sched_setaffinity: use the same style with glibc's

Call getpid() in INTERNAL_SYSCALL will break the argument regs,
because gcc couldn't save destoryed regs for system call asm.

Ref to glibc, we could just remove all the check code.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>

libc/sysdeps/linux/common/sched_setaffinity.c

@@ -27,42 +27,8 @@
 static __always_inline _syscall3(int, __syscall_sched_setaffinity, __kernel_pid_t, pid,
 				 size_t, cpusetsize, const cpu_set_t *, cpuset)
 
-static size_t __kernel_cpumask_size;
-
 int sched_setaffinity(pid_t pid, size_t cpusetsize, const cpu_set_t *cpuset)
 {
-	size_t cnt;
-	int res;
-	size_t psize = 128;
-	void *p = alloca (psize);
-
-	if (unlikely (__kernel_cpumask_size == 0)) {
-
-		INTERNAL_SYSCALL_DECL (err);
-		while (res = INTERNAL_SYSCALL (sched_getaffinity, err, 3, getpid (),
-					       psize, p),
-		       INTERNAL_SYSCALL_ERROR_P (res, err)
-		       && INTERNAL_SYSCALL_ERRNO (res, err) == EINVAL)
-			p = extend_alloca (p, psize, 2 * psize);
-
-		if (res == 0 || INTERNAL_SYSCALL_ERROR_P (res, err)) {
-			__set_errno (INTERNAL_SYSCALL_ERRNO (res, err));
-			return -1;
-		}
-
-		__kernel_cpumask_size = res;
-	}
-
-	/* We now know the size of the kernel cpumask_t.  Make sure the user
-	   does not request to set a bit beyond that.  */
-	for (cnt = __kernel_cpumask_size; cnt < cpusetsize; ++cnt)
-		if (((char *) cpuset)[cnt] != '\0') {
-			/* Found a nonzero byte.  This means the user request cannot be
-			   fulfilled.  */
-			__set_errno (EINVAL);
-			return -1;
-		}
-
 	return __syscall_sched_setaffinity(pid, cpusetsize, cpuset);
 }
 #endif