kernel/watchdog: split up config options

[mirror_ubuntu-bionic-kernel.git] / include / linux / mmzone.h

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 976a1202bec113a47519b106ba0926787afe2d4a..fc14b8b3f6ce8a7cdd2a70ef89906c22d52f3b55 100644 (file)
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -125,8 +125,6 @@ enum zone_stat_item {
        NR_ZONE_UNEVICTABLE,
        NR_ZONE_WRITE_PENDING,  /* Count of dirty, writeback and unstable pages */
        NR_MLOCK,               /* mlock()ed pages found and moved off LRU */
-       NR_SLAB_RECLAIMABLE,
-       NR_SLAB_UNRECLAIMABLE,
        NR_PAGETABLE,           /* used for pagetables */
        NR_KERNEL_STACK_KB,     /* measured in KiB */
        /* Second 128 byte cacheline */
@@ -152,6 +150,8 @@ enum node_stat_item {
        NR_INACTIVE_FILE,       /*  "     "     "   "       "         */
        NR_ACTIVE_FILE,         /*  "     "     "   "       "         */
        NR_UNEVICTABLE,         /*  "     "     "   "       "         */
+       NR_SLAB_RECLAIMABLE,
+       NR_SLAB_UNRECLAIMABLE,
        NR_ISOLATED_ANON,       /* Temporary isolated pages from anon lru */
        NR_ISOLATED_FILE,       /* Temporary isolated pages from file lru */
        WORKINGSET_REFAULT,
@@ -532,6 +532,22 @@ static inline bool zone_is_empty(struct zone *zone)
        return zone->spanned_pages == 0;
 }
 
+/*
+ * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty
+ * intersection with the given zone
+ */
+static inline bool zone_intersects(struct zone *zone,
+               unsigned long start_pfn, unsigned long nr_pages)
+{
+       if (zone_is_empty(zone))
+               return false;
+       if (start_pfn >= zone_end_pfn(zone) ||
+           start_pfn + nr_pages <= zone->zone_start_pfn)
+               return false;
+
+       return true;
+}
+
 /*
  * The "priority" of VM scanning is how much of the queues we will scan in one
  * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
@@ -587,12 +603,9 @@ extern struct page *mem_map;
 #endif
 
 /*
- * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
- * (mostly NUMA machines?) to denote a higher-level memory zone than the
- * zone denotes.
- *
  * On NUMA machines, each NUMA node would have a pg_data_t to describe
- * it's memory layout.
+ * it's memory layout. On UMA machines there is a single pglist_data which
+ * describes the whole memory.
  *
  * Memory statistics and page replacement data structures are maintained on a
  * per-zone basis.
@@ -1042,6 +1055,7 @@ static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
        !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
 static inline unsigned long early_pfn_to_nid(unsigned long pfn)
 {
+       BUILD_BUG_ON(IS_ENABLED(CONFIG_NUMA));
        return 0;
 }
 #endif
@@ -1144,9 +1158,10 @@ extern unsigned long usemap_size(void);
  */
 #define        SECTION_MARKED_PRESENT  (1UL<<0)
 #define SECTION_HAS_MEM_MAP    (1UL<<1)
-#define SECTION_MAP_LAST_BIT   (1UL<<2)
+#define SECTION_IS_ONLINE      (1UL<<2)
+#define SECTION_MAP_LAST_BIT   (1UL<<3)
 #define SECTION_MAP_MASK       (~(SECTION_MAP_LAST_BIT-1))
-#define SECTION_NID_SHIFT      2
+#define SECTION_NID_SHIFT      3
 
 static inline struct page *__section_mem_map_addr(struct mem_section *section)
 {
@@ -1175,6 +1190,23 @@ static inline int valid_section_nr(unsigned long nr)
        return valid_section(__nr_to_section(nr));
 }
 
+static inline int online_section(struct mem_section *section)
+{
+       return (section && (section->section_mem_map & SECTION_IS_ONLINE));
+}
+
+static inline int online_section_nr(unsigned long nr)
+{
+       return online_section(__nr_to_section(nr));
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn);
+#ifdef CONFIG_MEMORY_HOTREMOVE
+void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn);
+#endif
+#endif
+
 static inline struct mem_section *__pfn_to_section(unsigned long pfn)
 {
        return __nr_to_section(pfn_to_section_nr(pfn));
@@ -1253,10 +1285,15 @@ unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
 /*
  * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
- * associated with it or not. In FLATMEM, it is expected that holes always
- * have valid memmap as long as there is valid PFNs either side of the hole.
- * In SPARSEMEM, it is assumed that a valid section has a memmap for the
- * entire section.
+ * associated with it or not. This means that a struct page exists for this
+ * pfn. The caller cannot assume the page is fully initialized in general.
+ * Hotplugable pages might not have been onlined yet. pfn_to_online_page()
+ * will ensure the struct page is fully online and initialized. Special pages
+ * (e.g. ZONE_DEVICE) are never onlined and should be treated accordingly.
+ *
+ * In FLATMEM, it is expected that holes always have valid memmap as long as
+ * there is valid PFNs either side of the hole. In SPARSEMEM, it is assumed
+ * that a valid section has a memmap for the entire section.
  *
  * However, an ARM, and maybe other embedded architectures in the future
  * free memmap backing holes to save memory on the assumption the memmap is