[PATCH v8 2/3] perf tests: avoid storing an absolute path in perf binary

From: Denys Zagorui
Date: Mon May 24 2021 - 07:15:30 EST


python binding test uses PYTHONPATH definition to find python/perf.so
library. This definition is an absolute path that makes perf binary
unreproducible. This path can be found during runtime execution.

Signed-off-by: Denys Zagorui <dzagorui@xxxxxxxxx>
---
tools/perf/tests/Build | 2 +-
tools/perf/tests/python-use.c | 25 ++++++++++++++++++++++---
2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index 650aec19d490..a20098dcdbc4 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -98,5 +98,5 @@ perf-$(CONFIG_DWARF_UNWIND) += dwarf-unwind.o
endif

CFLAGS_attr.o += -DBINDIR="BUILD_STR($(bindir_SQ))" -DPYTHON="BUILD_STR($(PYTHON_WORD))"
-CFLAGS_python-use.o += -DPYTHONPATH="BUILD_STR($(OUTPUT)python)" -DPYTHON="BUILD_STR($(PYTHON_WORD))"
+CFLAGS_python-use.o += -DPYTHON="BUILD_STR($(PYTHON_WORD))"
CFLAGS_dwarf-unwind.o += -fno-optimize-sibling-calls
diff --git a/tools/perf/tests/python-use.c b/tools/perf/tests/python-use.c
index 98c6d474aa6f..32af71300aa3 100644
--- a/tools/perf/tests/python-use.c
+++ b/tools/perf/tests/python-use.c
@@ -8,18 +8,37 @@
#include <linux/compiler.h>
#include "tests.h"
#include "util/debug.h"
+#include "util/util.h"
+#include <sys/stat.h>
+#include <limits.h>
+#include <libgen.h>

int test__python_use(struct test *test __maybe_unused, int subtest __maybe_unused)
{
char *cmd;
- int ret;
+ int ret = -1;
+ char *exec_path;
+ char buf[PATH_MAX];
+ char *pythonpath;
+ struct stat sb;
+
+ perf_exe(buf, PATH_MAX);
+ exec_path = dirname(buf);
+
+ if (asprintf(&pythonpath, "%s/python", exec_path) < 0)
+ return ret;
+
+ if (stat(pythonpath, &sb) || !S_ISDIR(sb.st_mode))
+ pythonpath[0] = 0;

if (asprintf(&cmd, "echo \"import sys ; sys.path.append('%s'); import perf\" | %s %s",
- PYTHONPATH, PYTHON, verbose > 0 ? "" : "2> /dev/null") < 0)
- return -1;
+ pythonpath, PYTHON, verbose > 0 ? "" : "2> /dev/null") < 0)
+ goto out;

pr_debug("python usage test: \"%s\"\n", cmd);
ret = system(cmd) ? -1 : 0;
free(cmd);
+out:
+ free(pythonpath);
return ret;
}
--
2.26.2.Cisco