[PATCH 1/3] powerpc: Replace NR_syscalls macro from asm/unistd.h

Firoz Khan firoz.khan at linaro.org
Fri Sep 14 18:32:58 AEST 2018


__NR_syscalls macro holds the number of system call exist in POWERPC
architecture. This macro is currently the part of asm/unistd.h file.
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 number of system call information. So we have two option to update
__NR_syscalls value.

1. Update __NR_syscalls in asm/unistd.h manually by counting the
   no.of system calls. No need to update __NR_syscalls untill
   we either add a new system call or delete an existing system
   call.

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

The 2nd option will be the recommended one. For that, I moved the
NR_syscalls macro from asm/unistd.h to uapi/asm/unistd.h. The macro
name also changed form NR_syscalls to __NR_syscalls 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.

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

diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index c19379f..54732f9 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -11,8 +11,7 @@
 
 #include <uapi/asm/unistd.h>
 
-
-#define NR_syscalls		389
+#define NR_syscalls  __NR_syscalls
 
 #define __NR__exit __NR_exit
 
diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h
index 985534d..f999df2 100644
--- a/arch/powerpc/include/uapi/asm/unistd.h
+++ b/arch/powerpc/include/uapi/asm/unistd.h
@@ -401,4 +401,6 @@
 #define __NR_rseq		387
 #define __NR_io_pgetevents	388
 
+#define __NR_syscalls           389
+
 #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
-- 
1.9.1



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