zoneinfo

由于有次使用for_each_zone 的函数 无法使用

mm/bootmem.c#0027 这里定义吗 ？
0026 #ifndef CONFIG_NEED_MULTIPLE_NODES
0027 struct pglist_data __refdata contig_page_data = {
0028         .bdata = &bootmem_node_data[0]
0029 };
0030 EXPORT_SYMBOL(contig_page_data);

mm/bootmem.c#0027 ？

0026 #ifndef CONFIG_NEED_MULTIPLE_NODES
0027 struct pglist_data __refdata contig_page_data;
0028 EXPORT_SYMBOL(contig_page_data);
0029 #endif

直接有个结构体：
0860 extern struct pglist_data contig_page_data;


module 打印
　　　　　printk( "node_data = *%p* \n", &contig_page_data );
        printk( "contig_page_data.node_zones[0] = [%s] \n",
                contig_page_data.node_zones[0].name );
        printk( "contig_page_data.node_zones[1] = [%s] \n",
                contig_page_data.node_zones[1].name );
        printk( "contig_page_data.node_zones[2] = [%s] \n",
                contig_page_data.node_zones[2].name );
        if( contig_page_data.node_zones[3].name )
                printk( "contig_page_data.node_zones[3] = [%s] \n",
                        contig_page_data.node_zones[3].name );

输出：
node_data = *c18a0580* 
contig_page_data.node_zones[0] = [DMA] 
contig_page_data.node_zones[1] = [Normal] 
contig_page_data.node_zones[2] = [HighMem] 
contig_page_data.node_zones[3] = [Movable]

记录，便于观看内核的mm

struct zone {
0330         /* Fields commonly accessed by the page allocator  这个域通常被page allocator 访问*/
0331 
0332         /* zone watermarks, access with *_wmark_pages(zone) macros 使用宏访问*/
0333         unsigned long watermark[NR_WMARK];
0334 
0335         /*
0336          * When free pages are below this point, additional steps are taken
0337          * when reading the number of free pages to avoid per-cpu counter
0338          * drift allowing watermarks to be breached
0339          */
0340         unsigned long percpu_drift_mark;
0341 
0342         /*
0343          * We don't know if the memory that we're going to allocate will be freeable
0344          * or/and it will be released eventually, so to avoid totally wasting several
0345          * GB of ram we must reserve some of the lower zone memory (otherwise we risk
0346          * to run OOM on the lower zones despite there's tons of freeable ram
0347          * on the higher zones). This array is recalculated at runtime if the
0348          * sysctl_lowmem_reserve_ratio sysctl changes.
0349          */
0350         unsigned long           lowmem_reserve[MAX_NR_ZONES];
0351 
0352         /*
0353          * This is a per-zone reserve of pages that should not be
0354          * considered dirtyable memory.
0355          */
0356         unsigned long           dirty_balance_reserve;
0357 
0358 #ifdef CONFIG_NUMA
0359         int node;
0360         /*
0361          * zone reclaim becomes active if more unmapped pages exist.
0362          */
0363         unsigned long           min_unmapped_pages;
0364         unsigned long           min_slab_pages;
0365 #endif
0366         struct per_cpu_pageset __percpu *pageset;
0367         /*
0368          * free areas of different sizes
0369          */
0370         spinlock_t              lock;
0371         int                     all_unreclaimable; /* All pages pinned */
0372 #ifdef CONFIG_MEMORY_HOTPLUG
0373         /* see spanned/present_pages for more description */
0374         seqlock_t               span_seqlock;
0375 #endif
0376 #ifdef CONFIG_CMA
0377         /*
0378          * CMA needs to increase watermark levels during the allocation
0379          * process to make sure that the system is not starved.
0380          */
0381         unsigned long           min_cma_pages;
0382 #endif
0383         struct free_area        free_area[MAX_ORDER];
0384 
0385 #ifndef CONFIG_SPARSEMEM
0386         /*
0387          * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
0388          * In SPARSEMEM, this map is stored in struct mem_section
0389          */
0390         unsigned long           *pageblock_flags;
0391 #endif /* CONFIG_SPARSEMEM */
0392 
0393 #ifdef CONFIG_COMPACTION
0394         /*
0395          * On compaction failure, 1<<compact_defer_shift compactions
0396          * are skipped before trying again. The number attempted since
0397          * last failure is tracked with compact_considered.
0398          */
0399         unsigned int            compact_considered;
0400         unsigned int            compact_defer_shift;
0401         int                     compact_order_failed;
0402 #endif
0403 
0404         ZONE_PADDING(_pad1_)
0405 
0406         /* Fields commonly accessed by the page reclaim scanner */
0407         spinlock_t              lru_lock;
0408         struct lruvec           lruvec;
0409 
0410         unsigned long           pages_scanned;     /* since last reclaim */
0411         unsigned long           flags;             /* zone flags, see below */
0412 
0413         /* Zone statistics */
0414         atomic_long_t           vm_stat[NR_VM_ZONE_STAT_ITEMS];
0415 
0416         /*
0417          * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
0418          * this zone's LRU.  Maintained by the pageout code.
0419          */
0420         unsigned int inactive_ratio;
0421 
0422 
0423         ZONE_PADDING(_pad2_)
0424         /* Rarely used or read-mostly fields */
0425 
0426         /*
0427          * wait_table           -- the array holding the hash table
0428          * wait_table_hash_nr_entries   -- the size of the hash table array
0429          * wait_table_bits      -- wait_table_size == (1 << wait_table_bits)
0430          *
0431          * The purpose of all these is to keep track of the people
0432          * waiting for a page to become available and make them
0433          * runnable again when possible. The trouble is that this
0434          * consumes a lot of space, especially when so few things
0435          * wait on pages at a given time. So instead of using
0436          * per-page waitqueues, we use a waitqueue hash table.
0437          *
0438          * The bucket discipline is to sleep on the same queue when
0439          * colliding and wake all in that wait queue when removing.
0440          * When something wakes, it must check to be sure its page is
0441          * truly available, a la thundering herd. The cost of a
0442          * collision is great, but given the expected load of the
0443          * table, they should be so rare as to be outweighed by the
0444          * benefits from the saved space.
0445          *
0446          * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
0447          * primary users of these fields, and in mm/page_alloc.c
0448          * free_area_init_core() performs the initialization of them.
0449          */
0450         wait_queue_head_t       * wait_table;
0451         unsigned long           wait_table_hash_nr_entries;
0452         unsigned long           wait_table_bits;
0453 
0454         /*
0455          * Discontig memory support fields.
0456          */
0457         struct pglist_data      *zone_pgdat;
0458         /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
0459         unsigned long           zone_start_pfn;
0460 
0461         /*
0462          * zone_start_pfn, spanned_pages and present_pages are all
0463          * protected by span_seqlock.  It is a seqlock because it has
0464          * to be read outside of zone->lock, and it is done in the main
0465          * allocator path.  But, it is written quite infrequently.
0466          *
0467          * The lock is declared along with zone->lock because it is
0468          * frequently read in proximity to zone->lock.  It's good to
0469          * give them a chance of being in the same cacheline.
0470          */
0471         unsigned long           spanned_pages;  /* total size, including holes */
0472         unsigned long           present_pages;  /* amount of memory (excluding holes) */
0473 
0474         /*
0475          * rarely used fields:
0476          */
0477         const char              *name;
0478 } ____cacheline_internodealigned_in_smp;


起始帧
zone_start_pfn DMA = 16 
zone_start_pfn NORMAL = 4096 
zone_start_pfn HIGH = 228350 
zone_start_pfn MOVIABLE = 0