exec_target.c

 1// SPDX-License-Identifier: GPL-2.0+
 2
 3/*
 4 * Part of fork context switch microbenchmark.
 5 *
 6 * Copyright 2018, Anton Blanchard, IBM Corp.
 7 */
 8
 9#define _GNU_SOURCE
10#include <sys/syscall.h>
11
12void _start(void)
13{
14	asm volatile (
15		"li %%r0, %[sys_exit];"
16		"li %%r3, 0;"
17		"sc;"
18		:
19		: [sys_exit] "i" (SYS_exit)
20		/*
21		 * "sc" will clobber r0, r3-r13, cr0, ctr, xer and memory.
22		 * Even though sys_exit never returns, handle clobber
23		 * registers.
24		 */
25		: "r0", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10",
26		  "r11", "r12", "r13", "cr0", "ctr", "xer", "memory"
27	);
28}