xref: /aosp_15_r20/external/pigweed/pw_thread/snapshot.cc (revision 61c4878ac05f98d0ceed94b57d316916de578985)
1 // Copyright 2021 The Pigweed Authors
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not
4 // use this file except in compliance with the License. You may obtain a copy of
5 // the License at
6 //
7 //     https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12 // License for the specific language governing permissions and limitations under
13 // the License.
14 
15 #define PW_LOG_LEVEL PW_THREAD_CONFIG_LOG_LEVEL
16 
17 #include "pw_thread/snapshot.h"
18 
19 #include <cinttypes>
20 #include <string_view>
21 
22 #include "pw_bytes/span.h"
23 #include "pw_function/function.h"
24 #include "pw_log/log.h"
25 #include "pw_protobuf/encoder.h"
26 #include "pw_status/status.h"
27 #include "pw_thread/config.h"
28 #include "pw_thread_protos/thread.pwpb.h"
29 
30 namespace pw::thread {
31 
SnapshotStack(const StackContext & stack,proto::pwpb::Thread::StreamEncoder & encoder,const ProcessThreadStackCallback & thread_stack_callback)32 Status SnapshotStack(const StackContext& stack,
33                      proto::pwpb::Thread::StreamEncoder& encoder,
34                      const ProcessThreadStackCallback& thread_stack_callback) {
35   // TODO: b/234890430 - Add support for ascending stacks.
36   encoder.WriteStackStartPointer(stack.stack_high_addr).IgnoreError();
37   encoder.WriteStackEndPointer(stack.stack_low_addr).IgnoreError();
38   encoder.WriteStackPointer(stack.stack_pointer).IgnoreError();
39   // The PRIxPTR is an appropriate format specifier for hex uintptr_t values
40   // https://stackoverflow.com/a/5796039/1224002
41   PW_LOG_DEBUG("Active stack: 0x%08" PRIxPTR "-0x%08" PRIxPTR " (%ld bytes)",
42                stack.stack_high_addr,
43                stack.stack_pointer,
44                static_cast<long>(stack.stack_high_addr) -
45                    static_cast<long>(stack.stack_pointer));
46   if (stack.stack_pointer_est_peak.has_value()) {
47     const uintptr_t stack_pointer_est_peak =
48         stack.stack_pointer_est_peak.value();
49     encoder.WriteStackPointerEstPeak(stack_pointer_est_peak).IgnoreError();
50     PW_LOG_DEBUG("Est peak stack: 0x%08" PRIxPTR "-0x%08" PRIxPTR
51                  " (%ld bytes)",
52                  stack.stack_high_addr,
53                  stack_pointer_est_peak,
54                  static_cast<long>(stack.stack_high_addr) -
55                      static_cast<long>(stack_pointer_est_peak));
56   }
57   PW_LOG_DEBUG("Stack Limits: 0x%08" PRIxPTR "-0x%08" PRIxPTR " (%ld bytes)",
58                stack.stack_low_addr,
59                stack.stack_high_addr,
60                static_cast<long>(stack.stack_high_addr) -
61                    static_cast<long>(stack.stack_low_addr));
62 
63   if (stack.stack_pointer > stack.stack_high_addr) {
64     PW_LOG_ERROR("%s's stack underflowed by %lu bytes",
65                  stack.thread_name.data(),
66                  static_cast<long unsigned>(stack.stack_pointer -
67                                             stack.stack_high_addr));
68     return Status::OutOfRange();
69   }
70 
71   // Log an error, but don't prevent the capture.
72   if (stack.stack_pointer < stack.stack_low_addr) {
73     PW_LOG_ERROR(
74         "%s's stack overflowed by %lu bytes",
75         stack.thread_name.data(),
76         static_cast<long unsigned>(stack.stack_low_addr - stack.stack_pointer));
77   }
78 
79   return thread_stack_callback(
80       encoder,
81       ConstByteSpan(reinterpret_cast<const std::byte*>(stack.stack_pointer),
82                     stack.stack_high_addr - stack.stack_pointer));
83 }
84 
85 }  // namespace pw::thread
86