usemem: Output a message after punch holes done

When I use punch holes to setup a test page fragmentation environment, I
didn't know when the punch holes done.  I can only get this information
through top or something else.

This commit add code to output a message after punch holes done to
handle this issue.

Signed-off-by: Hui Zhu <teawater@antfin.com>
Signed-off-by: Wu Fengguang <wfg@mail.ustc.edu.cn>

1 files changed, 2 insertions, 0 deletions

diff --git a/usemem.c b/usemem.c
index 5b90aae..0c76d17 100644
--- a/usemem.c
+++ b/usemem.c
@@ -791,6 +791,8 @@ long do_units(void)
 			for (i = 0; i < nptr; i++)
 				do_punch_holes(ptrs[i], lens[i]);
 		}
+		printf("punch holes done\n");
+		fflush(stdout);
 	}
 
 	while (sleep_secs)