#include <linux/backing-dev.h>
#include <linux/blkdev.h>
#include <linux/mpage.h>
+#include <linux/rmap.h>
#include <linux/percpu.h>
#include <linux/notifier.h>
#include <linux/smp.h>
int vm_dirty_ratio = 40;
/*
- * The interval between `kupdate'-style writebacks, in centiseconds
- * (hundredths of a second)
+ * The interval between `kupdate'-style writebacks, in jiffies
*/
int dirty_writeback_interval = 5 * HZ;
/*
- * The longest number of centiseconds for which data is allowed to remain dirty
+ * The longest number of jiffies for which data is allowed to remain dirty
*/
int dirty_expire_interval = 30 * HZ;
static void background_writeout(unsigned long _min_pages);
-struct writeback_state
-{
- unsigned long nr_dirty;
- unsigned long nr_unstable;
- unsigned long nr_mapped;
- unsigned long nr_writeback;
-};
-
-static void get_writeback_state(struct writeback_state *wbs)
-{
- wbs->nr_dirty = read_page_state(nr_dirty);
- wbs->nr_unstable = read_page_state(nr_unstable);
- wbs->nr_mapped = read_page_state(nr_mapped);
- wbs->nr_writeback = read_page_state(nr_writeback);
-}
-
/*
* Work out the current dirty-memory clamping and background writeout
* thresholds.
* clamping level.
*/
static void
-get_dirty_limits(struct writeback_state *wbs, long *pbackground, long *pdirty,
- struct address_space *mapping)
+get_dirty_limits(long *pbackground, long *pdirty,
+ struct address_space *mapping)
{
int background_ratio; /* Percentages */
int dirty_ratio;
unsigned long available_memory = total_pages;
struct task_struct *tsk;
- get_writeback_state(wbs);
-
#ifdef CONFIG_HIGHMEM
/*
* If this mapping can only allocate from low memory,
#endif
- unmapped_ratio = 100 - (wbs->nr_mapped * 100) / total_pages;
+ unmapped_ratio = 100 - ((global_page_state(NR_FILE_MAPPED) +
+ global_page_state(NR_ANON_PAGES)) * 100) /
+ total_pages;
dirty_ratio = vm_dirty_ratio;
if (dirty_ratio > unmapped_ratio / 2)
*/
static void balance_dirty_pages(struct address_space *mapping)
{
- struct writeback_state wbs;
long nr_reclaimable;
long background_thresh;
long dirty_thresh;
.sync_mode = WB_SYNC_NONE,
.older_than_this = NULL,
.nr_to_write = write_chunk,
+ .range_cyclic = 1,
};
- get_dirty_limits(&wbs, &background_thresh,
- &dirty_thresh, mapping);
- nr_reclaimable = wbs.nr_dirty + wbs.nr_unstable;
- if (nr_reclaimable + wbs.nr_writeback <= dirty_thresh)
- break;
+ get_dirty_limits(&background_thresh, &dirty_thresh, mapping);
+ nr_reclaimable = global_page_state(NR_FILE_DIRTY) +
+ global_page_state(NR_UNSTABLE_NFS);
+ if (nr_reclaimable + global_page_state(NR_WRITEBACK) <=
+ dirty_thresh)
+ break;
if (!dirty_exceeded)
dirty_exceeded = 1;
*/
if (nr_reclaimable) {
writeback_inodes(&wbc);
- get_dirty_limits(&wbs, &background_thresh,
- &dirty_thresh, mapping);
- nr_reclaimable = wbs.nr_dirty + wbs.nr_unstable;
- if (nr_reclaimable + wbs.nr_writeback <= dirty_thresh)
- break;
+ get_dirty_limits(&background_thresh,
+ &dirty_thresh, mapping);
+ nr_reclaimable = global_page_state(NR_FILE_DIRTY) +
+ global_page_state(NR_UNSTABLE_NFS);
+ if (nr_reclaimable +
+ global_page_state(NR_WRITEBACK)
+ <= dirty_thresh)
+ break;
pages_written += write_chunk - wbc.nr_to_write;
if (pages_written >= write_chunk)
break; /* We've done our duty */
blk_congestion_wait(WRITE, HZ/10);
}
- if (nr_reclaimable + wbs.nr_writeback <= dirty_thresh && dirty_exceeded)
- dirty_exceeded = 0;
+ if (nr_reclaimable + global_page_state(NR_WRITEBACK)
+ <= dirty_thresh && dirty_exceeded)
+ dirty_exceeded = 0;
if (writeback_in_progress(bdi))
return; /* pdflush is already working this queue */
pdflush_operation(background_writeout, 0);
}
+void set_page_dirty_balance(struct page *page)
+{
+ if (set_page_dirty(page)) {
+ struct address_space *mapping = page_mapping(page);
+
+ if (mapping)
+ balance_dirty_pages_ratelimited(mapping);
+ }
+}
+
/**
- * balance_dirty_pages_ratelimited - balance dirty memory state
+ * balance_dirty_pages_ratelimited_nr - balance dirty memory state
* @mapping: address_space which was dirtied
+ * @nr_pages_dirtied: number of pages which the caller has just dirtied
*
* Processes which are dirtying memory should call in here once for each page
* which was newly dirtied. The function will periodically check the system's
* limit we decrease the ratelimiting by a lot, to prevent individual processes
* from overshooting the limit by (ratelimit_pages) each.
