ebpf_exporter

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package kallsyms
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import (
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	"reflect"
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	"testing"
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)
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// kallsyms.txt is created from the stack below with the filter to wilt it down:
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//
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//   sudo cat /proc/kallsyms | grep -C3 -E ' (el0t_64_sync|el0t_64_sync_handler|el0_svc|do_el0_svc|invoke_syscall.constprop.0|__arm64_sys_execve|do_execveat_common|bprm_execve|load_elf_binary|begin_new_exec|mmput|__mmput|exit_mmap|unmap_vmas|unmap_page_range|mark_page_accessed|bpf_trampoline_6442507883.*|bpf_prog_.*_mark_page_accessed)$' > ksym/kallsyms.txt
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func TestStack(t *testing.T) {
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	stacks := [][]Addr{
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		{
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			{0xffffffc0801cee9c, "bpf_prog_9a4f2895a09f572a_mark_page_accessed\t[bpf]"},
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			{0xffffffc0801cee9c, "bpf_prog_9a4f2895a09f572a_mark_page_accessed\t[bpf]"},
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			{0xffffffc08012d06c, "bpf_trampoline_6442507883\t[bpf]"},
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			{0xffffffeb19cadfc8, "mark_page_accessed"},
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			{0xffffffeb19cf6148, "unmap_page_range"},
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			{0xffffffeb19cf6694, "unmap_vmas"},
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			{0xffffffeb19d04a60, "exit_mmap"},
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			{0xffffffeb19a8a5fc, "__mmput"},
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			{0xffffffeb19a8a7fc, "mmput"},
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			{0xffffffeb19d900e4, "begin_new_exec"},
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			{0xffffffeb19e06ba0, "load_elf_binary"},
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			{0xffffffeb19d8f17c, "bprm_execve"},
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			{0xffffffeb19d8f754, "do_execveat_common"},
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			{0xffffffeb19d8f83c, "__arm64_sys_execve"},
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			{0xffffffeb19a28a04, "invoke_syscall.constprop.0"},
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			{0xffffffeb19a28afc, "do_el0_svc"},
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			{0xffffffeb1a34d2d8, "el0_svc"},
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			{0xffffffeb1a34d768, "el0t_64_sync_handler"},
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			{0xffffffeb19a11558, "el0t_64_sync"},
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		},
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	}
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	d, err := NewDecoder("kallsyms.txt")
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	if err != nil {
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		t.Fatalf("Error creating ksym decoder: %v", err)
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	}
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	for i, stack := range stacks {
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		addrs := make([]uintptr, len(stack))
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		for j, addr := range stack {
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			addrs[j] = addr.Ptr
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		}
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		decoded := d.Stack(addrs)
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		if !reflect.DeepEqual(stack, decoded) {
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			t.Errorf("expected decoded stack %#v, got %#v", stack, decoded)
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			for j, addr := range stack {
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				if !reflect.DeepEqual(addr, decoded[j]) {
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					t.Errorf("Expected stack %d at position %d to be %#v, got %#v", i, j, addr, decoded[j])
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				}
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			}
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		}
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	}
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}
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func TestSymLookup(t *testing.T) {
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	addrs := []Addr{
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		{0xffffffeb19a8a478, ""},
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		{0xffffffeb19a8a480, "__pidfd_prepare"},
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		{0xffffffeb19a8a482, ""},
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		{0xffffffeb19cadfc0, "mark_page_accessed"},
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	}
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	d, err := NewDecoder("kallsyms.txt")
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	if err != nil {
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		t.Fatalf("Error creating ksym decoder: %v", err)
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	}
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	for _, addr := range addrs {
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		sym := d.Sym(addr.Ptr)
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		if sym != addr.Sym {
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			t.Errorf("Expected addr 0x%x to resolve to %q, got %q instead", addr.Ptr, addr.Sym, sym)
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		}
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	}
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}
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