kbuild: fix first module build

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

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 4073d531cd7b6ad8486330f02edcea9a16e9d5e7..7845462064f4c13457528852c09e5db9e770596b 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -37,7 +37,7 @@
 
 /*
  * The maximum number of pages to writeout in a single bdflush/kupdate
- * operation.  We do this so we don't hold I_LOCK against an inode for
+ * operation.  We do this so we don't hold I_SYNC against an inode for
  * enormous amounts of time, which would block a userspace task which has
  * been forced to throttle against that inode.  Also, the code reevaluates
  * the dirty each time it has written this many pages.
@@ -502,16 +502,6 @@ 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, NULL);
 
@@ -525,6 +515,14 @@ void throttle_vm_writeout(gfp_t gfp_mask)
                        global_page_state(NR_WRITEBACK) <= dirty_thresh)
                                break;
                 congestion_wait(WRITE, HZ/10);
+
+               /*
+                * 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.
+                */
+               if ((gfp_mask & (__GFP_FS|__GFP_IO)) != (__GFP_FS|__GFP_IO))
+                       break;
         }
 }
 
@@ -553,6 +551,7 @@ static void background_writeout(unsigned long _min_pages)
                        global_page_state(NR_UNSTABLE_NFS) < background_thresh
                                && min_pages <= 0)
                        break;
+               wbc.more_io = 0;
                wbc.encountered_congestion = 0;
                wbc.nr_to_write = MAX_WRITEBACK_PAGES;
                wbc.pages_skipped = 0;
@@ -560,8 +559,9 @@ static void background_writeout(unsigned long _min_pages)
                min_pages -= MAX_WRITEBACK_PAGES - wbc.nr_to_write;
                if (wbc.nr_to_write > 0 || wbc.pages_skipped > 0) {
                        /* Wrote less than expected */
-                       congestion_wait(WRITE, HZ/10);
-                       if (!wbc.encountered_congestion)
+                       if (wbc.encountered_congestion || wbc.more_io)
+                               congestion_wait(WRITE, HZ/10);
+                       else
                                break;
                }
        }
@@ -626,11 +626,12 @@ static void wb_kupdate(unsigned long arg)
                        global_page_state(NR_UNSTABLE_NFS) +
                        (inodes_stat.nr_inodes - inodes_stat.nr_unused);
        while (nr_to_write > 0) {
+               wbc.more_io = 0;
                wbc.encountered_congestion = 0;
                wbc.nr_to_write = MAX_WRITEBACK_PAGES;
                writeback_inodes(&wbc);
                if (wbc.nr_to_write > 0) {
-                       if (wbc.encountered_congestion)
+                       if (wbc.encountered_congestion || wbc.more_io)
                                congestion_wait(WRITE, HZ/10);
                        else
                                break;  /* All the old data is written */
@@ -849,8 +850,10 @@ retry:
 
                        ret = (*writepage)(page, wbc, data);
 
-                       if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE))
+                       if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) {
                                unlock_page(page);
+                               ret = 0;
+                       }
                        if (ret || (--(wbc->nr_to_write) <= 0))
                                done = 1;
                        if (wbc->nonblocking && bdi_write_congested(bdi)) {