1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _MM_PAGE_REPORTING_H
3#define _MM_PAGE_REPORTING_H
4
5#include <linux/mmzone.h>
6#include <linux/pageblock-flags.h>
7#include <linux/page-isolation.h>
8#include <linux/jump_label.h>
9#include <linux/slab.h>
10#include <linux/pgtable.h>
11#include <linux/scatterlist.h>
12
13#ifdef CONFIG_PAGE_REPORTING
14DECLARE_STATIC_KEY_FALSE(page_reporting_enabled);
15extern unsigned int page_reporting_order;
16void __page_reporting_notify(void);
17
18static inline bool page_reported(struct page *page)
19{
20 return static_branch_unlikely(&page_reporting_enabled) &&
21 PageReported(page);
22}
23
24/**
25 * page_reporting_notify_free - Free page notification to start page processing
26 *
27 * This function is meant to act as a screener for __page_reporting_notify
28 * which will determine if a give zone has crossed over the high-water mark
29 * that will justify us beginning page treatment. If we have crossed that
30 * threshold then it will start the process of pulling some pages and
31 * placing them in the batch list for treatment.
32 */
33static inline void page_reporting_notify_free(unsigned int order)
34{
35 /* Called from hot path in __free_one_page() */
36 if (!static_branch_unlikely(&page_reporting_enabled))
37 return;
38
39 /* Determine if we have crossed reporting threshold */
40 if (order < page_reporting_order)
41 return;
42
43 /* This will add a few cycles, but should be called infrequently */
44 __page_reporting_notify();
45}
46#else /* CONFIG_PAGE_REPORTING */
47#define page_reported(_page) false
48
49static inline void page_reporting_notify_free(unsigned int order)
50{
51}
52#endif /* CONFIG_PAGE_REPORTING */
53#endif /*_MM_PAGE_REPORTING_H */
54

source code of linux/mm/page_reporting.h