dma-debug: allow DMA_BIDIRECTIONAL mappings to be synced with DMA_FROM_DEVICE and
[safe/jmp/linux-2.6] / lib / spinlock_debug.c
index dcd4be9..4755b98 100644 (file)
@@ -6,40 +6,74 @@
  * DEBUG_SPINLOCK.
  */
 
-#include <linux/config.h>
 #include <linux/spinlock.h>
+#include <linux/nmi.h>
 #include <linux/interrupt.h>
+#include <linux/debug_locks.h>
 #include <linux/delay.h>
+#include <linux/module.h>
 
-static void spin_bug(spinlock_t *lock, const char *msg)
+void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
+                         struct lock_class_key *key)
 {
-       static long print_once = 1;
-       struct task_struct *owner = NULL;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       /*
+        * Make sure we are not reinitializing a held lock:
+        */
+       debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+       lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+       lock->raw_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+       lock->magic = SPINLOCK_MAGIC;
+       lock->owner = SPINLOCK_OWNER_INIT;
+       lock->owner_cpu = -1;
+}
 
-       if (xchg(&print_once, 0)) {
-               if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
-                       owner = lock->owner;
-               printk("BUG: spinlock %s on CPU#%d, %s/%d\n",
-                       msg, raw_smp_processor_id(),
-                       current->comm, current->pid);
-               printk(" lock: %p, .magic: %08x, .owner: %s/%d, .owner_cpu: %d\n",
-                       lock, lock->magic,
-                       owner ? owner->comm : "<none>",
-                       owner ? owner->pid : -1,
-                       lock->owner_cpu);
-               dump_stack();
-#ifdef CONFIG_SMP
-               /*
-                * We cannot continue on SMP:
-                */
-//             panic("bad locking");
+EXPORT_SYMBOL(__raw_spin_lock_init);
+
+void __rwlock_init(rwlock_t *lock, const char *name,
+                  struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       /*
+        * Make sure we are not reinitializing a held lock:
+        */
+       debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+       lockdep_init_map(&lock->dep_map, name, key, 0);
 #endif
-       }
+       lock->raw_lock = (arch_rwlock_t) __ARCH_RW_LOCK_UNLOCKED;
+       lock->magic = RWLOCK_MAGIC;
+       lock->owner = SPINLOCK_OWNER_INIT;
+       lock->owner_cpu = -1;
+}
+
+EXPORT_SYMBOL(__rwlock_init);
+
+static void spin_bug(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",
+               msg, raw_smp_processor_id(),
+               current->comm, task_pid_nr(current));
+       printk(KERN_EMERG " lock: %p, .magic: %08x, .owner: %s/%d, "
+                       ".owner_cpu: %d\n",
+               lock, lock->magic,
+               owner ? owner->comm : "<none>",
+               owner ? task_pid_nr(owner) : -1,
+               lock->owner_cpu);
+       dump_stack();
 }
 
 #define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg)
 
-static inline void debug_spin_lock_before(spinlock_t *lock)
+static inline void
+debug_spin_lock_before(raw_spinlock_t *lock)
 {
        SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
        SPIN_BUG_ON(lock->owner == current, lock, "recursion");
@@ -47,16 +81,16 @@ static inline void debug_spin_lock_before(spinlock_t *lock)
                                                        lock, "cpu recursion");
 }
 
-static inline void debug_spin_lock_after(spinlock_t *lock)
+static inline void debug_spin_lock_after(raw_spinlock_t *lock)
 {
        lock->owner_cpu = raw_smp_processor_id();
        lock->owner = current;
 }
 
-static inline void debug_spin_unlock(spinlock_t *lock)
+static inline void debug_spin_unlock(raw_spinlock_t *lock)
 {
        SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
-       SPIN_BUG_ON(!spin_is_locked(lock), lock, "already unlocked");
+       SPIN_BUG_ON(!raw_spin_is_locked(lock), lock, "already unlocked");
        SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
        SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
                                                        lock, "wrong CPU");
@@ -64,39 +98,44 @@ static inline void debug_spin_unlock(spinlock_t *lock)
        lock->owner_cpu = -1;
 }
 
