2005-04-16 22:20:36 +00:00
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#ifndef _LINUX_MMZONE_H
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#define _LINUX_MMZONE_H
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#ifdef __KERNEL__
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#ifndef __ASSEMBLY__
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#include <linux/config.h>
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#include <linux/spinlock.h>
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#include <linux/list.h>
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#include <linux/wait.h>
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#include <linux/cache.h>
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#include <linux/threads.h>
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#include <linux/numa.h>
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#include <linux/init.h>
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#include <asm/atomic.h>
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/* Free memory management - zoned buddy allocator. */
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#ifndef CONFIG_FORCE_MAX_ZONEORDER
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#define MAX_ORDER 11
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#else
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#define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
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#endif
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struct free_area {
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struct list_head free_list;
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unsigned long nr_free;
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};
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struct pglist_data;
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/*
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* zone->lock and zone->lru_lock are two of the hottest locks in the kernel.
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* So add a wild amount of padding here to ensure that they fall into separate
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* cachelines. There are very few zone structures in the machine, so space
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* consumption is not a concern here.
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*/
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#if defined(CONFIG_SMP)
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struct zone_padding {
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char x[0];
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} ____cacheline_maxaligned_in_smp;
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#define ZONE_PADDING(name) struct zone_padding name;
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#else
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#define ZONE_PADDING(name)
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#endif
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struct per_cpu_pages {
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int count; /* number of pages in the list */
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int low; /* low watermark, refill needed */
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int high; /* high watermark, emptying needed */
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int batch; /* chunk size for buddy add/remove */
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struct list_head list; /* the list of pages */
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};
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struct per_cpu_pageset {
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struct per_cpu_pages pcp[2]; /* 0: hot. 1: cold */
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#ifdef CONFIG_NUMA
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unsigned long numa_hit; /* allocated in intended node */
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unsigned long numa_miss; /* allocated in non intended node */
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unsigned long numa_foreign; /* was intended here, hit elsewhere */
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unsigned long interleave_hit; /* interleaver prefered this zone */
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unsigned long local_node; /* allocation from local node */
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unsigned long other_node; /* allocation from other node */
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#endif
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} ____cacheline_aligned_in_smp;
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2005-06-22 00:14:47 +00:00
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#ifdef CONFIG_NUMA
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#define zone_pcp(__z, __cpu) ((__z)->pageset[(__cpu)])
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#else
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#define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)])
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#endif
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2005-04-16 22:20:36 +00:00
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#define ZONE_DMA 0
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#define ZONE_NORMAL 1
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#define ZONE_HIGHMEM 2
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#define MAX_NR_ZONES 3 /* Sync this with ZONES_SHIFT */
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#define ZONES_SHIFT 2 /* ceil(log2(MAX_NR_ZONES)) */
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/*
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* When a memory allocation must conform to specific limitations (such
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* as being suitable for DMA) the caller will pass in hints to the
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* allocator in the gfp_mask, in the zone modifier bits. These bits
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* are used to select a priority ordered list of memory zones which
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* match the requested limits. GFP_ZONEMASK defines which bits within
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* the gfp_mask should be considered as zone modifiers. Each valid
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* combination of the zone modifier bits has a corresponding list
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* of zones (in node_zonelists). Thus for two zone modifiers there
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* will be a maximum of 4 (2 ** 2) zonelists, for 3 modifiers there will
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* be 8 (2 ** 3) zonelists. GFP_ZONETYPES defines the number of possible
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* combinations of zone modifiers in "zone modifier space".
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*/
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#define GFP_ZONEMASK 0x03
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/*
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* As an optimisation any zone modifier bits which are only valid when
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* no other zone modifier bits are set (loners) should be placed in
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* the highest order bits of this field. This allows us to reduce the
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* extent of the zonelists thus saving space. For example in the case
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* of three zone modifier bits, we could require up to eight zonelists.
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* If the left most zone modifier is a "loner" then the highest valid
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* zonelist would be four allowing us to allocate only five zonelists.
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* Use the first form when the left most bit is not a "loner", otherwise
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* use the second.
