gem5  v21.1.0.2
fiber.hh
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27 
28 #ifndef __BASE_FIBER_HH__
29 #define __BASE_FIBER_HH__
30 
31 // ucontext functions (like getcontext, setcontext etc) have been marked
32 // as deprecated and are hence hidden in latest macOS releases.
33 // By defining _XOPEN_SOURCE we make them available at compilation time.
34 #if defined(__APPLE__) && defined(__MACH__)
35 #define _XOPEN_SOURCE 600
36 #include <ucontext.h>
37 #undef _XOPEN_SOURCE
38 #else
39 #include <ucontext.h>
40 #endif
41 
42 // Avoid fortify source for longjmp to work between ucontext stacks.
43 #pragma push_macro("__USE_FORTIFY_LEVEL")
44 #undef __USE_FORTIFY_LEVEL
45 #include <setjmp.h>
46 #pragma pop_macro("__USE_FORTIFY_LEVEL")
47 
48 #include <cstddef>
49 #include <cstdint>
50 
51 #include "config/have_valgrind.hh"
52 
53 namespace gem5
54 {
55 
71 class Fiber
72 {
73  public:
77  const static size_t DefaultStackSize = 0x50000;
78 
87  Fiber(size_t stack_size=DefaultStackSize);
88  Fiber(Fiber *link, size_t stack_size=DefaultStackSize); // end of api_fiber
90 
94  virtual ~Fiber();
95 
102  void run();
103 
109  bool finished() const { return _finished; };
110 
116  bool started() const { return _started; };
117 
123  static Fiber *currentFiber();
124 
132  static Fiber *primaryFiber();
133 
134  protected:
140  virtual void main() = 0;
141 
142  void setStarted() { _started = true; }
143 
144  private:
145  static void entryTrampoline();
146  void start();
147 
148  ucontext_t ctx;
149  // ucontext is slow in swapcontext. Here we use _setjmp/_longjmp to avoid
150  // the additional signals for speed up.
151  jmp_buf jmp;
152 
154 
155  // The stack for this context, or a nullptr if allocated elsewhere.
156  void *stack;
157  size_t stackSize;
158  void *guardPage;
160 #if HAVE_VALGRIND
161  unsigned valgrindStackId;
162 #endif
163 
164  bool _started;
165  bool _finished;
166  void createContext();
167 };
168 
169 } // namespace gem5
170 
171 #endif // __BASE_FIBER_HH__
gem5::Fiber::guardPage
void * guardPage
Definition: fiber.hh:158
gem5::Fiber::run
void run()
Start executing the fiber represented by this object.
Definition: fiber.cc:166
gem5::Fiber::ctx
ucontext_t ctx
Definition: fiber.hh:148
gem5::Fiber::guardPageSize
size_t guardPageSize
Definition: fiber.hh:159
gem5::Fiber::setStarted
void setStarted()
Definition: fiber.hh:142
gem5::Fiber::createContext
void createContext()
Definition: fiber.cc:123
gem5::Fiber::~Fiber
virtual ~Fiber()
Definition: fiber.cc:112
gem5::Fiber::currentFiber
static Fiber * currentFiber()
Get a pointer to the current running Fiber.
Definition: fiber.cc:185
gem5::Fiber::main
virtual void main()=0
This method is called when this fiber is first run.
gem5::Fiber::start
void start()
Definition: fiber.cc:142
gem5::Fiber::DefaultStackSize
const static size_t DefaultStackSize
Definition: fiber.hh:77
gem5::Fiber::primaryFiber
static Fiber * primaryFiber()
Get a pointer to the primary Fiber.
Definition: fiber.cc:186
gem5::Fiber::jmp
jmp_buf jmp
Definition: fiber.hh:151
gem5::Fiber::_finished
bool _finished
Definition: fiber.hh:165
gem5::Fiber::_started
bool _started
Definition: fiber.hh:164
gem5::Fiber
This class represents a fiber, which is a light weight sort of thread which is cooperatively schedule...
Definition: fiber.hh:71
gem5::Fiber::stackSize
size_t stackSize
Definition: fiber.hh:157
gem5::Fiber::started
bool started() const
Returns whether the "main" function of this fiber has started.
Definition: fiber.hh:116
gem5::Fiber::entryTrampoline
static void entryTrampoline()
Definition: fiber.cc:80
gem5::Fiber::finished
bool finished() const
Returns whether the "main" function of this fiber has finished.
Definition: fiber.hh:109
gem5::Fiber::Fiber
Fiber(size_t stack_size=DefaultStackSize)
Definition: fiber.cc:85
gem5::Fiber::stack
void * stack
Definition: fiber.hh:156
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
gem5::Fiber::link
Fiber * link
Definition: fiber.hh:153

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