xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/prctl/prctl09.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved.
4  * Author: Yang Xu <[email protected]>
5  */
6 
7 /*\
8  * [Description]
9  *
10  * This is a timer sample test that timer slack is 200us.
11  */
12 
13 #include <errno.h>
14 #include <sys/prctl.h>
15 #include "lapi/prctl.h"
16 #include "tst_timer_test.h"
17 
sample_fn(int clk_id,long long usec)18 static int sample_fn(int clk_id, long long usec)
19 {
20 	struct timespec t = tst_timespec_from_us(usec);
21 
22 	tst_timer_start(clk_id);
23 	TEST(nanosleep(&t, NULL));
24 	tst_timer_stop();
25 	tst_timer_sample();
26 
27 	if (TST_RET != 0) {
28 		tst_res(TFAIL | TTERRNO,
29 			"nanosleep() returned %li", TST_RET);
30 		return 1;
31 	}
32 
33 	return 0;
34 }
35 
setup(void)36 static void setup(void)
37 {
38 	TEST(prctl(PR_SET_TIMERSLACK, 200000));
39 	if (TST_RET != 0)
40 		tst_brk(TBROK | TTERRNO,
41 			"prctl set timerslack 200us failed");
42 }
43 
44 static struct tst_test test = {
45 	.setup = setup,
46 	.scall = "prctl()",
47 	.sample = sample_fn,
48 };
49