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authorSamuel Thibault <samuel.thibault@ens-lyon.org>2020-02-09 20:07:51 +0000
committerSamuel Thibault <samuel.thibault@ens-lyon.org>2020-02-09 20:07:51 +0000
commitd5ec049d44f019deaeed8adc0bd10819e5569e93 (patch)
tree26b03705007a5b239c5239124f8c9381dd83001a /sysdeps/pthread/tst-rwlock16.c
parent28c30a6232aa9a54783c146590498a061fc0112a (diff)
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pthread: Move some rwlock tests from nptl to sysdeps/pthread
So they can be checked with htl too.
Diffstat (limited to 'sysdeps/pthread/tst-rwlock16.c')
-rw-r--r--sysdeps/pthread/tst-rwlock16.c182
1 files changed, 182 insertions, 0 deletions
diff --git a/sysdeps/pthread/tst-rwlock16.c b/sysdeps/pthread/tst-rwlock16.c
new file mode 100644
index 0000000000..29720c9d8d
--- /dev/null
+++ b/sysdeps/pthread/tst-rwlock16.c
@@ -0,0 +1,182 @@
+/* Copyright (C) 2015-2020 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
+   <https://www.gnu.org/licenses/>.  */
+
+/* This tests that with a reader-preferring rwlock, all readers are woken if
+   one reader "steals" lock ownership from a blocked writer.  */
+
+#include <errno.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <semaphore.h>
+#include <unistd.h>
+
+/* If we strictly prefer writers over readers, a program must not expect
+   that, in the presence of concurrent writers, one reader will also acquire
+   the lock when another reader has already done so.  Thus, use the
+   default rwlock type that does not strictly prefer writers.  */
+static pthread_rwlock_t r = PTHREAD_RWLOCK_INITIALIZER;
+
+static pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t cv = PTHREAD_COND_INITIALIZER;
+
+/* Avoid using glibc-internal atomic operations.  */
+static sem_t stop;
+static int consumer_stop = 0;
+
+static void *
+writer (void *arg)
+{
+  int s;
+
+  do
+    {
+      if (pthread_rwlock_wrlock (&r) != 0)
+	{
+	  puts ("wrlock failed");
+	  exit (EXIT_FAILURE);
+	}
+      if (pthread_rwlock_unlock (&r) != 0)
+	{
+	  puts ("unlock failed");
+	  exit (EXIT_FAILURE);
+	}
+      sem_getvalue (&stop, &s);
+    }
+  while (s == 0);
+  return NULL;
+}
+
+static void *
+reader_producer (void *arg)
+{
+  int s;
+
+  do
+    {
+      if (pthread_rwlock_rdlock (&r) != 0)
+	{
+	  puts ("rdlock reader failed");
+	  exit (EXIT_FAILURE);
+	}
+
+      sem_getvalue (&stop, &s);
+
+      pthread_mutex_lock (&m);
+      if (s != 0)
+	consumer_stop = 1;
+      pthread_cond_signal (&cv);
+      pthread_mutex_unlock (&m);
+
+      if (pthread_rwlock_unlock (&r) != 0)
+	{
+	  puts ("unlock reader failed");
+	  exit (EXIT_FAILURE);
+	}
+    }
+  while (s == 0);
+  puts ("producer finished");
+  return NULL;
+}
+
+static void *
+reader_consumer (void *arg)
+{
+  int s;
+
+  do
+    {
+      if (pthread_rwlock_rdlock (&r) != 0)
+	{
+	  puts ("rdlock reader failed");
+	  exit (EXIT_FAILURE);
+	}
+
+      pthread_mutex_lock (&m);
+      s = consumer_stop;
+      if (s == 0)
+	pthread_cond_wait (&cv, &m);
+      pthread_mutex_unlock (&m);
+
+      if (pthread_rwlock_unlock (&r) != 0)
+	{
+	  puts ("unlock reader failed");
+	  exit (EXIT_FAILURE);
+	}
+    }
+  while (s == 0);
+    puts ("consumer finished");
+  return NULL;
+}
+
+
+static int
+do_test (void)
+{
+  pthread_t w1, w2, rp, rc;
+
+  if (pthread_create (&w1, NULL, writer, NULL) != 0)
+    {
+      puts ("create failed");
+      return 1;
+    }
+  if (pthread_create (&w2, NULL, writer, NULL) != 0)
+    {
+      puts ("create failed");
+      return 1;
+    }
+  if (pthread_create (&rc, NULL, reader_consumer, NULL) != 0)
+    {
+      puts ("create failed");
+      return 1;
+    }
+  if (pthread_create (&rp, NULL, reader_producer, NULL) != 0)
+    {
+      puts ("create failed");
+      return 1;
+    }
+
+  sleep (2);
+  sem_post (&stop);
+
+  if (pthread_join (w1, NULL) != 0)
+    {
+      puts ("w1 join failed");
+      return 1;
+    }
+  if (pthread_join (w2, NULL) != 0)
+    {
+      puts ("w2 join failed");
+      return 1;
+    }
+  if (pthread_join (rp, NULL) != 0)
+    {
+      puts ("reader_producer join failed");
+      return 1;
+    }
+  if (pthread_join (rc, NULL) != 0)
+    {
+      puts ("reader_consumer join failed");
+      return 1;
+    }
+
+  return 0;
+}
+
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"