NR_SYSCALLS macro holds the number of system call exist in alpha 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- CALLS 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.h along with NR_SYSCALLS asm/unistd.h. The macro __NR_syscalls also added for making the name convention same across all architecture. While __NR_syscalls 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/alpha/include/asm/unistd.h | 2 +- arch/alpha/include/uapi/asm/unistd.h | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/alpha/include/asm/unistd.h b/arch/alpha/include/asm/unistd.h index 4f0ceb3..21b706a 100644 --- a/arch/alpha/include/asm/unistd.h +++ b/arch/alpha/include/asm/unistd.h @@ -4,7 +4,7 @@
#include <uapi/asm/unistd.h>
-#define NR_SYSCALLS 523 +#define NR_SYSCALLS __NR_syscalls
#define __ARCH_WANT_NEW_STAT #define __ARCH_WANT_OLD_READDIR diff --git a/arch/alpha/include/uapi/asm/unistd.h b/arch/alpha/include/uapi/asm/unistd.h index 47c65f1..ab40aa6 100644 --- a/arch/alpha/include/uapi/asm/unistd.h +++ b/arch/alpha/include/uapi/asm/unistd.h @@ -465,4 +465,8 @@ #define __NR_pwritev2 521 #define __NR_statx 522
+#ifdef __KERNEL__ +#define __NR_syscalls 523 +#endif + #endif /* _UAPI_ALPHA_UNISTD_H */