• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // Copyright 2020 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 #pragma once
15 
16 #include "FreeRTOS.h"
17 #include "pw_assert/assert.h"
18 #include "pw_thread/thread.h"
19 #include "pw_thread_freertos/config.h"
20 #include "pw_thread_freertos/context.h"
21 #include "task.h"
22 
23 namespace pw::thread::freertos {
24 
25 // pw::thread::Options for FreeRTOS.
26 //
27 // Example usage:
28 //
29 //   // Uses the default stack size and priority, but specifies a custom name.
30 //   pw::thread::Thread example_thread(
31 //     pw::thread::freertos::Options()
32 //         .set_name("example_thread"),
33 //     example_thread_function);
34 //
35 //   // Provides the name, priority, and pre-allocated context.
36 //   pw::thread::Thread static_example_thread(
37 //     pw::thread::freertos::Options()
38 //         .set_name("static_example_thread")
39 //         .set_priority(kFooPriority)
40 //         .set_static_context(static_example_thread_context),
41 //     example_thread_function);
42 //
43 class Options : public thread::Options {
44  public:
45   constexpr Options() = default;
46   constexpr Options(const Options&) = default;
47   constexpr Options(Options&& other) = default;
48 
49   // Sets the name for the FreeRTOS task, note that this will be truncated
50   // based on configMAX_TASK_NAME_LEN.
51   // This is deep copied by FreeRTOS into the task's task control block (TCB).
set_name(const char * name)52   constexpr Options& set_name(const char* name) {
53     name_ = name;
54     return *this;
55   }
56 
57   // Sets the priority for the FreeRTOS task. This must be a value between
58   // 0 to PW_THREAD_FREERTOS_CONFIG_MAXIMUM_PRIORITY. Higher priority
59   // values have a higher priority.
60   //
61   // Note that the idle task priority, tskIDLE_PRIORITY, is fixed to 0.
62   // See the FreeRTOS documentation on the idle task for more details.
63   //
64   // Precondition: This must be <= PW_THREAD_FREERTOS_CONFIG_MAXIMUM_PRIORITY.
set_priority(UBaseType_t priority)65   constexpr Options& set_priority(UBaseType_t priority) {
66     PW_DASSERT(priority <= config::kMaximumPriority);
67     priority_ = priority;
68     return *this;
69   }
70 
71 #if PW_THREAD_FREERTOS_CONFIG_DYNAMIC_ALLOCATION_ENABLED
72   // Set the stack size of dynamic thread allocations.
73   //
74   // Precondition: size_words must be >= configMINIMAL_STACK_SIZE
set_stack_size(size_t size_words)75   constexpr Options& set_stack_size(size_t size_words) {
76     PW_DASSERT(size_words >= config::kMinimumStackSizeWords);
77     stack_size_words_ = size_words;
78     return *this;
79   }
80 #endif  // PW_THREAD_FREERTOS_CONFIG_DYNAMIC_ALLOCATION_ENABLED
81 
82   // Set the pre-allocated context (all memory needed to run a thread), see the
83   // pw::thread::freertos::StaticContext for more detail.
set_static_context(StaticContext & context)84   constexpr Options& set_static_context(StaticContext& context) {
85     context_ = &context;
86     return *this;
87   }
88 
89  private:
90   friend thread::Thread;
91   // FreeRTOS requires a valid name when asserts are enabled,
92   // configMAX_TASK_NAME_LEN may be as small as one character.
93   static constexpr char kDefaultName[] = "pw::Thread";
94 
name()95   const char* name() const { return name_; }
priority()96   UBaseType_t priority() const { return priority_; }
97 #if PW_THREAD_FREERTOS_CONFIG_DYNAMIC_ALLOCATION_ENABLED
stack_size_words()98   size_t stack_size_words() const { return stack_size_words_; }
99 #endif  // PW_THREAD_FREERTOS_CONFIG_DYNAMIC_ALLOCATION_ENABLED
static_context()100   StaticContext* static_context() const { return context_; }
101 
102   const char* name_ = kDefaultName;
103   UBaseType_t priority_ = config::kDefaultPriority;
104 #if PW_THREAD_FREERTOS_CONFIG_DYNAMIC_ALLOCATION_ENABLED
105   size_t stack_size_words_ = config::kDefaultStackSizeWords;
106 #endif  // PW_THREAD_FREERTOS_CONFIG_DYNAMIC_ALLOCATION_ENABLED
107   StaticContext* context_ = nullptr;
108 };
109 
110 }  // namespace pw::thread::freertos
111