kcov, usbip: collect coverage from vhci_rx_loop

Add kcov_remote_start()/kcov_remote_stop() annotations to the
vhci_rx_loop() function, which is responsible for parsing USB/IP packets
coming into USB/IP client.

Since vhci_rx_loop() threads are spawned per vhci_hcd device instance, the
common kcov handle is used for kcov_remote_start()/stop() annotations
(see Documentation/dev-tools/kcov.rst for details). As the result kcov
can now be used to collect coverage from vhci_rx_loop() threads.

Co-developed-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Nazime Hande Harputluoglu <handeharputlu@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Link: https://lore.kernel.org/r/f8114050f8d65aa0bc801318b1db532d9f432447.1606175386.git.andreyknvl@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/usbip/usbip_common.h b/drivers/usb/usbip/usbip_common.h
index 8be857a..d60ce17 100644 (file)
--- a/drivers/usb/usbip/usbip_common.h
+++ b/drivers/usb/usbip/usbip_common.h
@@ -277,6 +277,10 @@ struct usbip_device {
                void (*reset)(struct usbip_device *);
                void (*unusable)(struct usbip_device *);
        } eh_ops;
+
+#ifdef CONFIG_KCOV
+       u64 kcov_handle;
+#endif
 };
 
 #define kthread_get_run(threadfn, data, namefmt, ...)                     \
@@ -337,4 +341,29 @@ static inline int interface_to_devnum(struct usb_interface *interface)
        return udev->devnum;
 }
 
+#ifdef CONFIG_KCOV
+
+static inline void usbip_kcov_handle_init(struct usbip_device *ud)
+{
+       ud->kcov_handle = kcov_common_handle();
+}
+
+static inline void usbip_kcov_remote_start(struct usbip_device *ud)
+{
+       kcov_remote_start_common(ud->kcov_handle);
+}
+
+static inline void usbip_kcov_remote_stop(void)
+{
+       kcov_remote_stop();
+}
+
+#else /* CONFIG_KCOV */
+
+static inline void usbip_kcov_handle_init(struct usbip_device *ud) { }
+static inline void usbip_kcov_remote_start(struct usbip_device *ud) { }
+static inline void usbip_kcov_remote_stop(void) { }
+
+#endif /* CONFIG_KCOV */
+
 #endif /* __USBIP_COMMON_H */

diff --git a/drivers/usb/usbip/vhci_rx.c b/drivers/usb/usbip/vhci_rx.c
index 266024c..7f2d1c2 100644 (file)
--- a/drivers/usb/usbip/vhci_rx.c
+++ b/drivers/usb/usbip/vhci_rx.c
@@ -261,7 +261,9 @@ int vhci_rx_loop(void *data)
                if (usbip_event_happened(ud))
                        break;
 
+               usbip_kcov_remote_start(ud);
                vhci_rx_pdu(ud);
+               usbip_kcov_remote_stop();
        }
 
        return 0;

diff --git a/drivers/usb/usbip/vhci_sysfs.c b/drivers/usb/usbip/vhci_sysfs.c
index be37aec..96e5371 100644 (file)
--- a/drivers/usb/usbip/vhci_sysfs.c
+++ b/drivers/usb/usbip/vhci_sysfs.c
@@ -383,6 +383,7 @@ static ssize_t attach_store(struct device *dev, struct device_attribute *attr,
        vdev->ud.sockfd     = sockfd;
        vdev->ud.tcp_socket = socket;
        vdev->ud.status     = VDEV_ST_NOTASSIGNED;
+       usbip_kcov_handle_init(&vdev->ud);
 
        spin_unlock(&vdev->ud.lock);
        spin_unlock_irqrestore(&vhci->lock, flags);