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*/
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/* #define GFP_ZONETYPES (GFP_ZONEMASK + 1) */ /* Non-loner */
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#define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */
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/*
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* On machines where it is needed (eg PCs) we divide physical memory
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* into multiple physical zones. On a PC we have 3 zones:
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*
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* ZONE_DMA < 16 MB ISA DMA capable memory
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* ZONE_NORMAL 16-896 MB direct mapped by the kernel
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* ZONE_HIGHMEM > 896 MB only page cache and user processes
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*/
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struct zone {
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/* Fields commonly accessed by the page allocator */
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unsigned long free_pages;
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unsigned long pages_min, pages_low, pages_high;
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/*
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* We don't know if the memory that we're going to allocate will be freeable
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* or/and it will be released eventually, so to avoid totally wasting several
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* GB of ram we must reserve some of the lower zone memory (otherwise we risk
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* to run OOM on the lower zones despite there's tons of freeable ram
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* on the higher zones). This array is recalculated at runtime if the
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* sysctl_lowmem_reserve_ratio sysctl changes.
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*/
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unsigned long lowmem_reserve[MAX_NR_ZONES];
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2005-06-22 00:14:47 +00:00
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#ifdef CONFIG_NUMA
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struct per_cpu_pageset *pageset[NR_CPUS];
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#else
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2005-04-16 22:20:36 +00:00
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struct per_cpu_pageset pageset[NR_CPUS];
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2005-06-22 00:14:47 +00:00
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#endif
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2005-04-16 22:20:36 +00:00
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/*
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* free areas of different sizes
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*/
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spinlock_t lock;
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struct free_area free_area[MAX_ORDER];
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ZONE_PADDING(_pad1_)
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/* Fields commonly accessed by the page reclaim scanner */
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spinlock_t lru_lock;
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struct list_head active_list;
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struct list_head inactive_list;
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unsigned long nr_scan_active;
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unsigned long nr_scan_inactive;
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unsigned long nr_active;
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unsigned long nr_inactive;
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unsigned long pages_scanned; /* since last reclaim */
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int all_unreclaimable; /* All pages pinned */
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2005-06-22 00:14:41 +00:00
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/*
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* Does the allocator try to reclaim pages from the zone as soon
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* as it fails a watermark_ok() in __alloc_pages?
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*/
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int reclaim_pages;
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2005-06-22 00:14:43 +00:00
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/* A count of how many reclaimers are scanning this zone */
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atomic_t reclaim_in_progress;
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2005-06-22 00:14:41 +00:00
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2005-04-16 22:20:36 +00:00
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/*
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* prev_priority holds the scanning priority for this zone. It is
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* defined as the scanning priority at which we achieved our reclaim
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* target at the previous try_to_free_pages() or balance_pgdat()
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* invokation.
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*
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* We use prev_priority as a measure of how much stress page reclaim is
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* under - it drives the swappiness decision: whether to unmap mapped
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* pages.
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*
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* temp_priority is used to remember the scanning priority at which
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* this zone was successfully refilled to free_pages == pages_high.
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*
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* Access to both these fields is quite racy even on uniprocessor. But
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* it is expected to average out OK.
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*/
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int temp_priority;
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int prev_priority;
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ZONE_PADDING(_pad2_)
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/* Rarely used or read-mostly fields */
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/*
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* wait_table -- the array holding the hash table
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* wait_table_size -- the size of the hash table array
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* wait_table_bits -- wait_table_size == (1 << wait_table_bits)
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*
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* The purpose of all these is to keep track of the people
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* waiting for a page to become available and make them
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* runnable again when possible. The trouble is that this
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* consumes a lot of space, especially when so few things
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* wait on pages at a given time. So instead of using
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* per-page waitqueues, we use a waitqueue hash table.
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*
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* The bucket discipline is to sleep on the same queue when
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* colliding and wake all in that wait queue when removing.
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* When something wakes, it must check to be sure its page is
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* truly available, a la thundering herd. The cost of a
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* collision is great, but given the expected load of the
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* table, they should be so rare as to be outweighed by the
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* benefits from the saved space.
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*
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* __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
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* primary users of these fields, and in mm/page_alloc.c
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* free_area_init_core() performs the initialization of them.
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*/
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wait_queue_head_t * wait_table;
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unsigned long wait_table_size;
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unsigned long wait_table_bits;
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/*
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* Discontig memory support fields.
