Merge tag 'regulator-v3.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git...

[karo-tx-linux.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index a4317da60532be3eccb1c1e604362b3923271f65..518e2c3f4c75f0014a03817b4910cf4050a2f480 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -155,24 +155,6 @@ static unsigned long writeout_period_time = 0;
  */
 #define VM_COMPLETIONS_PERIOD_LEN (3*HZ)
 
-/*
- * Work out the current dirty-memory clamping and background writeout
- * thresholds.
- *
- * The main aim here is to lower them aggressively if there is a lot of mapped
- * memory around.  To avoid stressing page reclaim with lots of unreclaimable
- * pages.  It is better to clamp down on writers than to start swapping, and
- * performing lots of scanning.
- *
- * We only allow 1/2 of the currently-unmapped memory to be dirtied.
- *
- * We don't permit the clamping level to fall below 5% - that is getting rather
- * excessive.
- *
- * We make sure that the background writeout level is below the adjusted
- * clamping level.
- */
-
 /*
  * In a memory zone, there is a certain amount of pages we consider
  * available for the page cache, which is essentially the number of
@@ -1623,7 +1605,7 @@ void balance_dirty_pages_ratelimited(struct address_space *mapping)
         * 1000+ tasks, all of them start dirtying pages at exactly the same
         * time, hence all honoured too large initial task->nr_dirtied_pause.
         */
-       p =  &__get_cpu_var(bdp_ratelimits);
+       p =  this_cpu_ptr(&bdp_ratelimits);
        if (unlikely(current->nr_dirtied >= ratelimit))
                *p = 0;
        else if (unlikely(*p >= ratelimit_pages)) {
@@ -1635,7 +1617,7 @@ void balance_dirty_pages_ratelimited(struct address_space *mapping)
         * short-lived tasks (eg. gcc invocations in a kernel build) escaping
         * the dirty throttling and livelock other long-run dirtiers.
         */
-       p = &__get_cpu_var(dirty_throttle_leaks);
+       p = this_cpu_ptr(&dirty_throttle_leaks);
        if (*p > 0 && current->nr_dirtied < ratelimit) {
                unsigned long nr_pages_dirtied;
                nr_pages_dirtied = min(*p, ratelimit - current->nr_dirtied);
@@ -1682,7 +1664,7 @@ void throttle_vm_writeout(gfp_t gfp_mask)
 /*
  * sysctl handler for /proc/sys/vm/dirty_writeback_centisecs
  */
-int dirty_writeback_centisecs_handler(ctl_table *table, int write,
+int dirty_writeback_centisecs_handler(struct ctl_table *table, int write,
        void __user *buffer, size_t *length, loff_t *ppos)
 {
        proc_dointvec(table, write, buffer, length, ppos);
@@ -2398,7 +2380,7 @@ int test_clear_page_writeback(struct page *page)
        return ret;
 }
 
-int test_set_page_writeback(struct page *page)
+int __test_set_page_writeback(struct page *page, bool keep_write)
 {
        struct address_space *mapping = page_mapping(page);
        int ret;
@@ -2423,9 +2405,10 @@ int test_set_page_writeback(struct page *page)
                        radix_tree_tag_clear(&mapping->page_tree,
                                                page_index(page),
                                                PAGECACHE_TAG_DIRTY);
-               radix_tree_tag_clear(&mapping->page_tree,
-                                    page_index(page),
-                                    PAGECACHE_TAG_TOWRITE);
+               if (!keep_write)
+                       radix_tree_tag_clear(&mapping->page_tree,
+                                               page_index(page),
+                                               PAGECACHE_TAG_TOWRITE);
                spin_unlock_irqrestore(&mapping->tree_lock, flags);
        } else {
                ret = TestSetPageWriteback(page);
@@ -2436,7 +2419,7 @@ int test_set_page_writeback(struct page *page)
        return ret;
 
 }
-EXPORT_SYMBOL(test_set_page_writeback);
+EXPORT_SYMBOL(__test_set_page_writeback);
 
 /*
  * Return true if any of the pages in the mapping are marked with the