xref: /openbmc/linux/mm/page_reporting.h (revision 7a010c3c)
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
14 DECLARE_STATIC_KEY_FALSE(page_reporting_enabled);
15 extern unsigned int page_reporting_order;
16 void __page_reporting_notify(void);
17 
18 static 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  */
33 static 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 
49 static inline void page_reporting_notify_free(unsigned int order)
50 {
51 }
52 #endif /* CONFIG_PAGE_REPORTING */
53 #endif /*_MM_PAGE_REPORTING_H */
54