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*/
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struct pglist_data *zone_pgdat;
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struct page *zone_mem_map;
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/* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
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unsigned long zone_start_pfn;
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unsigned long spanned_pages; /* total size, including holes */
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unsigned long present_pages; /* amount of memory (excluding holes) */
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/*
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* rarely used fields:
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*/
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char *name;
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} ____cacheline_maxaligned_in_smp;
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/*
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* The "priority" of VM scanning is how much of the queues we will scan in one
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* go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
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* queues ("queue_length >> 12") during an aging round.
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*/
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#define DEF_PRIORITY 12
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/*
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* One allocation request operates on a zonelist. A zonelist
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* is a list of zones, the first one is the 'goal' of the
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* allocation, the other zones are fallback zones, in decreasing
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* priority.
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*
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* Right now a zonelist takes up less than a cacheline. We never
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* modify it apart from boot-up, and only a few indices are used,
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* so despite the zonelist table being relatively big, the cache
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* footprint of this construct is very small.
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*/
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struct zonelist {
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struct zone *zones[MAX_NUMNODES * MAX_NR_ZONES + 1]; // NULL delimited
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};
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/*
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* The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
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* (mostly NUMA machines?) to denote a higher-level memory zone than the
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* zone denotes.
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*
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* On NUMA machines, each NUMA node would have a pg_data_t to describe
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* it's memory layout.
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*
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* Memory statistics and page replacement data structures are maintained on a
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* per-zone basis.
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*/
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struct bootmem_data;
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typedef struct pglist_data {
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struct zone node_zones[MAX_NR_ZONES];
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struct zonelist node_zonelists[GFP_ZONETYPES];
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int nr_zones;
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[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
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#ifdef CONFIG_FLAT_NODE_MEM_MAP
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2005-04-16 22:20:36 +00:00
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struct page *node_mem_map;
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[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
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#endif
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2005-04-16 22:20:36 +00:00
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struct bootmem_data *bdata;
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unsigned long node_start_pfn;
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unsigned long node_present_pages; /* total number of physical pages */
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unsigned long node_spanned_pages; /* total size of physical page
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range, including holes */
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int node_id;
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struct pglist_data *pgdat_next;
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wait_queue_head_t kswapd_wait;
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struct task_struct *kswapd;
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int kswapd_max_order;
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} pg_data_t;
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|
|
|
#define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
|
|
|
|
#define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#ifdef CONFIG_FLAT_NODE_MEM_MAP
|
[PATCH] remove non-DISCONTIG use of pgdat->node_mem_map
This patch effectively eliminates direct use of pgdat->node_mem_map outside
of the DISCONTIG code. On a flat memory system, these fields aren't
currently used, neither are they on a sparsemem system.
There was also a node_mem_map(nid) macro on many architectures. Its use
along with the use of ->node_mem_map itself was not consistent. It has
been removed in favor of two new, more explicit, arch-independent macros:
pgdat_page_nr(pgdat, pagenr)
nid_page_nr(nid, pagenr)
I called them "pgdat" and "nid" because we overload the term "node" to mean
"NUMA node", "DISCONTIG node" or "pg_data_t" in very confusing ways. I
believe the newer names are much clearer.
These macros can be overridden in the sparsemem case with a theoretically
slower operation using node_start_pfn and pfn_to_page(), instead. We could
make this the only behavior if people want, but I don't want to change too
much at once. One thing at a time.
This patch removes more code than it adds.
Compile tested on alpha, alpha discontig, arm, arm-discontig, i386, i386
generic, NUMAQ, Summit, ppc64, ppc64 discontig, and x86_64. Full list
here: http://sr71.net/patches/2.6.12/2.6.12-rc1-mhp2/configs/
Boot tested on NUMAQ, x86 SMP and ppc64 power4/5 LPARs.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin J. Bligh <mbligh@aracnet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:37 +00:00
|
|
|
#define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#else
|
|
|
|
#define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
|
|
|
|
#endif
|
[PATCH] remove non-DISCONTIG use of pgdat->node_mem_map
This patch effectively eliminates direct use of pgdat->node_mem_map outside
of the DISCONTIG code. On a flat memory system, these fields aren't
currently used, neither are they on a sparsemem system.
There was also a node_mem_map(nid) macro on many architectures. Its use
along with the use of ->node_mem_map itself was not consistent. It has
been removed in favor of two new, more explicit, arch-independent macros:
pgdat_page_nr(pgdat, pagenr)
nid_page_nr(nid, pagenr)
I called them "pgdat" and "nid" because we overload the term "node" to mean
"NUMA node", "DISCONTIG node" or "pg_data_t" in very confusing ways. I
believe the newer names are much clearer.
