xref: /OK3568_Linux_fs/kernel/tools/testing/selftests/bpf/progs/loop1.c (revision 4882a59341e53eb6f0b4789bf948001014eff981) 
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun // Copyright (c) 2019 Facebook
3*4882a593Smuzhiyun #include <linux/sched.h>
4*4882a593Smuzhiyun #include <linux/ptrace.h>
5*4882a593Smuzhiyun #include <stdint.h>
6*4882a593Smuzhiyun #include <stddef.h>
7*4882a593Smuzhiyun #include <stdbool.h>
8*4882a593Smuzhiyun #include <linux/bpf.h>
9*4882a593Smuzhiyun #include <bpf/bpf_helpers.h>
10*4882a593Smuzhiyun #include <bpf/bpf_tracing.h>
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun char _license[] SEC("license") = "GPL";
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun SEC("raw_tracepoint/kfree_skb")
nested_loops(volatile struct pt_regs * ctx)15*4882a593Smuzhiyun int nested_loops(volatile struct pt_regs* ctx)
16*4882a593Smuzhiyun {
17*4882a593Smuzhiyun 	int i, j, sum = 0, m;
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun 	for (j = 0; j < 300; j++)
20*4882a593Smuzhiyun 		for (i = 0; i < j; i++) {
21*4882a593Smuzhiyun 			if (j & 1)
22*4882a593Smuzhiyun 				m = PT_REGS_RC(ctx);
23*4882a593Smuzhiyun 			else
24*4882a593Smuzhiyun 				m = j;
25*4882a593Smuzhiyun 			sum += i * m;
26*4882a593Smuzhiyun 		}
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 	return sum;
29*4882a593Smuzhiyun }
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