mm/page_reporting.h

   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 */