/* SPDX-License-Identifier: GPL-2.0 */
/*
 * page allocation tagging
 */
#ifndef _LINUX_PGALLOC_TAG_H
#define _LINUX_PGALLOC_TAG_H

#include <linux/alloc_tag.h>

#ifdef CONFIG_MEM_ALLOC_PROFILING

#include <linux/page_ext.h>

extern struct page_ext_operations page_alloc_tagging_ops;
extern struct page_ext *page_ext_get(struct page *page);
extern void page_ext_put(struct page_ext *page_ext);

static inline union codetag_ref *codetag_ref_from_page_ext(struct page_ext *page_ext)
{
	return (void *)page_ext + page_alloc_tagging_ops.offset;
}

static inline struct page_ext *page_ext_from_codetag_ref(union codetag_ref *ref)
{
	return (void *)ref - page_alloc_tagging_ops.offset;
}

/* Should be called only if mem_alloc_profiling_enabled() */
static inline union codetag_ref *get_page_tag_ref(struct page *page)
{
	if (page) {
		struct page_ext *page_ext = page_ext_get(page);

		if (page_ext)
			return codetag_ref_from_page_ext(page_ext);
	}
	return NULL;
}

static inline void put_page_tag_ref(union codetag_ref *ref)
{
	page_ext_put(page_ext_from_codetag_ref(ref));
}

static inline void pgalloc_tag_add(struct page *page, struct task_struct *task,
				   unsigned int nr)
{
	if (mem_alloc_profiling_enabled()) {
		union codetag_ref *ref = get_page_tag_ref(page);

		if (ref) {
			alloc_tag_add(ref, task->alloc_tag, PAGE_SIZE * nr);
			put_page_tag_ref(ref);
		}
	}
}

static inline void pgalloc_tag_sub(struct page *page, unsigned int nr)
{
	if (mem_alloc_profiling_enabled()) {
		union codetag_ref *ref = get_page_tag_ref(page);

		if (ref) {
			alloc_tag_sub(ref, PAGE_SIZE * nr);
			put_page_tag_ref(ref);
		}
	}
}

#else /* CONFIG_MEM_ALLOC_PROFILING */

static inline void pgalloc_tag_add(struct page *page, struct task_struct *task,
				   unsigned int nr) {}
static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {}

#endif /* CONFIG_MEM_ALLOC_PROFILING */

#endif /* _LINUX_PGALLOC_TAG_H */