These macros can be overridden in the sparsemem case with a theoretically
slower operation using node_start_pfn and pfn_to_page(), instead. We could
make this the only behavior if people want, but I don't want to change too
much at once. One thing at a time.
This patch removes more code than it adds.
Compile tested on alpha, alpha discontig, arm, arm-discontig, i386, i386
generic, NUMAQ, Summit, ppc64, ppc64 discontig, and x86_64. Full list
here: http://sr71.net/patches/2.6.12/2.6.12-rc1-mhp2/configs/
Boot tested on NUMAQ, x86 SMP and ppc64 power4/5 LPARs.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin J. Bligh <mbligh@aracnet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:37 +00:00
|
|
|
#define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
extern struct pglist_data *pgdat_list;
|
|
|
|
|
|
|
|
void __get_zone_counts(unsigned long *active, unsigned long *inactive,
|
|
|
|
unsigned long *free, struct pglist_data *pgdat);
|
|
|
|
void get_zone_counts(unsigned long *active, unsigned long *inactive,
|
|
|
|
unsigned long *free);
|
|
|
|
void build_all_zonelists(void);
|
|
|
|
void wakeup_kswapd(struct zone *zone, int order);
|
|
|
|
int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
|
|
|
|
int alloc_type, int can_try_harder, int gfp_high);
|
|
|
|
|
|
|
|
#ifdef CONFIG_HAVE_MEMORY_PRESENT
|
|
|
|
void memory_present(int nid, unsigned long start, unsigned long end);
|
|
|
|
#else
|
|
|
|
static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
|
|
|
|
unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
|
|
|
|
*/
|
|
|
|
#define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
|
|
|
|
|
|
|
|
/**
|
|
|
|
* for_each_pgdat - helper macro to iterate over all nodes
|
|
|
|
* @pgdat - pointer to a pg_data_t variable
|
|
|
|
*
|
|
|
|
* Meant to help with common loops of the form
|
|
|
|
* pgdat = pgdat_list;
|
|
|
|
* while(pgdat) {
|
|
|
|
* ...
|
|
|
|
* pgdat = pgdat->pgdat_next;
|
|
|
|
* }
|
|
|
|
*/
|
|
|
|
#define for_each_pgdat(pgdat) \
|
|
|
|
for (pgdat = pgdat_list; pgdat; pgdat = pgdat->pgdat_next)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* next_zone - helper magic for for_each_zone()
|
|
|
|
* Thanks to William Lee Irwin III for this piece of ingenuity.
|
|
|
|
*/
|
|
|
|
static inline struct zone *next_zone(struct zone *zone)
|
|
|
|
{
|
|
|
|
pg_data_t *pgdat = zone->zone_pgdat;
|
|
|
|
|
|
|
|
if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
|
|
|
|
zone++;
|
|
|
|
else if (pgdat->pgdat_next) {
|
|
|
|
pgdat = pgdat->pgdat_next;
|
|
|
|
zone = pgdat->node_zones;
|
|
|
|
} else
|
|
|
|
zone = NULL;
|
|
|
|
|
|
|
|
return zone;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* for_each_zone - helper macro to iterate over all memory zones
|
|
|
|
* @zone - pointer to struct zone variable
|
|
|
|
*
|
|
|
|
* The user only needs to declare the zone variable, for_each_zone
|
|
|
|
* fills it in. This basically means for_each_zone() is an
|
|
|
|
* easier to read version of this piece of code:
|
|
|
|
*
|
|
|
|
* for (pgdat = pgdat_list; pgdat; pgdat = pgdat->node_next)
|
|
|
|
* for (i = 0; i < MAX_NR_ZONES; ++i) {
|
|
|
|
* struct zone * z = pgdat->node_zones + i;
|
|
|
|
* ...
