NFS: Fix up writeback_control->nr_to_write accounting

We're really accounting for the same page twice now: once in
generic_writepages(), and once in nfs_scan_dirty().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 47ae2b4..bc9fab6 100644 (file)
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -288,11 +288,10 @@ long nfs_scan_dirty(struct address_space *mapping,
        struct nfs_page *pgvec[NFS_SCAN_MAXENTRIES];
        struct nfs_page *req;
        pgoff_t idx_start, idx_end;
-       long count = wbc->nr_to_write;
        long res = 0;
        int found, i;
 
-       if (nfsi->ndirty == 0 || count <= 0)
+       if (nfsi->ndirty == 0)
                return 0;
        if (wbc->range_cyclic) {
                idx_start = 0;
@@ -308,8 +307,6 @@ long nfs_scan_dirty(struct address_space *mapping,
        for (;;) {
                unsigned int toscan = NFS_SCAN_MAXENTRIES;
 
-               if (toscan > count)
-                       toscan = count;
                found = radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree,
                                (void **)&pgvec[0], idx_start, toscan,
                                NFS_PAGE_TAG_DIRTY);
@@ -334,16 +331,11 @@ long nfs_scan_dirty(struct address_space *mapping,
                        res++;
                        if (res == LONG_MAX)
                                goto out;
-                       count--;
-                       if (count == 0)
-                               goto out;
-
 next:
                        idx_start = req->wb_index + 1;
                }
        }
 out:
-       wbc->nr_to_write = count;
        WARN_ON ((nfsi->ndirty == 0) != list_empty(&nfsi->dirty));
        return res;
 }