Commit a5883fa9 authored by David Hildenbrand's avatar David Hildenbrand Committed by Andrew Morton
Browse files

selftests/mm: gup_tests: option to GUP all pages in a single call 

We recently missed detecting an issue during early testing because the
default (!all) tests would not trigger it and even when running "all"
tests it only would happen sometimes because of races.

So let's allow for an easy way to specify "GUP all pages in a single
call", extend the test matrix and extend our default (!all) tests.

By GUP'ing all pages in a single call, with the default size of 128MiB
we'll cover multiple leaf page tables / PMDs on architectures with sane
THP sizes.

Link: https://lkml.kernel.org/r/20250910093051.1693097-1-david@redhat.com


Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 9d003dec

tools/testing/selftests/mm/gup_test.c

+2 −0
Original line number Diff line number Diff line
@@ -139,6 +139,8 @@ int main(int argc, char **argv) 
			break;

		case 'n':

			nr_pages = atoi(optarg);

			if (nr_pages < 0)

				nr_pages = size / psize();

			break;

		case 't':

			thp = 1;

tools/testing/selftests/mm/run_vmtests.sh

+5 −3
Original line number Diff line number Diff line
@@ -138,7 +138,7 @@ run_gup_matrix() { 
                    # -n: How many pages to fetch together?  512 is special

                    # because it's default thp size (or 2M on x86), 123 to

                    # just test partial gup when hit a huge in whatever form

                    for num in "-n 1" "-n 512" "-n 123"; do

                    for num in "-n 1" "-n 512" "-n 123" "-n -1"; do

                        CATEGORY="gup_test" run_test ./gup_test \

                                $huge $test_cmd $write $share $num

                    done
@@ -314,9 +314,11 @@ if $RUN_ALL; then 
    run_gup_matrix

else

    # get_user_pages_fast() benchmark

    CATEGORY="gup_test" run_test ./gup_test -u

    CATEGORY="gup_test" run_test ./gup_test -u -n 1

    CATEGORY="gup_test" run_test ./gup_test -u -n -1

    # pin_user_pages_fast() benchmark

    CATEGORY="gup_test" run_test ./gup_test -a

    CATEGORY="gup_test" run_test ./gup_test -a -n 1

    CATEGORY="gup_test" run_test ./gup_test -a -n -1

fi

# Dump pages 0, 19, and 4096, using pin_user_pages:

CATEGORY="gup_test" run_test ./gup_test -ct -F 0x1 0 19 0x1000