diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/dump_stack.c | 47 | ||||
| -rw-r--r-- | lib/idr.c | 7 | ||||
| -rw-r--r-- | lib/percpu_counter.c | 2 |
3 files changed, 48 insertions, 8 deletions
diff --git a/lib/dump_stack.c b/lib/dump_stack.c index 53bad099ebd6..c03154173cc7 100644 --- a/lib/dump_stack.c +++ b/lib/dump_stack.c @@ -6,15 +6,58 @@ #include <linux/kernel.h> #include <linux/export.h> #include <linux/sched.h> +#include <linux/smp.h> +#include <linux/atomic.h> + +static void __dump_stack(void) +{ + dump_stack_print_info(KERN_DEFAULT); + show_stack(NULL, NULL); +} /** * dump_stack - dump the current task information and its stack trace * * Architectures can override this implementation by implementing its own. */ +#ifdef CONFIG_SMP +static atomic_t dump_lock = ATOMIC_INIT(-1); + void dump_stack(void) { - dump_stack_print_info(KERN_DEFAULT); - show_stack(NULL, NULL); + int was_locked; + int old; + int cpu; + + /* + * Permit this cpu to perform nested stack dumps while serialising + * against other CPUs + */ + preempt_disable(); + +retry: + cpu = smp_processor_id(); + old = atomic_cmpxchg(&dump_lock, -1, cpu); + if (old == -1) { + was_locked = 0; + } else if (old == cpu) { + was_locked = 1; + } else { + cpu_relax(); + goto retry; + } + + __dump_stack(); + + if (!was_locked) + atomic_set(&dump_lock, -1); + + preempt_enable(); +} +#else +void dump_stack(void) +{ + __dump_stack(); } +#endif EXPORT_SYMBOL(dump_stack); diff --git a/lib/idr.c b/lib/idr.c index cca4b9302a71..bfe4db4e165f 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -524,9 +524,7 @@ EXPORT_SYMBOL(idr_alloc_cyclic); static void idr_remove_warning(int id) { - printk(KERN_WARNING - "idr_remove called for id=%d which is not allocated.\n", id); - dump_stack(); + WARN(1, "idr_remove called for id=%d which is not allocated.\n", id); } static void sub_remove(struct idr *idp, int shift, int id) @@ -1064,8 +1062,7 @@ void ida_remove(struct ida *ida, int id) return; err: - printk(KERN_WARNING - "ida_remove called for id=%d which is not allocated.\n", id); + WARN(1, "ida_remove called for id=%d which is not allocated.\n", id); } EXPORT_SYMBOL(ida_remove); diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c index ba6085d9c741..1fc23a3277e1 100644 --- a/lib/percpu_counter.c +++ b/lib/percpu_counter.c @@ -80,8 +80,8 @@ void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch) if (count >= batch || count <= -batch) { raw_spin_lock(&fbc->lock); fbc->count += count; - __this_cpu_write(*fbc->counters, 0); raw_spin_unlock(&fbc->lock); + __this_cpu_write(*fbc->counters, 0); } else { __this_cpu_write(*fbc->counters, count); } |