X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Frtmutex-debug.c;h=5fcb4fe645e245a4a6c043aedbf1c212dbefadf0;hb=efb9a8c28ca0edd9e2572117105ebad9bbc0c368;hp=4aa8a2c9f45341935827b904b1aa27b74b5fc8c8;hpb=e7eebaf6a81b956c989f184ee4b27277c88f8afe;p=linux-2.6-omap-h63xx.git diff --git a/kernel/rtmutex-debug.c b/kernel/rtmutex-debug.c index 4aa8a2c9f45..5fcb4fe645e 100644 --- a/kernel/rtmutex-debug.c +++ b/kernel/rtmutex-debug.c @@ -16,7 +16,6 @@ * * See rt.c in preempt-rt for proper credits and further information */ -#include #include #include #include @@ -26,15 +25,10 @@ #include #include #include +#include #include "rtmutex_common.h" -#ifdef CONFIG_DEBUG_RT_MUTEXES -# include "rtmutex-debug.h" -#else -# include "rtmutex.h" -#endif - # define TRACE_WARN_ON(x) WARN_ON(x) # define TRACE_BUG_ON(x) BUG_ON(x) @@ -45,8 +39,6 @@ do { \ console_verbose(); \ if (spin_is_locked(¤t->pi_lock)) \ spin_unlock(¤t->pi_lock); \ - if (spin_is_locked(¤t->held_list_lock)) \ - spin_unlock(¤t->held_list_lock); \ } \ } while (0) @@ -90,25 +82,12 @@ do { \ * into the tracing code when doing error printk or * executing a BUG(): */ -int rt_trace_on = 1; - -void deadlock_trace_off(void) -{ - rt_trace_on = 0; -} - -static void printk_task(task_t *p) -{ - if (p) - printk("%16s:%5d [%p, %3d]", p->comm, p->pid, p, p->prio); - else - printk(""); -} +static int rt_trace_on = 1; -static void printk_task_short(task_t *p) +static void printk_task(struct task_struct *p) { if (p) - printk("%s/%d [%p, %3d]", p->comm, p->pid, p, p->prio); + printk("%16s:%5d [%p, %3d]", p->comm, task_pid_nr(p), p, p->prio); else printk(""); } @@ -128,222 +107,6 @@ static void printk_lock(struct rt_mutex *lock, int print_owner) printk_task(rt_mutex_owner(lock)); printk("\n"); } - if (rt_mutex_owner(lock)) { - printk("... acquired at: "); - print_symbol("%s\n", lock->acquire_ip); - } -} - -static void printk_waiter(struct rt_mutex_waiter *w) -{ - printk("-------------------------\n"); - printk("| waiter struct %p:\n", w); - printk("| w->list_entry: [DP:%p/%p|SP:%p/%p|PRI:%d]\n", - w->list_entry.plist.prio_list.prev, w->list_entry.plist.prio_list.next, - w->list_entry.plist.node_list.prev, w->list_entry.plist.node_list.next, - w->list_entry.prio); - printk("| w->pi_list_entry: [DP:%p/%p|SP:%p/%p|PRI:%d]\n", - w->pi_list_entry.plist.prio_list.prev, w->pi_list_entry.plist.prio_list.next, - w->pi_list_entry.plist.node_list.prev, w->pi_list_entry.plist.node_list.next, - w->pi_list_entry.prio); - printk("\n| lock:\n"); - printk_lock(w->lock, 1); - printk("| w->ti->task:\n"); - printk_task(w->task); - printk("| blocked at: "); - print_symbol("%s\n", w->ip); - printk("-------------------------\n"); -} - -static void show_task_locks(task_t *p) -{ - switch (p->state) { - case TASK_RUNNING: printk("R"); break; - case TASK_INTERRUPTIBLE: printk("S"); break; - case TASK_UNINTERRUPTIBLE: printk("D"); break; - case TASK_STOPPED: printk("T"); break; - case EXIT_ZOMBIE: printk("Z"); break; - case EXIT_DEAD: printk("X"); break; - default: printk("?"); break; - } - printk_task(p); - if (p->pi_blocked_on) { - struct rt_mutex *lock = p->pi_blocked_on->lock; - - printk(" blocked on:"); - printk_lock(lock, 1); - } else - printk(" (not blocked)\n"); -} - -void rt_mutex_show_held_locks(task_t *task, int verbose) -{ - struct list_head *curr, *cursor = NULL; - struct rt_mutex *lock; - task_t *t; - unsigned long flags; - int count = 0; - - if (!rt_trace_on) - return; - - if (verbose) { - printk("------------------------------\n"); - printk("| showing all locks held by: | ("); - printk_task_short(task); - printk("):\n"); - printk("------------------------------\n"); - } - -next: - spin_lock_irqsave(&task->held_list_lock, flags); - list_for_each(curr, &task->held_list_head) { - if (cursor && curr != cursor) - continue; - lock = list_entry(curr, struct rt_mutex, held_list_entry); - t = rt_mutex_owner(lock); - WARN_ON(t != task); - count++; - cursor = curr->next; - spin_unlock_irqrestore(&task->held_list_lock, flags); - - printk("\n#%03d: ", count); - printk_lock(lock, 0); - goto next; - } - spin_unlock_irqrestore(&task->held_list_lock, flags); - - printk("\n"); -} - -void