*/
-void balance_dirty_pages_ratelimited(struct address_space *mapping)
+void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
+ unsigned long nr_pages_dirtied)
{
- static DEFINE_PER_CPU(int, ratelimits) = 0;
- long ratelimit;
+ static DEFINE_PER_CPU(unsigned long, ratelimits) = 0;
+ unsigned long ratelimit;
+ unsigned long *p;
ratelimit = ratelimit_pages;
if (dirty_exceeded)
* Check the rate limiting. Also, we do not want to throttle real-time
* tasks in balance_dirty_pages(). Period.
*/
- if (get_cpu_var(ratelimits)++ >= ratelimit) {
- __get_cpu_var(ratelimits) = 0;
- put_cpu_var(ratelimits);
+ preempt_disable();
+ p = &__get_cpu_var(ratelimits);
+ *p += nr_pages_dirtied;
+ if (unlikely(*p >= ratelimit)) {
+ *p = 0;
+ preempt_enable();
balance_dirty_pages(mapping);
return;
}
- put_cpu_var(ratelimits);
+ preempt_enable();
}
-EXPORT_SYMBOL(balance_dirty_pages_ratelimited);
+EXPORT_SYMBOL(balance_dirty_pages_ratelimited_nr);
void throttle_vm_writeout(void)
{
- struct writeback_state wbs;
long background_thresh;
long dirty_thresh;
for ( ; ; ) {
- get_dirty_limits(&wbs, &background_thresh, &dirty_thresh, NULL);
+ get_dirty_limits(&background_thresh, &dirty_thresh, NULL);
/*
* Boost the allowable dirty threshold a bit for page
*/
dirty_thresh += dirty_thresh / 10; /* wheeee... */
- if (wbs.nr_unstable + wbs.nr_writeback <= dirty_thresh)
- break;
+ if (global_page_state(NR_UNSTABLE_NFS) +
+ global_page_state(NR_WRITEBACK) <= dirty_thresh)
+ break;
blk_congestion_wait(WRITE, HZ/10);
}
}
.older_than_this = NULL,
.nr_to_write = 0,
.nonblocking = 1,
+ .range_cyclic = 1,
};
for ( ; ; ) {
- struct writeback_state wbs;
long background_thresh;
long dirty_thresh;
- get_dirty_limits(&wbs, &background_thresh, &dirty_thresh, NULL);
- if (wbs.nr_dirty + wbs.nr_unstable < background_thresh
+ get_dirty_limits(&background_thresh, &dirty_thresh, NULL);
+ if (global_page_state(NR_FILE_DIRTY) +
+ global_page_state(NR_UNSTABLE_NFS) < background_thresh
&& min_pages <= 0)
break;
wbc.encountered_congestion = 0;
*/
int wakeup_pdflush(long nr_pages)
{
- if (nr_pages == 0) {
- struct writeback_state wbs;
-
- get_writeback_state(&wbs);
- nr_pages = wbs.nr_dirty + wbs.nr_unstable;
- }
+ if (nr_pages == 0)
+ nr_pages = global_page_state(NR_FILE_DIRTY) +
+ global_page_state(NR_UNSTABLE_NFS);
return pdflush_operation(background_writeout, nr_pages);
}
unsigned long start_jif;
unsigned long next_jif;
long nr_to_write;
- struct writeback_state wbs;
struct writeback_control wbc = {
.bdi = NULL,
.sync_mode = WB_SYNC_NONE,
.nr_to_write = 0,
.nonblocking = 1,
.for_kupdate = 1,
+ .range_cyclic = 1,
};
sync_supers();
- get_writeback_state(&wbs);
oldest_jif = jiffies - dirty_expire_interval;
start_jif = jiffies;
next_jif = start_jif + dirty_writeback_interval;
