[PATCH] x86-64: Auto compute __NR_syscall_max at compile time

No need to maintain it anymore

Signed-off-by: Andi Kleen <ak@suse.de>

arch/x86_64/kernel/asm-offsets.c

@@ -21,6 +21,14 @@
 
 #define BLANK() asm volatile("\n->" : : )
 
+#define __NO_STUBS 1
+#undef __SYSCALL
+#undef _ASM_X86_64_UNISTD_H_
+#define __SYSCALL(nr, sym) [nr] = 1,
+static char syscalls[] = {
+#include <asm/unistd.h>
+};
+
 int main(void)
 {
 #define ENTRY(entry) DEFINE(tsk_ ## entry, offsetof(struct task_struct, entry))
@@ -71,5 +79,7 @@ int main(void)
 	DEFINE(TSS_ist, offsetof(struct tss_struct, ist));
 	BLANK();
 	DEFINE(crypto_tfm_ctx_offset, offsetof(struct crypto_tfm, __crt_ctx));
+	BLANK();
+	DEFINE(__NR_syscall_max, sizeof(syscalls) - 1);
 	return 0;
 }

arch/x86_64/kernel/syscall.c

@@ -3,6 +3,7 @@
 #include <linux/linkage.h>
 #include <linux/sys.h>
 #include <linux/cache.h>
+#include <asm/asm-offsets.h>
 
 #define __NO_STUBS
 

include/asm-x86_64/unistd.h

@@ -620,8 +620,6 @@ __SYSCALL(__NR_vmsplice, sys_vmsplice)
 #define __NR_move_pages		279
 __SYSCALL(__NR_move_pages, sys_move_pages)
 
-#define __NR_syscall_max __NR_move_pages
-
 #ifndef __NO_STUBS
 #define __ARCH_WANT_OLD_READDIR
 #define __ARCH_WANT_OLD_STAT