From 9999e48639b3cecb08ffb37358bcba3b48161b29 Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Fri, 10 May 2024 08:50:17 +0000 Subject: [PATCH] add ax88772_rst --- kernel/lib/debugobjects.c | 574 ++++++++++++++++++++++++++++++++++++++++---------------- 1 files changed, 406 insertions(+), 168 deletions(-) diff --git a/kernel/lib/debugobjects.c b/kernel/lib/debugobjects.c index e28481c..4dd9283 100644 --- a/kernel/lib/debugobjects.c +++ b/kernel/lib/debugobjects.c @@ -19,21 +19,43 @@ #include <linux/slab.h> #include <linux/hash.h> #include <linux/kmemleak.h> +#include <linux/cpu.h> #define ODEBUG_HASH_BITS 14 #define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS) #define ODEBUG_POOL_SIZE 1024 #define ODEBUG_POOL_MIN_LEVEL 256 +#define ODEBUG_POOL_PERCPU_SIZE 64 +#define ODEBUG_BATCH_SIZE 16 #define ODEBUG_CHUNK_SHIFT PAGE_SHIFT #define ODEBUG_CHUNK_SIZE (1 << ODEBUG_CHUNK_SHIFT) #define ODEBUG_CHUNK_MASK (~(ODEBUG_CHUNK_SIZE - 1)) +/* + * We limit the freeing of debug objects via workqueue at a maximum + * frequency of 10Hz and about 1024 objects for each freeing operation. + * So it is freeing at most 10k debug objects per second. + */ +#define ODEBUG_FREE_WORK_MAX 1024 +#define ODEBUG_FREE_WORK_DELAY DIV_ROUND_UP(HZ, 10) + struct debug_bucket { struct hlist_head list; raw_spinlock_t lock; }; + +/* + * Debug object percpu free list + * Access is protected by disabling irq + */ +struct debug_percpu_free { + struct hlist_head free_objs; + int obj_free; +}; + +static DEFINE_PER_CPU(struct debug_percpu_free, percpu_obj_pool); static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE]; @@ -44,13 +66,20 @@ static HLIST_HEAD(obj_pool); static HLIST_HEAD(obj_to_free); +/* + * Because of the presence of percpu free pools, obj_pool_free will + * under-count those in the percpu free pools. Similarly, obj_pool_used + * will over-count those in the percpu free pools. Adjustments will be + * made at debug_stats_show(). Both obj_pool_min_free and obj_pool_max_used + * can be off. + */ static int obj_pool_min_free = ODEBUG_POOL_SIZE; static int obj_pool_free = ODEBUG_POOL_SIZE; static int obj_pool_used; static int obj_pool_max_used; +static bool obj_freeing; /* The number of objs on the global free list */ static int obj_nr_tofree; -static struct kmem_cache *obj_cache; static int debug_objects_maxchain __read_mostly; static int __maybe_unused debug_objects_maxchecked __read_mostly; @@ -62,7 +91,8 @@ = ODEBUG_POOL_SIZE; static int debug_objects_pool_min_level __read_mostly = ODEBUG_POOL_MIN_LEVEL; -static struct debug_obj_descr *descr_test __read_mostly; +static const struct debug_obj_descr *descr_test __read_mostly; +static struct kmem_cache *obj_cache __read_mostly; /* * Track numbers of kmem_cache_alloc()/free() calls done. @@ -71,7 +101,7 @@ static int debug_objects_freed; static void free_obj_work(struct work_struct *work); -static DECLARE_WORK(debug_obj_work, free_obj_work); +static DECLARE_DELAYED_WORK(debug_obj_work, free_obj_work); static int __init enable_object_debug(char *str) { @@ -99,29 +129,33 @@ static void fill_pool(void) { - gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN; - struct debug_obj *new, *obj; + gfp_t gfp = __GFP_HIGH | __GFP_NOWARN; + struct debug_obj *obj; unsigned long flags; - if (likely(obj_pool_free >= debug_objects_pool_min_level)) + if (likely(READ_ONCE(obj_pool_free) >= debug_objects_pool_min_level)) return; /* * Reuse objs from the global free list; they will be reinitialized * when allocating. + * + * Both obj_nr_tofree and obj_pool_free are checked locklessly; the + * READ_ONCE()s pair with the WRITE_ONCE()s in pool_lock