Commit cc0c8bcf authored by Liu Shixin's avatar Liu Shixin
Browse files

mm: kmemleak: split __create_object into two functions 

mainline inclusion
from mainline-v6.7-rc1
commit 0edd7b58293340d26380d7510fd4fc08e5902511
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IBE0E0

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0edd7b58293340d26380d7510fd4fc08e5902511

--------------------------------

__create_object() consists of two part, the first part allocate a kmemleak
object and initialize it, the second part insert it into object tree.
This function need kmemleak_lock but actually only the second part need
lock.

Split it into two functions, the first function __alloc_object only
allocate a kmemleak object, and the second function __link_object() will
initialize the object and insert it into object tree, use the
kmemleak_lock to protect __link_object() only.

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20231018102952.3339837-5-liushixin2@huawei.com


Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Patrick Wang <patrick.wang.shcn@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
parent 1e25ad3b

mm/kmemleak.c

+40 −21
Original line number Diff line number Diff line
@@ -623,25 +623,15 @@ static noinline depot_stack_handle_t set_track_prepare(void) 
	return trace_handle;

}



/*

 * Create the metadata (struct kmemleak_object) corresponding to an allocated

 * memory block and add it to the object_list and object_tree_root (or

 * object_phys_tree_root).

 */

static void __create_object(unsigned long ptr, size_t size,

			    int min_count, gfp_t gfp, bool is_phys)

static struct kmemleak_object *__alloc_object(gfp_t gfp)

{

	unsigned long flags;

	struct kmemleak_object *object, *parent;

	struct rb_node **link, *rb_parent;

	unsigned long untagged_ptr;

	unsigned long untagged_objp;

	struct kmemleak_object *object;



	object = mem_pool_alloc(gfp);

	if (!object) {

		pr_warn("Cannot allocate a kmemleak_object structure\n");

		kmemleak_disable();

		return;

		return NULL;

	}



	INIT_LIST_HEAD(&object->object_list);
@@ -649,13 +639,8 @@ static void __create_object(unsigned long ptr, size_t size, 
	INIT_HLIST_HEAD(&object->area_list);

	raw_spin_lock_init(&object->lock);

	atomic_set(&object->use_count, 1);

	object->flags = OBJECT_ALLOCATED | (is_phys ? OBJECT_PHYS : 0);

	object->pointer = ptr;

	object->size = kfence_ksize((void *)ptr) ?: size;

	object->excess_ref = 0;

	object->min_count = min_count;

	object->count = 0;			/* white color initially */

	object->jiffies = jiffies;

	object->checksum = 0;

	object->del_state = 0;
@@ -680,7 +665,23 @@ static void __create_object(unsigned long ptr, size_t size, 
	/* kernel backtrace */

	object->trace_handle = set_track_prepare();



	raw_spin_lock_irqsave(&kmemleak_lock, flags);

	return object;

}



static void __link_object(struct kmemleak_object *object, unsigned long ptr,

			  size_t size, int min_count, bool is_phys)

{



	struct kmemleak_object *parent;

	struct rb_node **link, *rb_parent;

	unsigned long untagged_ptr;

	unsigned long untagged_objp;



	object->flags = OBJECT_ALLOCATED | (is_phys ? OBJECT_PHYS : 0);

	object->pointer = ptr;

	object->size = kfence_ksize((void *)ptr) ?: size;

	object->min_count = min_count;

	object->jiffies = jiffies;



	untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr);

	/*
@@ -711,14 +712,32 @@ static void __create_object(unsigned long ptr, size_t size, 
			 */

			dump_object_info(parent);

			kmem_cache_free(object_cache, object);

			goto out;

			return;

		}

	}

	rb_link_node(&object->rb_node, rb_parent, link);

	rb_insert_color(&object->rb_node, is_phys ? &object_phys_tree_root :

					  &object_tree_root);

	list_add_tail_rcu(&object->object_list, &object_list);

out:

}



/*

 * Create the metadata (struct kmemleak_object) corresponding to an allocated

 * memory block and add it to the object_list and object_tree_root (or

 * object_phys_tree_root).

 */

static void __create_object(unsigned long ptr, size_t size,

				int min_count, gfp_t gfp, bool is_phys)

{

	struct kmemleak_object *object;

	unsigned long flags;



	object = __alloc_object(gfp);

	if (!object)

		return;



	raw_spin_lock_irqsave(&kmemleak_lock, flags);

	__link_object(object, ptr, size, min_count, is_phys);

	raw_spin_unlock_irqrestore(&kmemleak_lock, flags);

}