Done opencode in_serving_softirq() checks in __usb_hcd_giveback_urb() to
avoid cluttering the code, hide them in kcov helpers instead.
Fixes: aee9ddb1d371 ("kcov, usb: only collect coverage from __usb_hcd_giveback_urb in softirq")
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
Changes v1->v2:
- Fix a typo in the commit description and in a comment in the patch.
---
drivers/usb/core/hcd.c | 8 +++-----
include/linux/kcov.h | 21 +++++++++++++++++++++
2 files changed, 24 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 60886a7464c3..ad5a0f405a75 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1649,14 +1649,12 @@ static void __usb_hcd_giveback_urb(struct urb *urb)
urb->status = status;
/*
* This function can be called in task context inside another remote
- * coverage collection section, but KCOV doesn't support that kind of
+ * coverage collection section, but kcov doesn't support that kind of
* recursion yet. Only collect coverage in softirq context for now.
*/
- if (in_serving_softirq())
- kcov_remote_start_usb((u64)urb->dev->bus->busnum);
+ kcov_remote_start_usb_softirq((u64)urb->dev->bus->busnum);
urb->complete(urb);
- if (in_serving_softirq())
- kcov_remote_stop();
+ kcov_remote_stop_softirq();
usb_anchor_resume_wakeups(anchor);
atomic_dec(&urb->use_count);
diff --git a/include/linux/kcov.h b/include/linux/kcov.h
index a10e84707d82..18306ef8ad5a 100644
--- a/include/linux/kcov.h
+++ b/include/linux/kcov.h
@@ -52,6 +52,25 @@ static inline void kcov_remote_start_usb(u64 id)
kcov_remote_start(kcov_remote_handle(KCOV_SUBSYSTEM_USB, id));
}
+/*
+ * The softirq flavor of kcov_remote_*() functions is introduced as a temporary
+ * workaround for kcov's lack of nested remote coverage sections support in
+ * task context. Adding suport for nested sections is tracked in:
+ * https://bugzilla.kernel.org/show_bug.cgi?id=210337
+ */
+
+static inline void kcov_remote_start_usb_softirq(u64 id)
+{
+ if (in_serving_softirq())
+ kcov_remote_start_usb(id);
+}
+
+static inline void kcov_remote_stop_softirq(void)
+{
+ if (in_serving_softirq())
+ kcov_remote_stop();
+}
+
#else
static inline void kcov_task_init(struct task_struct *t) {}
@@ -66,6 +85,8 @@ static inline u64 kcov_common_handle(void)
}
static inline void kcov_remote_start_common(u64 id) {}
static inline void kcov_remote_start_usb(u64 id) {}
+static inline void kcov_remote_start_usb_softirq(u64 id) {}
+static inline void kcov_remote_stop_softirq(void) {}
#endif /* CONFIG_KCOV */
#endif /* _LINUX_KCOV_H */
--
2.29.2.729.g45daf8777d-goog
