refactor: rename fifos to better names

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Nemo D'ACREMONT 2025-04-04 17:12:16 +02:00
parent e45992ac9d
commit 95d8b9939f
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2 changed files with 45 additions and 39 deletions

View File

@ -7,7 +7,6 @@
#include <sys/queue.h> #include <sys/queue.h>
#include <ucontext.h> #include <ucontext.h>
#include <valgrind/valgrind.h> #include <valgrind/valgrind.h>
#include <errno.h>
#define HAS_STATUS(entry, value) ((entry->status) & (value)) #define HAS_STATUS(entry, value) ((entry->status) & (value))
#define SET_STATUS(entry, value) ((entry->status) |= (value)) #define SET_STATUS(entry, value) ((entry->status) |= (value))
@ -43,8 +42,8 @@ static ucontext_t context_for_freeing;
struct last_thread_t; struct last_thread_t;
struct mutex_fifo_entry_t; struct mutex_fifo_entry_t;
struct context_entry { struct context_entry_t {
TAILQ_ENTRY(context_entry) TAILQ_ENTRY(context_entry_t)
link; // Use to navigate inside the list link; // Use to navigate inside the list
ucontext_t context; ucontext_t context;
void *retvalue; // return value or if the thread is waited, the id of the thread that wait for it void *retvalue; // return value or if the thread is waited, the id of the thread that wait for it
@ -55,27 +54,32 @@ struct context_entry {
char stack[STACK_SIZE]; char stack[STACK_SIZE];
}; };
// Current running thread
static struct context_entry_t* running = NULL;
TAILQ_HEAD(scheduler_fifo_t, context_entry_t);
static struct scheduler_fifo_t scheduler_fifo = TAILQ_HEAD_INITIALIZER(scheduler_fifo);
// Linked list used to store what's needed to be freed at the very end
TAILQ_HEAD(ctx_to_free_fifo_t, context_entry_t);
static struct ctx_to_free_fifo_t context_to_freed = TAILQ_HEAD_INITIALIZER(context_to_freed);
// Last thread_t types and fifo
// Used to optimize thread_join
struct last_thread_t { struct last_thread_t {
STAILQ_ENTRY(last_thread_t) STAILQ_ENTRY(last_thread_t)
link; link;
struct context_entry * last_thread; struct context_entry_t * last_thread;
int ref; // number of reference to this struct (for free) int ref; // number of reference to this struct (for free)
}; };
STAILQ_HEAD(last_thread_fifo_t, last_thread_t);
// Use TailQ from queue BSD struct last_thread_fifo_t last_thread_freed = STAILQ_HEAD_INITIALIZER(last_thread_freed);
static TAILQ_HEAD(context_head, context_entry) head = TAILQ_HEAD_INITIALIZER(head);
// Current running thread
static struct context_entry* running = NULL;
static TAILQ_HEAD(freed_context_head, context_entry) context_to_freed = TAILQ_HEAD_INITIALIZER(context_to_freed);
static STAILQ_HEAD(last_thread_head, last_thread_t) last_thread_freed = STAILQ_HEAD_INITIALIZER(last_thread_freed);
int thread_yield(void) int thread_yield(void)
{ {
//TRACE("thread_yield"); //TRACE("thread_yield");
if (TAILQ_EMPTY(&head)) { if (TAILQ_EMPTY(&scheduler_fifo)) {
return 0; return 0;
} }
@ -93,14 +97,16 @@ int thread_yield(void)
* check if the thread is not finished and is not waiting for a non finished thread * check if the thread is not finished and is not waiting for a non finished thread
* check if the thread is not the running one. * check if the thread is not the running one.
*/ */
struct context_entry* first = TAILQ_FIRST(&head); struct context_entry_t* first = TAILQ_FIRST(&scheduler_fifo);
TAILQ_REMOVE(&head, first, link); TAILQ_REMOVE(&scheduler_fifo, first, link);
