[PATCH] Fix vmi time header bug

[powerpc.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index f7e088f..f469e3c 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -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.