NFS: add I/O performance counters
Invoke the byte and event counter macros where we want to count bytes and
events.
Clean-up: fix a possible NULL dereference in nfs_lock, and simplify
nfs_file_open.
Test-plan:
fsx and iozone on UP and SMP systems, with and without pre-emption. Watch
for memory overwrite bugs, and performance loss (significantly more CPU
required per op).
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index 05eb43f..ae3ddd2 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -31,6 +31,8 @@
#include <asm/system.h>
+#include "iostat.h"
+
#define NFSDBG_FACILITY NFSDBG_PAGECACHE
static int nfs_pagein_one(struct list_head *, struct inode *);
@@ -133,6 +135,8 @@
}
count -= result;
rdata->args.pgbase += result;
+ nfs_add_stats(inode, NFSIOS_SERVERREADBYTES, result);
+
/* Note: result == 0 should only happen if we're caching
* a write that extends the file and punches a hole.
*/
@@ -458,8 +462,11 @@
dprintk("NFS: %4d nfs_readpage_result, (status %d)\n",
task->tk_pid, status);
+ nfs_add_stats(data->inode, NFSIOS_SERVERREADBYTES, resp->count);
+
/* Is this a short read? */
if (task->tk_status >= 0 && resp->count < argp->count && !resp->eof) {
+ nfs_inc_stats(data->inode, NFSIOS_SHORTREAD);
/* Has the server at least made some progress? */
if (resp->count != 0) {
/* Yes, so retry the read at the end of the data */
@@ -491,6 +498,9 @@
dprintk("NFS: nfs_readpage (%p %ld@%lu)\n",
page, PAGE_CACHE_SIZE, page->index);
+ nfs_inc_stats(inode, NFSIOS_VFSREADPAGE);
+ nfs_add_stats(inode, NFSIOS_READPAGES, 1);
+
/*
* Try to flush any pending writes to the file..
*
@@ -570,6 +580,7 @@
inode->i_sb->s_id,
(long long)NFS_FILEID(inode),
nr_pages);
+ nfs_inc_stats(inode, NFSIOS_VFSREADPAGES);
if (filp == NULL) {
desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ);
@@ -582,6 +593,7 @@
if (!list_empty(&head)) {
int err = nfs_pagein_list(&head, server->rpages);
if (!ret)
+ nfs_add_stats(inode, NFSIOS_READPAGES, err);
ret = err;
}
put_nfs_open_context(desc.ctx);