rt_mutex_show_all_locks(void) -{ - task_t *g, *p; - int count = 10; - int unlock = 1; - - printk("\n"); - printk("----------------------\n"); - printk("| showing all tasks: |\n"); - printk("----------------------\n"); - - /* - * Here we try to get the tasklist_lock as hard as possible, - * if not successful after 2 seconds we ignore it (but keep - * trying). This is to enable a debug printout even if a - * tasklist_lock-holding task deadlocks or crashes. - */ -retry: - if (!read_trylock(&tasklist_lock)) { - if (count == 10) - printk("hm, tasklist_lock locked, retrying... "); - if (count) { - count--; - printk(" #%d", 10-count); - mdelay(200); - goto retry; - } - printk(" ignoring it.\n"); - unlock = 0; - } - if (count != 10) - printk(" locked it.\n"); - - do_each_thread(g, p) { - show_task_locks(p); - if (!unlock) - if (read_trylock(&tasklist_lock)) - unlock = 1; - } while_each_thread(g, p); - - printk("\n"); - - printk("-----------------------------------------\n"); - printk("| showing all locks held in the system: |\n"); - printk("-----------------------------------------\n"); - - do_each_thread(g, p) { - rt_mutex_show_held_locks(p, 0); - if (!unlock) - if (read_trylock(&tasklist_lock)) - unlock = 1; - } while_each_thread(g, p); - - - printk("=============================================\n\n"); - - if (unlock) - read_unlock(&tasklist_lock); -} - -void rt_mutex_debug_check_no_locks_held(task_t *task) -{ - struct rt_mutex_waiter *w; - struct list_head *curr; - struct rt_mutex *lock; - - if (!rt_trace_on) - return; - if (!rt_prio(task->normal_prio) && rt_prio(task->prio)) { - printk("BUG: PI priority boost leaked!\n"); - printk_task(task); - printk("\n"); - } - if (list_empty(&task->held_list_head)) - return; - - spin_lock(&task->pi_lock); - plist_for_each_entry(w, &task->pi_waiters, pi_list_entry) { - TRACE_OFF(); - - printk("hm, PI interest held at exit time? Task:\n"); - printk_task(task); - printk_waiter(w); - return; - } - spin_unlock(&task->pi_lock); - - list_for_each(curr, &task->held_list_head) { - lock = list_entry(curr, struct rt_mutex, held_list_entry); - - printk("BUG: %s/%d, lock held at task exit time!\n", - task->comm, task->pid); - printk_lock(lock, 1); - if (rt_mutex_owner(lock) != task) - printk("exiting task is not even the owner??\n"); - } -} - -int rt_mutex_debug_check_no_locks_freed(const void *from, unsigned long len) -{ - const void *to = from + len; - struct list_head *curr; - struct rt_mutex *lock; - unsigned long flags; - void *lock_addr; - - if (!rt_trace_on) - return 0; - - spin_lock_irqsave(¤t->held_list_lock, flags); - list_for_each(curr, ¤t->held_list_head) { - lock = list_entry(curr, struct rt_mutex, held_list_entry); - lock_addr = lock; - if (lock_addr < from || lock_addr >= to) - continue; - TRACE_OFF(); - - printk("BUG: %s/%d, active lock [%p(%p-%p)] freed!\n", - current->comm, current->pid, lock, from, to); - dump_stack(); - printk_lock(lock, 1); - if (rt_mutex_owner(lock) != current) - printk("freeing task is not even the owner??\n"); - return 1; - } - spin_unlock_irqrestore(¤t->held_list_lock, flags); - - return 0; } void rt_mutex_debug_task_free(struct task_struct *task) @@ -367,7 +130,7 @@ void debug_rt_mutex_deadlock(int detect, struct rt_mutex_waiter *act_waiter, task = rt_mutex_owner(act_waiter->lock); if (task && task != current) { - act_waiter->deadlock_task_pid = task->pid; + act_waiter->deadlock_task_pid = get_pid(task_pid(task)); act_waiter->deadlock_lock = lock; } } @@ -379,9 +142,12 @@ void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter) if (!waiter->deadlock_lock || !rt_trace_on) return; - task = find_task_by_pid(waiter->deadlock_task_pid); - if (!task) + rcu_read_lock(); + task = pid_task(waiter->deadlock_task_pid, PIDTYPE_PID); + if (!task) { + rcu_read_unlock(); return; + } TRACE_OFF_NOLOCK(); @@ -389,91 +155,51 @@ void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter) printk( "[ BUG: circular locking deadlock detected! ]\n"); printk( "--------------------------------------------\n"); printk("%s/%d is deadlocking current task %s/%d\n\n", - task->comm, task->pid, current->comm, current->pid); + task->comm, task_pid_nr(task), + current->comm, task_pid_nr(current)); printk("\n1) %s/%d is trying to acquire this lock:\n", - current->comm, current->pid); + current->comm, task_pid_nr(current)); printk_lock(waiter->lock, 1); - printk("... trying at: "); - print_symbol("%s\n", waiter->ip); - - printk("\n2) %s/%d is blocked on this lock:\n", task->comm, task->pid); + printk("\n2) %s/%d is blocked on this lock:\n", + task->comm, task_pid_nr(task)); printk_lock(waiter->deadlock_lock, 1); - rt_mutex_show_held_locks(current, 1); - rt_mutex_show_held_locks(task, 1); + debug_show_held_locks(current); + debug_show_held_locks(task); - printk("\n%s/%d's [blocked] stackdump:\n\n", task->comm, task->pid); + printk("\n%s/%d's [blocked] stackdump:\n\n", + task->comm, task_pid_nr(task)); show_stack(task, NULL); printk("\n%s/%d's [current] stackdump:\n\n", - current->comm, current->pid); + current->comm, task_pid_nr(current)); dump_stack(); - rt_mutex_show_all_locks(); + debug_show_all_locks(); + rcu_read_unlock(); + printk("[ turning off deadlock detection." "Please report this trace. ]\n\n"); local_irq_disable(); } -void debug_rt_mutex_lock(struct rt_mutex *lock __IP_DECL__) +void debug_rt_mutex_lock(struct rt_mutex *lock) { - unsigned long flags; - - if (rt_trace_on) { - TRACE_WARN_ON_LOCKED(!list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(¤t->held_list_lock, flags); - list_add_tail(&lock->held_list_entry, ¤t->held_list_head); - spin_unlock_irqrestore(¤t->held_list_lock, flags); - - lock->acquire_ip = ip; - } } void debug_rt_mutex_unlock(struct rt_mutex *lock) { - unsigned long flags; - - if (rt_trace_on) { - TRACE_WARN_ON_LOCKED(rt_mutex_owner(lock) != current); - TRACE_WARN_ON_LOCKED(list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(¤t->held_list_lock, flags); - list_del_init(&lock->held_list_entry); - spin_unlock_irqrestore(¤t->held_list_lock, flags); - } + TRACE_WARN_ON_LOCKED(rt_mutex_owner(lock) != current); } -void debug_rt_mutex_proxy_lock(struct rt_mutex *lock, - struct task_struct *powner __IP_DECL__) +void +debug_rt_mutex_proxy_lock(struct rt_mutex *lock, struct task_struct *powner) { - unsigned long flags; - - if (rt_trace_on) { - TRACE_WARN_ON_LOCKED(!list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(&powner->held_list_lock, flags); - list_add_tail(&lock->held_list_entry, &powner->held_list_head); - spin_unlock_irqrestore(&powner->held_list_lock, flags); - - lock->acquire_ip = ip; - } } void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock) { - unsigned long flags; - - if (rt_trace_on) { - struct task_struct *owner = rt_mutex_owner(lock); - - TRACE_WARN_ON_LOCKED(!owner); - TRACE_WARN_ON_LOCKED(list_empty(&lock->held_list_entry)); - - spin_lock_irqsave(&owner->held_list_lock, flags); - list_del_init(&lock->held_list_entry); - spin_unlock_irqrestore(&owner->held_list_lock, flags); - } + TRACE_WARN_ON_LOCKED(!rt_mutex_owner(lock)); } void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter) @@ -481,10 +207,12 @@ void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter) memset(waiter, 0x11, sizeof(*waiter)); plist_node_init(&waiter->list_entry, MAX_PRIO); plist_node_init(&waiter->pi_list_entry, MAX_PRIO); + waiter->deadlock_task_pid = NULL; } void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter) { + put_pid(waiter->deadlock_task_pid); TRACE_WARN_ON(!plist_node_empty(&waiter->list_entry)); TRACE_WARN_ON(!plist_node_empty(&waiter->pi_list_entry)); TRACE_WARN_ON(waiter->task); @@ -493,17 +221,15 @@ void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter) void debug_rt_mutex_init(struct rt_mutex *lock, const char *name) { - void *addr = lock; - - if (rt_trace_on) { - rt_mutex_debug_check_no_locks_freed(addr, - sizeof(struct rt_mutex)); - INIT_LIST_HEAD(&lock->held_list_entry); - lock->name = name; - } + /* + * Make sure we are not reinitializing a held lock: + */ + debug_check_no_locks_freed((void *)lock, sizeof(*lock)); + lock->name = name; } -void rt_mutex_deadlock_account_lock(struct rt_mutex *lock, task_t *task) +void +rt_mutex_deadlock_account_lock(struct rt_mutex *lock, struct task_struct *task) { }