mirror of
https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git
synced 2026-10-30 11:41:38 -04:00
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
This commit is contained in:
Linus Torvalds
commit
1da177e4c3
17291 changed files with 6718755 additions and 0 deletions
485
mm/swap.c
Normal file
485
mm/swap.c
Normal file
|
|
@ -0,0 +1,485 @@
|
|||
/*
|
||||
* linux/mm/swap.c
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||||
*
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||||
* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
|
||||
*/
|
||||
|
||||
/*
|
||||
* This file contains the default values for the opereation of the
|
||||
* Linux VM subsystem. Fine-tuning documentation can be found in
|
||||
* Documentation/sysctl/vm.txt.
|
||||
* Started 18.12.91
|
||||
* Swap aging added 23.2.95, Stephen Tweedie.
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||||
* Buffermem limits added 12.3.98, Rik van Riel.
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||||
*/
|
||||
|
||||
#include <linux/mm.h>
|
||||
#include <linux/sched.h>
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||||
#include <linux/kernel_stat.h>
|
||||
#include <linux/swap.h>
|
||||
#include <linux/mman.h>
|
||||
#include <linux/pagemap.h>
|
||||
#include <linux/pagevec.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mm_inline.h>
|
||||
#include <linux/buffer_head.h> /* for try_to_release_page() */
|
||||
#include <linux/module.h>
|
||||
#include <linux/percpu_counter.h>
|
||||
#include <linux/percpu.h>
|
||||
#include <linux/cpu.h>
|
||||
#include <linux/notifier.h>
|
||||
#include <linux/init.h>
|
||||
|
||||
/* How many pages do we try to swap or page in/out together? */
|
||||
int page_cluster;
|
||||
|
||||
#ifdef CONFIG_HUGETLB_PAGE
|
||||
|
||||
void put_page(struct page *page)
|
||||
{
|
||||
if (unlikely(PageCompound(page))) {
|
||||
page = (struct page *)page->private;
|
||||
if (put_page_testzero(page)) {
|
||||
void (*dtor)(struct page *page);
|
||||
|
||||
dtor = (void (*)(struct page *))page[1].mapping;
|
||||
(*dtor)(page);
|
||||
}
|
||||
return;
|
||||
}
|
||||
if (!PageReserved(page) && put_page_testzero(page))
|
||||
__page_cache_release(page);
|
||||
}
|
||||
EXPORT_SYMBOL(put_page);
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Writeback is about to end against a page which has been marked for immediate
|
||||
* reclaim. If it still appears to be reclaimable, move it to the tail of the
|
||||
* inactive list. The page still has PageWriteback set, which will pin it.
|
||||
*
|
||||
* We don't expect many pages to come through here, so don't bother batching
|
||||
* things up.
|
||||
*
|
||||
* To avoid placing the page at the tail of the LRU while PG_writeback is still
|
||||
* set, this function will clear PG_writeback before performing the page
|
||||
* motion. Do that inside the lru lock because once PG_writeback is cleared
|
||||
* we may not touch the page.
|
||||
*
|
||||
* Returns zero if it cleared PG_writeback.
|
||||
*/
|
||||
int rotate_reclaimable_page(struct page *page)
|
||||
{
|
||||
struct zone *zone;
|
||||
unsigned long flags;
|
||||
|
||||
if (PageLocked(page))
|
||||
return 1;
|
||||
if (PageDirty(page))
|
||||
return 1;
|
||||
if (PageActive(page))
|
||||
return 1;
|
||||
if (!PageLRU(page))
|
||||
return 1;
|
||||
|
||||
zone = page_zone(page);
|
||||
spin_lock_irqsave(&zone->lru_lock, flags);
|
||||
if (PageLRU(page) && !PageActive(page)) {
|
||||
list_del(&page->lru);
|
||||
list_add_tail(&page->lru, &zone->inactive_list);
|
||||
inc_page_state(pgrotated);
|
||||
}
|
||||
if (!test_clear_page_writeback(page))
|
||||
BUG();
|
||||
spin_unlock_irqrestore(&zone->lru_lock, flags);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* FIXME: speed this up?
|
||||
*/
|
||||
void fastcall activate_page(struct page *page)
|
||||
{
|
||||
struct zone *zone = page_zone(page);
|
||||
|
||||
spin_lock_irq(&zone->lru_lock);
|
||||
if (PageLRU(page) && !PageActive(page)) {
|
||||
del_page_from_inactive_list(zone, page);
|
||||
SetPageActive(page);
|
||||
add_page_to_active_list(zone, page);
|
||||
inc_page_state(pgactivate);
|
||||
}
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* Mark a page as having seen activity.
