smsc95xx: mark link down on startup and let PHY interrupt deal with carrier changes
[zen-stable.git] / lib / spinlock_debug.c
blob5f3eacdd6178d122b9d35fc8e8f9daf12e3b119b
1 /*
2 * Copyright 2005, Red Hat, Inc., Ingo Molnar
3 * Released under the General Public License (GPL).
5 * This file contains the spinlock/rwlock implementations for
6 * DEBUG_SPINLOCK.
7 */
9 #include <linux/spinlock.h>
10 #include <linux/nmi.h>
11 #include <linux/interrupt.h>
12 #include <linux/debug_locks.h>
13 #include <linux/delay.h>
14 #include <linux/module.h>
16 void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
17 struct lock_class_key *key)
19 #ifdef CONFIG_DEBUG_LOCK_ALLOC
21 * Make sure we are not reinitializing a held lock:
23 debug_check_no_locks_freed((void *)lock, sizeof(*lock));
24 lockdep_init_map(&lock->dep_map, name, key, 0);
25 #endif
26 lock->raw_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
27 lock->magic = SPINLOCK_MAGIC;
28 lock->owner = SPINLOCK_OWNER_INIT;
29 lock->owner_cpu = -1;
32 EXPORT_SYMBOL(__raw_spin_lock_init);
34 void __rwlock_init(rwlock_t *lock, const char *name,
35 struct lock_class_key *key)
37 #ifdef CONFIG_DEBUG_LOCK_ALLOC
39 * Make sure we are not reinitializing a held lock:
41 debug_check_no_locks_freed((void *)lock, sizeof(*lock));
42 lockdep_init_map(&lock->dep_map, name, key, 0);
43 #endif
44 lock->raw_lock = (arch_rwlock_t) __ARCH_RW_LOCK_UNLOCKED;
45 lock->magic = RWLOCK_MAGIC;
46 lock->owner = SPINLOCK_OWNER_INIT;
47 lock->owner_cpu = -1;
50 EXPORT_SYMBOL(__rwlock_init);
52 static void spin_dump(raw_spinlock_t *lock, const char *msg)
54 struct task_struct *owner = NULL;
56 if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
57 owner = lock->owner;
58 printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
59 msg, raw_smp_processor_id(),
60 current->comm, task_pid_nr(current));
61 printk(KERN_EMERG " lock: %p, .magic: %08x, .owner: %s/%d, "
62 ".owner_cpu: %d\n",
63 lock, lock->magic,
64 owner ? owner->comm : "<none>",
65 owner ? task_pid_nr(owner) : -1,
66 lock->owner_cpu);
67 dump_stack();
70 static void spin_bug(raw_spinlock_t *lock, const char *msg)
72 if (!debug_locks_off())
73 return;
75 spin_dump(lock, msg);
78 #define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg)
80 static inline void
81 debug_spin_lock_before(raw_spinlock_t *lock)
83 SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
84 SPIN_BUG_ON(lock->owner == current, lock, "recursion");
85 SPIN_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
86 lock, "cpu recursion");
89 static inline void debug_spin_lock_after(raw_spinlock_t *lock)
91 lock->owner_cpu = raw_smp_processor_id();
92 lock->owner = current;
95 static inline void debug_spin_unlock(raw_spinlock_t *lock)
97 SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
98 SPIN_BUG_ON(!raw_spin_is_locked(lock), lock, "already unlocked");
99 SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
100 SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
101 lock, "wrong CPU");
102 lock->owner = SPINLOCK_OWNER_INIT;
103 lock->owner_cpu = -1;
106 static void __spin_lock_debug(raw_spinlock_t *lock)
108 u64 i;
109 u64 loops = loops_per_jiffy * HZ;
110 int print_once = 1;
112 for (;;) {
113 for (i = 0; i < loops; i++) {
114 if (arch_spin_trylock(&lock->raw_lock))
115 return;
116 __delay(1);
118 /* lockup suspected: */
119 if (print_once) {
120 print_once = 0;
121 spin_dump(lock, "lockup");
122 #ifdef CONFIG_SMP
123 trigger_all_cpu_backtrace();
124 #endif
129 void do_raw_spin_lock(raw_spinlock_t *lock)
131 debug_spin_lock_before(lock);
132 if (unlikely(!arch_spin_trylock(&lock->raw_lock)))
133 __spin_lock_debug(lock);
