tested."
+ add_pe=0
+ run_pe=0
+fi
+if ! which wine > /dev/null; then
+ echo "WARNING: wine not found. PE binaries will not be run."
+ run_pe=0
+fi
+
+# set up wine
+if [ ${run_pe} -eq 1 ]; then
+ wineprefix=$(mktemp -d /tmp/perf.wineprefix.XXX)
+ export WINEPREFIX=${wineprefix}
+ # clear display variables to prevent wine from popping up dialogs
+ unset DISPLAY
+ unset WAYLAND_DISPLAY
+fi
+
ex_md5=$(mktemp /tmp/perf.ex.MD5.XXX)
ex_sha1=$(mktemp /tmp/perf.ex.SHA1.XXX)
+ex_pe=$(dirname $0)/../pe-file.exe

echo 'int main(void) { return 0; }' | cc -Wl,--build-id=sha1 -o ${ex_sha1} -x c -
echo 'int main(void) { return 0; }' | cc -Wl,--build-id=md5 -o ${ex_md5} -x c -

-echo "test binaries: ${ex_sha1} ${ex_md5}"
+echo "test binaries: ${ex_sha1} ${ex_md5} ${ex_pe}"

check()
{
- id=`readelf -n ${1} 2>/dev/null | grep 'Build ID' | awk '{print $3}'`
-
+ case $1 in
+ *.exe)
+ # We don't have a tool that can pull a nicely formatted build-id out of
+ # a PE file, but we can extract the whole section with objcopy and
+ # format it ourselves. The .buildid section is a Debug Directory
+ # containing a CodeView entry:
+ # https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#debug-directory-image-only
+ # https://github.com/dotnet/runtime/blob/da94c022576a5c3bbc0e896f006565905eb137f9/docs/design/specs/PE-COFF.md
+ # The build-id starts at byte 33 and must be rearranged into a GUID.
+ id=`objcopy -O binary --only-section=.buildid $1 /dev/stdout | \
+ cut -c 33-48 | hexdump -ve '/1 "%02x"' | \
+ sed 's@^\(..\)\(..\)\(..\)\(..\)\(..\)\(..\)\(..\)\(..\)\(.*\)0a$@\4\3\2\1\6\5\8\7\9@'`
+ ;;
+ *)
+ id=`readelf -n ${1} 2>/dev/null | grep 'Build ID' | awk '{print $3}'`
+ ;;
+ esac
echo "build id: ${id}"

link=${build_id_dir}/.build-id/${id:0:2}/${id:2}
@@ -50,7 +88,7 @@ check()
exit 1
fi

- ${perf} buildid-cache -l | grep $id
+ ${perf} buildid-cache -l | grep ${id}
if [ $? -ne 0 ]; then
echo "failed: ${id} is not reported by \"perf buildid-cache -l\""
exit 1
@@ -79,16 +117,20 @@ test_record()
{
data=$(mktemp /tmp/perf.data.XXX)
build_id_dir=$(mktemp -d /tmp/perf.debug.XXX)
+ log=$(mktemp /tmp/perf.log.XXX)
perf="perf --buildid-dir ${build_id_dir}"

- ${perf} record --buildid-all -o ${data} ${1}
+ echo "running: perf record $@"
+ ${perf} record --buildid-all -o ${data} $@ &> ${log}
if [ $? -ne 0 ]; then
- echo "failed: record ${1}"
+ echo "failed: record $@"
+ echo "see log: ${log}"
exit 1
fi

- check ${1}
+ check ${@: -1}

+ rm -f ${log}
rm -rf ${build_id_dir}
rm -rf ${data}
}
@@ -96,12 +138,21 @@ test_record()
# add binaries manual via perf buildid-cache -a
test_add ${ex_sha1}
test_add ${ex_md5}
+if [ ${add_pe} -eq 1 ]; then
+ test_add ${ex_pe}
+fi

# add binaries via perf record post processing
test_record ${ex_sha1}
test_record ${ex_md5}
+if [ ${run_pe} -eq 1 ]; then
+ test_record wine ${ex_pe}
+fi

# cleanup
rm ${ex_sha1} ${ex_md5}
+if [ ${run_pe} -eq 1 ]; then
+ rm -r ${wineprefix}
+fi

exit ${err}
--
2.30.1