|
||||
*
|
||||
* inactive,unreferenced -> inactive,referenced
|
||||
* inactive,referenced -> active,unreferenced
|
||||
* active,unreferenced -> active,referenced
|
||||
*/
|
||||
void fastcall mark_page_accessed(struct page *page)
|
||||
{
|
||||
if (!PageActive(page) && PageReferenced(page) && PageLRU(page)) {
|
||||
activate_page(page);
|
||||
ClearPageReferenced(page);
|
||||
} else if (!PageReferenced(page)) {
|
||||
SetPageReferenced(page);
|
||||
}
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(mark_page_accessed);
|
||||
|
||||
/**
|
||||
* lru_cache_add: add a page to the page lists
|
||||
* @page: the page to add
|
||||
*/
|
||||
static DEFINE_PER_CPU(struct pagevec, lru_add_pvecs) = { 0, };
|
||||
static DEFINE_PER_CPU(struct pagevec, lru_add_active_pvecs) = { 0, };
|
||||
|
||||
void fastcall lru_cache_add(struct page *page)
|
||||
{
|
||||
struct pagevec *pvec = &get_cpu_var(lru_add_pvecs);
|
||||
|
||||
page_cache_get(page);
|
||||
if (!pagevec_add(pvec, page))
|
||||
__pagevec_lru_add(pvec);
|
||||
put_cpu_var(lru_add_pvecs);
|
||||
}
|
||||
|
||||
void fastcall lru_cache_add_active(struct page *page)
|
||||
{
|
||||
struct pagevec *pvec = &get_cpu_var(lru_add_active_pvecs);
|
||||
|
||||
page_cache_get(page);
|
||||
if (!pagevec_add(pvec, page))
|
||||
__pagevec_lru_add_active(pvec);
|
||||
put_cpu_var(lru_add_active_pvecs);
|
||||
}
|
||||
|
||||
void lru_add_drain(void)
|
||||
{
|
||||
struct pagevec *pvec = &get_cpu_var(lru_add_pvecs);
|
||||
|
||||
if (pagevec_count(pvec))
|
||||
__pagevec_lru_add(pvec);
|
||||
pvec = &__get_cpu_var(lru_add_active_pvecs);
|
||||
if (pagevec_count(pvec))
|
||||
__pagevec_lru_add_active(pvec);
|
||||
put_cpu_var(lru_add_pvecs);
|
||||
}
|
||||
|
||||
/*
|
||||
* This path almost never happens for VM activity - pages are normally
|
||||
* freed via pagevecs. But it gets used by networking.
|
||||
*/
|
||||
void fastcall __page_cache_release(struct page *page)
|
||||
{
|
||||
unsigned long flags;
|
||||
struct zone *zone = page_zone(page);
|
||||
|
||||
spin_lock_irqsave(&zone->lru_lock, flags);
|
||||
if (TestClearPageLRU(page))
|
||||
del_page_from_lru(zone, page);
|
||||
if (page_count(page) != 0)
|
||||
page = NULL;
|
||||
spin_unlock_irqrestore(&zone->lru_lock, flags);
|
||||
if (page)
|
||||
free_hot_page(page);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(__page_cache_release);
|
||||
|
||||
/*
|
||||
* Batched page_cache_release(). Decrement the reference count on all the
|
||||
* passed pages. If it fell to zero then remove the page from the LRU and
|
||||
* free it.
|
||||
*
|
||||
* Avoid taking zone->lru_lock if possible, but if it is taken, retain it
|
||||
* for the remainder of the operation.
|
||||
*
|
||||
* The locking in this function is against shrink_cache(): we recheck the
|
||||
* page count inside the lock to see whether shrink_cache grabbed the page
|
||||
* via the LRU. If it did, give up: shrink_cache will free it.
|
||||
*/
|
||||
void release_pages(struct page **pages, int nr, int cold)
|
||||
{
|
||||
int i;
|
||||
struct pagevec pages_to_free;
|
||||
struct zone *zone = NULL;
|
||||
|
||||
pagevec_init(&pages_to_free, cold);
|
||||
for (i = 0; i < nr; i++) {
|
||||
struct page *page = pages[i];
|
||||
struct zone *pagezone;
|
||||
|
||||
if (PageReserved(page) || !put_page_testzero(page))
|
||||
continue;
|
||||
|
||||
pagezone = page_zone(page);
|
||||
if (pagezone != zone) {
|
||||
if (zone)
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
zone = pagezone;
|
||||
spin_lock_irq(&zone->lru_lock);
|
||||
}
|
||||
if (TestClearPageLRU(page))
|
||||
del_page_from_lru(zone, page);
|
||||
if (page_count(page) == 0) {
|
||||
if (!pagevec_add(&pages_to_free, page)) {
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
__pagevec_free(&pages_to_free);
|
||||
pagevec_reinit(&pages_to_free);
|
||||
zone = NULL; /* No lock is held */
|
||||
}
|
||||
}
|
||||
}
|
||||
if (zone)
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
|
||||
pagevec_free(&pages_to_free);
|
||||
}
|
||||
|
||||
/*
|
||||
* The pages which we're about to release may be in the deferred lru-addition
|
||||
* queues. That would prevent them from really being freed right now. That's
|
||||
* OK from a correctness point of view but is inefficient - those pages may be
|
||||
* cache-warm and we want to give them back to the page allocator ASAP.
