test-lib: add a SANITIZE=leak logging mode

Add the ability to run the test suite under a new
"GIT_TEST_SANITIZE_LEAK_LOG=true" mode, when true we'll log the leaks
we find an a new "test-results/<test-name>.leak" directory.

That new path is consistent with the existing
"test-results/<test-name>.<type>" results, except that those are all
files, not directories.

We also set "log_exe_name=1" to include the name of the executable in
the filename. This gives us files like "trace.git.<pid>" instead of
the default of "trace.<pid>". I.e. we'll be able to distinguish "git"
leaks from "test-tool", "git-daemon" etc.

We then set "dedup_token_length" to non-zero ("0" is the default) to
succinctly log a token we can de-duplicate these stacktraces on. The
string is simply a one-line stack-trace with only function names up to
N frames, which we limit at "9999" as a shorthand for
"infinite" (there appears to be no way to say "no limit").

With these combined we can now easily get e.g. the top 10 leaks in the
test suite grouped by full stacktrace:

    grep -o -P -h '(?<=DEDUP_TOKEN: ).*' test-results/*.leak/trace.git.* | sort | uniq -c | sort -nr | head -n 10

Or add "grep -E -o '[^-]+'" to that to group by functions instead of
stack traces:

    grep -o -P -h '(?<=DEDUP_TOKEN: ).*' test-results/*.leak/trace.git.* | grep -E -o '[^-]+' | sort | uniq -c | sort -nr | head -n 20

This new mode requires git to be compiled with SANITIZE=leak, rather
than explaining that in the documentation let's make it
self-documenting by bailing out if the user asks for this without git
having been compiled with SANITIZE=leak, as we do with
GIT_TEST_PASSING_SANITIZE_LEAK=true.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
maint
Ævar Arnfjörð Bjarmason 2022-07-28 01:13:34 +02:00 committed by Junio C Hamano
parent ac8e3e94e5
commit 366bd129dc
2 changed files with 34 additions and 1 deletions

View File

@ -371,6 +371,11 @@ declared themselves as leak-free by setting
"TEST_PASSES_SANITIZE_LEAK=true" before sourcing "test-lib.sh". This
test mode is used by the "linux-leaks" CI target.

GIT_TEST_SANITIZE_LEAK_LOG=true will log memory leaks to
"test-results/$TEST_NAME.leak/trace.*" files. The logs include a
"dedup_token" (see +"ASAN_OPTIONS=help=1 ./git") and other options to
make logs +machine-readable.

GIT_TEST_PROTOCOL_VERSION=<n>, when set, makes 'protocol.version'
default to n.


View File

@ -305,6 +305,10 @@ TEST_NUMBER="${TEST_NAME%%-*}"
TEST_NUMBER="${TEST_NUMBER#t}"
TEST_RESULTS_DIR="$TEST_OUTPUT_DIRECTORY/test-results"
TEST_RESULTS_BASE="$TEST_RESULTS_DIR/$TEST_NAME$TEST_STRESS_JOB_SFX"
TEST_RESULTS_SAN_FILE_PFX=trace
TEST_RESULTS_SAN_DIR_SFX=leak
TEST_RESULTS_SAN_FILE=
TEST_RESULTS_SAN_DIR="$TEST_RESULTS_DIR/$TEST_NAME.$TEST_RESULTS_SAN_DIR_SFX"
TRASH_DIRECTORY="trash directory.$TEST_NAME$TEST_STRESS_JOB_SFX"
test -n "$root" && TRASH_DIRECTORY="$root/$TRASH_DIRECTORY"
case "$TRASH_DIRECTORY" in
@ -1447,6 +1451,10 @@ then
test_done
fi

BAIL_OUT_ENV_NEEDS_SANITIZE_LEAK () {
BAIL_OUT "$1 has no effect except when compiled with SANITIZE=leak"
}

if test -n "$SANITIZE_LEAK"
then
if test_bool_env GIT_TEST_PASSING_SANITIZE_LEAK false
@ -1461,9 +1469,29 @@ then
test_done
fi
fi

if test_bool_env GIT_TEST_SANITIZE_LEAK_LOG false
then
if ! mkdir -p "$TEST_RESULTS_SAN_DIR"
then
BAIL_OUT "cannot create $TEST_RESULTS_SAN_DIR"
fi &&
TEST_RESULTS_SAN_FILE="$TEST_RESULTS_SAN_DIR/$TEST_RESULTS_SAN_FILE_PFX"

# Don't litter *.leak dirs if there was nothing to report
test_atexit "rmdir \"$TEST_RESULTS_SAN_DIR\" 2>/dev/null || :"

prepend_var LSAN_OPTIONS : dedup_token_length=9999
prepend_var LSAN_OPTIONS : log_exe_name=1
prepend_var LSAN_OPTIONS : log_path=\"$TEST_RESULTS_SAN_FILE\"
export LSAN_OPTIONS
fi
elif test_bool_env GIT_TEST_PASSING_SANITIZE_LEAK false
then
BAIL_OUT "GIT_TEST_PASSING_SANITIZE_LEAK=true has no effect except when compiled with SANITIZE=leak"
BAIL_OUT_ENV_NEEDS_SANITIZE_LEAK "GIT_TEST_PASSING_SANITIZE_LEAK=true"
elif test_bool_env GIT_TEST_SANITIZE_LEAK_LOG false
then
BAIL_OUT_ENV_NEEDS_SANITIZE_LEAK "GIT_TEST_SANITIZE_LEAK_LOG=true"
fi

# Last-minute variable setup