if (!IS_FINISHED(running) && !IS_WAITING(running) && !IS_MUTEX_WAITING(running)) { if (!IS_FINISHED(running) && !IS_WAITING(running) && !IS_MUTEX_WAITING(running)) {
TAILQ_INSERT_TAIL(&head, running, link); TAILQ_INSERT_TAIL(&scheduler_fifo, running, link);
} }
TRACE("PICKING %p (previous was %p)", first, running); TRACE("PICKING %p (previous was %p)", first, running);
// Switch to the new thread. // Switch to the new thread.
struct context_entry* old_runner = running; struct context_entry_t* old_runner = running;
running = first; running = first;
swapcontext(&old_runner->context, &running->context); swapcontext(&old_runner->context, &running->context);
return 0; return 0;
@ -127,7 +133,7 @@ void thread_function_wrapper(void* (*func)(void*), void* funcarg)
int thread_create(thread_t* newthread, void* (*func)(void*), void* funcarg) int thread_create(thread_t* newthread, void* (*func)(void*), void* funcarg)
{ {
DBG("Create a new thread that execute function %p", func); DBG("Create a new thread that execute function %p", func);
struct context_entry* new_entry; struct context_entry_t* new_entry;
TRACE("Checking for previous allocated entry"); TRACE("Checking for previous allocated entry");
if (!TAILQ_EMPTY(&context_to_freed)) { if (!TAILQ_EMPTY(&context_to_freed)) {
new_entry = TAILQ_FIRST(&context_to_freed); new_entry = TAILQ_FIRST(&context_to_freed);
@ -160,14 +166,14 @@ int thread_create(thread_t* newthread, void* (*func)(void*), void* funcarg)
makecontext(&new_entry->context, (void (*)(void))thread_function_wrapper, 2, func, funcarg); makecontext(&new_entry->context, (void (*)(void))thread_function_wrapper, 2, func, funcarg);
#ifdef FIBO_STRAT #ifdef FIBO_STRAT
TAILQ_INSERT_HEAD(&head, new_entry, link); TAILQ_INSERT_HEAD(&scheduler_fifo, new_entry, link);
#else #else
TAILQ_INSERT_TAIL(&head, new_entry, link); TAILQ_INSERT_TAIL(&scheduler_fifo, new_entry, link);
#endif #endif
return 0; return 0;
} }
void print_entry(struct context_entry* entry) void print_entry(struct context_entry_t* entry)
{ {
TRACE("CONTEXT (%p, %p, %d);", entry, entry, WAS_ALLOCATED(entry)); TRACE("CONTEXT (%p, %p, %d);", entry, entry, WAS_ALLOCATED(entry));
} }
@ -175,7 +181,7 @@ void print_entry(struct context_entry* entry)
int thread_join(thread_t thread, void** retval) int thread_join(thread_t thread, void** retval)
{ {
TRACE("Join thread %p", thread); TRACE("Join thread %p", thread);
struct context_entry* entry = thread; struct context_entry_t* entry = thread;
// Check if the target is not already waited by another // Check if the target is not already waited by another
if (IS_WAITED(entry)) { if (IS_WAITED(entry)) {
return -1; return -1;
@ -234,8 +240,8 @@ int thread_join(thread_t thread, void** retval)
#ifdef FIBO_STRAT #ifdef FIBO_STRAT
#else #else
if (!IS_MUTEX_WAITING(GET_LAST_WAITED_THREAD(running))) { if (!IS_MUTEX_WAITING(GET_LAST_WAITED_THREAD(running))) {
TAILQ_REMOVE(&head, GET_LAST_WAITED_THREAD(running), link); TAILQ_REMOVE(&scheduler_fifo, GET_LAST_WAITED_THREAD(running), link);
TAILQ_INSERT_HEAD(&head, GET_LAST_WAITED_THREAD(running), link); TAILQ_INSERT_HEAD(&scheduler_fifo, GET_LAST_WAITED_THREAD(running), link);
} }
#endif #endif
do { do {
@ -280,16 +286,16 @@ void thread_exit(void* retval)
SET_STATUS(running, FINISHED); SET_STATUS(running, FINISHED);
if (IS_WAITED(running)) { if (IS_WAITED(running)) {
// If the thread was waited by another thread, we need to wake it up. // If the thread was waited by another thread, we need to wake it up.
