feat(lab02): add ex07 resouces

src/01-skeleton/s02e07-sleeping.c

@@ -0,0 +1,94 @@
+#include <linux/module.h>	// needed by all modules
+#include <linux/init.h>		// needed for macros
+#include <linux/kernel.h>	// needed for debugging
+
+
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/wait.h>
+#include <linux/atomic.h>
+
+
+#define TIMEOUT_S 5
+
+DECLARE_WAIT_QUEUE_HEAD(queue_1);
+DECLARE_WAIT_QUEUE_HEAD(queue_2);
+
+static struct task_struct* thread_1;
+static struct task_struct* thread_2;
+static atomic_t trigger = ATOMIC_INIT(0);
+
+
+int thread_skeleton_1(void* data) {
+    // must wait 5 seconds and start thread 2
+
+    pr_info("Thread 1 started\n");
+
+    while (!kthread_should_stop()) {
+        pr_info("Thread 1 wakes up\n");
+        ssleep(TIMEOUT_S);
+
+        // Setup trigger for condition of the thread 2
+        atomic_set(&trigger, 1);
+
+        // Wake up thread 2
+        wake_up_interruptible(&queue_2);
+
+        // Wait until thread 2 has reset the trigger
+        wait_event_interruptible(queue_1, atomic_read(&trigger) == 0 || kthread_should_stop());
+
+    }
+
+    return 0;
+}
+
+int thread_skeleton_2(void* data) {
+    // have to PING when wakes up
+
+    pr_info("Thread 2 started\n");
+
+
+    while (!kthread_should_stop()) {
+
+        // wait until trigger is set up
+        wait_event_interruptible(queue_2, atomic_read(&trigger) == 1 || kthread_should_stop());
+        pr_info("Thread 2 wakes up\n");
+
+        // reset trigger
+        atomic_set(&trigger, 0);
+
+        // wake up thread 1
+        wake_up_interruptible(&queue_1);
+    }
+
+    return 0;
+}
+
+
+void sleeping_init(void) {
+    pr_info("Initialize kernel thread\n");
+
+    atomic_set(&trigger, 0);
+
+    thread_1 = kthread_run(thread_skeleton_1, NULL, "Thread 1 - sleeping");
+    if (IS_ERR(thread_1)) {
+        pr_err("Failed to create kernel thread 1\n");
+        return;
+    }
+
+    thread_2 = kthread_run(thread_skeleton_2, NULL, "Thread 2 - sleeping");
+    if (IS_ERR(thread_2)) {
+        pr_err("Failed to create kernel thread 1\n");
+        return;
+    }
+
+    pr_info("Kernel thread sleeping initialized\n");
+
+}
+
+void sleeping_exit(void) {
+    pr_info("Exiting kernel sleeping thread\n");
+    kthread_stop(thread_1);
+    kthread_stop(thread_2);
+    pr_info("Kernel thread sleeping exited\n");
+}