|
||||
*
|
||||
* So __pagevec_release() will drain those queues here. __pagevec_lru_add()
|
||||
* and __pagevec_lru_add_active() call release_pages() directly to avoid
|
||||
* mutual recursion.
|
||||
*/
|
||||
void __pagevec_release(struct pagevec *pvec)
|
||||
{
|
||||
lru_add_drain();
|
||||
release_pages(pvec->pages, pagevec_count(pvec), pvec->cold);
|
||||
pagevec_reinit(pvec);
|
||||
}
|
||||
|
||||
/*
|
||||
* pagevec_release() for pages which are known to not be on the LRU
|
||||
*
|
||||
* This function reinitialises the caller's pagevec.
|
||||
*/
|
||||
void __pagevec_release_nonlru(struct pagevec *pvec)
|
||||
{
|
||||
int i;
|
||||
struct pagevec pages_to_free;
|
||||
|
||||
pagevec_init(&pages_to_free, pvec->cold);
|
||||
pages_to_free.cold = pvec->cold;
|
||||
for (i = 0; i < pagevec_count(pvec); i++) {
|
||||
struct page *page = pvec->pages[i];
|
||||
|
||||
BUG_ON(PageLRU(page));
|
||||
if (put_page_testzero(page))
|
||||
pagevec_add(&pages_to_free, page);
|
||||
}
|
||||
pagevec_free(&pages_to_free);
|
||||
pagevec_reinit(pvec);
|
||||
}
|
||||
|
||||
/*
|
||||
* Add the passed pages to the LRU, then drop the caller's refcount
|
||||
* on them. Reinitialises the caller's pagevec.
|
||||
*/
|
||||
void __pagevec_lru_add(struct pagevec *pvec)
|
||||
{
|
||||
int i;
|
||||
struct zone *zone = NULL;
|
||||
|
||||
for (i = 0; i < pagevec_count(pvec); i++) {
|
||||
struct page *page = pvec->pages[i];
|
||||
struct zone *pagezone = page_zone(page);
|
||||
|
||||
if (pagezone != zone) {
|
||||
if (zone)
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
zone = pagezone;
|
||||
spin_lock_irq(&zone->lru_lock);
|
||||
}
|
||||
if (TestSetPageLRU(page))
|
||||
BUG();
|
||||
add_page_to_inactive_list(zone, page);
|
||||
}
|
||||
if (zone)
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
release_pages(pvec->pages, pvec->nr, pvec->cold);
|
||||
pagevec_reinit(pvec);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(__pagevec_lru_add);
|
||||
|
||||
void __pagevec_lru_add_active(struct pagevec *pvec)
|
||||
{
|
||||
int i;
|
||||
struct zone *zone = NULL;
|
||||
|
||||
for (i = 0; i < pagevec_count(pvec); i++) {
|
||||
struct page *page = pvec->pages[i];
|
||||
struct zone *pagezone = page_zone(page);
|
||||
|
||||
if (pagezone != zone) {
|
||||
if (zone)
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
zone = pagezone;
|
||||
spin_lock_irq(&zone->lru_lock);
|
||||
}
|
||||
if (TestSetPageLRU(page))
|
||||
BUG();
|
||||
if (TestSetPageActive(page))
|
||||
BUG();
|
||||
add_page_to_active_list(zone, page);
|
||||
}
|
||||
if (zone)
|
||||
spin_unlock_irq(&zone->lru_lock);
|
||||
release_pages(pvec->pages, pvec->nr, pvec->cold);
|
||||
pagevec_reinit(pvec);
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to drop buffers from the pages in a pagevec
|
||||
*/
|
||||
void pagevec_strip(struct pagevec *pvec)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < pagevec_count(pvec); i++) {
|
||||
struct page *page = pvec->pages[i];
|
||||
|
||||
if (PagePrivate(page) && !TestSetPageLocked(page)) {
|
||||
try_to_release_page(page, 0);
|
||||
unlock_page(page);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* pagevec_lookup - gang pagecache lookup
|
||||
* @pvec: Where the resulting pages are placed
|
||||
* @mapping: The address_space to search
|
||||
* @start: The starting page index
|
||||
* @nr_pages: The maximum number of pages
|
||||
*
|
||||
* pagevec_lookup() will search for and return a group of up to @nr_pages pages
|
||||
* in the mapping. The pages are placed in @pvec. pagevec_lookup() takes a
|
||||
* reference against the pages in @pvec.
