1 //===-- TraceIntelPTGDBRemotePackets.cpp ------------------------*- 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 #include "lldb/Utility/TraceIntelPTGDBRemotePackets.h"
10 
11 using namespace llvm;
12 using namespace llvm::json;
13 
14 namespace lldb_private {
15 
16 const char *IntelPTDataKinds::kProcFsCpuInfo = "procfsCpuInfo";
17 const char *IntelPTDataKinds::kTraceBuffer = "traceBuffer";
18 
19 bool TraceIntelPTStartRequest::IsPerCoreTracing() const {
20   return per_core_tracing.getValueOr(false);
21 }
22 
23 bool fromJSON(const json::Value &value, TraceIntelPTStartRequest &packet,
24               Path path) {
25   ObjectMapper o(value, path);
26   if (!o || !fromJSON(value, (TraceStartRequest &)packet, path) ||
27       !o.map("enableTsc", packet.enable_tsc) ||
28       !o.map("psbPeriod", packet.psb_period) ||
29       !o.map("traceBufferSize", packet.trace_buffer_size))
30     return false;
31 
32   if (packet.IsProcessTracing()) {
33     if (!o.map("processBufferSizeLimit", packet.process_buffer_size_limit) ||
34         !o.map("perCoreTracing", packet.per_core_tracing))
35       return false;
36   }
37   return true;
38 }
39 
40 json::Value toJSON(const TraceIntelPTStartRequest &packet) {
41   json::Value base = toJSON((const TraceStartRequest &)packet);
42   json::Object &obj = *base.getAsObject();
43   obj.try_emplace("traceBufferSize", packet.trace_buffer_size);
44   obj.try_emplace("processBufferSizeLimit", packet.process_buffer_size_limit);
45   obj.try_emplace("psbPeriod", packet.psb_period);
46   obj.try_emplace("enableTsc", packet.enable_tsc);
47   obj.try_emplace("perCoreTracing", packet.per_core_tracing);
48   return base;
49 }
50 
51 std::chrono::nanoseconds
52 LinuxPerfZeroTscConversion::Convert(uint64_t raw_counter_value) {
53   uint64_t quot = raw_counter_value >> m_time_shift;
54   uint64_t rem_flag = (((uint64_t)1 << m_time_shift) - 1);
55   uint64_t rem = raw_counter_value & rem_flag;
56   return std::chrono::nanoseconds{m_time_zero + quot * m_time_mult +
57                                   ((rem * m_time_mult) >> m_time_shift)};
58 }
59 
60 json::Value LinuxPerfZeroTscConversion::toJSON() {
61   return json::Value(json::Object{
62       {"kind", "tsc-perf-zero-conversion"},
63       {"time_mult", m_time_mult},
64       {"time_shift", m_time_shift},
65       {"time_zero", m_time_zero},
66   });
67 }
68 
69 bool fromJSON(const json::Value &value, TraceTscConversionUP &tsc_conversion,
70               json::Path path) {
71   ObjectMapper o(value, path);
72 
73   uint64_t time_mult, time_shift, time_zero;
74   if (!o || !o.map("time_mult", time_mult) ||
75       !o.map("time_shift", time_shift) || !o.map("time_zero", time_zero))
76     return false;
77 
78   tsc_conversion = std::make_unique<LinuxPerfZeroTscConversion>(
79       static_cast<uint32_t>(time_mult), static_cast<uint16_t>(time_shift),
80       time_zero);
81 
82   return true;
83 }
84 
85 bool fromJSON(const json::Value &value, TraceIntelPTGetStateResponse &packet,
86               json::Path path) {
87   ObjectMapper o(value, path);
88   if (!o || !fromJSON(value, (TraceGetStateResponse &)packet, path))
89     return false;
90 
91   const Object &obj = *(value.getAsObject());
92   if (const json::Value *counters = obj.get("counters")) {
93     json::Path subpath = path.field("counters");
94     ObjectMapper ocounters(*counters, subpath);
95     if (!ocounters || !ocounters.mapOptional("tsc-perf-zero-conversion",
96                                              packet.tsc_conversion))
97       return false;
98   }
99   return true;
100 }
101 
102 json::Value toJSON(const TraceIntelPTGetStateResponse &packet) {
103   json::Value base = toJSON((const TraceGetStateResponse &)packet);
104 
105   if (packet.tsc_conversion) {
106     std::vector<json::Value> counters{};
107     base.getAsObject()->try_emplace(
108         "counters", json::Object{{"tsc-perf-zero-conversion",
109                                   packet.tsc_conversion->toJSON()}});
110   }
111 
112   return base;
113 }
114 
115 } // namespace lldb_private
116