NFS: Fix up page writeback accounting
Currently, we are crediting all the calls to nfs_writepages_callback()
(i.e. the nfs_writepages() callback) to nfs_writepage(). Aside from
being inconsistent with the behaviour of the equivalent readpage/readpages
accounting, this also means that we cannot distinguish between bulk writes
and single page writebacks (which confuses the 'nfsiostat -p' tool).
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 72624dc..cfa4776 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -569,19 +569,17 @@
if (!nfs_pageio_add_request(pgio, req)) {
nfs_redirty_request(req);
ret = pgio->pg_error;
- }
+ } else
+ nfs_add_stats(page_file_mapping(page)->host,
+ NFSIOS_WRITEPAGES, 1);
out:
return ret;
}
static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio)
{
- struct inode *inode = page_file_mapping(page)->host;
int ret;
- nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
- nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1);
-
nfs_pageio_cond_complete(pgio, page_file_index(page));
ret = nfs_page_async_flush(pgio, page, wbc->sync_mode == WB_SYNC_NONE);
if (ret == -EAGAIN) {
@@ -597,9 +595,11 @@
static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc)
{
struct nfs_pageio_descriptor pgio;
+ struct inode *inode = page_file_mapping(page)->host;
int err;
- nfs_pageio_init_write(&pgio, page->mapping->host, wb_priority(wbc),
+ nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
+ nfs_pageio_init_write(&pgio, inode, wb_priority(wbc),
false, &nfs_async_write_completion_ops);
err = nfs_do_writepage(page, wbc, &pgio);
nfs_pageio_complete(&pgio);