struct context_entry* waited = running->retvalue; struct context_entry_t* waited = running->retvalue;
#ifdef FIBO_STRAT #ifdef FIBO_STRAT
TAILQ_INSERT_HEAD(&head, waited, link); TAILQ_INSERT_HEAD(&scheduler_fifo, waited, link);
#else #else
TAILQ_INSERT_TAIL(&head, waited, link); TAILQ_INSERT_TAIL(&scheduler_fifo, waited, link);
#endif #endif
} }
running->retvalue = retval; running->retvalue = retval;
if (!TAILQ_EMPTY(&head)) { if (!TAILQ_EMPTY(&scheduler_fifo)) {
thread_yield(); thread_yield();
} }
exit(0); exit(0);
@ -298,17 +304,17 @@ void thread_exit(void* retval)
void clear_context(void) void clear_context(void)
{ {
TRACE("INSIDE CLEAR"); TRACE("INSIDE CLEAR");
struct context_entry* last = NULL; struct context_entry_t* last = NULL;
// Loop over remaining threads to clean them from the heap. // Loop over remaining threads to clean them from the heap.
while (!TAILQ_EMPTY(&head)) { while (!TAILQ_EMPTY(&scheduler_fifo)) {
last = TAILQ_FIRST(&head); last = TAILQ_FIRST(&scheduler_fifo);
TAILQ_REMOVE(&head, last, link); TAILQ_REMOVE(&scheduler_fifo, last, link);
if (WAS_ALLOCATED(last)) { if (WAS_ALLOCATED(last)) {
VALGRIND_STACK_DEREGISTER(last->valgrind_id); VALGRIND_STACK_DEREGISTER(last->valgrind_id);
} }
if (IS_WAITED(last)) { if (IS_WAITED(last)) {
struct context_entry* waited = last->retvalue; struct context_entry_t* waited = last->retvalue;
TAILQ_INSERT_TAIL(&head, waited, link); TAILQ_INSERT_TAIL(&scheduler_fifo, waited, link);
} }
free(last); free(last);
} }
@ -336,7 +342,7 @@ void __attribute__((constructor)) setup_main_thread()
{ {
TRACE("premain"); TRACE("premain");
// Create an entry for the main thread. // Create an entry for the main thread.
struct context_entry* main = malloc(sizeof(*main)); struct context_entry_t* main = malloc(sizeof(*main));
// memset(main, 0, sizeof(*main)); // memset(main, 0, sizeof(*main));
getcontext(&main->context); getcontext(&main->context);
main->status = 0; main->status = 0;
@ -357,7 +363,7 @@ void __attribute__((destructor)) clear_last_thread()
{ {
TRACE("POST"); TRACE("POST");
// Running is the initial main thread. No need to switch to a static stack. // Running is the initial main thread. No need to switch to a static stack.
TAILQ_INSERT_HEAD(&head, running, link); TAILQ_INSERT_HEAD(&scheduler_fifo, running, link);
if (!WAS_ALLOCATED(running)) { if (!WAS_ALLOCATED(running)) {
clear_context(); clear_context();
exit(0); exit(0);
@ -409,7 +415,7 @@ int thread_mutex_unlock(thread_mutex_t* mutex)
STAILQ_REMOVE_HEAD(&mutex->fifo, link); STAILQ_REMOVE_HEAD(&mutex->fifo, link);
UNSET_STATUS(first->thread, MUTEX_WAITING); UNSET_STATUS(first->thread, MUTEX_WAITING);
TAILQ_INSERT_TAIL(&head, first->thread, link); TAILQ_INSERT_TAIL(&scheduler_fifo, first->thread, link);
} }
return mutex->dummy = 0; return mutex->dummy = 0;

View File

@ -43,7 +43,7 @@ extern void thread_exit(void *retval) __attribute__ ((__noreturn__));
/* Interface possible pour les mutex */ /* Interface possible pour les mutex */
struct mutex_fifo_entry_t { struct mutex_fifo_entry_t {
STAILQ_ENTRY(mutex_fifo_entry_t) link; STAILQ_ENTRY(mutex_fifo_entry_t) link;
struct context_entry* thread; struct context_entry_t* thread;
}; };
STAILQ_HEAD(mutex_fifo_t, mutex_fifo_entry_t); STAILQ_HEAD(mutex_fifo_t, mutex_fifo_entry_t);
typedef struct thread_mutex { int dummy; struct mutex_fifo_t fifo; } thread_mutex_t; typedef struct thread_mutex { int dummy; struct mutex_fifo_t fifo; } thread_mutex_t;