X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Flockdep.c;h=2594e1ce41cbf12889b44deb3fc202c0a5c30fa2;hb=5e8aa85253513b9c1ade8bd71dc341218a752a65;hp=f74d2d7aa605801f70209cc61f434bdfbc3a2663;hpb=a417887637e862b434b293404f2a31ad1f282a58;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/lockdep.c b/kernel/lockdep.c index f74d2d7..2594e1c 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -43,13 +43,14 @@ #include #include #include +#include #include #include "lockdep_internals.h" #define CREATE_TRACE_POINTS -#include +#include #ifdef CONFIG_PROVE_LOCKING int prove_locking = 1; @@ -73,11 +74,11 @@ module_param(lock_stat, int, 0644); * to use a raw spinlock - we really dont want the spinlock * code to recurse back into the lockdep code... */ -static raw_spinlock_t lockdep_lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; +static arch_spinlock_t lockdep_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; static int graph_lock(void) { - __raw_spin_lock(&lockdep_lock); + arch_spin_lock(&lockdep_lock); /* * Make sure that if another CPU detected a bug while * walking the graph we dont change it (while the other @@ -85,7 +86,7 @@ static int graph_lock(void) * dropped already) */ if (!debug_locks) { - __raw_spin_unlock(&lockdep_lock); + arch_spin_unlock(&lockdep_lock); return 0; } /* prevent any recursions within lockdep from causing deadlocks */ @@ -95,11 +96,11 @@ static int graph_lock(void) static inline int graph_unlock(void) { - if (debug_locks && !__raw_spin_is_locked(&lockdep_lock)) + if (debug_locks && !arch_spin_is_locked(&lockdep_lock)) return DEBUG_LOCKS_WARN_ON(1); current->lockdep_recursion--; - __raw_spin_unlock(&lockdep_lock); + arch_spin_unlock(&lockdep_lock); return 0; } @@ -111,7 +112,7 @@ static inline int debug_locks_off_graph_unlock(void) { int ret = debug_locks_off(); - __raw_spin_unlock(&lockdep_lock); + arch_spin_unlock(&lockdep_lock); return ret; } @@ -140,7 +141,13 @@ static inline struct lock_class *hlock_class(struct held_lock *hlock) } #ifdef CONFIG_LOCK_STAT -static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], lock_stats); +static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], + cpu_lock_stats); + +static inline u64 lockstat_clock(void) +{ + return cpu_clock(smp_processor_id()); +} static int lock_point(unsigned long points[], unsigned long ip) { @@ -158,12 +165,12 @@ static int lock_point(unsigned long points[], unsigned long ip) return i; } -static void lock_time_inc(struct lock_time *lt, s64 time) +static void lock_time_inc(struct lock_time *lt, u64 time) { if (time > lt->max) lt->max = time; - if (time < lt->min || !lt->min) + if (time < lt->min || !lt->nr) lt->min = time; lt->total += time; @@ -172,8 +179,15 @@ static void lock_time_inc(struct lock_time *lt, s64 time) static inline void lock_time_add(struct lock_time *src, struct lock_time *dst) { - dst->min += src->min; - dst->max += src->max; + if (!src->nr) + return; + + if (src->max > dst->max) + dst->max = src->max; + + if (src->min < dst->min || !dst->nr) + dst->min = src->min; + dst->total += src->total; dst->nr += src->nr; } @@ -186,7 +200,7 @@ struct lock_class_stats lock_stats(struct lock_class *class) memset(&stats, 0, sizeof(struct lock_class_stats)); for_each_possible_cpu(cpu) { struct lock_class_stats *pcs = - &per_cpu(lock_stats, cpu)[class - lock_classes]; + &per_cpu(cpu_lock_stats, cpu)[class - lock_classes]; for (i = 0; i < ARRAY_SIZE(stats.contention_point); i++) stats.contention_point[i] += pcs->contention_point[i]; @@ -213,7 +227,7 @@ void clear_lock_stats(struct lock_class *class) for_each_possible_cpu(cpu) { struct lock_class_stats *cpu_stats = - &per_cpu(lock_stats, cpu)[class - lock_classes]; + &per_cpu(cpu_lock_stats, cpu)[class - lock_classes]; memset(cpu_stats, 0, sizeof(struct lock_class_stats)); } @@ -223,23 +237,23 @@ void clear_lock_stats(struct lock_class *class) static struct lock_class_stats *get_lock_stats(struct lock_class *class) { - return &get_cpu_var(lock_stats)[class - lock_classes]; + return &get_cpu_var(cpu_lock_stats)[class - lock_classes]; } static void put_lock_stats(struct lock_class_stats *stats) { - put_cpu_var(lock_stats); + put_cpu_var(cpu_lock_stats); } static void lock_release_holdtime(struct held_lock *hlock) { struct lock_class_stats *stats; - s64 holdtime; + u64 holdtime; if (!lock_stat) return; - holdtime = sched_clock() - hlock->holdtime_stamp; + holdtime = lockstat_clock() - hlock->holdtime_stamp; stats = get_lock_stats(hlock_class(hlock)); if (hlock->read) @@ -374,7 +388,8 @@ static int save_trace(struct stack_trace *trace) * complete trace that maxes out the entries provided will be reported * as incomplete, friggin useless */ - if (trace->entries[trace->nr_entries-1] == ULONG_MAX) + if (trace->nr_entries != 0 && + trace->entries[trace->nr_entries-1] == ULONG_MAX) trace->nr_entries--; trace->max_entries = trace->nr_entries; @@ -568,9 +583,6 @@ static int static_obj(void *obj) unsigned long start = (unsigned long) &_stext, end = (unsigned