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.
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.
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