- nr_to_write = wbs.nr_dirty + wbs.nr_unstable +
+ nr_to_write = global_page_state(NR_FILE_DIRTY) +
+ global_page_state(NR_UNSTABLE_NFS) +
(inodes_stat.nr_inodes - inodes_stat.nr_unused);
while (nr_to_write > 0) {
wbc.encountered_congestion = 0;
ratelimit_pages = (4096 * 1024) / PAGE_CACHE_SIZE;
}
-static int
+static int __cpuinit
ratelimit_handler(struct notifier_block *self, unsigned long u, void *v)
{
set_ratelimit();
return 0;
}
-static struct notifier_block ratelimit_nb = {
+static struct notifier_block __cpuinitdata ratelimit_nb = {
.notifier_call = ratelimit_handler,
.next = NULL,
};
return 0;
wbc->for_writepages = 1;
if (mapping->a_ops->writepages)
- ret = mapping->a_ops->writepages(mapping, wbc);
+ ret = mapping->a_ops->writepages(mapping, wbc);
else
ret = generic_writepages(mapping, wbc);
wbc->for_writepages = 0;
*/
int __set_page_dirty_nobuffers(struct page *page)
{
- int ret = 0;
-
if (!TestSetPageDirty(page)) {
struct address_space *mapping = page_mapping(page);
struct address_space *mapping2;
if (mapping2) { /* Race with truncate? */
BUG_ON(mapping2 != mapping);
if (mapping_cap_account_dirty(mapping))
- inc_page_state(nr_dirty);
+ __inc_zone_page_state(page,
+ NR_FILE_DIRTY);
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
I_DIRTY_PAGES);
}
}
+ return 1;
}
- return ret;
+ return 0;
}
EXPORT_SYMBOL(__set_page_dirty_nobuffers);
return (*spd)(page);
return __set_page_dirty_buffers(page);
}
- if (!PageDirty(page))
- SetPageDirty(page);
+ if (!PageDirty(page)) {
+ if (!TestSetPageDirty(page))
+ return 1;
+ }
return 0;
}
EXPORT_SYMBOL(set_page_dirty);
{
int ret;
- lock_page(page);
+ lock_page_nosync(page);
ret = set_page_dirty(page);
unlock_page(page);
return ret;
page_index(page),
PAGECACHE_TAG_DIRTY);
write_unlock_irqrestore(&mapping->tree_lock, flags);
- if (mapping_cap_account_dirty(mapping))
- dec_page_state(nr_dirty);
+ /*
+ * We can continue to use `mapping' here because the
+ * page is locked, which pins the address_space
+ */
+ if (mapping_cap_account_dirty(mapping)) {
+ page_mkclean(page);
+ dec_zone_page_state(page, NR_FILE_DIRTY);
+ }
return 1;
}
write_unlock_irqrestore(&mapping->tree_lock, flags);
if (mapping) {
if (TestClearPageDirty(page)) {
- if (mapping_cap_account_dirty(mapping))
- dec_page_state(nr_dirty);
+ if (mapping_cap_account_dirty(mapping)) {
+ page_mkclean(page);
+ dec_zone_page_state(page, NR_FILE_DIRTY);
+ }
return 1;
}
return 0;
EXPORT_SYMBOL(test_set_page_writeback);
/*
+ * Wakes up tasks that are being throttled due to writeback congestion
+ */
+void writeback_congestion_end(void)
+{
+ blk_congestion_end(WRITE);
+}
+EXPORT_SYMBOL(writeback_congestion_end);
+
+/*
* Return true if any of the pages in the mapping are marged with the
* passed tag.
*/
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff