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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */3#include <vmlinux.h>4#include <bpf/bpf_helpers.h>5#include <bpf/bpf_tracing.h>6#include <bpf/usdt.bpf.h>7 8char _license[] SEC("license") = "GPL";9 10__u64 entry_stack1[32], exit_stack1[32];11__u64 entry_stack1_recur[32], exit_stack1_recur[32];12__u64 entry_stack2[32];13__u64 entry_stack3[32];14__u64 entry_stack4[32], exit_stack4[32];15__u64 usdt_stack[32];16 17int entry1_len, exit1_len;18int entry1_recur_len, exit1_recur_len;19int entry2_len, exit2_len;20int entry3_len, exit3_len;21int entry4_len, exit4_len;22int usdt_len;23 24#define SZ sizeof(usdt_stack)25 26SEC("uprobe//proc/self/exe:target_1")27int BPF_UPROBE(uprobe_1)28{29 /* target_1 is recursive wit depth of 2, so we capture two separate30 * stack traces, depending on which occurence it is31 */32 static bool recur = false;33 34 if (!recur)35 entry1_len = bpf_get_stack(ctx, &entry_stack1, SZ, BPF_F_USER_STACK);36 else37 entry1_recur_len = bpf_get_stack(ctx, &entry_stack1_recur, SZ, BPF_F_USER_STACK);38 39 recur = true;40 return 0;41}42 43SEC("uretprobe//proc/self/exe:target_1")44int BPF_URETPROBE(uretprobe_1)45{46 /* see above, target_1 is recursive */47 static bool recur = false;48 49 /* NOTE: order of returns is reversed to order of entries */50 if (!recur)51 exit1_recur_len = bpf_get_stack(ctx, &exit_stack1_recur, SZ, BPF_F_USER_STACK);52 else53 exit1_len = bpf_get_stack(ctx, &exit_stack1, SZ, BPF_F_USER_STACK);54 55 recur = true;56 return 0;57}58 59SEC("uprobe//proc/self/exe:target_2")60int BPF_UPROBE(uprobe_2)61{62 entry2_len = bpf_get_stack(ctx, &entry_stack2, SZ, BPF_F_USER_STACK);63 return 0;64}65 66/* no uretprobe for target_2 */67 68SEC("uprobe//proc/self/exe:target_3")69int BPF_UPROBE(uprobe_3)70{71 entry3_len = bpf_get_stack(ctx, &entry_stack3, SZ, BPF_F_USER_STACK);72 return 0;73}74 75/* no uretprobe for target_3 */76 77SEC("uprobe//proc/self/exe:target_4")78int BPF_UPROBE(uprobe_4)79{80 entry4_len = bpf_get_stack(ctx, &entry_stack4, SZ, BPF_F_USER_STACK);81 return 0;82}83 84SEC("uretprobe//proc/self/exe:target_4")85int BPF_URETPROBE(uretprobe_4)86{87 exit4_len = bpf_get_stack(ctx, &exit_stack4, SZ, BPF_F_USER_STACK);88 return 0;89}90 91SEC("usdt//proc/self/exe:uretprobe_stack:target")92int BPF_USDT(usdt_probe)93{94 usdt_len = bpf_get_stack(ctx, &usdt_stack, SZ, BPF_F_USER_STACK);95 return 0;96}97