[PATCH 6.1 0125/1146] lib/debugobjects: fix stat count and optimize debug_objects_mem_init

Greg Kroah-Hartman
2022-12-28T15:17:45Z

From: wuchi <wuchi.zero@gmail.com>

[ Upstream commit eabb7f1ace53e127309407b2b5e74e8199e85270 ]

1. Var debug_objects_allocated tracks valid kmem_cache_alloc calls, so
track it in debug_objects_replace_static_objects. Do similar things in
object_cpu_offline.

2. In debug_objects_mem_init, there is no need to call function
cpuhp_setup_state_nocalls when debug_objects_enabled = 0 (out of
memory).

Link: https://lkml.kernel.org/r/20220611130634.99741-1-wuchi.zero@gmail.com
Fixes: 634d61f45d6f ("debugobjects: Percpu pool lookahead freeing/allocation")
Fixes: c4b73aabd098 ("debugobjects: Track number of kmem_cache_alloc/kmem_cache_free done")
Signed-off-by: wuchi <wuchi.zero@gmail.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
lib/debugobjects.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 337d797a7141..6f8e5dd1dcd0 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -437,6 +437,7 @@ 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);
@@ -444,6 +445,12 @@ static int object_cpu_offline(unsigned int cpu)
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;
@@ -1318,6 +1325,8 @@ static int __init debug_objects_replace_static_objects(void)
hlist_add_head(&obj->node, &objects);
}

+ debug_objects_allocated += i;
+
/*
* 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
@@ -1386,6 +1395,7 @@ void __init debug_objects_mem_init(void)
debug_objects_enabled = 0;
kmem_cache_destroy(obj_cache);
pr_warn("out of memory.\n");
+ return;
} else
debug_objects_selftest();

--
2.35.1