mm/gup_benchmark: use proper FOLL_WRITE flags instead of hard-coding "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.

Link: http://lkml.kernel.org/r/20200107224558.2362728-22-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
John Hubbard 2020-01-30 22:13:32 -08:00 committed by Linus Torvalds
parent aa4b87fe9e
commit bdffe23eee
2 changed files with 11 additions and 4 deletions

View File

@ -49,18 +49,21 @@ 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:

View File

@ -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)