kcov: collect coverage from remote threads

xairy · Jun 11, 2018 · 7244f9e · 7244f9e
1 parent 29dcea8
commit 7244f9e
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Showing 5 changed files with 307 additions and 26 deletions.
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
@@ -5197,6 +5197,8 @@ static void hub_event(struct work_struct *work)
 	hub_dev = hub->intfdev;
 	intf = to_usb_interface(hub_dev);
 
+	kcov_remote_start(kcov_remote_handle_usb(hdev->bus->busnum));
+
 	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
 			hdev->state, hdev->maxchild,
 			/* NOTE: expects max 15 ports... */
@@ -5303,6 +5305,8 @@ static void hub_event(struct work_struct *work)
 	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
 	usb_autopm_put_interface(intf);
 	kref_put(&hub->kref, hub_release);
+
+	kcov_remote_stop();
 }
 
 static const struct usb_device_id hub_id_table[] = {

diff --git a/include/linux/kcov.h b/include/linux/kcov.h
@@ -8,6 +8,8 @@ struct task_struct;
 
 #ifdef CONFIG_KCOV
 
+#define KCOV_PER_THREAD_AREA_SIZE (PAGE_SIZE << 4)
+
 enum kcov_mode {
 	/* Coverage collection is not enabled yet. */
 	KCOV_MODE_DISABLED = 0,
@@ -25,10 +27,16 @@ enum kcov_mode {
 void kcov_task_init(struct task_struct *t);
 void kcov_task_exit(struct task_struct *t);
 
+void kcov_remote_start(u64 handle);
+void kcov_remote_stop(void);
+
 #else
 
 static inline void kcov_task_init(struct task_struct *t) {}
 static inline void kcov_task_exit(struct task_struct *t) {}
 
+static inline void kcov_remote_start(u64 handle) {}
+static inline void kcov_remote_stop(void) {}
+
 #endif /* CONFIG_KCOV */
 #endif /* _LINUX_KCOV_H */
diff --git a/include/uapi/linux/kcov.h b/include/uapi/linux/kcov.h
@@ -7,6 +7,9 @@
 #define KCOV_INIT_TRACE			_IOR('c', 1, unsigned long)
 #define KCOV_ENABLE			_IO('c', 100)
 #define KCOV_DISABLE			_IO('c', 101)
+#define KCOV_REMOTE_ENABLE		_IOW('c', 102, unsigned long)
+#define KCOV_REMOTE_TRACK		_IOW('c', 103, u64)
+#define KCOV_REMOTE_DISABLE		_IO('c', 104)
 
 enum {
 	/*
@@ -32,4 +35,11 @@ enum {
 #define KCOV_CMP_SIZE(n)        ((n) << 1)
 #define KCOV_CMP_MASK           KCOV_CMP_SIZE(3)
 
+#define KCOV_REMOTE_HANDLE_USB  0x4242424200000000ul
+
+static inline u64 kcov_remote_handle_usb(int bus)
+{
+	return KCOV_REMOTE_HANDLE_USB + (u64)bus;
+}
+
 #endif /* _LINUX_KCOV_IOCTLS_H */