critical + * sections. */ - while (obj_nr_tofree && (obj_pool_free < obj_pool_min_free)) { + while (READ_ONCE(obj_nr_tofree) && (READ_ONCE(obj_pool_free) < obj_pool_min_free)) { raw_spin_lock_irqsave(&pool_lock, flags); /* * Recheck with the lock held as the worker thread might have * won the race and freed the global free list already. */ - if (obj_nr_tofree) { + while (obj_nr_tofree && (obj_pool_free < obj_pool_min_free)) { obj = hlist_entry(obj_to_free.first, typeof(*obj), node); hlist_del(&obj->node); - obj_nr_tofree--; + WRITE_ONCE(obj_nr_tofree, obj_nr_tofree - 1); hlist_add_head(&obj->node, &obj_pool); - obj_pool_free++; + WRITE_ONCE(obj_pool_free, obj_pool_free + 1); } raw_spin_unlock_irqrestore(&pool_lock, flags); } @@ -129,16 +163,24 @@ if (unlikely(!obj_cache)) return; - while (obj_pool_free < debug_objects_pool_min_level) { + while (READ_ONCE(obj_pool_free) < debug_objects_pool_min_level) { + struct debug_obj *new[ODEBUG_BATCH_SIZE]; + int cnt; - new = kmem_cache_zalloc(obj_cache, gfp); - if (!new) + for (cnt = 0; cnt < ODEBUG_BATCH_SIZE; cnt++) { + new[cnt] = kmem_cache_zalloc(obj_cache, gfp); + if (!new[cnt]) + break; + } + if (!cnt) return; raw_spin_lock_irqsave(&pool_lock, flags); - hlist_add_head(&new->node, &obj_pool); - debug_objects_allocated++; - obj_pool_free++; + while (cnt) { + hlist_add_head(&new[--cnt]->node, &obj_pool); + debug_objects_allocated++; + WRITE_ONCE(obj_pool_free, obj_pool_free + 1); + } raw_spin_unlock_irqrestore(&pool_lock, flags); } } @@ -163,36 +205,77 @@ } /* - * Allocate a new object. If the pool is empty, switch off the debugger. - * Must be called with interrupts disabled. + * Allocate a new object from the hlist */ -static struct debug_obj * -alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) +static struct debug_obj *__alloc_object(struct hlist_head *list) { struct debug_obj *obj = NULL; - raw_spin_lock(&pool_lock); - if (obj_pool.first) { - obj = hlist_entry(obj_pool.first, typeof(*obj), node); - - obj->object = addr; - obj->descr = descr; - obj->state = ODEBUG_STATE_NONE; - obj->astate = 0; + if (list->first) { + obj = hlist_entry(list->first, typeof(*obj), node); hlist_del(&obj->node); + } - hlist_add_head(&obj->node, &b->list); + return obj; +} +static struct debug_obj * +alloc_object(void *addr, struct debug_bucket *b, const struct debug_obj_descr *descr) +{ + struct debug_percpu_free *percpu_pool = this_cpu_ptr(&percpu_obj_pool); + struct debug_obj *obj; + + if (likely(obj_cache)) { + obj = __alloc_object(&percpu_pool->free_objs); + if (obj) { + percpu_pool->obj_free--; + goto init_obj; + } + } + + raw_spin_lock(&pool_lock); + obj = __alloc_object(&obj_pool); + if (obj) { obj_pool_used++; + WRITE_ONCE(obj_pool_free, obj_pool_free - 1); + + /* + * Looking ahead, allocate one batch of debug objects and + * put them into the percpu free pool. + */ + if (likely(obj_cache)) { + int i; + + for (i = 0; i < ODEBUG_BATCH_SIZE; i++) { + struct debug_obj *obj2; + + obj2 = __alloc_object(&obj_pool); + if (!obj2) + break; + hlist_add_head(&obj2->node, + &percpu_pool->free_objs); + percpu_pool->obj_free++; + obj_pool_used++; + WRITE_ONCE(obj_pool_free, obj_pool_free - 1); + } + } + if (obj_pool_used > obj_pool_max_used) obj_pool_max_used = obj_pool_used; - obj_pool_free--; if (obj_pool_free < obj_pool_min_free) obj_pool_min_free = obj_pool_free; } raw_spin_unlock(&pool_lock); +init_obj: + if (obj) { + obj->object = addr; + obj->descr = descr; + obj->state = ODEBUG_STATE_NONE; + obj->astate = 0; + hlist_add_head(&obj->node, &b->list); + } return obj; } @@ -209,22 +292,31 @@ unsigned long flags; HLIST_HEAD(tofree); + WRITE_ONCE(obj_freeing, false); if (!raw_spin_trylock_irqsave(&pool_lock, flags)) return; + + if (obj_pool_free >= debug_objects_pool_size) + goto free_objs; /* * The objs on the pool list might be allocated before the work is * run, so recheck if pool list it full or not, if not fill pool - * list from the global free list + * list from the global free list. As it is likely that a workload + * may be gearing up to use more and more objects, don't free any + * of them until the next round. */ while (obj_nr_tofree && obj_pool_free < debug_objects_pool_size) { obj = hlist_entry(obj_to_free.first, typeof(*obj), node); hlist_del(&obj->node); hlist_add_head(&obj->node, &obj_pool); - obj_pool_free++; - obj_nr_tofree--; + WRITE_ONCE(obj_pool_free, obj_pool_free + 1); + WRITE_ONCE(obj_nr_tofree, obj_nr_tofree - 1); } + raw_spin_unlock_irqrestore(&pool_lock, flags); + return; +free_objs: /* * Pool list is already full and there are still objs on the free * list. Move remaining free objs to a temporary list to free the @@ -233,7 +325,7 @@ if (obj_nr_tofree) { hlist_move_list(&obj_to_free, &tofree); debug_objects_freed += obj_nr_tofree; - obj_nr_tofree = 0; + WRITE_ONCE(obj_nr_tofree, 0); } raw_spin_unlock_irqrestore(&pool_lock, flags); @@ -243,24 +335,86 @@ } } -static bool __free_object(struct debug_obj *obj) +static void __free_object(struct debug_obj *obj) { + struct debug_obj *objs[ODEBUG_BATCH_SIZE]; + struct debug_percpu_free *percpu_pool; + int lookahead_count = 0; unsigned long flags; bool work; - raw_spin_lock_irqsave(&pool_lock, flags); - work = (obj_pool_free > debug_objects_pool_size) && obj_cache; + local_irq_save(flags); + if (!obj_cache) + goto free_to_obj_pool; + + /* + * Try to free it into the percpu pool first. + */ + percpu_pool = this_cpu_ptr(&percpu_obj_pool); + if (percpu_pool->obj_free < ODEBUG_POOL_PERCPU_SIZE) { + hlist_add_head(&obj->node, &percpu_pool->free_objs); + percpu_pool->obj_free++; + local_irq_restore(flags); + return; + } + + /* + * As the percpu pool is full, look ahead and pull out a batch + * of objects from the percpu pool and free them as well. + */ + for (; lookahead_count < ODEBUG_BATCH_SIZE; lookahead_count++) { + objs[lookahead_count] = __alloc_object(&percpu_pool->free_objs); + if (!objs[lookahead_count]) + break; + percpu_pool->obj_free--; + } + +free_to_obj_pool: + raw_spin_lock(&pool_lock); + work = (obj_pool_free > debug_objects_pool_size) && obj_cache && + (obj_nr_tofree < ODEBUG_FREE_WORK_MAX); obj_pool_used--; if (work) { - obj_nr_tofree++; + WRITE_ONCE(obj_nr_tofree, obj_nr_tofree + 1); hlist_add_head(&obj->node, &obj_to_free); + if (lookahead_count) { + WRITE_ONCE(obj_nr_tofree, obj_nr_tofree + lookahead_count); + obj_pool_used -= lookahead_count; + while (lookahead_count) { + hlist_add_head(&objs[--lookahead_count]->node, + &obj_to_free); + } + } + + if ((obj_pool_free > debug_objects_pool_size) && + (obj_nr_tofree < ODEBUG_FREE_WORK_MAX)) { + int i; + + /* + * Free one more batch of objects from obj_pool. + */ + for (i = 0; i < ODEBUG_BATCH_SIZE; i++) { + obj = __alloc_object(&obj_pool); + hlist_add_head(&obj->node, &obj_to_free); + WRITE_ONCE(obj_pool_free, obj_pool_free - 1); + WRITE_ONCE(obj_nr_tofree, obj_nr_tofree + 1); + } + } } else { - obj_pool_free++; + WRITE_ONCE(obj_pool_free, obj_pool_free + 1); hlist_add_head(&obj->node, &obj_pool); + if (lookahead_count) { + WRITE_ONCE(obj_pool_free, obj_pool_free + lookahead_count); + obj_pool_used -= lookahead_count; + while (lookahead_count) { + hlist_add_head(&objs[--lookahead_count]->node, + &obj_pool); + } + } } - raw_spin_unlock_irqrestore(&pool_lock, flags); - return