On 1/31/22 15:00, Mike Kravetz wrote:

On 10/28/21 04:23, cgel.zte@gmail.com wrote:

...

From: Changcheng Deng deng.changcheng@zte.com.cn

Use swap() in order to make code cleaner. Issue found by coccinelle.

Reported-by: Zeal Robot zealci@zte.com.cn Signed-off-by: Changcheng Deng deng.changcheng@zte.com.cn

---

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?

Please disregard.

It was failing for me on v5.17-rc2, but I see it was fixed in linux-next with commit "selftests: vm: remove dependecy from internal kernel macros".

Sorry for the noise,