-static void __spin_lock_debug(spinlock_t *lock)
+static void __spin_lock_debug(raw_spinlock_t *lock)
 {
-       int print_once = 1;
        u64 i;
+       u64 loops = loops_per_jiffy * HZ;
+       int print_once = 1;
 
        for (;;) {
-               for (i = 0; i < loops_per_jiffy * HZ; i++) {
-                       cpu_relax();
-                       if (__raw_spin_trylock(&lock->raw_lock))
+               for (i = 0; i < loops; i++) {
+                       if (arch_spin_trylock(&lock->raw_lock))
                                return;
+                       __delay(1);
                }
                /* lockup suspected: */
                if (print_once) {
                        print_once = 0;
-                       printk("BUG: spinlock lockup on CPU#%d, %s/%d, %p\n",
+                       printk(KERN_EMERG "BUG: spinlock lockup on CPU#%d, "
+                                       "%s/%d, %p\n",
                                raw_smp_processor_id(), current->comm,
-                               current->pid, lock);
+                               task_pid_nr(current), lock);
                        dump_stack();
+#ifdef CONFIG_SMP
+                       trigger_all_cpu_backtrace();
+#endif
                }
        }
 }
 
-void _raw_spin_lock(spinlock_t *lock)
+void do_raw_spin_lock(raw_spinlock_t *lock)
 {
        debug_spin_lock_before(lock);
-       if (unlikely(!__raw_spin_trylock(&lock->raw_lock)))
+       if (unlikely(!arch_spin_trylock(&lock->raw_lock)))
                __spin_lock_debug(lock);
        debug_spin_lock_after(lock);
 }
 
-int _raw_spin_trylock(spinlock_t *lock)
+int do_raw_spin_trylock(raw_spinlock_t *lock)
 {
-       int ret = __raw_spin_trylock(&lock->raw_lock);
+       int ret = arch_spin_trylock(&lock->raw_lock);
 
        if (ret)
                debug_spin_lock_after(lock);
@@ -109,64 +148,60 @@ int _raw_spin_trylock(spinlock_t *lock)
        return ret;
 }
 
-void _raw_spin_unlock(spinlock_t *lock)
+void do_raw_spin_unlock(raw_spinlock_t *lock)
 {
        debug_spin_unlock(lock);
-       __raw_spin_unlock(&lock->raw_lock);
+       arch_spin_unlock(&lock->raw_lock);
 }
 
 static void rwlock_bug(rwlock_t *lock, const char *msg)
 {
-       static long print_once = 1;
+       if (!debug_locks_off())
+               return;
 
-       if (xchg(&print_once, 0)) {
-               printk("BUG: rwlock %s on CPU#%d, %s/%d, %p\n", msg,
-                       raw_smp_processor_id(), current->comm,
-                       current->pid, lock);
-               dump_stack();
-#ifdef CONFIG_SMP
-               /*
-                * We cannot continue on SMP:
-                */
-               panic("bad locking");
-#endif
-       }
+       printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n",
+               msg, raw_smp_processor_id(), current->comm,
+               task_pid_nr(current), lock);
+       dump_stack();
 }
 
 #define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg)
 
+#if 0          /* __write_lock_debug() can lock up - maybe this can too? */
 static void __read_lock_debug(rwlock_t *lock)
 {
-       int print_once = 1;
        u64 i;
+       u64 loops = loops_per_jiffy * HZ;
+       int print_once = 1;
 
        for (;;) {
-               for (i = 0; i < loops_per_jiffy * HZ; i++) {
-                       cpu_relax();
-                       if (__raw_read_trylock(&lock->raw_lock))
+               for (i = 0; i < loops; i++) {
+                       if (arch_read_trylock(&lock->raw_lock))
                                return;
+                       __delay(1);
                }
                /* lockup suspected: */
                if (print_once) {
                        print_once = 0;
-                       printk("BUG: read-lock lockup on CPU#%d, %s/%d, %p\n",
+                       printk(KERN_EMERG "BUG: read-lock lockup on CPU#%d, "
+                                       "%s/%d, %p\n",
                                raw_smp_processor_id(), current->comm,
                                current->pid, lock);
                        dump_stack();
                }
        }
 }
+#endif
 
