diff mbox series

[v3,1/3] sh: add __NR_syscalls along with NR_syscalls

Message ID 1542169930-24118-2-git-send-email-firoz.khan@linaro.org (mailing list archive)
State New, archived
Headers show
Series sh: system call table generation support | expand

Commit Message

Firoz Khan Nov. 14, 2018, 4:32 a.m. UTC
NR_syscalls macro holds the number of system call exist
in sh architecture. We have to change the value of NR-
_syscalls, if we add or delete a system call.

One of the patch in this patch series has a script which
will generate a uapi header based on syscall.tbl file.
The syscall.tbl file contains the total number of system
calls information. So we have two option to update NR_sy-
scalls value.

1. Update NR_syscalls in asm/unistd.h manually by count-
   ing the no.of system calls. No need to update NR_sys-
   calls until we either add a new system call or delete
   existing system call.

2. We can keep this feature it above mentioned script,
   that will count the number of syscalls and keep it in
   a generated file. In this case we don't need to expli-
   citly update NR_syscalls in asm/unistd.h file.

The 2nd option will be the recommended one. For that, I
added the __NR_syscalls macro in uapi/asm/unistd_32/64.h
along with NR_syscalls which is moved to asm/unistd.h.
The macro __NR_syscalls also added for making the name
convention same across all architecture. While __NR_sys-
calls isn't strictly part of the uapi, having it as part
of the generated header to simplifies the implementation.
We also need to enclose this macro with #ifdef __KERNEL__
to avoid side effects.

Signed-off-by: Firoz Khan <firoz.khan@linaro.org>
---
 arch/sh/include/asm/unistd.h         | 2 ++
 arch/sh/include/uapi/asm/unistd_32.h | 4 +++-
 arch/sh/include/uapi/asm/unistd_64.h | 4 +++-
 3 files changed, 8 insertions(+), 2 deletions(-)

Comments

Arnd Bergmann Nov. 19, 2018, 4:50 p.m. UTC | #1
On Wed, Nov 14, 2018 at 5:32 AM Firoz Khan <firoz.khan@linaro.org> wrote:
>
> NR_syscalls macro holds the number of system call exist
> in sh architecture. We have to change the value of NR-
> _syscalls, if we add or delete a system call.
>
> One of the patch in this patch series has a script which
> will generate a uapi header based on syscall.tbl file.
> The syscall.tbl file contains the total number of system
> calls information. So we have two option to update NR_sy-
> scalls value.
>
> 1. Update NR_syscalls in asm/unistd.h manually by count-
>    ing the no.of system calls. No need to update NR_sys-
>    calls until we either add a new system call or delete
>    existing system call.
>
> 2. We can keep this feature it above mentioned script,
>    that will count the number of syscalls and keep it in
>    a generated file. In this case we don't need to expli-
>    citly update NR_syscalls in asm/unistd.h file.
>
> The 2nd option will be the recommended one. For that, I
> added the __NR_syscalls macro in uapi/asm/unistd_32/64.h
> along with NR_syscalls which is moved to asm/unistd.h.
> The macro __NR_syscalls also added for making the name
> convention same across all architecture. While __NR_sys-
> calls isn't strictly part of the uapi, having it as part
> of the generated header to simplifies the implementation.
> We also need to enclose this macro with #ifdef __KERNEL__
> to avoid side effects.
>
> Signed-off-by: Firoz Khan <firoz.khan@linaro.org>

Looks correct to me, but since there are only three references to
'NR_syscalls' in arch/sh, I wonder if we should just replace it with
__NR_syscalls in the same patch.

       Arnd
Firoz Khan Nov. 20, 2018, 7:05 a.m. UTC | #2
Hi Arnd,

On Mon, 19 Nov 2018 at 22:21, Arnd Bergmann <arnd@arndb.de> wrote:
>
> On Wed, Nov 14, 2018 at 5:32 AM Firoz Khan <firoz.khan@linaro.org> wrote:
> >
> > NR_syscalls macro holds the number of system call exist
> > in sh architecture. We have to change the value of NR-
> > _syscalls, if we add or delete a system call.
> >
> > One of the patch in this patch series has a script which
> > will generate a uapi header based on syscall.tbl file.
> > The syscall.tbl file contains the total number of system
> > calls information. So we have two option to update NR_sy-
> > scalls value.
> >
> > 1. Update NR_syscalls in asm/unistd.h manually by count-
> >    ing the no.of system calls. No need to update NR_sys-
> >    calls until we either add a new system call or delete
> >    existing system call.
> >
> > 2. We can keep this feature it above mentioned script,
> >    that will count the number of syscalls and keep it in
> >    a generated file. In this case we don't need to expli-
> >    citly update NR_syscalls in asm/unistd.h file.
> >
> > The 2nd option will be the recommended one. For that, I
> > added the __NR_syscalls macro in uapi/asm/unistd_32/64.h
> > along with NR_syscalls which is moved to asm/unistd.h.
> > The macro __NR_syscalls also added for making the name
> > convention same across all architecture. While __NR_sys-
> > calls isn't strictly part of the uapi, having it as part
> > of the generated header to simplifies the implementation.
> > We also need to enclose this macro with #ifdef __KERNEL__
> > to avoid side effects.
> >
> > Signed-off-by: Firoz Khan <firoz.khan@linaro.org>
>
> Looks correct to me, but since there are only three references to
> 'NR_syscalls' in arch/sh, I wonder if we should just replace it with
> __NR_syscalls in the same patch.

This is the approach I had initially, But someone pointed out that doing
this way - #define NR_syscalls    __NR_syscalls would be better. The
only difference is here the number of occurrence 3 and there 5-7
occurrence of NR_syscalls.

Thanks
Firoz

>
>        Arnd
diff mbox series

Patch

diff --git a/arch/sh/include/asm/unistd.h b/arch/sh/include/asm/unistd.h
index a99234b..a97f93c 100644
--- a/arch/sh/include/asm/unistd.h
+++ b/arch/sh/include/asm/unistd.h
@@ -5,6 +5,8 @@ 
 #  include <asm/unistd_64.h>
 # endif
 
+#define NR_syscalls	__NR_syscalls
+
 # define __ARCH_WANT_NEW_STAT
 # define __ARCH_WANT_OLD_READDIR
 # define __ARCH_WANT_OLD_STAT
diff --git a/arch/sh/include/uapi/asm/unistd_32.h b/arch/sh/include/uapi/asm/unistd_32.h
index 58f04cf..31c85aa 100644
--- a/arch/sh/include/uapi/asm/unistd_32.h
+++ b/arch/sh/include/uapi/asm/unistd_32.h
@@ -396,6 +396,8 @@ 
 #define __NR_preadv2		381
 #define __NR_pwritev2		382
 
-#define NR_syscalls 383
+#ifdef __KERNEL__
+#define __NR_syscalls		383
+#endif
 
 #endif /* __ASM_SH_UNISTD_32_H */
diff --git a/arch/sh/include/uapi/asm/unistd_64.h b/arch/sh/include/uapi/asm/unistd_64.h
index 6f809a5..75da548 100644
--- a/arch/sh/include/uapi/asm/unistd_64.h
+++ b/arch/sh/include/uapi/asm/unistd_64.h
@@ -416,6 +416,8 @@ 
 #define __NR_preadv2		392
 #define __NR_pwritev2		393
 
-#define NR_syscalls 394
+#ifdef __KERNEL__
+#define __NR_syscalls		394
+#endif
 
 #endif /* __ASM_SH_UNISTD_64_H */