2021-10-28 11:27:45

by CGEL

[permalink] [raw]
Subject: [PATCH] userfaultfd/selftests: use swap() to make code cleaner

From: Changcheng Deng <[email protected]>

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

Reported-by: Zeal Robot <[email protected]>
Signed-off-by: Changcheng Deng <[email protected]>
---
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);
}
--
2.25.1


2021-10-28 13:18:12

by Shuah Khan

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Subject: Re: [PATCH] userfaultfd/selftests: use swap() to make code cleaner

On 10/28/21 5:23 AM, [email protected] wrote:
> From: Changcheng Deng <[email protected]>
>
> Use swap() in order to make code cleaner. Issue found by coccinelle.

Please include the coccinelle log.
>
> Reported-by: Zeal Robot <[email protected]>
> Signed-off-by: Changcheng Deng <[email protected]>
> ---
> 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);
> }
>

thanks,
-- Shuah

2022-02-01 20:54:03

by Mike Kravetz

[permalink] [raw]
Subject: Re: [PATCH] userfaultfd/selftests: use swap() to make code cleaner

On 10/28/21 04:23, [email protected] wrote:
> From: Changcheng Deng <[email protected]>
>
> Use swap() in order to make code cleaner. Issue found by coccinelle.
>
> Reported-by: Zeal Robot <[email protected]>
> Signed-off-by: Changcheng Deng <[email protected]>
> ---
> 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

2022-02-02 00:08:37

by Mike Kravetz

[permalink] [raw]
Subject: Re: [PATCH] userfaultfd/selftests: use swap() to make code cleaner

On 1/31/22 15:00, Mike Kravetz wrote:
> On 10/28/21 04:23, [email protected] wrote:
>> From: Changcheng Deng <[email protected]>
>>
>> Use swap() in order to make code cleaner. Issue found by coccinelle.
>>
>> Reported-by: Zeal Robot <[email protected]>
>> Signed-off-by: Changcheng Deng <[email protected]>
>> ---
>> 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,
--
Mike Kravetz