| 34,7 → 34,7 |
|---|
| */ |
| |
| #include <libadt/list.h> |
| #include <psthread.h> |
| #include <fibril.h> |
| #include <malloc.h> |
| #include <unistd.h> |
| #include <thread.h> |
| 44,8 → 44,8 |
|---|
| #include <assert.h> |
| #include <async.h> |
| |
| #ifndef PSTHREAD_INITIAL_STACK_PAGES_NO |
| #define PSTHREAD_INITIAL_STACK_PAGES_NO 1 |
| #ifndef FIBRIL_INITIAL_STACK_PAGES_NO |
| #define FIBRIL_INITIAL_STACK_PAGES_NO 1 |
| #endif |
| |
| static LIST_INITIALIZE(ready_list); |
| 52,20 → 52,20 |
|---|
| static LIST_INITIALIZE(serialized_list); |
| static LIST_INITIALIZE(manager_list); |
| |
| static void psthread_main(void); |
| static void fibril_main(void); |
| |
| static atomic_t psthread_futex = FUTEX_INITIALIZER; |
| /** Count of real threads that are in async_serialized mode */ |
| static atomic_t fibril_futex = FUTEX_INITIALIZER; |
| /** Number of threads that are in async_serialized mode */ |
| static int serialized_threads; /* Protected by async_futex */ |
| /** Thread-local count of serialization. If >0, we must not preempt */ |
| static __thread int serialization_count; |
| /** Counter of threads residing in async_manager */ |
| static int threads_in_manager; |
| /** Counter for fibrils residing in async_manager */ |
| static int fibrils_in_manager; |
| |
| /** Setup psthread information into TCB structure */ |
| psthread_data_t *psthread_setup(void) |
| /** Setup fibril information into TCB structure */ |
| fibril_t *fibril_setup(void) |
| { |
| psthread_data_t *pt; |
| fibril_t *f; |
| tcb_t *tcb; |
| |
| tcb = __make_tls(); |
| 72,76 → 72,75 |
|---|
| if (!tcb) |
| return NULL; |
| |
| pt = malloc(sizeof(*pt)); |
| if (!pt) { |
| f = malloc(sizeof(*f)); |
| if (!f) { |
| __free_tls(tcb); |
| return NULL; |
| } |
| |
| tcb->pst_data = pt; |
| pt->tcb = tcb; |
| tcb->fibril_data = f; |
| f->tcb = tcb; |
| |
| return pt; |
| return f; |
| } |
| |
| void psthread_teardown(psthread_data_t *pt) |
| void fibril_teardown(fibril_t *f) |
| { |
| __free_tls(pt->tcb); |
| free(pt); |
| __free_tls(f->tcb); |
| free(f); |
| } |
| |
| /** Function that spans the whole life-cycle of a pseudo thread. |
| /** Function that spans the whole life-cycle of a fibril. |
| * |
| * Each pseudo thread begins execution in this function. |
| * Then the function implementing the pseudo thread logic is called. |
| * After its return, the return value is saved for a potentional |
| * joiner. If the joiner exists, it is woken up. The pseudo thread |
| * then switches to another pseudo thread, which cleans up after it. |
| * Each fibril begins execution in this function. Then the function |
| * implementing the fibril logic is called. After its return, the return value |
| * is saved for a potentional joiner. If the joiner exists, it is woken up. The |
| * fibril then switches to another fibril, which cleans up after it. |
| */ |
| void psthread_main(void) |
| void fibril_main(void) |
| { |
| psthread_data_t *pt = __tcb_get()->pst_data; |
| fibril_t *f = __tcb_get()->fibril_data; |
| |
| pt->retval = pt->func(pt->arg); |
| f->retval = f->func(f->arg); |
| |
| /* |
| * If there is a joiner, wake it up and save our return value. |
| */ |
| if (pt->joiner) { |
| list_append(&pt->joiner->link, &ready_list); |
| pt->joiner->joinee_retval = pt->retval; |
| if (f->joiner) { |
| list_append(&f->joiner->link, &ready_list); |
| f->joiner->joinee_retval = f->retval; |
| } |
| |
| psthread_schedule_next_adv(PS_FROM_DEAD); |
| fibril_schedule_next_adv(FIBRIL_FROM_DEAD); |
| /* not reached */ |
| } |
| |
| /** Schedule next userspace pseudo thread. |
| /** Schedule next fibril. |
| * |
| * If calling with PS_TO_MANAGER parameter, the async_futex should be |
| * If calling with FIBRIL_TO_MANAGER parameter, the async_futex should be |
| * held. |
| * |
| * @param ctype One of PS_SLEEP, PS_PREEMPT, PS_TO_MANAGER, |
| * PS_FROM_MANAGER, PS_FROM_DEAD. The parameter describes |
| * the circumstances of the switch. |
| * @return Return 0 if there is no ready pseudo thread, |
| * @param stype One of FIBRIL_SLEEP, FIBRIL_PREEMPT, FIBRIL_TO_MANAGER, |
