From: Yang Guang <[email protected]>
Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid
opencoding it.
Reported-by: Zeal Robot <[email protected]>
Signed-off-by: Yang Guang <[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 {
--
2.30.2
Hi,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on rw-uml/linux-next]
[also build test ERROR on v5.15 next-20211104]
[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]
url: https://github.com/0day-ci/linux/commits/davidcomponentone-gmail-com/um-use-swap-to-make-code-cleaner/20211104-141655
base: https://git.kernel.org/pub/scm/linux/kernel/git/rw/uml.git linux-next
config: um-x86_64_defconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
# https://github.com/0day-ci/linux/commit/0daa3d13fe02d69f3d42d17d176edb0043136241
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review davidcomponentone-gmail-com/um-use-swap-to-make-code-cleaner/20211104-141655
git checkout 0daa3d13fe02d69f3d42d17d176edb0043136241
# save the attached .config to linux build tree
make W=1 ARCH=um SUBARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All errors (new ones prefixed by >>):
arch/um/os-Linux/sigio.c: In function 'write_sigio_thread':
>> arch/um/os-Linux/sigio.c:80:5: error: implicit declaration of function 'swap'; did you mean 'swab'? [-Werror=implicit-function-declaration]
80 | swap(current_poll, next_poll);
| ^~~~
| swab
cc1: some warnings being treated as errors
vim +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, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
On 04/11/2021 06:16, [email protected] wrote:
> From: Yang Guang <[email protected]>
>
> Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid
> opencoding it.
>
> Reported-by: Zeal Robot <[email protected]>
> Signed-off-by: Yang Guang <[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 {
>
You should include minmax.h for the swap macro. While there is a very significant likelihood that it will be pulled up by another something else, it is better to do that explicitly.
--
Anton R. Ivanov
Cambridgegreys Limited. Registered in England. Company Number 10273661
https://www.cambridgegreys.com/
From: Yang Guang <[email protected]>
Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid
opencoding it.
Reported-by: Zeal Robot <[email protected]>
Signed-off-by: Yang Guang <[email protected]>
---
arch/um/os-Linux/sigio.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/arch/um/os-Linux/sigio.c b/arch/um/os-Linux/sigio.c
index 9e71794839e8..37d60e72cf26 100644
--- a/arch/um/os-Linux/sigio.c
+++ b/arch/um/os-Linux/sigio.c
@@ -3,6 +3,7 @@
* Copyright (C) 2002 - 2008 Jeff Dike (jdike@{addtoit,linux.intel}.com)
*/
+#include <linux/minmax.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
@@ -50,7 +51,7 @@ 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 +78,7 @@ 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 {
--
2.30.2
From: Yang Guang
> Sent: 05 November 2021 06:19
>
> Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid
> opencoding it.
Is there any real point to any of these patches??
If I'm reading a 'random' piece of code I now have to assume
that swap() is something that 'magically' exchanges two items.
This requires more brain-power than parsing the three lines
that do an actual swap.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)