Swap is a function interface that provides exchange function. To avoid
code duplication, we can use swap function.
./arch/um/os-Linux/sigio.c:81:28-29: WARNING opportunity for swap().
Reported-by: Abaci Robot <[email protected]>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=7607
Signed-off-by: Jiapeng Chong <[email protected]>
---
arch/um/os-Linux/sigio.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/arch/um/os-Linux/sigio.c b/arch/um/os-Linux/sigio.c
index 9e71794839e8..1eb15f3cfdc8 100644
--- a/arch/um/os-Linux/sigio.c
+++ b/arch/um/os-Linux/sigio.c
@@ -50,7 +50,7 @@ static struct pollfds all_sigio_fds;
static int write_sigio_thread(void *unused)
{
- struct pollfds *fds, tmp;
+ struct pollfds *fds;
struct pollfd *p;
int i, n, respond_fd;
char c;
@@ -77,9 +77,7 @@ static int write_sigio_thread(void *unused)
"write_sigio_thread : "
"read on socket failed, "
"err = %d\n", errno);
- tmp = current_poll;
- current_poll = next_poll;
- next_poll = tmp;
+ swap(current_poll, next_poll);
respond_fd = sigio_private[1];
}
else {
--
2.20.1.7.g153144c
On Wed, 2023-11-22 at 11:25 +0800, Jiapeng Chong wrote:
> Swap is a function interface that provides exchange function. To avoid
> code duplication, we can use swap function.
>
> ./arch/um/os-Linux/sigio.c:81:28-29: WARNING opportunity for swap().
>
Hm. There's already a use of swap() here in this file, but I actually
think we should revert that? This is basically userspace code, not
kernel code, so I don't think it should include linux headers, even if
those happen to be "standalone enough" right now to work.
johannes
Hi Jiapeng,
kernel test robot noticed the following build errors:
[auto build test ERROR on wireless-next/main]
[also build test ERROR on linus/master v6.7-rc2 next-20231122]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Jiapeng-Chong/um-Use-swap-instead-of-open-coding-it/20231122-113031
base: https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next.git main
patch link: https://lore.kernel.org/r/20231122032518.53305-1-jiapeng.chong%40linux.alibaba.com
patch subject: [PATCH] um: Use swap() instead of open coding it
config: um-randconfig-002-20231122 (https://download.01.org/0day-ci/archive/20231123/[email protected]/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231123/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
>> arch/um/os-Linux/sigio.c:80:5: error: call to undeclared function 'swap'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
80 | swap(current_poll, next_poll);
| ^
arch/um/os-Linux/sigio.c:80:5: note: did you mean 'swab'?
/usr/include/unistd.h:1168:13: note: 'swab' declared here
1168 | extern void swab (const void *__restrict __from, void *__restrict __to,
| ^
1 error generated.
vim +/swap +80 arch/um/os-Linux/sigio.c
50
51 static int write_sigio_thread(void *unused)
52 {
53 struct pollfds *fds;
54 struct pollfd *p;
55 int i, n, respond_fd;
56 char c;
57
58 os_fix_helper_signals();
59 fds = ¤t_poll;
60 while (1) {
61 n = poll(fds->poll, fds->used, -1);
62 if (n < 0) {
63 if (errno == EINTR)
64 continue;
65 printk(UM_KERN_ERR "write_sigio_thread : poll returned "
66 "%d, errno = %d\n", n, errno);
67 }
68 for (i = 0; i < fds->used; i++) {
69 p = &fds->poll[i];
70 if (p->revents == 0)
71 continue;
72 if (p->fd == sigio_private[1]) {
73 CATCH_EINTR(n = read(sigio_private[1], &c,
74 sizeof(c)));
75 if (n != sizeof(c))
76 printk(UM_KERN_ERR
77 "write_sigio_thread : "
78 "read on socket failed, "
79 "err = %d\n", errno);
> 80 swap(current_poll, next_poll);
81 respond_fd = sigio_private[1];
82 }
83 else {
84 respond_fd = write_sigio_fds[1];
85 fds->used--;
86 memmove(&fds->poll[i], &fds->poll[i + 1],
87 (fds->used - i) * sizeof(*fds->poll));
88 }
89
90 CATCH_EINTR(n = write(respond_fd, &c, sizeof(c)));
91 if (n != sizeof(c))
92 printk(UM_KERN_ERR "write_sigio_thread : "
93 "write on socket failed, err = %d\n",
94 errno);
95 }
96 }
97
98 return 0;
99 }
100
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Jiapeng,
kernel test robot noticed the following build errors:
[auto build test ERROR on wireless-next/main]
[also build test ERROR on linus/master v6.7-rc2 next-20231122]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Jiapeng-Chong/um-Use-swap-instead-of-open-coding-it/20231122-113031
base: https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next.git main
patch link: https://lore.kernel.org/r/20231122032518.53305-1-jiapeng.chong%40linux.alibaba.com
patch subject: [PATCH] um: Use swap() instead of open coding it
config: um-randconfig-001-20231122 (https://download.01.org/0day-ci/archive/20231123/[email protected]/config)
compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project.git 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231123/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
>> arch/um/os-Linux/sigio.c:80:5: error: call to undeclared function 'swap'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]
swap(current_poll, next_poll);
^
arch/um/os-Linux/sigio.c:80:5: note: did you mean 'swab'?
/usr/include/unistd.h:1168:13: note: 'swab' declared here
extern void swab (const void *__restrict __from, void *__restrict __to,
^
1 error generated.
vim +/swap +80 arch/um/os-Linux/sigio.c
50
51 static int write_sigio_thread(void *unused)
52 {
53 struct pollfds *fds;
54 struct pollfd *p;
55 int i, n, respond_fd;
56 char c;
57
58 os_fix_helper_signals();
59 fds = ¤t_poll;
60 while (1) {
61 n = poll(fds->poll, fds->used, -1);
62 if (n < 0) {
63 if (errno == EINTR)
64 continue;
65 printk(UM_KERN_ERR "write_sigio_thread : poll returned "
66 "%d, errno = %d\n", n, errno);
67 }
68 for (i = 0; i < fds->used; i++) {
69 p = &fds->poll[i];
70 if (p->revents == 0)
71 continue;
72 if (p->fd == sigio_private[1]) {
73 CATCH_EINTR(n = read(sigio_private[1], &c,
74 sizeof(c)));
75 if (n != sizeof(c))
76 printk(UM_KERN_ERR
77 "write_sigio_thread : "
78 "read on socket failed, "
79 "err = %d\n", errno);
> 80 swap(current_poll, next_poll);
81 respond_fd = sigio_private[1];
82 }
83 else {
84 respond_fd = write_sigio_fds[1];
85 fds->used--;
86 memmove(&fds->poll[i], &fds->poll[i + 1],
87 (fds->used - i) * sizeof(*fds->poll));
88 }
89
90 CATCH_EINTR(n = write(respond_fd, &c, sizeof(c)));
91 if (n != sizeof(c))
92 printk(UM_KERN_ERR "write_sigio_thread : "
93 "write on socket failed, err = %d\n",
94 errno);
95 }
96 }
97
98 return 0;
99 }
100
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki