From e6fd79f3795d46dfb583e124be49fc063bc3d58b Mon Sep 17 00:00:00 2001 From: Chung-Lin Tang Date: Thu, 21 Oct 2021 21:41:21 +0800 Subject: elf: Testing infrastructure for ld.so DSO sorting (BZ #17645) This is the first of a 2-part patch set that fixes slow DSO sorting behavior in the dynamic loader, as reported in BZ #17645. In order to facilitate such a large modification to the dynamic loader, this first patch implements a testing framework for validating shared object sorting behavior, to enable comparison between old/new sorting algorithms, and any later enhancements. This testing infrastructure consists of a Python script scripts/dso-ordering-test.py' which takes in a description language, consisting of strings that describe a set of link dependency relations between DSOs, and generates testcase programs and Makefile fragments to automatically test the described situation, for example: a->b->c->d # four objects linked one after another a->[bc]->d;b->c # a depends on b and c, which both depend on d, # b depends on c (b,c linked to object a in fixed order) a->b->c;{+a;%a;-a} # a, b, c serially dependent, main program uses # dlopen/dlsym/dlclose on object a a->b->c;{}!->[abc] # a, b, c serially dependent; multiple tests generated # to test all permutations of a, b, c ordering linked # to main program (Above is just a short description of what the script can do, more documentation is in the script comments.) Two files containing several new tests, elf/dso-sort-tests-[12].def are added, including test scenarios for BZ #15311 and Redhat issue #1162810 [1]. Due to the nature of dynamic loader tests, where the sorting behavior and test output occurs before/after main(), generating testcases to use support/test-driver.c does not suffice to control meaningful timeout for ld.so. Therefore a new utility program 'support/test-run-command', based on test-driver.c/support_test_main.c has been added. This does the same testcase control, but for a program specified through a command-line rather than at the source code level. This utility is used to run the dynamic loader testcases generated by dso-ordering-test.py. [1] https://bugzilla.redhat.com/show_bug.cgi?id=1162810 Signed-off-by: Chung-Lin Tang Reviewed-by: Adhemerval Zanella --- support/Depend | 1 + support/Makefile | 6 ++++++ support/support_test_main.c | 12 ++++++++++++ support/test-driver.c | 4 +++- support/test-driver.h | 1 + support/test-run-command.c | 22 ++++++++++++++++++++++ 6 files changed, 45 insertions(+), 1 deletion(-) create mode 100644 support/Depend create mode 100644 support/test-run-command.c (limited to 'support') diff --git a/support/Depend b/support/Depend new file mode 100644 index 0000000..7e7d5dc --- /dev/null +++ b/support/Depend @@ -0,0 +1 @@ +elf diff --git a/support/Makefile b/support/Makefile index 7f03950..984ec02 100644 --- a/support/Makefile +++ b/support/Makefile @@ -257,10 +257,16 @@ others-noinstall += shell-container echo-container true-container others += $(LINKS_DSO_PROGRAM) others-noinstall += $(LINKS_DSO_PROGRAM) +others += test-run-command +others-static += test-run-command +others-noinstall += test-run-command +LDLIBS-test-run-command = $(libsupport) + $(objpfx)test-container : $(libsupport) $(objpfx)shell-container : $(libsupport) $(objpfx)echo-container : $(libsupport) $(objpfx)true-container : $(libsupport) +$(objpfx)test-run-command : $(libsupport) $(common-objpfx)elf/static-stubs.o tests = \ README-testing \ diff --git a/support/support_test_main.c b/support/support_test_main.c index 07e3cdd..66a754b 100644 --- a/support/support_test_main.c +++ b/support/support_test_main.c @@ -228,6 +228,18 @@ run_test_function (int argc, char **argv, const struct test_config *config) while (wait_for_debugger) usleep (1000); + if (config->run_command_mode) + { + /* In run-command-mode, the child process executes the command line + arguments as a new program. */ + char **argv_ = xmalloc (sizeof (char *) * argc); + memcpy (argv_, &argv[1], sizeof (char *) * (argc - 1)); + argv_[argc - 1] = NULL; + execv (argv_[0], argv_); + printf ("error: should not return here\n"); + exit (1); + } + if (config->test_function != NULL) return config->test_function (); else if (config->test_function_argv != NULL) diff --git a/support/test-driver.c b/support/test-driver.c index b0bea46..1552f62 100644 --- a/support/test-driver.c +++ b/support/test-driver.c @@ -116,7 +116,9 @@ main (int argc, char **argv) #if defined (TEST_FUNCTION) && defined (TEST_FUNCTON_ARGV) # error TEST_FUNCTION and TEST_FUNCTION_ARGV cannot be defined at the same time #endif -#if defined (TEST_FUNCTION) +#ifdef RUN_COMMAND_MODE + test_config.run_command_mode = 1; +#elif defined (TEST_FUNCTION) test_config.test_function = TEST_FUNCTION; #elif defined (TEST_FUNCTION_ARGV) test_config.test_function_argv = TEST_FUNCTION_ARGV; diff --git a/support/test-driver.h b/support/test-driver.h index 8d4f382..b44c0ff 100644 --- a/support/test-driver.h +++ b/support/test-driver.h @@ -36,6 +36,7 @@ struct test_config int expected_signal; /* If non-zero, expect termination by signal. */ char no_mallopt; /* Boolean flag to disable mallopt. */ char no_setvbuf; /* Boolean flag to disable setvbuf. */ + char run_command_mode; /* Boolean flag to indicate run-command-mode. */ const char *optstring; /* Short command line options. */ }; diff --git a/support/test-run-command.c b/support/test-run-command.c new file mode 100644 index 0000000..61560d7 --- /dev/null +++ b/support/test-run-command.c @@ -0,0 +1,22 @@ +/* Main program for test-run-command support utility. + Copyright (C) 2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +/* This is basically a configuration of test-driver.c into a general + command-line program runner. */ +#define RUN_COMMAND_MODE +#include -- cgit v1.1