From 17de1e559cf1eb01d5d90afd3064d5a280060f6f Mon Sep 17 00:00:00 2001 From: Joel Savitz Date: Mon, 9 May 2022 18:20:47 -0700 Subject: selftests: clarify common error when running gup_test The gup_test binary will fail showing only the output of perror("open") in the case that /sys/kernel/debug/gup_test is not found. This will almost always be due to CONFIG_GUP_TEST not being set, which enables compilation of a kernel that provides this file. Add a short error message to clarify this failure and point the user to the solution. Link: https://lkml.kernel.org/r/20220502224942.995427-1-jsavitz@redhat.com Signed-off-by: Joel Savitz Cc: Shuah Khan Cc: Nico Pache Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/gup_test.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/vm/gup_test.c b/tools/testing/selftests/vm/gup_test.c index 593262555e18..6bb36ca71cb5 100644 --- a/tools/testing/selftests/vm/gup_test.c +++ b/tools/testing/selftests/vm/gup_test.c @@ -21,6 +21,8 @@ #define FOLL_WRITE 0x01 /* check pte is writable */ #define FOLL_TOUCH 0x02 /* mark page accessed */ +#define GUP_TEST_FILE "/sys/kernel/debug/gup_test" + static unsigned long cmd = GUP_FAST_BENCHMARK; static int gup_fd, repeats = 1; static unsigned long size = 128 * MB; -- cgit v1.2.3