60 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| // Copyright (c) 2020 Facebook
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| #include "vmlinux.h"
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| #include <bpf/bpf_helpers.h>
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| 
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| #ifndef PERF_MAX_STACK_DEPTH
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| #define PERF_MAX_STACK_DEPTH         127
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| #endif
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| 
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| typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];
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| struct {
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| 	__uint(type, BPF_MAP_TYPE_STACK_TRACE);
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| 	__uint(max_entries, 16384);
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| 	__type(key, __u32);
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| 	__type(value, stack_trace_t);
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| } stackmap SEC(".maps");
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| 
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| struct {
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| 	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
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| 	__uint(max_entries, 1);
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| 	__type(key, __u32);
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| 	__type(value, stack_trace_t);
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| } stackdata_map SEC(".maps");
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| 
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| long stackid_kernel = 1;
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| long stackid_user = 1;
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| long stack_kernel = 1;
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| long stack_user = 1;
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| 
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| SEC("perf_event")
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| int oncpu(void *ctx)
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| {
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| 	stack_trace_t *trace;
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| 	__u32 key = 0;
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| 	long val;
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| 
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| 	val = bpf_get_stackid(ctx, &stackmap, 0);
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| 	if (val >= 0)
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| 		stackid_kernel = 2;
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| 	val = bpf_get_stackid(ctx, &stackmap, BPF_F_USER_STACK);
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| 	if (val >= 0)
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| 		stackid_user = 2;
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| 
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| 	trace = bpf_map_lookup_elem(&stackdata_map, &key);
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| 	if (!trace)
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| 		return 0;
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| 
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| 	val = bpf_get_stack(ctx, trace, sizeof(stack_trace_t), 0);
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| 	if (val > 0)
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| 		stack_kernel = 2;
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| 
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| 	val = bpf_get_stack(ctx, trace, sizeof(stack_trace_t), BPF_F_USER_STACK);
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| 	if (val > 0)
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| 		stack_user = 2;
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| 
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| 	return 0;
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| }
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| 
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| char LICENSE[] SEC("license") = "GPL";
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