|
|
|
|
* }
|
|
|
|
* }
|
|
|
|
*/
|
|
|
|
#define for_each_zone(zone) \
|
|
|
|
for (zone = pgdat_list->node_zones; zone; zone = next_zone(zone))
|
|
|
|
|
|
|
|
static inline int is_highmem_idx(int idx)
|
|
|
|
{
|
|
|
|
return (idx == ZONE_HIGHMEM);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int is_normal_idx(int idx)
|
|
|
|
{
|
|
|
|
return (idx == ZONE_NORMAL);
|
|
|
|
}
|
|
|
|
/**
|
|
|
|
* is_highmem - helper function to quickly check if a struct zone is a
|
|
|
|
* highmem zone or not. This is an attempt to keep references
|
|
|
|
* to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
|
|
|
|
* @zone - pointer to struct zone variable
|
|
|
|
*/
|
|
|
|
static inline int is_highmem(struct zone *zone)
|
|
|
|
{
|
|
|
|
return zone == zone->zone_pgdat->node_zones + ZONE_HIGHMEM;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int is_normal(struct zone *zone)
|
|
|
|
{
|
|
|
|
return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* These two functions are used to setup the per zone pages min values */
|
|
|
|
struct ctl_table;
|
|
|
|
struct file;
|
|
|
|
int min_free_kbytes_sysctl_handler(struct ctl_table *, int, struct file *,
|
|
|
|
void __user *, size_t *, loff_t *);
|
|
|
|
extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
|
|
|
|
int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, struct file *,
|
|
|
|
void __user *, size_t *, loff_t *);
|
|
|
|
|
|
|
|
#include <linux/topology.h>
|
|
|
|
/* Returns the number of the current Node. */
|
2005-06-22 00:14:34 +00:00
|
|
|
#define numa_node_id() (cpu_to_node(raw_smp_processor_id()))
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2005-06-23 07:07:47 +00:00
|
|
|
#ifndef CONFIG_NEED_MULTIPLE_NODES
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
extern struct pglist_data contig_page_data;
|
|
|
|
#define NODE_DATA(nid) (&contig_page_data)
|
|
|
|
#define NODE_MEM_MAP(nid) mem_map
|
|
|
|
#define MAX_NODES_SHIFT 1
|
|
|
|
#define pfn_to_nid(pfn) (0)
|
|
|
|
|
2005-06-23 07:07:47 +00:00
|
|
|
#else /* CONFIG_NEED_MULTIPLE_NODES */
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
#include <asm/mmzone.h>
|
|
|
|
|
2005-06-23 07:07:47 +00:00
|
|
|
#endif /* !CONFIG_NEED_MULTIPLE_NODES */
|
2005-06-23 07:07:40 +00:00
|
|
|
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#ifdef CONFIG_SPARSEMEM
|
|
|
|
#include <asm/sparsemem.h>
|
|
|
|
#endif
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#if BITS_PER_LONG == 32 || defined(ARCH_HAS_ATOMIC_UNSIGNED)
|
|
|
|
/*
|
|
|
|
* with 32 bit page->flags field, we reserve 8 bits for node/zone info.
|
|
|
|
* there are 3 zones (2 bits) and this leaves 8-2=6 bits for nodes.
|
|
|
|
*/
|
2005-06-23 07:07:40 +00:00
|
|
|
#define FLAGS_RESERVED 8
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
#elif BITS_PER_LONG == 64
|
|
|
|
/*
|
|
|
|
* with 64 bit flags field, there's plenty of room.
|
|
|
|
*/
|
2005-06-23 07:07:40 +00:00
|
|
|
#define FLAGS_RESERVED 32
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2005-06-23 07:07:40 +00:00
|
|
|
#else
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2005-06-23 07:07:40 +00:00
|
|
|
#error BITS_PER_LONG not defined
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
#endif
|
|
|
|
|
2005-06-23 07:07:52 +00:00
|
|
|
#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
|
|
|
|
#define early_pfn_to_nid(nid) (0UL)
|
|
|
|
#endif
|
|
|
|
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
|
|
|
|
#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
|
|
|
|
|
|
|
|
#ifdef CONFIG_SPARSEMEM
|
|
|
|
|
|
|
|
/*
|
|
|
|
* SECTION_SHIFT #bits space required to store a section #
|
|
|
|
*
|
|
|
|
* PA_SECTION_SHIFT physical address to/from section number
|
|
|
|
* PFN_SECTION_SHIFT pfn to/from section number
|
|
|
|
*/
|
|
|
|
#define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
|
|
|
|
|
|
|
|
#define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
|
|
|
|
#define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
|
|
|
|
|
|
|
|
#define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
|
|
|
|
|
|
|
|
#define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
|
|
|
|
#define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
|
|
|
|
|
|
|
|
#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
|
|
|
|
#error Allocator MAX_ORDER exceeds SECTION_SIZE
|
|
|
|
#endif
|
|
|
|
|
|
|
|
struct page;
|
|
|
|
struct mem_section {
|
2005-06-23 07:08:00 +00:00
|
|
|
/*
|
|
|
|
* This is, logically, a pointer to an array of struct
|
|
|
|
* pages. However, it is stored with some other magic.
