diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig.debug | 14 | ||||
| -rw-r--r-- | lib/btree.c | 3 | ||||
| -rw-r--r-- | lib/debugobjects.c | 63 | ||||
| -rw-r--r-- | lib/rwsem.c | 5 |
4 files changed, 76 insertions, 9 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 231384012a14..d85be90d5888 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -512,6 +512,18 @@ config PROVE_RCU Say N if you are unsure. +config PROVE_RCU_REPEATEDLY + bool "RCU debugging: don't disable PROVE_RCU on first splat" + depends on PROVE_RCU + default n + help + By itself, PROVE_RCU will disable checking upon issuing the + first warning (or "splat"). This feature prevents such + disabling, allowing multiple RCU-lockdep warnings to be printed + on a single reboot. + + Say N if you are unsure. + config LOCKDEP bool depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT @@ -793,7 +805,7 @@ config RCU_CPU_STALL_DETECTOR config RCU_CPU_STALL_VERBOSE bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR" depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_RCU - default n + default y help This option causes RCU to printk detailed per-task information for any tasks that are stalling the current RCU grace period. diff --git a/lib/btree.c b/lib/btree.c index 41859a820218..c9c6f0351526 100644 --- a/lib/btree.c +++ b/lib/btree.c @@ -95,7 +95,8 @@ static unsigned long *btree_node_alloc(struct btree_head *head, gfp_t gfp) unsigned long *node; node = mempool_alloc(head->mempool, gfp); - memset(node, 0, NODESIZE); + if (likely(node)) + memset(node, 0, NODESIZE); return node; } diff --git a/lib/debugobjects.c b/lib/debugobjects.c index b862b30369ff..deebcc57d4e6 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -141,6 +141,7 @@ alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) obj->object = addr; obj->descr = descr; obj->state = ODEBUG_STATE_NONE; + obj->astate = 0; hlist_del(&obj->node); hlist_add_head(&obj->node, &b->list); @@ -252,8 +253,10 @@ static void debug_print_object(struct debug_obj *obj, char *msg) if (limit < 5 && obj->descr != descr_test) { limit++; - WARN(1, KERN_ERR "ODEBUG: %s %s object type: %s\n", msg, - obj_states[obj->state], obj->descr->name); + WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) " + "object type: %s\n", + msg, obj_states[obj->state], obj->astate, + obj->descr->name); } debug_objects_warnings++; } @@ -447,7 +450,10 @@ void debug_object_deactivate(void *addr, struct debug_obj_descr *descr) case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: case ODEBUG_STATE_ACTIVE: - obj->state = ODEBUG_STATE_INACTIVE; + if (!obj->astate) + obj->state = ODEBUG_STATE_INACTIVE; + else + debug_print_object(obj, "deactivate"); break; case ODEBUG_STATE_DESTROYED: @@ -553,6 +559,53 @@ out_unlock: raw_spin_unlock_irqrestore(&db->lock, flags); } +/** + * debug_object_active_state - debug checks object usage state machine + * @addr: address of the object + * @descr: pointer to an object specific debug description structure + * @expect: expected state + * @next: state to move to if expected state is found + */ +void +debug_object_active_state(void *addr, struct debug_obj_descr *descr, + unsigned int expect, unsigned int next) +{ + struct debug_bucket *db; + struct debug_obj *obj; + unsigned long flags; + + if (!debug_objects_enabled) + return; + + db = get_bucket((unsigned long) addr); + + raw_spin_lock_irqsave(&db->lock, flags); + + obj = lookup_object(addr, db); + if (obj) { + switch (obj->state) { + case ODEBUG_STATE_ACTIVE: + if (obj->astate == expect) + obj->astate = next; + else + debug_print_object(obj, "active_state"); + break; + + default: + debug_print_object(obj, "active_state"); + break; + } + } else { + struct debug_obj o = { .object = addr, + .state = ODEBUG_STATE_NOTAVAILABLE, + .descr = descr }; + + debug_print_object(&o, "active_state"); + } + + raw_spin_unlock_irqrestore(&db->lock, flags); +} + #ifdef CONFIG_DEBUG_OBJECTS_FREE static void __debug_check_no_obj_freed(const void *address, unsigned long size) { @@ -774,7 +827,7 @@ static int __init fixup_free(void *addr, enum debug_obj_state state) } } -static int +static int __init check_results(void *addr, enum debug_obj_state state, int fixups, int warnings) { struct debug_bucket *db; @@ -917,7 +970,7 @@ void __init debug_objects_early_init(void) /* * Convert the statically allocated objects to dynamic ones: */ -static int debug_objects_replace_static_objects(void) +static int __init debug_objects_replace_static_objects(void) { struct debug_bucket *db = obj_hash; struct hlist_node *node, *tmp; diff --git a/lib/rwsem.c b/lib/rwsem.c index 3e3365e5665e..ceba8e28807a 100644 --- a/lib/rwsem.c +++ b/lib/rwsem.c @@ -136,9 +136,10 @@ __rwsem_do_wake(struct rw_semaphore *sem, int downgrading) out: return sem; - /* undo the change to count, but check for a transition 1->0 */ + /* undo the change to the active count, but check for a transition + * 1->0 */ undo: - if (rwsem_atomic_update(-RWSEM_ACTIVE_BIAS, sem) != 0) + if (rwsem_atomic_update(-RWSEM_ACTIVE_BIAS, sem) & RWSEM_ACTIVE_MASK) goto out; goto try_again; } |