static long ratelimit_pages = 32;
static long total_pages; /* The total number of pages in the machine. */
-static int dirty_exceeded; /* Dirty mem may be over limit */
+static int dirty_exceeded __cacheline_aligned_in_smp; /* Dirty mem may be over limit */
/*
* When balance_dirty_pages decides that the caller needs to perform some
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_centisecs = 5 * 100;
+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_centisecs = 30 * 100;
+int dirty_expire_interval = 30 * HZ;
/*
* Flag that makes the machine dump writes/reads and block dirtyings.
int block_dump;
/*
- * Flag that puts the machine in "laptop mode".
+ * Flag that puts the machine in "laptop mode". Doubles as a timeout in jiffies:
+ * a full sync is triggered after this time elapses without any disk activity.
*/
int laptop_mode;
if (nr_reclaimable + wbs.nr_writeback <= dirty_thresh)
break;
- dirty_exceeded = 1;
+ if (!dirty_exceeded)
+ dirty_exceeded = 1;
/* Note: nr_reclaimable denotes nr_dirty + nr_unstable.
* Unstable writes are a feature of certain networked
blk_congestion_wait(WRITE, HZ/10);
}
- if (nr_reclaimable + wbs.nr_writeback <= dirty_thresh)
+ if (nr_reclaimable + wbs.nr_writeback <= dirty_thresh && dirty_exceeded)
dirty_exceeded = 0;
if (writeback_in_progress(bdi))
}
/**
- * balance_dirty_pages_ratelimited - balance dirty memory state
- * @mapping - address_space which was dirtied
+ * 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);
+
+ /*
+ * Boost the allowable dirty threshold a bit for page
+ * allocators so they don't get DoS'ed by heavy writers
+ */
+ dirty_thresh += dirty_thresh / 10; /* wheeee... */
+
+ if (wbs.nr_unstable + wbs.nr_writeback <= dirty_thresh)
+ break;
+ blk_congestion_wait(WRITE, HZ/10);
+ }
+}
+
/*
* writeback at least _min_pages, and keep writing until the amount of dirty
* the whole world. Returns 0 if a pdflush thread was dispatched. Returns
* -1 if all pdflush threads were busy.
*/
-int wakeup_bdflush(long nr_pages)
+int wakeup_pdflush(long nr_pages)
{
if (nr_pages == 0) {
struct writeback_state wbs;
static void wb_timer_fn(unsigned long unused);
static void laptop_timer_fn(unsigned long unused);
-static struct timer_list wb_timer =
- TIMER_INITIALIZER(wb_timer_fn, 0, 0);
-static struct timer_list laptop_mode_wb_timer =
- TIMER_INITIALIZER(laptop_timer_fn, 0, 0);
+static DEFINE_TIMER(wb_timer, wb_timer_fn, 0, 0);
+static DEFINE_TIMER(laptop_mode_wb_timer, laptop_timer_fn, 0, 0);
/*
* Periodic writeback of "old" data.
* just walks the superblock inode list, writing back any inodes which are
* older than a specific point in time.
*
- * Try to run once per dirty_writeback_centisecs. But if a writeback event
- * takes longer than a dirty_writeback_centisecs interval, then leave a
+ * Try to run once per dirty_writeback_interval. But if a writeback event
+ * takes longer than a dirty_writeback_interval interval, then leave a
* one-second gap.
*
* older_than_this takes precedence over nr_to_write. So we'll only write back
sync_supers();
get_writeback_state(&wbs);
- oldest_jif = jiffies - (dirty_expire_centisecs * HZ) / 100;
+ oldest_jif = jiffies - dirty_expire_interval;
start_jif = jiffies;
- next_jif = start_jif + (dirty_writeback_centisecs * HZ) / 100;
+ next_jif = start_jif + dirty_writeback_interval;
nr_to_write = wbs.nr_dirty + wbs.nr_unstable +
(inodes_stat.nr_inodes - inodes_stat.nr_unused);
while (nr_to_write > 0) {
}
if (time_before(next_jif, jiffies + HZ))
next_jif = jiffies + HZ;
- if (dirty_writeback_centisecs)
+ if (dirty_writeback_interval)
mod_timer(&wb_timer, next_jif);
}
int dirty_writeback_centisecs_handler(ctl_table *table, int write,
struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
{
- proc_dointvec(table, write, file, buffer, length, ppos);
- if (dirty_writeback_centisecs) {
+ proc_dointvec_userhz_jiffies(table, write, file, buffer, length, ppos);
+ if (dirty_writeback_interval) {
mod_timer(&wb_timer,
- jiffies + (dirty_writeback_centisecs * HZ) / 100);
- } else {
+ jiffies + dirty_writeback_interval);
+ } else {
del_timer(&wb_timer);
}
return 0;
*/
void laptop_io_completion(void)
{
- mod_timer(&laptop_mode_wb_timer, jiffies + laptop_mode * HZ);
+ mod_timer(&laptop_mode_wb_timer, jiffies + laptop_mode);
}
/*
if (vm_dirty_ratio <= 0)
vm_dirty_ratio = 1;
}
- mod_timer(&wb_timer, jiffies + (dirty_writeback_centisecs * HZ) / 100);
+ mod_timer(&wb_timer, jiffies + dirty_writeback_interval);
set_ratelimit();
register_cpu_notifier(&ratelimit_nb);
}
int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
{
+ int ret;
+
if (wbc->nr_to_write <= 0)
return 0;
+ wbc->for_writepages = 1;
if (mapping->a_ops->writepages)
- return mapping->a_ops->writepages(mapping, wbc);
- return generic_writepages(mapping, wbc);
+ ret = mapping->a_ops->writepages(mapping, wbc);
+ else
+ ret = generic_writepages(mapping, wbc);
+ wbc->for_writepages = 0;
+ return ret;
}
/**
* write_one_page - write out a single page and optionally wait on I/O
*
- * @page - the page to write
- * @wait - if true, wait on writeout
+ * @page: the page to write
+ * @wait: if true, wait on writeout
*
* The page must be locked by the caller and will be unlocked upon return.
