x86, espfix: Make espfix64 a Kconfig option, fix UML

[pandora-kernel.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 50f0824..d2ac057 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -559,7 +559,7 @@ static unsigned long bdi_position_ratio(struct backing_dev_info *bdi,
         *     => fast response on large errors; small oscillation near setpoint
         */
        setpoint = (freerun + limit) / 2;
-       x = div_s64((setpoint - dirty) << RATELIMIT_CALC_SHIFT,
+       x = div64_s64(((s64)setpoint - (s64)dirty) << RATELIMIT_CALC_SHIFT,
                    limit - setpoint + 1);
        pos_ratio = x;
        pos_ratio = pos_ratio * x >> RATELIMIT_CALC_SHIFT;
@@ -625,7 +625,7 @@ static unsigned long bdi_position_ratio(struct backing_dev_info *bdi,
        x_intercept = bdi_setpoint + span;
 
        if (bdi_dirty < x_intercept - span / 4) {
-               pos_ratio = div_u64(pos_ratio * (x_intercept - bdi_dirty),
+               pos_ratio = div64_u64(pos_ratio * (x_intercept - bdi_dirty),
                                    x_intercept - bdi_setpoint + 1);
        } else
                pos_ratio /= 4;
@@ -1776,11 +1776,12 @@ int __set_page_dirty_nobuffers(struct page *page)
        if (!TestSetPageDirty(page)) {
                struct address_space *mapping = page_mapping(page);
                struct address_space *mapping2;
+               unsigned long flags;
 
                if (!mapping)
                        return 1;
 
-               spin_lock_irq(&mapping->tree_lock);
+               spin_lock_irqsave(&mapping->tree_lock, flags);
                mapping2 = page_mapping(page);
                if (mapping2) { /* Race with truncate? */
                        BUG_ON(mapping2 != mapping);
@@ -1789,7 +1790,7 @@ int __set_page_dirty_nobuffers(struct page *page)
                        radix_tree_tag_set(&mapping->page_tree,
                                page_index(page), PAGECACHE_TAG_DIRTY);
                }
-               spin_unlock_irq(&mapping->tree_lock);
+               spin_unlock_irqrestore(&mapping->tree_lock, flags);
                if (mapping->host) {
                        /* !PageAnon && !swapper_space */
                        __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
@@ -1800,6 +1801,24 @@ int __set_page_dirty_nobuffers(struct page *page)
 }
 EXPORT_SYMBOL(__set_page_dirty_nobuffers);
 
+/*
+ * Call this whenever redirtying a page, to de-account the dirty counters
+ * (NR_DIRTIED, BDI_DIRTIED, tsk->nr_dirtied), so that they match the written
+ * counters (NR_WRITTEN, BDI_WRITTEN) in long term. The mismatches will lead to
+ * systematic errors in balanced_dirty_ratelimit and the dirty pages position
+ * control.
+ */
+void account_page_redirty(struct page *page)
+{
+       struct address_space *mapping = page->mapping;
+       if (mapping && mapping_cap_account_dirty(mapping)) {
+               current->nr_dirtied--;
+               dec_zone_page_state(page, NR_DIRTIED);
+               dec_bdi_stat(mapping->backing_dev_info, BDI_DIRTIED);
+       }
+}
+EXPORT_SYMBOL(account_page_redirty);
+
 /*
  * When a writepage implementation decides that it doesn't want to write this
  * page for some reason, it should redirty the locked page via
@@ -1808,6 +1827,7 @@ EXPORT_SYMBOL(__set_page_dirty_nobuffers);
 int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
 {
        wbc->pages_skipped++;
+       account_page_redirty(page);
        return __set_page_dirty_nobuffers(page);
 }
 EXPORT_SYMBOL(redirty_page_for_writepage);