134 debug_spin_lock_after(lock);
137 int do_raw_spin_trylock(raw_spinlock_t *lock)
139 int ret = arch_spin_trylock(&lock->raw_lock);
141 if (ret)
142 debug_spin_lock_after(lock);
143 #ifndef CONFIG_SMP
145 * Must not happen on UP:
147 SPIN_BUG_ON(!ret, lock, "trylock failure on UP");
148 #endif
149 return ret;
152 void do_raw_spin_unlock(raw_spinlock_t *lock)
154 debug_spin_unlock(lock);
155 arch_spin_unlock(&lock->raw_lock);
158 static void rwlock_bug(rwlock_t *lock, const char *msg)
160 if (!debug_locks_off())
161 return;
163 printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n",
164 msg, raw_smp_processor_id(), current->comm,
165 task_pid_nr(current), lock);
166 dump_stack();
169 #define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg)
171 #if 0 /* __write_lock_debug() can lock up - maybe this can too? */
172 static void __read_lock_debug(rwlock_t *lock)
174 u64 i;
175 u64 loops = loops_per_jiffy * HZ;
176 int print_once = 1;
178 for (;;) {
179 for (i = 0; i < loops; i++) {
180 if (arch_read_trylock(&lock->raw_lock))
181 return;
182 __delay(1);
184 /* lockup suspected: */
185 if (print_once) {
186 print_once = 0;
187 printk(KERN_EMERG "BUG: read-lock lockup on CPU#%d, "
188 "%s/%d, %p\n",
189 raw_smp_processor_id(), current->comm,
190 current->pid, lock);
191 dump_stack();
195 #endif
197 void do_raw_read_lock(rwlock_t *lock)
199 RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
200 arch_read_lock(&lock->raw_lock);
203 int do_raw_read_trylock(rwlock_t *lock)
205 int ret = arch_read_trylock(&lock->raw_lock);
207 #ifndef CONFIG_SMP
209 * Must not happen on UP:
211 RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
212 #endif
213 return ret;
216 void do_raw_read_unlock(rwlock_t *lock)
218 RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
219 arch_read_unlock(&lock->raw_lock);
222 static inline void debug_write_lock_before(rwlock_t *lock)
224 RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
225 RWLOCK_BUG_ON(lock->owner == current, lock, "recursion");
226 RWLOCK_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
227 lock, "cpu recursion");
230 static inline void debug_write_lock_after(rwlock_t *lock)
232 lock->owner_cpu = raw_smp_processor_id();
233 lock->owner = current;
236 static inline void debug_write_unlock(rwlock_t *lock)
238 RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
239 RWLOCK_BUG_ON(lock->owner != current, lock, "wrong owner");
240 RWLOCK_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
241 lock, "wrong CPU");
242 lock->owner = SPINLOCK_OWNER_INIT;
243 lock->owner_cpu = -1;
246 #if 0 /* This can cause lockups */
247 static void __write_lock_debug(rwlock_t *lock)
249 u64 i;
250 u64 loops = loops_per_jiffy * HZ;
251 int print_once = 1;
253 for (;;) {
254 for (i = 0; i < loops; i++) {
255 if (arch_write_trylock(&lock->raw_lock))
256 return;
257 __delay(1);
259 /* lockup suspected: */
260 if (print_once) {
261 print_once = 0;
262 printk(KERN_EMERG "BUG: write-lock lockup on CPU#%d, "
263 "%s/%d, %p\n",
264 raw_smp_processor_id(), current->comm,
265 current->pid, lock);
266 dump_stack();
270 #endif
272 void do_raw_write_lock(rwlock_t *lock)
274 debug_write_lock_before(lock);
275 arch_write_lock(&lock->raw_lock);
276 debug_write_lock_after(lock);
279 int do_raw_write_trylock(rwlock_t *lock)
281 int ret = arch_write_trylock(&lock->raw_lock);
283 if (ret)
284 debug_write_lock_after(lock);
285 #ifndef CONFIG_SMP
287 * Must not happen on UP:
289 RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
290 #endif
291 return ret;
294 void do_raw_write_unlock(rwlock_t *lock)
296 debug_write_unlock(lock);
297 arch_write_unlock(&lock->raw_lock);