diff options
Diffstat (limited to 'kernel/rtmutex-debug.c')
| -rw-r--r-- | kernel/rtmutex-debug.c | 120 |
1 files changed, 33 insertions, 87 deletions
diff --git a/kernel/rtmutex-debug.c b/kernel/rtmutex-debug.c index da8d6bf46457..13b243a323fa 100644 --- a/kernel/rtmutex-debug.c +++ b/kernel/rtmutex-debug.c @@ -17,8 +17,9 @@ * See rt.c in preempt-rt for proper credits and further information */ #include <linux/sched.h> +#include <linux/sched/rt.h> #include <linux/delay.h> -#include <linux/module.h> +#include <linux/export.h> #include <linux/spinlock.h> #include <linux/kallsyms.h> #include <linux/syscalls.h> @@ -29,76 +30,10 @@ #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) - -# define TRACE_OFF() \ -do { \ - if (rt_trace_on) { \ - rt_trace_on = 0; \ - console_verbose(); \ - if (spin_is_locked(¤t->pi_lock)) \ - spin_unlock(¤t->pi_lock); \ - } \ -} while (0) - -# define TRACE_OFF_NOLOCK() \ -do { \ - if (rt_trace_on) { \ - rt_trace_on = 0; \ - console_verbose(); \ - } \ -} while (0) - -# define TRACE_BUG_LOCKED() \ -do { \ - TRACE_OFF(); \ - BUG(); \ -} while (0) - -# define TRACE_WARN_ON_LOCKED(c) \ -do { \ - if (unlikely(c)) { \ - TRACE_OFF(); \ - WARN_ON(1); \ - } \ -} while (0) - -# define TRACE_BUG_ON_LOCKED(c) \ -do { \ - if (unlikely(c)) \ - TRACE_BUG_LOCKED(); \ -} while (0) - -#ifdef CONFIG_SMP -# define SMP_TRACE_BUG_ON_LOCKED(c) TRACE_BUG_ON_LOCKED(c) -#else -# define SMP_TRACE_BUG_ON_LOCKED(c) do { } while (0) -#endif - -/* - * deadlock detection flag. We turn it off when we detect - * the first problem because we dont want to recurse back - * 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(struct task_struct *p) { if (p) - printk("%16s:%5d [%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("<none>"); } @@ -122,8 +57,8 @@ static void printk_lock(struct rt_mutex *lock, int print_owner) void rt_mutex_debug_task_free(struct task_struct *task) { - WARN_ON(!plist_head_empty(&task->pi_waiters)); - WARN_ON(task->pi_blocked_on); + DEBUG_LOCKS_WARN_ON(!plist_head_empty(&task->pi_waiters)); + DEBUG_LOCKS_WARN_ON(task->pi_blocked_on); } /* @@ -136,12 +71,12 @@ void debug_rt_mutex_deadlock(int detect, struct rt_mutex_waiter *act_waiter, { struct task_struct *task; - if (!rt_trace_on || detect || !act_waiter) + if (!debug_locks || detect || !act_waiter) return; 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; } } @@ -150,41 +85,51 @@ void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter) { struct task_struct *task; - if (!waiter->deadlock_lock || !rt_trace_on) + if (!waiter->deadlock_lock || !debug_locks) 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(); + if (!debug_locks_off()) { + rcu_read_unlock(); + return; + } printk("\n============================================\n"); printk( "[ BUG: circular locking deadlock detected! ]\n"); + printk("%s\n", print_tainted()); 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("\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); 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(); 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) @@ -193,7 +138,7 @@ void debug_rt_mutex_lock(struct rt_mutex *lock) void debug_rt_mutex_unlock(struct rt_mutex *lock) { - TRACE_WARN_ON_LOCKED(rt_mutex_owner(lock) != current); + DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) != current); } void @@ -203,7 +148,7 @@ debug_rt_mutex_proxy_lock(struct rt_mutex *lock, struct task_struct *powner) void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock) { - TRACE_WARN_ON_LOCKED(!rt_mutex_owner(lock)); + DEBUG_LOCKS_WARN_ON(!rt_mutex_owner(lock)); } void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter) @@ -211,13 +156,14 @@ 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) { - TRACE_WARN_ON(!plist_node_empty(&waiter->list_entry)); - TRACE_WARN_ON(!plist_node_empty(&waiter->pi_list_entry)); - TRACE_WARN_ON(waiter->task); + put_pid(waiter->deadlock_task_pid); + DEBUG_LOCKS_WARN_ON(!plist_node_empty(&waiter->list_entry)); + DEBUG_LOCKS_WARN_ON(!plist_node_empty(&waiter->pi_list_entry)); memset(waiter, 0x22, sizeof(*waiter)); } |