[Testfix] Fix I/O logic to use distinct file names

Problem:
Testcases test_mount_snap_delete and test_restore_online_vol
were failing in the latest runs with the below traceback
```
Traceback (most recent call last):
  File "/usr/share/glustolibs/io/scripts/file_dir_ops.py", line 1246, in <module>
    rc = args.func(args)
  File "/usr/share/glustolibs/io/scripts/file_dir_ops.py", line 374, in create_files
    base_file_name, file_types)
  File "/usr/share/glustolibs/io/scripts/file_dir_ops.py", line 341, in _create_files
    ret = pool.map(lambda file_tuple: _create_file(*file_tuple), files)
  File "/usr/lib64/python3.6/multiprocessing/pool.py", line 266, in map
    return self._map_async(func, iterable, mapstar, chunksize).get()
  File "/usr/lib64/python3.6/multiprocessing/pool.py", line 644, in get
    raise self._value
  File "/usr/lib64/python3.6/multiprocessing/pool.py", line 119, in worker
    result = (True, func(*args, **kwds))
  File "/usr/lib64/python3.6/multiprocessing/pool.py", line 44, in mapstar
    return list(map(*args))
  File "/usr/share/glustolibs/io/scripts/file_dir_ops.py", line 341, in <lambda>
    ret = pool.map(lambda file_tuple: _create_file(*file_tuple), files)
  File "/usr/share/glustolibs/io/scripts/file_dir_ops.py", line 270, in _create_file
    with open(file_abs_path, "w+") as new_file:
FileExistsError: [Errno 17] File exists: '/mnt/testvol_distributed_glusterfs/file1.txt'
```
This was because I/O logic was trying to create 2 files with the same
name from 2 clients.

Fix:
Modify logic to use counters to create files with different names.

Change-Id: I2896736d28f6bd17435f941088fd634347e3f4fd
Signed-off-by: kshithijiyer <kshithij.ki@gmail.com>

2 files changed, 5 insertions, 2 deletions

diff --git a/tests/functional/snapshot/test_mount_snap.py b/tests/functional/snapshot/test_mount_snap.py
index 9b0bf2bfe..ef918ba8b 100644
--- a/tests/functional/snapshot/test_mount_snap.py
+++ b/tests/functional/snapshot/test_mount_snap.py
@@ -84,14 +84,17 @@ class TestSnapMountSnapshot(GlusterBaseClass):
         g.log.info("Starting IO on all mounts...")
         g.log.info("mounts: %s", self.mounts)
         all_mounts_procs = []
+        self.counter = 1
         for mount_obj in self.mounts:
             cmd = ("/usr/bin/env python %s create_files "
-                   "-f 10 --base-file-name file %s" % (
+                   "-f 10 --base-file-name file%d %s" % (
                        self.script_upload_path,
+                       self.counter,
                        mount_obj.mountpoint))
             proc = g.run_async(mount_obj.client_system, cmd,
                                user=mount_obj.user)
             all_mounts_procs.append(proc)
+            self.counter += 100
 
         # Validate I/O
         self.assertTrue(
diff --git a/tests/functional/snapshot/test_restore_online_vol.py b/tests/functional/snapshot/test_restore_online_vol.py
index 2a7f39cae..2fa46012b 100644
--- a/tests/functional/snapshot/test_restore_online_vol.py
+++ b/tests/functional/snapshot/test_restore_online_vol.py
@@ -112,9 +112,9 @@ class SnapRSOnline(GlusterBaseClass):
                        "--num-of-files 2 %s" % (
                            self.script_upload_path,
                            self.counter, mount_obj.mountpoint))
-
                 proc = g.run_async(mount_obj.client_system, cmd,
                                    user=mount_obj.user)
+                self.counter += 100
                 self.all_mounts_procs.append(proc)
             self.io_validation_complete = False