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 fromJSON(const json::Value &value, TraceIntelPTStartRequest &packet,
20               Path path) {
21   ObjectMapper o(value, path);
22   if (!o || !fromJSON(value, (TraceStartRequest &)packet, path) ||
23       !o.map("enableTsc", packet.enable_tsc) ||
24       !o.map("psbPeriod", packet.psb_period) ||
25       !o.map("traceBufferSize", packet.trace_buffer_size))
26     return false;
27 
28   if (packet.IsProcessTracing()) {
29     if (!o.map("processBufferSizeLimit", packet.process_buffer_size_limit) ||
30         !o.map("perCoreTracing", packet.per_core_tracing))
31       return false;
32   }
33   return true;
34 }
35 
36 json::Value toJSON(const TraceIntelPTStartRequest &packet) {
37   json::Value base = toJSON((const TraceStartRequest &)packet);
38   json::Object &obj = *base.getAsObject();
39   obj.try_emplace("traceBufferSize", packet.trace_buffer_size);
40   obj.try_emplace("processBufferSizeLimit", packet.process_buffer_size_limit);
41   obj.try_emplace("psbPeriod", packet.psb_period);
42   obj.try_emplace("enableTsc", packet.enable_tsc);
43   obj.try_emplace("perCoreTracing", packet.per_core_tracing);
44   return base;
45 }
46 
47 std::chrono::nanoseconds
48 LinuxPerfZeroTscConversion::Convert(uint64_t raw_counter_value) {
49   uint64_t quot = raw_counter_value >> m_time_shift;
50   uint64_t rem_flag = (((uint64_t)1 << m_time_shift) - 1);
51   uint64_t rem = raw_counter_value & rem_flag;
52   return std::chrono::nanoseconds{m_time_zero + quot * m_time_mult +
53                                   ((rem * m_time_mult) >> m_time_shift)};
54 }
55 
56 json::Value LinuxPerfZeroTscConversion::toJSON() {
57   return json::Value(json::Object{
58       {"kind", "tsc-perf-zero-conversion"},
59       {"time_mult", static_cast<int64_t>(m_time_mult)},
60       {"time_shift", static_cast<int64_t>(m_time_shift)},
61       {"time_zero", static_cast<int64_t>(m_time_zero)},
62   });
63 }
64 
65 bool fromJSON(const json::Value &value, TraceTscConversionUP &tsc_conversion,
66               json::Path path) {
67   ObjectMapper o(value, path);
68 
69   int64_t time_mult, time_shift, time_zero;
70   if (!o || !o.map("time_mult", time_mult) ||
71       !o.map("time_shift", time_shift) || !o.map("time_zero", time_zero))
72     return false;
73 
74   tsc_conversion = std::make_unique<LinuxPerfZeroTscConversion>(
75       static_cast<uint32_t>(time_mult), static_cast<uint16_t>(time_shift),
76       static_cast<uint64_t>(time_zero));
77 
78   return true;
79 }
80 
81 bool fromJSON(const json::Value &value, TraceIntelPTGetStateResponse &packet,
82               json::Path path) {
83   ObjectMapper o(value, path);
84   if (!o || !fromJSON(value, (TraceGetStateResponse &)packet, path))
85     return false;
86 
87   const Object &obj = *(value.getAsObject());
88   if (const json::Value *counters = obj.get("counters")) {
89     json::Path subpath = path.field("counters");
90     ObjectMapper ocounters(*counters, subpath);
91     if (!ocounters || !ocounters.mapOptional("tsc-perf-zero-conversion",
92                                              packet.tsc_conversion))
93       return false;
94   }
95   return true;
96 }
97 
98 json::Value toJSON(const TraceIntelPTGetStateResponse &packet) {
99   json::Value base = toJSON((const TraceGetStateResponse &)packet);
100 
101   if (packet.tsc_conversion) {
102     std::vector<json::Value> counters{};
103     base.getAsObject()->try_emplace(
104         "counters", json::Object{{"tsc-perf-zero-conversion",
105                                   packet.tsc_conversion->toJSON()}});
106   }
107 
108   return base;
109 }
110 
111 } // namespace lldb_private
112