On Tue, Nov 12, 2019 at 08:27:07PM -0800, John Hubbard wrote:
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
Reviewed-by: Ira Weiny ira.weiny@intel.com
mm/gup_benchmark.c | 9 ++++++--- tools/testing/selftests/vm/gup_benchmark.c | 6 +++++- 2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c index 7dd602d7f8db..7fc44d25eca7 100644 --- a/mm/gup_benchmark.c +++ b/mm/gup_benchmark.c @@ -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;
(gup->flags & 1) | FOLL_LONGTERM,
gup->flags | FOLL_LONGTERM, pages + i, NULL); break;
nr = get_user_pages(addr, nr, gup->flags & 1, pages + i,
nr = get_user_pages(addr, nr, gup->flags, pages + i, NULL); break;diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c index 485cf06ef013..389327e9b30a 100644 --- a/tools/testing/selftests/vm/gup_benchmark.c +++ b/tools/testing/selftests/vm/gup_benchmark.c @@ -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) -- 2.24.0