slab: introduce krealloc

[sfrench/cifs-2.6.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index be0efbde4994f5454198384ce274b62eb827adc4..a794945fd194dc11a0f522321c3b01e8aec57f52 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -67,12 +67,12 @@ static inline long sync_writeback_pages(void)
 /*
  * Start background writeback (via pdflush) at this percentage
  */
-int dirty_background_ratio = 10;
+int dirty_background_ratio = 5;
 
 /*
  * The generator of dirty data starts writeback at this percentage
  */
-int vm_dirty_ratio = 40;
+int vm_dirty_ratio = 10;
 
 /*
  * The interval between `kupdate'-style writebacks, in jiffies
@@ -296,11 +296,21 @@ void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
 }
 EXPORT_SYMBOL(balance_dirty_pages_ratelimited_nr);
 
-void throttle_vm_writeout(void)
+void throttle_vm_writeout(gfp_t gfp_mask)
 {
        long background_thresh;
        long dirty_thresh;
 
+       if ((gfp_mask & (__GFP_FS|__GFP_IO)) != (__GFP_FS|__GFP_IO)) {
+               /*
+                * The caller might hold locks which can prevent IO completion
+                * or progress in the filesystem.  So we cannot just sit here
+                * waiting for IO to complete.
+                */
+               congestion_wait(WRITE, HZ/10);
+               return;
+       }
+
         for ( ; ; ) {
                get_dirty_limits(&background_thresh, &dirty_thresh, NULL);
 
@@ -317,7 +327,6 @@ void throttle_vm_writeout(void)
         }
 }
 
-
 /*
  * writeback at least _min_pages, and keep writing until the amount of dirty
  * memory is less than the background threshold, or until we're all clean.
@@ -515,7 +524,7 @@ static int __cpuinit
 ratelimit_handler(struct notifier_block *self, unsigned long u, void *v)
 {
        writeback_set_ratelimit();
-       return 0;
+       return NOTIFY_DONE;
 }
 
 static struct notifier_block __cpuinitdata ratelimit_nb = {
@@ -549,9 +558,7 @@ void __init page_writeback_init(void)
 }
 
 /**
- * generic_writepages - walk the list of dirty pages of the given
- *                      address space and writepage() all of them.
- *
+ * generic_writepages - walk the list of dirty pages of the given address space and writepage() all of them.
  * @mapping: address space structure to write
  * @wbc: subtract the number of written pages from *@wbc->nr_to_write
  *
@@ -698,7 +705,6 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
 
 /**
  * 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
  *
@@ -736,6 +742,16 @@ int write_one_page(struct page *page, int wait)
 }
 EXPORT_SYMBOL(write_one_page);
 
+/*
+ * For address_spaces which do not use buffers nor write back.
+ */
+int __set_page_dirty_no_writeback(struct page *page)
+{
+       if (!PageDirty(page))
+               SetPageDirty(page);
+       return 0;
+}
+
 /*
  * For address_spaces which do not use buffers.  Just tag the page as dirty in
  * its radix tree.