[Mod] 支持Mutex 死锁测试

arch/arm64/configs/lubancat2_defconfig

@@ -800,3 +800,5 @@ CONFIG_BLK_DEV_IO_TRACE=y
 CONFIG_LKDTM=y
 
 CONFIG_TESTING_PSTORE=m
+CONFIG_LOCK_STAT=y
+CONFIG_PROVE_LOCKING=y

gaoyang3513/testings/pstore/test_ps.c

@@ -4,6 +4,8 @@
 #include <linux/delay.h>
 #include <linux/vmalloc.h>
 #include <linux/rcupdate.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
 
 static unsigned int test_type;
 module_param(test_type, uint, 0400);
@@ -61,6 +63,56 @@ static void trigger_rcu(void)
     call_rcu(&test_rcu_head, bad_rcu_callback);
 }
 
+static int is_ready_thread1, is_ready_thread2;
+static struct task_struct *thread1;
+static struct task_struct *thread2;
+
+static DEFINE_MUTEX(mutex_a);
+static DEFINE_MUTEX(mutex_b);
+
+static int thread_func(void *data)
+{
+    char *name = (char *) data;
+
+    if (!strcmp(name, "Thread1")) {
+        printk(KERN_INFO "%s: Acquiring mutex A...\n", name);
+        mutex_lock(&mutex_a);
+        is_ready_thread1 = 1;
+        while (!is_ready_thread2);
+        printk(KERN_INFO "%s: Got mutex A. Now trying to acquire mutex B...\n", name);
+        mutex_lock(&mutex_b);  // This will block, causing deadlock
+        printk(KERN_INFO "%s: Got mutex B.\n", name);
+    } else {
+        printk(KERN_INFO "%s: Acquiring mutex B...\n", name);
+        mutex_lock(&mutex_b);
+        is_ready_thread2 = 1;
+        while (!is_ready_thread1);
+        printk(KERN_INFO "%s: Got mutex B. Now trying to acquire mutex A...\n", name);
+        mutex_lock(&mutex_a);  // This will block, causing deadlock
+        printk(KERN_INFO "%s: Got mutex A.\n", name);
+    }
+
+    return 0;
+}
+
+static int trigger_deadlock(void)
+{
+    thread1 = kthread_run(thread_func, (void *) "Thread1", "thread1");
+    if (IS_ERR(thread1)) {
+        printk(KERN_ERR "Failed to create thread1\n");
+        return PTR_ERR(thread1);
+    }
+
+    thread2 = kthread_run(thread_func, (void *) "Thread2", "thread2");
+    if (IS_ERR(thread2)) {
+        printk(KERN_ERR "Failed to create thread2\n");
+        kthread_stop(thread1);
+        return PTR_ERR(thread2);
+    }
+
+    return 0;
+}
+
 static int trigger_init(void) {
     if (test_type == 0)
         trigger_oom();
@@ -68,12 +120,18 @@ static int trigger_init(void) {
         trigger_oops();
     else if (test_type == 2)
         trigger_rcu();
+    else if (test_type == 3)
+        trigger_deadlock();
 
     return 0;           // 加载模块不应该有返回值，但这里返回0避免编译警告。
 }
 
 static void __exit trigger_exit(void) {
-    printk(KERN_INFO "oom_trigger: Exiting the oom_trigger LKM\n");
+    if (test_type == 3) {
+        kthread_stop(thread1);
+        kthread_stop(thread2);
+        printk(KERN_INFO "Deadlock trigger exit.\n");
+    }
 }
 
 module_init(trigger_init);