*
*/
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 (mapping) {
- spin_lock_irq(&mapping->tree_lock);
+ write_lock_irq(&mapping->tree_lock);
mapping2 = page_mapping(page);
if (mapping2) { /* Race with truncate? */
BUG_ON(mapping2 != mapping);
- if (!mapping->backing_dev_info->memory_backed)
+ if (mapping_cap_account_dirty(mapping))
inc_page_state(nr_dirty);
radix_tree_tag_set(&mapping->page_tree,
page_index(page), PAGECACHE_TAG_DIRTY);
}
- spin_unlock_irq(&mapping->tree_lock);
+ write_unlock_irq(&mapping->tree_lock);
if (mapping->host) {
/* !PageAnon && !swapper_space */
__mark_inode_dirty(mapping->host,
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);
unsigned long flags;
if (mapping) {
- spin_lock_irqsave(&mapping->tree_lock, flags);
+ write_lock_irqsave(&mapping->tree_lock, flags);
if (TestClearPageDirty(page)) {
radix_tree_tag_clear(&mapping->page_tree,
page_index(page),
PAGECACHE_TAG_DIRTY);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
- if (!mapping->backing_dev_info->memory_backed)
+ write_unlock_irqrestore(&mapping->tree_lock, flags);
+ if (mapping_cap_account_dirty(mapping))
dec_page_state(nr_dirty);
return 1;
}
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ write_unlock_irqrestore(&mapping->tree_lock, flags);
return 0;
}
return TestClearPageDirty(page);
if (mapping) {
if (TestClearPageDirty(page)) {
- if (!mapping->backing_dev_info->memory_backed)
+ if (mapping_cap_account_dirty(mapping))
dec_page_state(nr_dirty);
return 1;
}
}
EXPORT_SYMBOL(clear_page_dirty_for_io);
-/*
- * Clear a page's dirty flag while ignoring dirty memory accounting
- */
-int __clear_page_dirty(struct page *page)
-{
- struct address_space *mapping = page_mapping(page);
-
- if (mapping) {
- unsigned long flags;
-
- spin_lock_irqsave(&mapping->tree_lock, flags);
- if (TestClearPageDirty(page)) {
- radix_tree_tag_clear(&mapping->page_tree,
- page_index(page),
- PAGECACHE_TAG_DIRTY);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
- return 1;
- }
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
- return 0;
- }
- return TestClearPageDirty(page);
-}
-
int test_clear_page_writeback(struct page *page)
{
struct address_space *mapping = page_mapping(page);
if (mapping) {
unsigned long flags;
- spin_lock_irqsave(&mapping->tree_lock, flags);
+ write_lock_irqsave(&mapping->tree_lock, flags);
ret = TestClearPageWriteback(page);
if (ret)
radix_tree_tag_clear(&mapping->page_tree,
page_index(page),
PAGECACHE_TAG_WRITEBACK);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ write_unlock_irqrestore(&mapping->tree_lock, flags);
} else {
ret = TestClearPageWriteback(page);
}
if (mapping) {
unsigned long flags;
- spin_lock_irqsave(&mapping->tree_lock, flags);
+ write_lock_irqsave(&mapping->tree_lock, flags);
ret = TestSetPageWriteback(page);
if (!ret)
radix_tree_tag_set(&mapping->page_tree,
radix_tree_tag_clear(&mapping->page_tree,
page_index(page),
PAGECACHE_TAG_DIRTY);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ write_unlock_irqrestore(&mapping->tree_lock, flags);
} else {
ret = TestSetPageWriteback(page);
}
unsigned long flags;
int ret;
- spin_lock_irqsave(&mapping->tree_lock, flags);
+ read_lock_irqsave(&mapping->tree_lock, flags);
ret = radix_tree_tagged(&mapping->page_tree, tag);
- spin_unlock_irqrestore(&mapping->tree_lock, flags);
+ read_unlock_irqrestore(&mapping->tree_lock, flags);
return ret;
}
EXPORT_SYMBOL(mapping_tagged);
git://git.onelab.eu / linux-2.6.git / blobdiff