kernel/cgroup.c: remove dead code
[linux-2.6.git] / kernel / lockdep.c
index a6f1ee9..3574379 100644 (file)
@@ -511,11 +511,11 @@ static void lockdep_print_held_locks(struct task_struct *curr)
        int i, depth = curr->lockdep_depth;
 
        if (!depth) {
-               printk("no locks held by %s/%d.\n", curr->comm, curr->pid);
+               printk("no locks held by %s/%d.\n", curr->comm, task_pid_nr(curr));
                return;
        }
        printk("%d lock%s held by %s/%d:\n",
-               depth, depth > 1 ? "s" : "", curr->comm, curr->pid);
+               depth, depth > 1 ? "s" : "", curr->comm, task_pid_nr(curr));
 
        for (i = 0; i < depth; i++) {
                printk(" #%d: ", i);
@@ -904,7 +904,7 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth)
        print_kernel_version();
        printk(  "-------------------------------------------------------\n");
        printk("%s/%d is trying to acquire lock:\n",
-               curr->comm, curr->pid);
+               curr->comm, task_pid_nr(curr));
        print_lock(check_source);
        printk("\nbut task is already holding lock:\n");
        print_lock(check_target);
@@ -1085,7 +1085,7 @@ print_bad_irq_dependency(struct task_struct *curr,
        print_kernel_version();
        printk(  "------------------------------------------------------\n");
        printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n",
-               curr->comm, curr->pid,
+               curr->comm, task_pid_nr(curr),
                curr->hardirq_context, hardirq_count() >> HARDIRQ_SHIFT,
                curr->softirq_context, softirq_count() >> SOFTIRQ_SHIFT,
                curr->hardirqs_enabled,
@@ -1237,7 +1237,7 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev,
        print_kernel_version();
        printk(  "---------------------------------------------\n");
        printk("%s/%d is trying to acquire lock:\n",
-               curr->comm, curr->pid);
+               curr->comm, task_pid_nr(curr));
        print_lock(next);
        printk("\nbut task is already holding lock:\n");
        print_lock(prev);
@@ -1521,7 +1521,7 @@ cache_hit:
 }
 
 static int validate_chain(struct task_struct *curr, struct lockdep_map *lock,
-               struct held_lock *hlock, int chain_head, u64 chain_key)
+               struct held_lock *hlock, int chain_head, u64 chain_key)
 {
        /*
         * Trylock needs to maintain the stack of held locks, but it
@@ -1641,7 +1641,7 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this,
                usage_str[prev_bit], usage_str[new_bit]);
 
        printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] takes:\n",
-               curr->comm, curr->pid,
+               curr->comm, task_pid_nr(curr),
                trace_hardirq_context(curr), hardirq_count() >> HARDIRQ_SHIFT,
                trace_softirq_context(curr), softirq_count() >> SOFTIRQ_SHIFT,
                trace_hardirqs_enabled(curr),
@@ -1694,7 +1694,7 @@ print_irq_inversion_bug(struct task_struct *curr, struct lock_class *other,
        print_kernel_version();
        printk(  "---------------------------------------------------------\n");
        printk("%s/%d just changed the state of lock:\n",
-               curr->comm, curr->pid);
+               curr->comm, task_pid_nr(curr));
        print_lock(this);
        if (forwards)
                printk("but this lock took another, %s-irq-unsafe lock in the past:\n", irqclass);
@@ -2424,7 +2424,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
                return 0;
 
        /*
-        * Calculate the chain hash: it's the combined has of all the
+        * Calculate the chain hash: it's the combined hash of all the
         * lock keys along the dependency chain. We save the hash value
         * at every step so that we can get the current hash easily
         * after unlock. The chain hash is then used to cache dependency
@@ -2487,7 +2487,7 @@ print_unlock_inbalance_bug(struct task_struct *curr, struct lockdep_map *lock,
        printk(  "[ BUG: bad unlock balance detected! ]\n");
        printk(  "-------------------------------------\n");
        printk("%s/%d is trying to release lock (",
-               curr->comm, curr->pid);
+               curr->comm, task_pid_nr(curr));
        print_lockdep_cache(lock);
        printk(") at:\n");
        print_ip_sym(ip);
@@ -2654,10 +2654,15 @@ static void check_flags(unsigned long flags)
        if (!debug_locks)
                return;
 
-       if (irqs_disabled_flags(flags))
-               DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled);
-       else
-               DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled);
+       if (irqs_disabled_flags(flags)) {
+               if (DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)) {
+                       printk("possible reason: unannotated irqs-off.\n");
+               }
+       } else {
+               if (DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled)) {
+                       printk("possible reason: unannotated irqs-on.\n");
+               }
+       }
 
        /*
         * We dont accurately track softirq state in e.g.
@@ -2737,7 +2742,7 @@ print_lock_contention_bug(struct task_struct *curr, struct lockdep_map *lock,
        printk(  "[ BUG: bad contention detected! ]\n");
        printk(  "---------------------------------\n");
        printk("%s/%d is trying to contend lock (",
-               curr->comm, curr->pid);
+               curr->comm, task_pid_nr(curr));
        print_lockdep_cache(lock);
        printk(") at:\n");
        print_ip_sym(ip);
@@ -2927,7 +2932,7 @@ static void zap_class(struct lock_class *class)
 
 }
 
-static inline int within(void *addr, void *start, unsigned long size)
+static inline int within(const void *addr, void *start, unsigned long size)
 {
        return addr >= start && addr < start + size;
 }
@@ -2938,9 +2943,10 @@ void lockdep_free_key_range(void *start, unsigned long size)
        struct list_head *head;
        unsigned long flags;
        int i;
+       int locked;
 
        raw_local_irq_save(flags);
-       graph_lock();
+       locked = graph_lock();
 
        /*
         * Unhash all classes that were created by this module:
@@ -2949,12 +2955,16 @@ void lockdep_free_key_range(void *start, unsigned long size)
                head = classhash_table + i;
                if (list_empty(head))
                        continue;
-               list_for_each_entry_safe(class, next, head, hash_entry)
+               list_for_each_entry_safe(class, next, head, hash_entry) {
                        if (within(class->key, start, size))
                                zap_class(class);
+                       else if (within(class->name, start, size))
+                               zap_class(class);
+               }
        }
 
-       graph_unlock();
+       if (locked)
+               graph_unlock();
        raw_local_irq_restore(flags);
 }
 
@@ -2964,6 +2974,7 @@ void lockdep_reset_lock(struct lockdep_map *lock)
        struct list_head *head;
        unsigned long flags;
        int i, j;
+       int locked;
 
        raw_local_irq_save(flags);
 
@@ -2982,7 +2993,7 @@ void lockdep_reset_lock(struct lockdep_map *lock)
         * Debug check: in the end all mapped classes should
         * be gone.
         */
-       graph_lock();
+       locked = graph_lock();
        for (i = 0; i < CLASSHASH_SIZE; i++) {
                head = classhash_table + i;
                if (list_empty(head))
@@ -2995,7 +3006,8 @@ void lockdep_reset_lock(struct lockdep_map *lock)
                        }
                }
        }
-       graph_unlock();
+       if (locked)
+               graph_unlock();
 
 out_restore:
        raw_local_irq_restore(flags);
@@ -3054,11 +3066,6 @@ void __init lockdep_info(void)
 #endif
 }
 
-static inline int in_range(const void *start, const void *addr, const void *end)
-{
-       return addr >= start && addr <= end;
-}
-
 static void
 print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
                     const void *mem_to, struct held_lock *hlock)
@@ -3072,7 +3079,7 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
        printk(  "[ BUG: held lock freed! ]\n");
        printk(  "-------------------------\n");
        printk("%s/%d is freeing memory %p-%p, with a lock still held there!\n",
-               curr->comm, curr->pid, mem_from, mem_to-1);
+               curr->comm, task_pid_nr(curr), mem_from, mem_to-1);
        print_lock(hlock);
        lockdep_print_held_locks(curr);
 
@@ -3080,6 +3087,13 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
        dump_stack();
 }
 
+static inline int not_in_range(const void* mem_from, unsigned long mem_len,
+                               const void* lock_from, unsigned long lock_len)
+{
+       return lock_from + lock_len <= mem_from ||
+               mem_from + mem_len <= lock_from;
+}
+
 /*
  * Called when kernel memory is freed (or unmapped), or if a lock
  * is destroyed or reinitialized - this code checks whether there is
@@ -3087,7 +3101,6 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
  */
 void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
 {
-       const void *mem_to = mem_from + mem_len, *lock_from, *lock_to;
        struct task_struct *curr = current;
        struct held_lock *hlock;
        unsigned long flags;
@@ -3100,14 +3113,11 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
        for (i = 0; i < curr->lockdep_depth; i++) {
                hlock = curr->held_locks + i;
 
-               lock_from = (void *)hlock->instance;
-               lock_to = (void *)(hlock->instance + 1);
-
-               if (!in_range(mem_from, lock_from, mem_to) &&
-                                       !in_range(mem_from, lock_to, mem_to))
+               if (not_in_range(mem_from, mem_len, hlock->instance,
+                                       sizeof(*hlock->instance)))
                        continue;
 
-               print_freed_lock_bug(curr, mem_from, mem_to, hlock);
+               print_freed_lock_bug(curr, mem_from, mem_from + mem_len, hlock);
                break;
        }
        local_irq_restore(flags);
@@ -3125,7 +3135,7 @@ static void print_held_locks_bug(struct task_struct *curr)
        printk(  "[ BUG: lock held at task exit time! ]\n");
        printk(  "-------------------------------------\n");
        printk("%s/%d is exiting with locks still held!\n",
-               curr->comm, curr->pid);
+               curr->comm, task_pid_nr(curr));
        lockdep_print_held_locks(curr);
 
        printk("\nstack backtrace:\n");
@@ -3173,6 +3183,13 @@ retry:
                printk(" locked it.\n");
 
        do_each_thread(g, p) {
+               /*
+                * It's not reliable to print a task's held locks
+                * if it's not sleeping (or if it's not the current
+                * task):
+                */
+               if (p->state == TASK_RUNNING && p != current)
+                       continue;
                if (p->lockdep_depth)
                        lockdep_print_held_locks(p);
                if (!unlock)
@@ -3189,7 +3206,11 @@ retry:
 
 EXPORT_SYMBOL_GPL(debug_show_all_locks);
 
-void debug_show_held_locks(struct task_struct *task)
+/*
+ * Careful: only use this function if you are sure that
+ * the task cannot run in parallel!
+ */
+void __debug_show_held_locks(struct task_struct *task)
 {
        if (unlikely(!debug_locks)) {
                printk("INFO: lockdep is turned off.\n");
@@ -3197,6 +3218,12 @@ void debug_show_held_locks(struct task_struct *task)
        }
        lockdep_print_held_locks(task);
 }
+EXPORT_SYMBOL_GPL(__debug_show_held_locks);
+
+void debug_show_held_locks(struct task_struct *task)
+{
+               __debug_show_held_locks(task);
+}
 
 EXPORT_SYMBOL_GPL(debug_show_held_locks);