|
|
|
|
* (see sparse.c::sparse_init_one_section())
|
|
|
|
*
|
|
|
|
* Making it a UL at least makes someone do a cast
|
|
|
|
* before using it wrong.
|
|
|
|
*/
|
|
|
|
unsigned long section_mem_map;
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
};
|
|
|
|
|
2005-09-03 22:54:28 +00:00
|
|
|
#ifdef CONFIG_SPARSEMEM_EXTREME
|
|
|
|
#define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
|
|
|
|
#else
|
|
|
|
#define SECTIONS_PER_ROOT 1
|
|
|
|
#endif
|
2005-09-03 22:54:26 +00:00
|
|
|
|
2005-09-03 22:54:28 +00:00
|
|
|
#define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
|
|
|
|
#define NR_SECTION_ROOTS (NR_MEM_SECTIONS / SECTIONS_PER_ROOT)
|
|
|
|
#define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
|
2005-09-03 22:54:26 +00:00
|
|
|
|
2005-09-03 22:54:28 +00:00
|
|
|
#ifdef CONFIG_SPARSEMEM_EXTREME
|
|
|
|
extern struct mem_section *mem_section[NR_SECTION_ROOTS];
|
2005-09-03 22:54:26 +00:00
|
|
|
#else
|
2005-09-03 22:54:28 +00:00
|
|
|
extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
|
|
|
|
#endif
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
|
2005-06-23 07:08:00 +00:00
|
|
|
static inline struct mem_section *__nr_to_section(unsigned long nr)
|
|
|
|
{
|
2005-09-03 22:54:28 +00:00
|
|
|
if (!mem_section[SECTION_NR_TO_ROOT(nr)])
|
|
|
|
return NULL;
|
|
|
|
return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
|
2005-06-23 07:08:00 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We use the lower bits of the mem_map pointer to store
|
|
|
|
* a little bit of information. There should be at least
|
|
|
|
* 3 bits here due to 32-bit alignment.
|
|
|
|
*/
|
|
|
|
#define SECTION_MARKED_PRESENT (1UL<<0)
|
|
|
|
#define SECTION_HAS_MEM_MAP (1UL<<1)
|
|
|
|
#define SECTION_MAP_LAST_BIT (1UL<<2)
|
|
|
|
#define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
|
|
|
|
|
|
|
|
static inline struct page *__section_mem_map_addr(struct mem_section *section)
|
|
|
|
{
|
|
|
|
unsigned long map = section->section_mem_map;
|
|
|
|
map &= SECTION_MAP_MASK;
|
|
|
|
return (struct page *)map;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int valid_section(struct mem_section *section)
|
|
|
|
{
|
2005-09-03 22:54:26 +00:00
|
|
|
return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
|
2005-06-23 07:08:00 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline int section_has_mem_map(struct mem_section *section)
|
|
|
|
{
|
2005-09-03 22:54:26 +00:00
|
|
|
return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
|
2005-06-23 07:08:00 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline int valid_section_nr(unsigned long nr)
|
|
|
|
{
|
|
|
|
return valid_section(__nr_to_section(nr));
|
|
|
|
}
|
|
|
|
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
/*
|
|
|
|
* Given a kernel address, find the home node of the underlying memory.
