idr: deprecate idr_remove_all()

[~andy/linux] / lib / spinlock_debug.c

diff --git a/lib/spinlock_debug.c b/lib/spinlock_debug.c
index e91fbc23fff121915217a8e5c53c29a2b52aeba4..0374a596cffac8439d36875ba2bd248753caf886 100644 (file)
--- a/lib/spinlock_debug.c
+++ b/lib/spinlock_debug.c
@@ -58,7 +58,7 @@ static void spin_dump(raw_spinlock_t *lock, const char *msg)
        printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
                msg, raw_smp_processor_id(),
                current->comm, task_pid_nr(current));
-       printk(KERN_EMERG " lock: %ps, .magic: %08x, .owner: %s/%d, "
+       printk(KERN_EMERG " lock: %pS, .magic: %08x, .owner: %s/%d, "
                        ".owner_cpu: %d\n",
                lock, lock->magic,
                owner ? owner->comm : "<none>",
@@ -107,23 +107,27 @@ static void __spin_lock_debug(raw_spinlock_t *lock)
 {
        u64 i;
        u64 loops = loops_per_jiffy * HZ;
-       int print_once = 1;
 
-       for (;;) {
-               for (i = 0; i < loops; i++) {
-                       if (arch_spin_trylock(&lock->raw_lock))
-                               return;
-                       __delay(1);
-               }
-               /* lockup suspected: */
-               if (print_once) {
-                       print_once = 0;
-                       spin_dump(lock, "lockup suspected");
+       for (i = 0; i < loops; i++) {
+               if (arch_spin_trylock(&lock->raw_lock))
+                       return;
+               __delay(1);
+       }
+       /* lockup suspected: */
+       spin_dump(lock, "lockup suspected");
 #ifdef CONFIG_SMP
-                       trigger_all_cpu_backtrace();
+       trigger_all_cpu_backtrace();
 #endif
-               }
-       }
+
+       /*
+        * The trylock above was causing a livelock.  Give the lower level arch
+        * specific lock code a chance to acquire the lock. We have already
+        * printed a warning/backtrace at this point. The non-debug arch
+        * specific code might actually succeed in acquiring the lock.  If it is
+        * not successful, the end-result is the same - there is no forward
+        * progress.
+        */
+       arch_spin_lock(&lock->raw_lock);
 }
 
 void do_raw_spin_lock(raw_spinlock_t *lock)