|
||||
*
|
||||
* The search returns a group of mapping-contiguous pages with ascending
|
||||
* indexes. There may be holes in the indices due to not-present pages.
|
||||
*
|
||||
* pagevec_lookup() returns the number of pages which were found.
|
||||
*/
|
||||
unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
|
||||
pgoff_t start, unsigned nr_pages)
|
||||
{
|
||||
pvec->nr = find_get_pages(mapping, start, nr_pages, pvec->pages);
|
||||
return pagevec_count(pvec);
|
||||
}
|
||||
|
||||
unsigned pagevec_lookup_tag(struct pagevec *pvec, struct address_space *mapping,
|
||||
pgoff_t *index, int tag, unsigned nr_pages)
|
||||
{
|
||||
pvec->nr = find_get_pages_tag(mapping, index, tag,
|
||||
nr_pages, pvec->pages);
|
||||
return pagevec_count(pvec);
|
||||
}
|
||||
|
||||
|
||||
#ifdef CONFIG_SMP
|
||||
/*
|
||||
* We tolerate a little inaccuracy to avoid ping-ponging the counter between
|
||||
* CPUs
|
||||
*/
|
||||
#define ACCT_THRESHOLD max(16, NR_CPUS * 2)
|
||||
|
||||
static DEFINE_PER_CPU(long, committed_space) = 0;
|
||||
|
||||
void vm_acct_memory(long pages)
|
||||
{
|
||||
long *local;
|
||||
|
||||
preempt_disable();
|
||||
local = &__get_cpu_var(committed_space);
|
||||
*local += pages;
|
||||
if (*local > ACCT_THRESHOLD || *local < -ACCT_THRESHOLD) {
|
||||
atomic_add(*local, &vm_committed_space);
|
||||
*local = 0;
|
||||
}
|
||||
preempt_enable();
|
||||
}
|
||||
EXPORT_SYMBOL(vm_acct_memory);
|
||||
|
||||
#ifdef CONFIG_HOTPLUG_CPU
|
||||
static void lru_drain_cache(unsigned int cpu)
|
||||
{
|
||||
struct pagevec *pvec = &per_cpu(lru_add_pvecs, cpu);
|
||||
|
||||
/* CPU is dead, so no locking needed. */
|
||||
if (pagevec_count(pvec))
|
||||
__pagevec_lru_add(pvec);
|
||||
pvec = &per_cpu(lru_add_active_pvecs, cpu);
|
||||
if (pagevec_count(pvec))
|
||||
__pagevec_lru_add_active(pvec);
|
||||
}
|
||||
|
||||
/* Drop the CPU's cached committed space back into the central pool. */
|
||||
static int cpu_swap_callback(struct notifier_block *nfb,
|
||||
unsigned long action,
|
||||
void *hcpu)
|
||||
{
|
||||
long *committed;
|
||||
|
||||
committed = &per_cpu(committed_space, (long)hcpu);
|
||||
if (action == CPU_DEAD) {
|
||||
atomic_add(*committed, &vm_committed_space);
|
||||
*committed = 0;
|
||||
lru_drain_cache((long)hcpu);
|
||||
}
|
||||
return NOTIFY_OK;
|
||||
}
|
||||
#endif /* CONFIG_HOTPLUG_CPU */
|
||||
#endif /* CONFIG_SMP */
|
||||
|
||||
#ifdef CONFIG_SMP
|
||||
void percpu_counter_mod(struct percpu_counter *fbc, long amount)
|
||||
{
|
||||
long count;
|
||||
long *pcount;
|
||||
int cpu = get_cpu();
|
||||
|
||||
pcount = per_cpu_ptr(fbc->counters, cpu);
|
||||
count = *pcount + amount;
|
||||
if (count >= FBC_BATCH || count <= -FBC_BATCH) {
|
||||
spin_lock(&fbc->lock);
|
||||
fbc->count += count;
|
||||
spin_unlock(&fbc->lock);
|
||||
count = 0;
|
||||
}
|
||||
*pcount = count;
|
||||
put_cpu();
|
||||
}
|
||||
EXPORT_SYMBOL(percpu_counter_mod);
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Perform any setup for the swap system
|
||||
*/
|
||||
void __init swap_setup(void)
|
||||
{
|
||||
unsigned long megs = num_physpages >> (20 - PAGE_SHIFT);
|
||||
|
||||
/* Use a smaller cluster for small-memory machines */
|
||||
if (megs < 16)
|
||||
page_cluster = 2;
|
||||
else
|
||||
page_cluster = 3;
|
||||
/*
|
||||
* Right now other parts of the system means that we
|
||||
* _really_ don't want to cluster much more
|
||||
*/
|
||||
hotcpu_notifier(cpu_swap_callback, 0);
|
||||
}
|
||||
Loading…
Reference in a new issue