-void _raw_read_lock(rwlock_t *lock)
+void do_raw_read_lock(rwlock_t *lock)
 {
        RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
-       if (unlikely(!__raw_read_trylock(&lock->raw_lock)))
-               __read_lock_debug(lock);
+       arch_read_lock(&lock->raw_lock);
 }
 
-int _raw_read_trylock(rwlock_t *lock)
+int do_raw_read_trylock(rwlock_t *lock)
 {
-       int ret = __raw_read_trylock(&lock->raw_lock);
+       int ret = arch_read_trylock(&lock->raw_lock);
 
 #ifndef CONFIG_SMP
        /*
@@ -177,10 +212,10 @@ int _raw_read_trylock(rwlock_t *lock)
        return ret;
 }
 
-void _raw_read_unlock(rwlock_t *lock)
+void do_raw_read_unlock(rwlock_t *lock)
 {
        RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
-       __raw_read_unlock(&lock->raw_lock);
+       arch_read_unlock(&lock->raw_lock);
 }
 
 static inline void debug_write_lock_before(rwlock_t *lock)
@@ -207,39 +242,42 @@ static inline void debug_write_unlock(rwlock_t *lock)
        lock->owner_cpu = -1;
 }
 
+#if 0          /* This can cause lockups */
 static void __write_lock_debug(rwlock_t *lock)
 {
-       int print_once = 1;
        u64 i;
+       u64 loops = loops_per_jiffy * HZ;
+       int print_once = 1;
 
        for (;;) {
-               for (i = 0; i < loops_per_jiffy * HZ; i++) {
-                       cpu_relax();
-                       if (__raw_write_trylock(&lock->raw_lock))
+               for (i = 0; i < loops; i++) {
+                       if (arch_write_trylock(&lock->raw_lock))
                                return;
+                       __delay(1);
                }
                /* lockup suspected: */
                if (print_once) {
                        print_once = 0;
-                       printk("BUG: write-lock lockup on CPU#%d, %s/%d, %p\n",
+                       printk(KERN_EMERG "BUG: write-lock lockup on CPU#%d, "
+                                       "%s/%d, %p\n",
                                raw_smp_processor_id(), current->comm,
                                current->pid, lock);
                        dump_stack();
                }
        }
 }
+#endif
 
-void _raw_write_lock(rwlock_t *lock)
+void do_raw_write_lock(rwlock_t *lock)
 {
        debug_write_lock_before(lock);
-       if (unlikely(!__raw_write_trylock(&lock->raw_lock)))
-               __write_lock_debug(lock);
+       arch_write_lock(&lock->raw_lock);
        debug_write_lock_after(lock);
 }
 
-int _raw_write_trylock(rwlock_t *lock)
+int do_raw_write_trylock(rwlock_t *lock)
 {
-       int ret = __raw_write_trylock(&lock->raw_lock);
+       int ret = arch_write_trylock(&lock->raw_lock);
 
        if (ret)
                debug_write_lock_after(lock);
@@ -252,8 +290,8 @@ int _raw_write_trylock(rwlock_t *lock)
        return ret;
 }
 
-void _raw_write_unlock(rwlock_t *lock)
+void do_raw_write_unlock(rwlock_t *lock)
 {
        debug_write_unlock(lock);
-       __raw_write_unlock(&lock->raw_lock);
+       arch_write_unlock(&lock->raw_lock);
 }