@@ -48,18 +48,21 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
nr = (next - addr) / PAGE_SIZE;
}
+ /* Filter out most gup flags: only allow a tiny subset here: */
+ gup->flags &= FOLL_WRITE;
+
switch (cmd) {
case GUP_FAST_BENCHMARK:
- nr = get_user_pages_fast(addr, nr, gup->flags & 1,
+ nr = get_user_pages_fast(addr, nr, gup->flags,
pages + i);
break;
case GUP_LONGTERM_BENCHMARK:
nr = get_user_pages(addr, nr,
- (gup->flags & 1) | FOLL_LONGTERM,
+ gup->flags | FOLL_LONGTERM,
pages + i, NULL);
break;
case GUP_BENCHMARK:
- nr = get_user_pages(addr, nr, gup->flags & 1, pages + i,
+ nr = get_user_pages(addr, nr, gup->flags, pages + i,
NULL);
break;
default:
@@ -18,6 +18,9 @@
#define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark)
#define GUP_BENCHMARK _IOWR('g', 3, struct gup_benchmark)
+/* Just the flags we need, copied from mm.h: */
+#define FOLL_WRITE 0x01 /* check pte is writable */
+
struct gup_benchmark {
__u64 get_delta_usec;
__u64 put_delta_usec;
@@ -85,7 +88,8 @@ int main(int argc, char **argv)
}
gup.nr_pages_per_call = nr_pages;
- gup.flags = write;
+ if (write)
+ gup.flags |= FOLL_WRITE;
fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR);
if (fd == -1)
Fix the gup benchmark flags to use the symbolic FOLL_WRITE, instead of a hard-coded "1" value. Also, clean up the filtering of gup flags a little, by just doing it once before issuing any of the get_user_pages*() calls. This makes it harder to overlook, instead of having little "gup_flags & 1" phrases in the function calls. Signed-off-by: John Hubbard <jhubbard@nvidia.com> --- mm/gup_benchmark.c | 9 ++++++--- tools/testing/selftests/vm/gup_benchmark.c | 6 +++++- 2 files changed, 11 insertions(+), 4 deletions(-)