work; + raw_spin_unlock(&pool_lock); + local_irq_restore(flags); } /* @@ -269,9 +423,38 @@ */ static void free_object(struct debug_obj *obj) { - if (__free_object(obj)) - schedule_work(&debug_obj_work); + __free_object(obj); + if (!READ_ONCE(obj_freeing) && READ_ONCE(obj_nr_tofree)) { + WRITE_ONCE(obj_freeing, true); + schedule_delayed_work(&debug_obj_work, ODEBUG_FREE_WORK_DELAY); + } } + +#ifdef CONFIG_HOTPLUG_CPU +static int object_cpu_offline(unsigned int cpu) +{ + struct debug_percpu_free *percpu_pool; + struct hlist_node *tmp; + struct debug_obj *obj; + unsigned long flags; + + /* Remote access is safe as the CPU is dead already */ + percpu_pool = per_cpu_ptr(&percpu_obj_pool, cpu); + hlist_for_each_entry_safe(obj, tmp, &percpu_pool->free_objs, node) { + hlist_del(&obj->node); + kmem_cache_free(obj_cache, obj); + } + + raw_spin_lock_irqsave(&pool_lock, flags); + obj_pool_used -= percpu_pool->obj_free; + debug_objects_freed += percpu_pool->obj_free; + raw_spin_unlock_irqrestore(&pool_lock, flags); + + percpu_pool->obj_free = 0; + + return 0; +} +#endif /* * We run out of memory. That means we probably have tons of objects @@ -315,8 +498,17 @@ static void debug_print_object(struct debug_obj *obj, char *msg) { - struct debug_obj_descr *descr = obj->descr; + const struct debug_obj_descr *descr = obj->descr; static int limit; + + /* + * Don't report if lookup_object_or_alloc() by the current thread + * failed because lookup_object_or_alloc()/debug_objects_oom() by a + * concurrent thread turned off debug_objects_enabled and cleared + * the hash buckets. + */ + if (!debug_objects_enabled) + return; if (limit < 5 && descr != descr_test) { void *hint = descr->debug_hint ? @@ -368,33 +560,74 @@ WARN_ON(1); } +static struct debug_obj *lookup_object_or_alloc(void *addr, struct debug_bucket *b, + const struct debug_obj_descr *descr, + bool onstack, bool alloc_ifstatic) +{ + struct debug_obj *obj = lookup_object(addr, b); + enum debug_obj_state state = ODEBUG_STATE_NONE; + + if (likely(obj)) + return obj; + + /* + * debug_object_init() unconditionally allocates untracked + * objects. It does not matter whether it is a static object or + * not. + * + * debug_object_assert_init() and debug_object_activate() allow + * allocation only if the descriptor callback confirms that the + * object is static and considered initialized. For non-static + * objects the allocation needs to be done from the fixup callback. + */ + if (unlikely(alloc_ifstatic)) { + if (!descr->is_static_object || !descr->is_static_object(addr)) + return ERR_PTR(-ENOENT); + /* Statically allocated objects are considered initialized */ + state = ODEBUG_STATE_INIT; + } + + obj = alloc_object(addr, b, descr); + if (likely(obj)) { + obj->state = state; + debug_object_is_on_stack(addr, onstack); + return obj; + } + + /* Out of memory. Do the cleanup outside of the locked region */ + debug_objects_enabled = 0; + return NULL; +} + +static void debug_objects_fill_pool(void) +{ + /* + * On RT enabled kernels the pool refill must happen in preemptible + * context: + */ + if (!IS_ENABLED(CONFIG_PREEMPT_RT) || preemptible()) + fill_pool(); +} + static void -__debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack) +__debug_object_init(void *addr, const struct debug_obj_descr *descr, int onstack) { enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; -#ifdef CONFIG_PREEMPT_RT_FULL - if (preempt_count() == 0 && !irqs_disabled()) -#endif - fill_pool(); + debug_objects_fill_pool(); db = get_bucket((unsigned long) addr); raw_spin_lock_irqsave(&db->lock, flags); - obj = lookup_object(addr, db); - if (!obj) { - obj = alloc_object(addr, db, descr); - if (!obj) { - debug_objects_enabled = 0; - raw_spin_unlock_irqrestore(&db->lock, flags); - debug_objects_oom(); - return; - } - debug_object_is_on_stack(addr, onstack); + obj = lookup_object_or_alloc(addr, db, descr, onstack, false); + if (unlikely(!obj)) { + raw_spin_unlock_irqrestore(&db->lock, flags); + debug_objects_oom(); + return; } switch (obj->state) { @@ -405,15 +638,16 @@ break; case ODEBUG_STATE_ACTIVE: - debug_print_object(obj, "init"); state = obj->state; raw_spin_unlock_irqrestore(&db->lock, flags); + debug_print_object(obj, "init"); debug_object_fixup(descr->fixup_init, addr, state); return; case ODEBUG_STATE_DESTROYED: + raw_spin_unlock_irqrestore(&db->lock, flags); debug_print_object(obj, "init"); - break; + return; default: break; } @@ -426,7 +660,7 @@ * @addr: address of the object * @descr: pointer to an object specific debug description structure */ -void debug_object_init(void *addr, struct debug_obj_descr *descr) +void debug_object_init(void *addr, const struct debug_obj_descr *descr) { if (!debug_objects_enabled) return; @@ -441,7 +675,7 @@ * @addr: address of the object * @descr: pointer to an object specific debug description structure */ -void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr) +void debug_object_init_on_stack(void *addr, const struct debug_obj_descr *descr) { if (!debug_objects_enabled) return; @@ -456,26 +690,28 @@ * @descr: pointer to an object specific debug description structure * Returns 0 for success, -EINVAL for check failed. */ -int debug_object_activate(void *addr, struct debug_obj_descr *descr) +int debug_object_activate(void *addr, const struct debug_obj_descr *descr) { + struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; int ret; - struct debug_obj o = { .object = addr, - .state = ODEBUG_STATE_NOTAVAILABLE, - .descr = descr }; if (!debug_objects_enabled) return 0; + + debug_objects_fill_pool(); db = get_bucket((unsigned long) addr); raw_spin_lock_irqsave(&db->lock, flags); - obj = lookup_object(addr, db); - if (obj) { + obj = lookup_object_or_alloc(addr, db, descr, false, true); + if (likely(!IS_ERR_OR_NULL(obj))) { + bool print_object = false; + switch (obj->state) { case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: @@ -484,14 +720,14 @@ break; case ODEBUG_STATE_ACTIVE: - debug_print_object(obj, "activate"); state = obj->state; raw_spin_unlock_irqrestore(&db->lock, flags); + debug_print_object(obj, "activate"); ret = debug_object_fixup(descr->fixup_activate, addr, state); return ret ? 0 : -EINVAL; case ODEBUG_STATE_DESTROYED: - debug_print_object(obj, "activate"); + print_object = true; ret = -EINVAL; break; default: @@ -499,28 +735,23 @@ break; } raw_spin_unlock_irqrestore(&db->lock, flags); + if (print_object) + debug_print_object(obj, "activate"); return ret; } raw_spin_unlock_irqrestore(&db->lock, flags); - /* - * We are here when a static object is activated. We - * let the type specific code confirm whether this is - * true or not. if true, we just make sure that the - * static object is tracked in the object tracker. If - * not, this must be a bug, so we try to fix it up. - */ - if (descr->is_static_object && descr->is_static_object(addr)) { - /* track this static object */ - debug_object_init(addr, descr); - debug_object_activate(addr, descr); - } else { - debug_print_object(&o, "activate"); - ret = debug_object_fixup(descr->fixup_activate, addr, - ODEBUG_STATE_NOTAVAILABLE); - return ret ? 0 : -EINVAL; + + /* If NULL the allocation has hit OOM */ + if (!obj) { + debug_objects_oom(); + return 0; } - return 0; + + /* Object is neither static nor tracked. It's not initialized */ + debug_print_object(&o, "activate"); + ret = debug_object_fixup(descr->fixup_activate, addr, ODEBUG_STATE_NOTAVAILABLE); + return ret ? 