1//===-- xray_profile_collector.h -------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file is a part of XRay, a dynamic runtime instrumentation system.
10//
11// This file defines the interface for a data collection service, for XRay
12// profiling. What we implement here is an in-process service where
13// FunctionCallTrie instances can be handed off by threads, to be
14// consolidated/collected.
15//
16//===----------------------------------------------------------------------===//
17#ifndef XRAY_XRAY_PROFILE_COLLECTOR_H
18#define XRAY_XRAY_PROFILE_COLLECTOR_H
19
20#include "xray_function_call_trie.h"
21
22#include "xray/xray_log_interface.h"
23
24namespace __xray {
25
26/// The ProfileCollectorService implements a centralised mechanism for
27/// collecting FunctionCallTrie instances, indexed by thread ID. On demand, the
28/// ProfileCollectorService can be queried for the most recent state of the
29/// data, in a form that allows traversal.
30namespace profileCollectorService {
31
32/// Posts the FunctionCallTrie associated with a specific Thread ID. This
33/// will:
34///
35/// Moves the collection of FunctionCallTrie, Allocators, and Buffers associated
36/// with a thread's data to the queue. This takes ownership of the memory
37/// associated with a thread, and manages those exclusively.
38///
39void post(BufferQueue *Q, FunctionCallTrie &&T,
40 FunctionCallTrie::Allocators &&A,
41 FunctionCallTrie::Allocators::Buffers &&B, tid_t TId);
42
43/// The serialize will process all FunctionCallTrie instances in memory, and
44/// turn those into specifically formatted blocks, each describing the
45/// function call trie's contents in a compact form. In memory, this looks
46/// like the following layout:
47///
48/// - block size (32 bits)
49/// - block number (32 bits)
50/// - thread id (64 bits)
51/// - list of records:
52/// - function ids in leaf to root order, terminated by
53/// 0 (32 bits per function id)
54/// - call count (64 bit)
55/// - cumulative local time (64 bit)
56/// - record delimiter (64 bit, 0x0)
57///
58void serialize();
59
60/// The reset function will clear out any internal memory held by the
61/// service. The intent is to have the resetting be done in calls to the
62/// initialization routine, or explicitly through the flush log API.
63void reset();
64
65/// This nextBuffer function is meant to implement the iterator functionality,
66/// provided in the XRay API.
67XRayBuffer nextBuffer(XRayBuffer B);
68
69} // namespace profileCollectorService
70
71} // namespace __xray
72
73#endif // XRAY_XRAY_PROFILE_COLLECTOR_H
74