On 10/28/21 04:23, cgel.zte@xxxxxxxxx wrote:
> From: Changcheng Deng <deng.changcheng@xxxxxxxxxx>
>
> Use swap() in order to make code cleaner. Issue found by coccinelle.
>
> Reported-by: Zeal Robot <zealci@xxxxxxxxxx>
> Signed-off-by: Changcheng Deng <deng.changcheng@xxxxxxxxxx>
> ---
> tools/testing/selftests/vm/userfaultfd.c | 10 ++--------
> 1 file changed, 2 insertions(+), 8 deletions(-)
>
> diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c
> index 8a09057d2f22..41dfe6f4ebfb 100644
> --- a/tools/testing/selftests/vm/userfaultfd.c
> +++ b/tools/testing/selftests/vm/userfaultfd.c
> @@ -1413,7 +1413,6 @@ static void userfaultfd_pagemap_test(unsigned int test_pgsize)
> static int userfaultfd_stress(void)
> {
> void *area;
> - char *tmp_area;
> unsigned long nr;
> struct uffdio_register uffdio_register;
> struct uffd_stats uffd_stats[nr_cpus];
> @@ -1524,13 +1523,8 @@ static int userfaultfd_stress(void)
> count_verify[nr], nr);
>
> /* prepare next bounce */
> - tmp_area = area_src;
> - area_src = area_dst;
> - area_dst = tmp_area;
> -
> - tmp_area = area_src_alias;
> - area_src_alias = area_dst_alias;
> - area_dst_alias = tmp_area;
> + swap(area_src, area_dst);
> + swap(area_src_alias, area_dst_alias);
>
> uffd_stats_report(uffd_stats, nr_cpus);
> }
Sorry for the late comment/question.
Where is the test supposed to get the definition of swap()? When trying to
build, I get:
gcc -Wall -I ../../../../usr/include -no-pie userfaultfd.c -lrt -lpthread -o /home/mkravetz/tmp/linux-stable/tools/testing/selftests/vm/userfaultfd
userfaultfd.c: In function ‘userfaultfd_stress’:
userfaultfd.c:1530:3: warning: implicit declaration of function ‘swap’; did you mean ‘swab’? [-Wimplicit-function-declaration]
1530 | swap(area_src, area_dst);
| ^~~~
| swab
/usr/bin/ld: /tmp/ccPiwPM0.o: in function `userfaultfd_stress':
userfaultfd.c:(.text+0x4b6d): undefined reference to `swap'
/usr/bin/ld: userfaultfd.c:(.text+0x4b8b): undefined reference to `swap'
collect2: error: ld returned 1 exit status
make[1]: *** [../lib.mk:146: /home/mkravetz/tmp/linux-stable/tools/testing/selftests/vm/userfaultfd] Error 1
As far as I can see, swap is only defined in 'include/linux/minmax.h'.
However, that is not part of the user API and not available to the tests.
What am I missing?
--
Mike Kravetz