long) &_end, addr = (unsigned long) obj; -#ifdef CONFIG_SMP - int i; -#endif /* * static variable? @@ -578,24 +590,19 @@ static int static_obj(void *obj) if ((addr >= start) && (addr < end)) return 1; -#ifdef CONFIG_SMP + if (arch_is_kernel_data(addr)) + return 1; + /* - * percpu var? + * in-kernel percpu var? */ - for_each_possible_cpu(i) { - start = (unsigned long) &__per_cpu_start + per_cpu_offset(i); - end = (unsigned long) &__per_cpu_start + PERCPU_ENOUGH_ROOM - + per_cpu_offset(i); - - if ((addr >= start) && (addr < end)) - return 1; - } -#endif + if (is_kernel_percpu_address(addr)) + return 1; /* - * module var? + * module static or percpu var? */ - return is_module_address(addr); + return is_module_address(addr) || is_module_percpu_address(addr); } /* @@ -1153,9 +1160,9 @@ unsigned long lockdep_count_forward_deps(struct lock_class *class) this.class = class; local_irq_save(flags); - __raw_spin_lock(&lockdep_lock); + arch_spin_lock(&lockdep_lock); ret = __lockdep_count_forward_deps(&this); - __raw_spin_unlock(&lockdep_lock); + arch_spin_unlock(&lockdep_lock); local_irq_restore(flags); return ret; @@ -1180,9 +1187,9 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class) this.class = class; local_irq_save(flags); - __raw_spin_lock(&lockdep_lock); + arch_spin_lock(&lockdep_lock); ret = __lockdep_count_backward_deps(&this); - __raw_spin_unlock(&lockdep_lock); + arch_spin_unlock(&lockdep_lock); local_irq_restore(flags); return ret; @@ -2130,7 +2137,7 @@ check_usage_backwards(struct task_struct *curr, struct held_lock *this, return ret; return print_irq_inversion_bug(curr, &root, target_entry, - this, 1, irqclass); + this, 0, irqclass); } void print_irqtrace_events(struct task_struct *curr) @@ -2789,7 +2796,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, hlock->references = references; #ifdef CONFIG_LOCK_STAT hlock->waittime_stamp = 0; - hlock->holdtime_stamp = sched_clock(); + hlock->holdtime_stamp = lockstat_clock(); #endif if (check == 2 && !mark_irqflags(curr, hlock)) @@ -3194,8 +3201,6 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass, { unsigned long flags; - trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip); - if (unlikely(current->lockdep_recursion)) return; @@ -3203,6 +3208,7 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass, check_flags(flags); current->lockdep_recursion = 1; + trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip); __lock_acquire(lock, subclass, trylock, read, check, irqs_disabled_flags(flags), nest_lock, ip, 0); current->lockdep_recursion = 0; @@ -3215,14 +3221,13 @@ void lock_release(struct lockdep_map *lock, int nested, { unsigned long flags; - trace_lock_release(lock, nested, ip); - if (unlikely(current->lockdep_recursion)) return; raw_local_irq_save(flags); check_flags(flags); current->lockdep_recursion = 1; + trace_lock_release(lock, nested, ip); __lock_release(lock, nested, ip); current->lockdep_recursion = 0; raw_local_irq_restore(flags); @@ -3319,7 +3324,7 @@ found_it: if (hlock->instance != lock) return; - hlock->waittime_stamp = sched_clock(); + hlock->waittime_stamp = lockstat_clock(); contention_point = lock_point(hlock_class(hlock)->contention_point, ip); contending_point = lock_point(hlock_class(hlock)->contending_point, @@ -3342,8 +3347,7 @@ __lock_acquired(struct lockdep_map *lock, unsigned long ip) struct held_lock *hlock, *prev_hlock; struct lock_class_stats *stats; unsigned int depth; - u64 now; - s64 waittime = 0; + u64 now, waittime = 0; int i, cpu; depth = curr->lockdep_depth; @@ -3371,7 +3375,7 @@ found_it: cpu = smp_processor_id(); if (hlock->waittime_stamp) { - now = sched_clock(); + now = lockstat_clock(); waittime = now - hlock->waittime_stamp; hlock->holdtime_stamp = now; } @@ -3397,8 +3401,6 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip) { unsigned long flags; - trace_lock_contended(lock, ip); - if (unlikely(!lock_stat)) return; @@ -3408,6 +3410,7 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip) raw_local_irq_save(flags); check_flags(flags); current->lockdep_recursion = 1; + trace_lock_contended(lock, ip); __lock_contended(lock, ip); current->lockdep_recursion = 0; raw_local_irq_restore(flags); @@ -3793,3 +3796,22 @@ void lockdep_sys_exit(void) lockdep_print_held_locks(curr); } } + +void lockdep_rcu_dereference(const char *file, const int line) +{ + struct task_struct *curr = current; + + if (!debug_locks_off()) + return; + printk("\n===================================================\n"); + printk( "[ INFO: suspicious rcu_dereference_check() usage. ]\n"); + printk( "---------------------------------------------------\n"); + printk("%s:%d invoked rcu_dereference_check() without protection!\n", + file, line); + printk("\nother info that might help us debug this:\n\n"); + printk("\nrcu_scheduler_active = %d, debug_locks = %d\n", rcu_scheduler_active, debug_locks); + lockdep_print_held_locks(curr); + printk("\nstack backtrace:\n"); + dump_stack(); +} +EXPORT_SYMBOL_GPL(lockdep_rcu_dereference);