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

From: Firoz Khan <firoz.khan@linaro.org>
To: linux-sh@vger.kernel.org,
	Yoshinori Sato <ysato@users.sourceforge.jp>,
	Rich Felker <dalias@libc.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Philippe Ombredanne <pombredanne@nexb.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Kate Stewart <kstewart@linuxfoundation.org>
Cc: y2038@lists.linaro.org, linux-kernel@vger.kernel.org,
	linux-arch@vger.kernel.org, arnd@arndb.de,
	deepa.kernel@gmail.com, marcin.juszkiewicz@linaro.org,
	firoz.khan@linaro.org
Subject: [PATCH v3 1/3] sh: add __NR_syscalls along with NR_syscalls
Date: Wed, 14 Nov 2018 04:44:08 +0000	[thread overview]
Message-ID: <1542169930-24118-2-git-send-email-firoz.khan@linaro.org> (raw)
In-Reply-To: <1542169930-24118-1-git-send-email-firoz.khan@linaro.org>

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(-)

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 */
-- 
1.9.1
