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-rw-r--r--samples/hung_task/hung_task_mutex.c66
1 files changed, 0 insertions, 66 deletions
diff --git a/samples/hung_task/hung_task_mutex.c b/samples/hung_task/hung_task_mutex.c
deleted file mode 100644
index 47ed38239ea3..000000000000
--- a/samples/hung_task/hung_task_mutex.c
+++ /dev/null
@@ -1,66 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * hung_task_mutex.c - Sample code which causes hung task by mutex
- *
- * Usage: load this module and read `<debugfs>/hung_task/mutex`
- * by 2 or more processes.
- *
- * This is for testing kernel hung_task error message.
- * Note that this will make your system freeze and maybe
- * cause panic. So do not use this except for the test.
- */
-
-#include <linux/debugfs.h>
-#include <linux/delay.h>
-#include <linux/fs.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-
-#define HUNG_TASK_DIR "hung_task"
-#define HUNG_TASK_FILE "mutex"
-#define SLEEP_SECOND 256
-
-static const char dummy_string[] = "This is a dummy string.";
-static DEFINE_MUTEX(dummy_mutex);
-static struct dentry *hung_task_dir;
-
-static ssize_t read_dummy(struct file *file, char __user *user_buf,
- size_t count, loff_t *ppos)
-{
- /* If the second task waits on the lock, it is uninterruptible sleep. */
- guard(mutex)(&dummy_mutex);
-
- /* When the first task sleep here, it is interruptible. */
- msleep_interruptible(SLEEP_SECOND * 1000);
-
- return simple_read_from_buffer(user_buf, count, ppos,
- dummy_string, sizeof(dummy_string));
-}
-
-static const struct file_operations hung_task_fops = {
- .read = read_dummy,
-};
-
-static int __init hung_task_sample_init(void)
-{
- hung_task_dir = debugfs_create_dir(HUNG_TASK_DIR, NULL);
- if (IS_ERR(hung_task_dir))
- return PTR_ERR(hung_task_dir);
-
- debugfs_create_file(HUNG_TASK_FILE, 0400, hung_task_dir,
- NULL, &hung_task_fops);
-
- return 0;
-}
-
-static void __exit hung_task_sample_exit(void)
-{
- debugfs_remove_recursive(hung_task_dir);
-}
-
-module_init(hung_task_sample_init);
-module_exit(hung_task_sample_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Masami Hiramatsu");
-MODULE_DESCRIPTION("Simple sleep under mutex file for testing hung task");