[nfs-utils PATCH 8/8] mountstats/nfsiostat: merge and rework the infinite and counted loops

[Frank Sorenson <sorenson@redhat.com>]

We always want to print at least once, so move the first print
before the interval/count tests.

The infinite loop and counted loop are nearly identical, so
we merge them, and break out of the loop if necessary.

By decrementing the count and checking at the beginning of the
loop, we also fix a bug where we sleep and parse the mountstats
file one extra time after count iterations.

Signed-off-by: Frank Sorenson <sorenson@redhat.com>
---
 tools/mountstats/mountstats.py | 40 ++++++++++++++--------------------
 tools/nfs-iostat/nfs-iostat.py | 40 ++++++++++++++--------------------
 2 files changed, 32 insertions(+), 48 deletions(-)

diff --git a/tools/mountstats/mountstats.py b/tools/mountstats/mountstats.py
index fbd57f51..d488f9e1 100755
--- a/tools/mountstats/mountstats.py
+++ b/tools/mountstats/mountstats.py
@@ -1007,37 +1007,29 @@ def iostat_command(args):
     else:
         old_mountstats = None
 
+    sample_time = 0
+
     # make certain devices contains only NFS mount points
     devices = list_nfs_mounts(origdevices, mountstats)
-
-    sample_time = 0
+    print_iostat_summary(old_mountstats, mountstats, devices, sample_time)
 
     if args.interval is None:
-        print_iostat_summary(old_mountstats, mountstats, devices, sample_time)
         return
 
-    if args.count is not None:
-        count = args.count
-        while count != 0:
-            print_iostat_summary(old_mountstats, mountstats, devices, sample_time)
-            old_mountstats = mountstats
-            time.sleep(args.interval)
-            sample_time = args.interval
-            mountstats = parse_stats_file(args.infile)
-            # nfs mountpoints may appear or disappear, so we need to
-            # recheck the devices list each time we parse mountstats
-            devices = list_nfs_mounts(origdevices, mountstats)
+    count = args.count
+    while True:
+        if count is not None:
             count -= 1
-    else: 
-        while True:
-            print_iostat_summary(old_mountstats, mountstats, devices, sample_time)
-            old_mountstats = mountstats
-            time.sleep(args.interval)
-            sample_time = args.interval
-            mountstats = parse_stats_file(args.infile)
-            # nfs mountpoints may appear or disappear, so we need to
-            # recheck the devices list each time we parse mountstats
-            devices = list_nfs_mounts(origdevices, mountstats)
+            if count == 0:
+                break
+        time.sleep(args.interval)
+        old_mountstats = mountstats
+        sample_time = args.interval
+        mountstats = parse_stats_file(args.infile)
+        # nfs mountpoints may appear or disappear, so we need to
+        # recheck the devices list each time we parse mountstats
+        devices = list_nfs_mounts(origdevices, mountstats)
+        print_iostat_summary(old_mountstats, mountstats, devices, sample_time)
 
     args.infile.close()
     if args.since:
diff --git a/tools/nfs-iostat/nfs-iostat.py b/tools/nfs-iostat/nfs-iostat.py
index f69ffb0e..e46b1a83 100755
--- a/tools/nfs-iostat/nfs-iostat.py
+++ b/tools/nfs-iostat/nfs-iostat.py
@@ -614,37 +614,29 @@ client are listed.
                 print('Illegal <count> value %s' % arg)
                 return
 
-    # make certain devices contains only NFS mount points
-    devices = list_nfs_mounts(origdevices, mountstats)
-
     old_mountstats = None
     sample_time = 0.0
 
+    # make certain devices contains only NFS mount points
+    devices = list_nfs_mounts(origdevices, mountstats)
+    print_iostat_summary(old_mountstats, mountstats, devices, sample_time, options)
+
     if not interval_seen:
-        print_iostat_summary(old_mountstats, mountstats, devices, sample_time, options)
         return
 
-    if count_seen:
-        while count != 0:
-            print_iostat_summary(old_mountstats, mountstats, devices, sample_time, options)
-            old_mountstats = mountstats
-            time.sleep(interval)
-            sample_time = interval
-            mountstats = parse_stats_file('/proc/self/mountstats')
-            # nfs mountpoints may appear or disappear, so we need to
-            # recheck the devices list each time we parse mountstats
-            devices = list_nfs_mounts(origdevices,mountstats)
+    while True:
+        if count_seen:
             count -= 1
-    else: 
-        while True:
-            print_iostat_summary(old_mountstats, mountstats, devices, sample_time, options)
-            old_mountstats = mountstats
-            time.sleep(interval)
-            sample_time = interval
-            mountstats = parse_stats_file('/proc/self/mountstats')
-            # nfs mountpoints may appear or disappear, so we need to
-            # recheck the devices list each time we parse mountstats
-            devices = list_nfs_mounts(origdevices,mountstats)
+            if count == 0:
+                break
+        time.sleep(interval)
+        old_mountstats = mountstats
+        sample_time = interval
+        mountstats = parse_stats_file('/proc/self/mountstats')
+        # nfs mountpoints may appear or disappear, so we need to
+        # recheck the devices list each time we parse mountstats
+        devices = list_nfs_mounts(origdevices, mountstats)
+        print_iostat_summary(old_mountstats, mountstats, devices, sample_time, options)
 
 #
 # Main
-- 
2.48.1