lib/spinlock_debug.c: print owner on spinlock lockup
When SPIN_BUG_ON is triggered, the lock owner information is reported.
But it is omitted when spinlock lockup is detected.
This information is useful especially on the architectures which don't
implement trigger_all_cpu_backtrace() that is called just after detecting
lockup. So report it and also avoid message format duplication.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/spinlock_debug.c b/lib/spinlock_debug.c
index 4755b98..5f3eacd 100644
--- a/lib/spinlock_debug.c
+++ b/lib/spinlock_debug.c
@@ -49,13 +49,10 @@
EXPORT_SYMBOL(__rwlock_init);
-static void spin_bug(raw_spinlock_t *lock, const char *msg)
+static void spin_dump(raw_spinlock_t *lock, const char *msg)
{
struct task_struct *owner = NULL;
- if (!debug_locks_off())
- return;
-
if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
owner = lock->owner;
printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
@@ -70,6 +67,14 @@
dump_stack();
}
+static void spin_bug(raw_spinlock_t *lock, const char *msg)
+{
+ if (!debug_locks_off())
+ return;
+
+ spin_dump(lock, msg);
+}
+
#define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg)
static inline void
@@ -113,11 +118,7 @@
/* lockup suspected: */
if (print_once) {
print_once = 0;
- printk(KERN_EMERG "BUG: spinlock lockup on CPU#%d, "
- "%s/%d, %p\n",
- raw_smp_processor_id(), current->comm,
- task_pid_nr(current), lock);
- dump_stack();
+ spin_dump(lock, "lockup");
#ifdef CONFIG_SMP
trigger_all_cpu_backtrace();
#endif