[PATCH 5/6] tools/gup_benchmark: Add MAP_SHARED option

From: Keith Busch
Date: Wed Oct 10 2018 - 16:00:42 EST


This patch adds a new benchmark option, -S, to request MAP_SHARED. This
can be used to compare with MAP_PRIVATE, or for files that require this
option, like dax.

Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
---
tools/testing/selftests/vm/gup_benchmark.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c
index b675a3d60975..24528b54549d 100644
--- a/tools/testing/selftests/vm/gup_benchmark.c
+++ b/tools/testing/selftests/vm/gup_benchmark.c
@@ -32,11 +32,11 @@ int main(int argc, char **argv)
struct gup_benchmark gup;
unsigned long size = 128 * MB;
int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
- int cmd = GUP_FAST_BENCHMARK;
+ int cmd = GUP_FAST_BENCHMARK, flags = MAP_PRIVATE;
char *file = "/dev/zero";
char *p;

- while ((opt = getopt(argc, argv, "m:r:n:f:tTLU")) != -1) {
+ while ((opt = getopt(argc, argv, "m:r:n:f:tTLUS")) != -1) {
switch (opt) {
case 'm':
size = atoi(optarg) * MB;
@@ -65,6 +65,10 @@ int main(int argc, char **argv)
case 'f':
file = optarg;
break;
+ case 'S':
+ flags &= ~MAP_PRIVATE;
+ flags |= MAP_SHARED;
+ break;
default:
return -1;
}
@@ -81,7 +85,7 @@ int main(int argc, char **argv)
if (fd == -1)
perror("open"), exit(1);

- p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, filed, 0);
+ p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
if (p == MAP_FAILED)
perror("mmap"), exit(1);
gup.addr = (unsigned long)p;
--
2.14.4