[2.25 COMMITTED] nptl: Add tst-minstack-cancel, tst-minstack-exit [BZ #22636]

[fweimer@redhat.com (Florian Weimer)]

I verified that without the guard accounting change in commit
630f4cc3aa019ede55976ea561f1a7af2f068639 (Fix stack guard size
accounting) and RTLD_NOW for libgcc_s introduced by commit
f993b8754080ac7572b692870e926d8b493db16c (nptl: Open libgcc.so with
RTLD_NOW during pthread_cancel), the tst-minstack-cancel test fails on
an AVX-512F machine.  tst-minstack-exit still passes, and either of
the mentioned commit by itself frees sufficient stack space to make
tst-minstack-cancel pass, too.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit d8b778907e5270fdeb70459842ffbc20bd2ca5e1)

2018-01-11  Florian Weimer  <fweimer@redhat.com>

	[BZ #22636]
	* nptl/Makefile (tests): Add tst-minstack-cancel, tst-minstack-exit.
	* nptl/tst-minstack-cancel.c, nptl/tst-minstack-exit.c: New files.

diff --git a/nptl/Makefile b/nptl/Makefile
index 4a0d027fa2..8bcb346866 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -300,7 +300,7 @@ tests = tst-typesizes \
 	tst-bad-schedattr \
 	tst-thread_local1 tst-mutex-errorcheck tst-robust10 \
 	tst-robust-fork tst-create-detached \
-	tst-thread-exit-clobber
+	tst-thread-exit-clobber tst-minstack-cancel tst-minstack-exit
 
 xtests = tst-setuid1 tst-setuid1-static tst-setuid2 \
 	tst-mutexpp1 tst-mutexpp6 tst-mutexpp10
diff --git a/nptl/tst-minstack-cancel.c b/nptl/tst-minstack-cancel.c
new file mode 100644
index 0000000000..a306320e88
--- /dev/null
+++ b/nptl/tst-minstack-cancel.c
@@ -0,0 +1,48 @@
+/* Test cancellation with a minimal stack size.
+   Copyright (C) 2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+/* Note: This test is similar to tst-minstack-exit, but is separate to
+   avoid spurious test passes due to warm-up effects.  */
+
+#include <limits.h>
+#include <unistd.h>
+#include <support/check.h>
+#include <support/xthread.h>
+
+static void *
+threadfunc (void *closure)
+{
+  while (1)
+    pause ();
+  return NULL;
+}
+
+static int
+do_test (void)
+{
+  pthread_attr_t attr;
+  xpthread_attr_init (&attr);
+  xpthread_attr_setstacksize (&attr, PTHREAD_STACK_MIN);
+  pthread_t thr = xpthread_create (&attr, threadfunc, NULL);
+  xpthread_cancel (thr);
+  TEST_VERIFY (xpthread_join (thr) == PTHREAD_CANCELED);
+  xpthread_attr_destroy (&attr);
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/nptl/tst-minstack-exit.c b/nptl/tst-minstack-exit.c
new file mode 100644
index 0000000000..9c7e9a4dfe
--- /dev/null
+++ b/nptl/tst-minstack-exit.c
@@ -0,0 +1,46 @@
+/* Test that pthread_exit works with the minimum stack size.
+   Copyright (C) 2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+/* Note: This test is similar to tst-minstack-cancel, but is separate
+   to avoid spurious test passes due to warm-up effects.  */
+
+#include <limits.h>
+#include <unistd.h>
+#include <support/check.h>
+#include <support/xthread.h>
+
+static void *
+threadfunc (void *closure)
+{
+  pthread_exit (threadfunc);
+  return NULL;
+}
+
+static int
+do_test (void)
+{
+  pthread_attr_t attr;
+  xpthread_attr_init (&attr);
+  xpthread_attr_setstacksize (&attr, PTHREAD_STACK_MIN);
+  pthread_t thr = xpthread_create (&attr, threadfunc, NULL);
+  TEST_VERIFY (xpthread_join (thr) == threadfunc);
+  xpthread_attr_destroy (&attr);
+  return 0;
+}
+
+#include <support/test-driver.c>