|
|
|
|
*/
|
|
|
|
#define kvaddr_to_nid(kaddr) pfn_to_nid(__pa(kaddr) >> PAGE_SHIFT)
|
|
|
|
|
|
|
|
static inline struct mem_section *__pfn_to_section(unsigned long pfn)
|
|
|
|
{
|
2005-06-23 07:08:00 +00:00
|
|
|
return __nr_to_section(pfn_to_section_nr(pfn));
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
#define pfn_to_page(pfn) \
|
|
|
|
({ \
|
|
|
|
unsigned long __pfn = (pfn); \
|
2005-06-23 07:08:00 +00:00
|
|
|
__section_mem_map_addr(__pfn_to_section(__pfn)) + __pfn; \
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
})
|
|
|
|
#define page_to_pfn(page) \
|
|
|
|
({ \
|
2005-06-23 07:08:00 +00:00
|
|
|
page - __section_mem_map_addr(__nr_to_section( \
|
|
|
|
page_to_section(page))); \
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
})
|
|
|
|
|
|
|
|
static inline int pfn_valid(unsigned long pfn)
|
|
|
|
{
|
|
|
|
if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
|
|
|
|
return 0;
|
2005-06-23 07:08:00 +00:00
|
|
|
return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
|
[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
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* These are _only_ used during initialisation, therefore they
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* can use __initdata ... They could have names to indicate
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* this restriction.
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*/
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#ifdef CONFIG_NUMA
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#define pfn_to_nid early_pfn_to_nid
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#endif
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#define pfn_to_pgdat(pfn) \
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({ \
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NODE_DATA(pfn_to_nid(pfn)); \
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})
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#define early_pfn_valid(pfn) pfn_valid(pfn)
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void sparse_init(void);
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#else
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#define sparse_init() do {} while (0)
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#endif /* CONFIG_SPARSEMEM */
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[PATCH] sparsemem swiss cheese numa layouts
The part of the sparsemem patch which modifies memmap_init_zone() has recently
become a problem. It changes behavior so that there is a call to
pfn_to_page() for each individual page inside of a node's range:
node_start_pfn through node_end_pfn. It used to simply do this once, at the
beginning of the node, but having sparsemem's non-contiguous mem_map[]s inside
of a node made it necessary to change.
Mike Kravetz recently wrote a patch which made the NUMA code accept some new
kinds of layouts. The system's memory was laid out like this, with node 0's
memory in two pieces: one before and one after node 1's memory:
Node 0: +++++ +++++
Node 1: +++++
Previous behavior before Mike's patch was to assign nodes like this:
Node 0: 00000 XXXXX
Node 1: 11111
Where the 'X' areas were simply thrown away. The new behavior was to make the
pg_data_t span node 0 across all of its areas, including areas that are really
node 1's: Node 0: 000000000000000 Node 1: 11111
This wastes a little bit of mem_map space, but ends up being OK, and more
fully utilizes the system's memory. memmap_init_zone() initializes all of the
"struct page"s for node 0, even for the "hole", but those never get used,
because there is no pfn_to_page() that resolves to those pages. However, only
calling pfn_to_page() once, memmap_init_zone() always uses the pages that were
allocated for node0->node_mem_map because:
struct page *start = pfn_to_page(start_pfn);
// effectively start = &node->node_mem_map[0]
for (page = start; page < (start + size); page++) {
init_page_here();...
page++;
}
Slow, and wasteful, but generally harmless.
But, modify that to call pfn_to_page() for each loop iteration (like sparsemem
does):
for (pfn = start_pfn; pfn < < (start_pfn + size); pfn++++) {
page = pfn_to_page(pfn);
}
And you end up trying to initialize node 1's pages too early, along with bogus
data from node 0. This patch checks for those weird layouts and declines to
touch the pages, making the more frequent pfn_to_page() calls OK to do.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:59 +00:00
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#ifdef CONFIG_NODES_SPAN_OTHER_NODES
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#define early_pfn_in_nid(pfn, nid) (early_pfn_to_nid(pfn) == (nid))
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#else
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#define early_pfn_in_nid(pfn, nid) (1)
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#endif
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[PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[]. This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems. Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.
A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA. When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.
Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous. It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.
Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory. This is what allows the mem_map[]
to be chopped up.
In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags. Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations. However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions. Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.
One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags. It might provide
speed increases on certain platforms and will be stored there if there is
room. But, if out of room, an alternate (theoretically slower) mechanism is
used.
This patch introduces CONFIG_FLATMEM. It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 07:07:54 +00:00
|
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#ifndef early_pfn_valid
|
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|
#define early_pfn_valid(pfn) (1)
|
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#endif
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void memory_present(int nid, unsigned long start, unsigned long end);
|
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|
unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
|
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2005-04-16 22:20:36 +00:00
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#endif /* !__ASSEMBLY__ */
|
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#endif /* __KERNEL__ */
|
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|
#endif /* _LINUX_MMZONE_H */
|