From d5abe669172f20a4129a711de0f250a4e07db298 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 6 Dec 2006 20:37:26 -0800 Subject: [PATCH] [PATCH] debug: workqueue locking sanity Workqueue functions should not leak locks, assert so, printing the last function ran. Use macros in lockdep.h to avoid include dependency pains. [akpm@osdl.org: build fix] Signed-off-by: Peter Zijlstra Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/lockdep.h | 5 +++++ kernel/workqueue.c | 13 +++++++++++++ 2 files changed, 18 insertions(+) diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 819f08f1310d..da19aeb0dbe8 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -243,6 +243,8 @@ extern void lock_release(struct lockdep_map *lock, int nested, # define INIT_LOCKDEP .lockdep_recursion = 0, +#define lockdep_depth(tsk) ((tsk)->lockdep_depth) + #else /* !LOCKDEP */ static inline void lockdep_off(void) @@ -277,6 +279,9 @@ static inline int lockdep_internal(void) * The class key takes no space if lockdep is disabled: */ struct lock_class_key { }; + +#define lockdep_depth(tsk) (0) + #endif /* !LOCKDEP */ #if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_GENERIC_HARDIRQS) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 2945b094d871..5484d6e045c2 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -30,6 +30,8 @@ #include #include #include +#include +#include /* * The per-CPU workqueue (if single thread, we always use the first @@ -253,6 +255,17 @@ static void run_workqueue(struct cpu_workqueue_struct *cwq) work_release(work); f(work); + if (unlikely(in_atomic() || lockdep_depth(current) > 0)) { + printk(KERN_ERR "BUG: workqueue leaked lock or atomic: " + "%s/0x%08x/%d\n", + current->comm, preempt_count(), + current->pid); + printk(KERN_ERR " last function: "); + print_symbol("%s\n", (unsigned long)f); + debug_show_held_locks(current); + dump_stack(); + } + spin_lock_irqsave(&cwq->lock, flags); cwq->remove_sequence++; wake_up(&cwq->work_done); -- 2.20.1