[PATCH] nfsiostat: Handle both readahead counts for statsver >= 1.2

[PATCH] nfsiostat: Handle both readahead counts for statsver >= 1.2

[Dave Wysochanski]

Later kernel versions convert NFS readpages to readahead so update
the counts accordingly.

Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
---
 tools/nfs-iostat/nfs-iostat.py | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/tools/nfs-iostat/nfs-iostat.py b/tools/nfs-iostat/nfs-iostat.py
index 1df74ba822b5..1ddd884faf58 100755
--- a/tools/nfs-iostat/nfs-iostat.py
+++ b/tools/nfs-iostat/nfs-iostat.py
@@ -43,7 +43,7 @@ NfsEventCounters = [
     'vfspermission',
     'vfsupdatepage',
     'vfsreadpage',
-    'vfsreadpages',
+    'vfsreadpages', # or vfsreadahead in statvers=1.2 or above
     'vfswritepage',
     'vfswritepages',
     'vfsreaddir',
@@ -86,7 +86,7 @@ class DeviceData:
             self.__nfs_data['export'] = words[1]
             self.__nfs_data['mountpoint'] = words[4]
             self.__nfs_data['fstype'] = words[7]
-            if words[7] == 'nfs':
+            if words[7] == 'nfs' or words[7] == 'nfs4':
                 self.__nfs_data['statvers'] = words[8]
         elif 'nfs' in words or 'nfs4' in words:
             self.__nfs_data['export'] = words[0]
@@ -294,8 +294,11 @@ class DeviceData:
         print()
         print('%d nfs_readpage() calls read %d pages' % \
             (vfsreadpage, vfsreadpage))
-        print('%d nfs_readpages() calls read %d pages' % \
-            (vfsreadpages, pages_read - vfsreadpage))
+        multipageread = "readpages"
+        if float(self.__nfs_data['statvers'].split('=',1)[1]) >= 1.2:
+            multipageread = "readahead"
+        print('%d nfs_%s() calls read %d pages' % \
+            (vfsreadpages, multipageread, pages_read - vfsreadpage))
         if vfsreadpages != 0:
             print('(%.1f pages per call)' % \
                 (float(pages_read - vfsreadpage) / vfsreadpages))
-- 
1.8.3.1