0 : -EINVAL; } EXPORT_SYMBOL_GPL(debug_object_activate); @@ -529,11 +760,12 @@ * @addr: address of the object * @descr: pointer to an object specific debug description structure */ -void debug_object_deactivate(void *addr, struct debug_obj_descr *descr) +void debug_object_deactivate(void *addr, const struct debug_obj_descr *descr) { struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; + bool print_object = false; if (!debug_objects_enabled) return; @@ -551,24 +783,27 @@ if (!obj->astate) obj->state = ODEBUG_STATE_INACTIVE; else - debug_print_object(obj, "deactivate"); + print_object = true; break; case ODEBUG_STATE_DESTROYED: - debug_print_object(obj, "deactivate"); + print_object = true; break; default: break; } - } else { + } + + raw_spin_unlock_irqrestore(&db->lock, flags); + if (!obj) { struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; debug_print_object(&o, "deactivate"); + } else if (print_object) { + debug_print_object(obj, "deactivate"); } - - raw_spin_unlock_irqrestore(&db->lock, flags); } EXPORT_SYMBOL_GPL(debug_object_deactivate); @@ -577,12 +812,13 @@ * @addr: address of the object * @descr: pointer to an object specific debug description structure */ -void debug_object_destroy(void *addr, struct debug_obj_descr *descr) +void debug_object_destroy(void *addr, const struct debug_obj_descr *descr) { enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; + bool print_object = false; if (!debug_objects_enabled) return; @@ -602,20 +838,22 @@ obj->state = ODEBUG_STATE_DESTROYED; break; case ODEBUG_STATE_ACTIVE: - debug_print_object(obj, "destroy"); state = obj->state; raw_spin_unlock_irqrestore(&db->lock, flags); + debug_print_object(obj, "destroy"); debug_object_fixup(descr->fixup_destroy, addr, state); return; case ODEBUG_STATE_DESTROYED: - debug_print_object(obj, "destroy"); + print_object = true; break; default: break; } out_unlock: raw_spin_unlock_irqrestore(&db->lock, flags); + if (print_object) + debug_print_object(obj, "destroy"); } EXPORT_SYMBOL_GPL(debug_object_destroy); @@ -624,7 +862,7 @@ * @addr: address of the object * @descr: pointer to an object specific debug description structure */ -void debug_object_free(void *addr, struct debug_obj_descr *descr) +void debug_object_free(void *addr, const struct debug_obj_descr *descr) { enum debug_obj_state state; struct debug_bucket *db; @@ -644,9 +882,9 @@ switch (obj->state) { case ODEBUG_STATE_ACTIVE: - debug_print_object(obj, "free"); state = obj->state; raw_spin_unlock_irqrestore(&db->lock, flags); + debug_print_object(obj, "free"); debug_object_fixup(descr->fixup_free, addr, state); return; default: @@ -665,8 +903,9 @@ * @addr: address of the object * @descr: pointer to an object specific debug description structure */ -void debug_object_assert_init(void *addr, struct debug_obj_descr *descr) +void debug_object_assert_init(void *addr, const struct debug_obj_descr *descr) { + struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; @@ -674,34 +913,25 @@ if (!debug_objects_enabled) return; + debug_objects_fill_pool(); + db = get_bucket((unsigned long) addr); raw_spin_lock_irqsave(&db->lock, flags); + obj = lookup_object_or_alloc(addr, db, descr, false, true); + raw_spin_unlock_irqrestore(&db->lock, flags); + if (likely(!IS_ERR_OR_NULL(obj))) + return; - obj = lookup_object(addr, db); + /* If NULL the allocation has hit OOM */ if (!obj) { - struct debug_obj o = { .object = addr, - .state = ODEBUG_STATE_NOTAVAILABLE, - .descr = descr }; - - raw_spin_unlock_irqrestore(&db->lock, flags); - /* - * Maybe the object is static, and we let the type specific - * code confirm. Track this static object if true, else invoke - * fixup. - */ - if (descr->is_static_object && descr->is_static_object(addr)) { - /* Track this static object */ - debug_object_init(addr, descr); - } else { - debug_print_object(&o, "assert_init"); - debug_object_fixup(descr->fixup_assert_init, addr, - ODEBUG_STATE_NOTAVAILABLE); - } + debug_objects_oom(); return; } - raw_spin_unlock_irqrestore(&db->lock, flags); + /* Object is neither tracked nor static. It's not initialized. */ + debug_print_object(&o, "assert_init"); + debug_object_fixup(descr->fixup_assert_init, addr, ODEBUG_STATE_NOTAVAILABLE); } EXPORT_SYMBOL_GPL(debug_object_assert_init); @@ -713,12 +943,13 @@ * @next: state to move to if expected state is found */ void -debug_object_active_state(void *addr, struct debug_obj_descr *descr, +debug_object_active_state(void *addr, const struct debug_obj_descr *descr, unsigned int expect, unsigned int next) { struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; + bool print_object = false; if (!debug_objects_enabled) return; @@ -734,22 +965,25 @@ if (obj->astate == expect) obj->astate = next; else - debug_print_object(obj, "active_state"); + print_object = true; break; default: - debug_print_object(obj, "active_state"); + print_object = true; break; } - } else { + } + + raw_spin_unlock_irqrestore(&db->lock, flags); + if (!obj) { struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; debug_print_object(&o, "active_state"); + } else if (print_object) { + debug_print_object(obj, "active_state"); } - - raw_spin_unlock_irqrestore(&db->lock, flags); } EXPORT_SYMBOL_GPL(debug_object_active_state); @@ -757,13 +991,12 @@ static void __debug_check_no_obj_freed(const void *address, unsigned long size) { unsigned long flags, oaddr, saddr, eaddr, paddr, chunks; - struct debug_obj_descr *descr; + const struct debug_obj_descr *descr; enum debug_obj_state state; struct debug_bucket *db; struct hlist_node *tmp; struct debug_obj *obj; int cnt, objs_checked = 0; - bool work = false; saddr = (unsigned long) address; eaddr = saddr + size; @@ -785,16 +1018,16 @@ switch (obj->state) { case ODEBUG_STATE_ACTIVE: - debug_print_object(obj, "free"); descr = obj->descr; state = obj->state; raw_spin_unlock_irqrestore(&db->lock, flags); + debug_print_object(obj, "free"); debug_object_fixup(descr->fixup_free, (void *) oaddr, state); goto repeat; default: hlist_del(&obj->node); - work |= __free_object(obj); + __free_object(obj); break; } } @@ -810,8 +1043,10 @@ debug_objects_maxchecked = objs_checked; /* Schedule work to actually kmem_cache_free() objects */ - if (work) - schedule_work(&debug_obj_work); + if (!READ_ONCE(obj_freeing) && READ_ONCE(obj_nr_tofree)) { + WRITE_ONCE(obj_freeing, true); + schedule_delayed_work(&debug_obj_work, ODEBUG_FREE_WORK_DELAY); + } } void debug_check_no_obj_freed(const void *address, unsigned long size) @@ -825,54 +1060,39 @@ static int debug_stats_show(struct seq_file *m, void *v) { + int cpu, obj_percpu_free = 0; + + for_each_possible_cpu(cpu) + obj_percpu_free += per_cpu(percpu_obj_pool.obj_free, cpu); + seq_printf(m, "max_chain :%d\n", debug_objects_maxchain); seq_printf(m, "max_checked :%d\n", debug_objects_maxchecked); seq_printf(m, "warnings :%d\n", debug_objects_warnings); seq_printf(m, "fixups :%d\n", debug_objects_fixups); - seq_printf(m, "pool_free :%d\n", obj_pool_free); + seq_printf(m, "pool_free :%d\n", READ_ONCE(obj_pool_free) + obj_percpu_free); + seq_printf(m, "pool_pcp_free :%d\n", obj_percpu_free); seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free); - seq_printf(m, "pool_used :%d\n", obj_pool_used); + seq_printf(m, "pool_used :%d\n", obj_pool_used - obj_percpu_free); seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used); - seq_printf(m, "on_free_list :%d\n", obj_nr_tofree); + seq_printf(m, "on_free_list :%d\n", READ_ONCE(obj_nr_tofree)); seq_printf(m, "objs_allocated:%d\n", debug_objects_allocated); seq_printf(m, "objs_freed :%d\n", debug_objects_freed); return 0; } - -static int debug_stats_open(struct inode *inode, struct file *filp) -{ - return single_open(filp, debug_stats_show, NULL); -} - -static const struct file_operations debug_stats_fops = { - .open = debug_stats_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; +DEFINE_SHOW_ATTRIBUTE(debug_stats); static int __init debug_objects_init_debugfs(void) { - struct dentry *dbgdir, *dbgstats; + struct dentry *dbgdir; if (!debug_objects_enabled) return 0; dbgdir = debugfs_create_dir("debug_objects", NULL); - if (!dbgdir) - return -ENOMEM; - dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL, - &debug_stats_fops); - if (!dbgstats) - goto err; + debugfs_create_file("stats", 0444, dbgdir, NULL, &debug_stats_fops); return 0; - -err: - debugfs_remove(dbgdir); - - return -ENOMEM; } __initcall(debug_objects_init_debugfs); @@ -889,7 +1109,7 @@ unsigned long dummy2[3]; }; -static __initdata struct debug_obj_descr descr_type_test; +static __initconst const struct debug_obj_descr descr_type_test; static bool __init is_static_object(void *addr) { @@ -1014,7 +1234,7 @@ return res; } -static __initdata struct debug_obj_descr descr_type_test = { +static __initconst const struct debug_obj_descr descr_type_test = { .name = "selftest", .is_static_object = is_static_object, .fixup_init = fixup_init, @@ -1133,12 +1353,13 @@ hlist_add_head(&obj->node, &objects); } + debug_objects_allocated += i; + /* - * When debug_objects_mem_init() is called we know that only - * one CPU is up, so disabling interrupts is enough - * protection. This avoids the lockdep hell of lock ordering. + * debug_objects_mem_init() is now called early that only one CPU is up + * and interrupts have been disabled, so it is safe to replace the + * active object references. */ - local_irq_disable(); /* Remove the statically allocated objects from the pool */ hlist_for_each_entry_safe(obj, tmp, &obj_pool, node) @@ -1159,7 +1380,6 @@ cnt++; } } - local_irq_enable(); pr_debug("%d of %d active objects replaced\n", cnt, obj_pool_used); @@ -1180,8 +1400,19 @@ */ void __init debug_objects_mem_init(void) { + int cpu, extras; + if (!debug_objects_enabled) return; + + /* + * Initialize the percpu object pools + * + * Initialization is not strictly necessary, but was done for + * completeness. + */ + for_each_possible_cpu(cpu) + INIT_HLIST_HEAD(&per_cpu(percpu_obj_pool.free_objs, cpu)); obj_cache = kmem_cache_create("debug_objects_cache", sizeof (struct debug_obj), 0, @@ -1192,13 +1423,20 @@ debug_objects_enabled = 0; kmem_cache_destroy(obj_cache); pr_warn("out of memory.\n"); + return; } else debug_objects_selftest(); + +#ifdef CONFIG_HOTPLUG_CPU + cpuhp_setup_state_nocalls(CPUHP_DEBUG_OBJ_DEAD, "object:offline", NULL, + object_cpu_offline); +#endif /* * Increase the thresholds for allocating and freeing objects * according to the number of possible CPUs available in the system. */ - debug_objects_pool_size += num_possible_cpus() * 32; - debug_objects_pool_min_level += num_possible_cpus() * 4; + extras = num_possible_cpus() * ODEBUG_BATCH_SIZE; + debug_objects_pool_size += extras; + debug_objects_pool_min_level += extras; } -- Gitblit v1.6.2