diff options
Diffstat (limited to 'mm/page-writeback.c')
| -rw-r--r-- | mm/page-writeback.c | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 45e187b2d971..5daf5568b9e1 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -857,8 +857,11 @@ static void bdi_update_write_bandwidth(struct backing_dev_info *bdi, * bw * elapsed + write_bandwidth * (period - elapsed) * write_bandwidth = --------------------------------------------------- * period + * + * @written may have decreased due to account_page_redirty(). + * Avoid underflowing @bw calculation. */ - bw = written - bdi->written_stamp; + bw = written - min(written, bdi->written_stamp); bw *= HZ; if (unlikely(elapsed > period)) { do_div(bw, elapsed); @@ -922,7 +925,7 @@ static void global_update_bandwidth(unsigned long thresh, unsigned long now) { static DEFINE_SPINLOCK(dirty_lock); - static unsigned long update_time; + static unsigned long update_time = INITIAL_JIFFIES; /* * check locklessly first to optimize away locking for the most time @@ -2108,6 +2111,25 @@ void account_page_dirtied(struct page *page, struct address_space *mapping) EXPORT_SYMBOL(account_page_dirtied); /* + * Helper function for deaccounting dirty page without writeback. + * + * Doing this should *normally* only ever be done when a page + * is truncated, and is not actually mapped anywhere at all. However, + * fs/buffer.c does this when it notices that somebody has cleaned + * out all the buffers on a page without actually doing it through + * the VM. Can you say "ext3 is horribly ugly"? Thought you could. + */ +void account_page_cleaned(struct page *page, struct address_space *mapping) +{ + if (mapping_cap_account_dirty(mapping)) { + dec_zone_page_state(page, NR_FILE_DIRTY); + dec_bdi_stat(inode_to_bdi(mapping->host), BDI_RECLAIMABLE); + task_io_account_cancelled_write(PAGE_CACHE_SIZE); + } +} +EXPORT_SYMBOL(account_page_cleaned); + +/* * For address_spaces which do not use buffers. Just tag the page as dirty in * its radix tree. * @@ -2206,7 +2228,8 @@ int set_page_dirty(struct page *page) * it will confuse readahead and make it restart the size rampup * process. But it's a trivial problem. */ - ClearPageReclaim(page); + if (PageReclaim(page)) + ClearPageReclaim(page); #ifdef CONFIG_BLOCK if (!spd) spd = __set_page_dirty_buffers; |