| * FIBRIL_FROM_MANAGER, FIBRIL_FROM_DEAD. The parameter |
| * describes the circumstances of the switch. |
| * @return Return 0 if there is no ready fibril, |
| * return 1 otherwise. |
| */ |
| int psthread_schedule_next_adv(pschange_type ctype) |
| int fibril_schedule_next_adv(fibril_switch_type_t stype) |
| { |
| psthread_data_t *srcpt, *dstpt; |
| fibril_t *srcf, *dstf; |
| int retval = 0; |
| |
| futex_down(&psthread_futex); |
| futex_down(&fibril_futex); |
| |
| if (ctype == PS_PREEMPT && list_empty(&ready_list)) |
| if (stype == FIBRIL_PREEMPT && list_empty(&ready_list)) |
| goto ret_0; |
| if (ctype == PS_SLEEP) { |
| if (stype == FIBRIL_SLEEP) { |
| if (list_empty(&ready_list) && list_empty(&serialized_list)) |
| goto ret_0; |
| } |
| |
| if (ctype == PS_FROM_MANAGER) { |
| if (stype == FIBRIL_FROM_MANAGER) { |
| if (list_empty(&ready_list) && list_empty(&serialized_list)) |
| goto ret_0; |
| /* |
| 148,113 → 147,112 |
|---|
| * Do not preempt if there is not sufficient count of thread |
| * managers. |
| */ |
| if (list_empty(&serialized_list) && threads_in_manager <= |
| if (list_empty(&serialized_list) && fibrils_in_manager <= |
| serialized_threads) { |
| goto ret_0; |
| } |
| } |
| /* If we are going to manager and none exists, create it */ |
| if (ctype == PS_TO_MANAGER || ctype == PS_FROM_DEAD) { |
| if (stype == FIBRIL_TO_MANAGER || stype == FIBRIL_FROM_DEAD) { |
| while (list_empty(&manager_list)) { |
| futex_up(&psthread_futex); |
| futex_up(&fibril_futex); |
| async_create_manager(); |
| futex_down(&psthread_futex); |
| futex_down(&fibril_futex); |
| } |
| } |
| |
| srcpt = __tcb_get()->pst_data; |
| if (ctype != PS_FROM_DEAD) { |
| srcf = __tcb_get()->fibril_data; |
| if (stype != FIBRIL_FROM_DEAD) { |
| /* Save current state */ |
| if (!context_save(&srcpt->ctx)) { |
| if (!context_save(&srcf->ctx)) { |
| if (serialization_count) |
| srcpt->flags &= ~PSTHREAD_SERIALIZED; |
| if (srcpt->clean_after_me) { |
| srcf->flags &= ~FIBRIL_SERIALIZED; |
| if (srcf->clean_after_me) { |
| /* |
| * Cleanup after the dead pseudo thread from |
| * which we restored context here. |
| * Cleanup after the dead fibril from which we |
| * restored context here. |
| */ |
| free(srcpt->clean_after_me->stack); |
| psthread_teardown(srcpt->clean_after_me); |
| srcpt->clean_after_me = NULL; |
| free(srcf->clean_after_me->stack); |
| fibril_teardown(srcf->clean_after_me); |
| srcf->clean_after_me = NULL; |
| } |
| return 1; /* futex_up already done here */ |
| } |
| |
| /* Save myself to the correct run list */ |
| if (ctype == PS_PREEMPT) |
| list_append(&srcpt->link, &ready_list); |
| else if (ctype == PS_FROM_MANAGER) { |
| list_append(&srcpt->link, &manager_list); |
| threads_in_manager--; |
| if (stype == FIBRIL_PREEMPT) |
| list_append(&srcf->link, &ready_list); |
| else if (stype == FIBRIL_FROM_MANAGER) { |
| list_append(&srcf->link, &manager_list); |
| fibrils_in_manager--; |
| } else { |
| /* |
| * If ctype == PS_TO_MANAGER, don't save ourselves to |
| * If stype == FIBRIL_TO_MANAGER, don't put ourselves to |
| * any list, we should already be somewhere, or we will |
| * be lost. |
| * |
| * The ctype == PS_SLEEP case is similar. The pseudo |
| * thread has an external refernce which can be used to |
| * wake it up once that time has come. |
| * The stype == FIBRIL_SLEEP case is similar. The fibril |
| * has an external refernce which can be used to wake it |
| * up once that time has come. |
| */ |
| } |
| } |
| |
| /* Choose new thread to run */ |
| if (ctype == PS_TO_MANAGER || ctype == PS_FROM_DEAD) { |
| dstpt = list_get_instance(manager_list.next, psthread_data_t, |
| link); |
| if (serialization_count && ctype == PS_TO_MANAGER) { |
| /* Choose a new fibril to run */ |
| if (stype == FIBRIL_TO_MANAGER || stype == FIBRIL_FROM_DEAD) { |
| dstf = list_get_instance(manager_list.next, fibril_t, link); |
| if (serialization_count && stype == FIBRIL_TO_MANAGER) { |
| serialized_threads++; |
| srcpt->flags |= PSTHREAD_SERIALIZED; |
| srcf->flags |= FIBRIL_SERIALIZED; |
| } |
| threads_in_manager++; |
| fibrils_in_manager++; |
| |
| if (ctype == PS_FROM_DEAD) |
| dstpt->clean_after_me = srcpt; |
| if (stype == FIBRIL_FROM_DEAD) |
| dstf->clean_after_me = srcf; |
| } else { |
| if (!list_empty(&serialized_list)) { |
| dstpt = list_get_instance(serialized_list.next, |
| psthread_data_t, link); |
| dstf = list_get_instance(serialized_list.next, fibril_t, |
| link); |
| serialized_threads--; |
| } else { |
| dstpt = list_get_instance(ready_list.next, |
| psthread_data_t, link); |
| dstf = list_get_instance(ready_list.next, fibril_t, |
| link); |
| } |
| } |
| list_remove(&dstpt->link); |
| list_remove(&dstf->link); |
| |
| futex_up(&psthread_futex); |
| context_restore(&dstpt->ctx); |
| futex_up(&fibril_futex); |
| context_restore(&dstf->ctx); |
| /* not reached */ |
| |
| ret_0: |
| futex_up(&psthread_futex); |
| futex_up(&fibril_futex); |
| return retval; |
| } |
| |
| /** Wait for uspace pseudo thread to finish. |
| /** Wait for fibril to finish. |
| * |
| * Each pseudo thread can be only joined by one other pseudo thread. Moreover, |
| * the joiner must be from the same thread as the joinee. |
| * Each fibril can be only joined by one other fibril. Moreover, the joiner must |
| * be from the same thread as the joinee. |
| * |
| * @param psthrid Pseudo thread to join. |
| * @param fid Fibril to join. |
| * |
| * @return Value returned by the finished thread. |
| * @return Value returned by the completed fibril. |
| */ |
| int psthread_join(pstid_t psthrid) |
| int fibril_join(fid_t fid) |
| { |
| psthread_data_t *pt; |
| psthread_data_t *cur; |
| fibril_t *f; |
| fibril_t *cur; |
| |
| /* Handle psthrid = Kernel address -> it is wait for call */ |
| pt = (psthread_data_t *) psthrid; |
| /* Handle fid = Kernel address -> it is wait for call */ |
| f = (fibril_t *) fid; |
| |
| /* |
| * The joiner is running so the joinee isn't. |
| */ |
| cur = __tcb_get()->pst_data; |
| pt->joiner = cur; |
| psthread_schedule_next_adv(PS_SLEEP); |
| cur = __tcb_get()->fibril_data; |
| f->joiner = cur; |
| fibril_schedule_next_adv(FIBRIL_SLEEP); |
| |
| /* |
| * The joinee fills in the return value. |
| 262,113 → 260,111 |
|---|
| return cur->joinee_retval; |
| } |
| |
| /** Create a userspace pseudo thread. |
| /** Create a new fibril. |
| * |
| * @param func Pseudo thread function. |
| * @param func Implementing function of the new fibril. |
| * @param arg Argument to pass to func. |
| * |
| * @return Return 0 on failure or TLS of the new pseudo thread. |
| * @return Return 0 on failure or TLS of the new fibril. |
| */ |
| pstid_t psthread_create(int (*func)(void *), void *arg) |
| fid_t fibril_create(int (*func)(void *), void *arg) |
| { |
| psthread_data_t *pt; |
| fibril_t *f; |
| |
| pt = psthread_setup(); |
| if (!pt) |
| f = fibril_setup(); |
| if (!f) |
| return 0; |
| pt->stack = (char *) malloc(PSTHREAD_INITIAL_STACK_PAGES_NO * |
| f->stack = (char *) malloc(FIBRIL_INITIAL_STACK_PAGES_NO * |
| getpagesize()); |
| |
| if (!pt->stack) { |
| psthread_teardown(pt); |
| if (!f->stack) { |
| fibril_teardown(f); |
| return 0; |
| } |
| |
| pt->arg= arg; |
| pt->func = func; |
| pt->clean_after_me = NULL; |
| pt->joiner = NULL; |
| pt->joinee_retval = 0; |
| pt->retval = 0; |
| pt->flags = 0; |
| f->arg = arg; |
| f->func = func; |
| f->clean_after_me = NULL; |
| f->joiner = NULL; |
| f->joinee_retval = 0; |
| f->retval = 0; |
| f->flags = 0; |
| |
| context_save(&pt->ctx); |
| context_set(&pt->ctx, FADDR(psthread_main), pt->stack, |
| PSTHREAD_INITIAL_STACK_PAGES_NO * getpagesize(), pt->tcb); |
| context_save(&f->ctx); |
| context_set(&f->ctx, FADDR(fibril_main), f->stack, |
| FIBRIL_INITIAL_STACK_PAGES_NO * getpagesize(), f->tcb); |
| |
| return (pstid_t) pt; |
| return (fid_t) f; |
| } |
| |
| /** Add a thread to the ready list. |
| /** Add a fibril to the ready list. |
| * |
| * @param psthrid Pinter to the pseudo thread structure of the |
| * pseudo thread to be added. |
| * @param fid Pinter to the fibril structure of the fibril to be added. |
| */ |
| void psthread_add_ready(pstid_t psthrid) |
| void fibril_add_ready(fid_t fid) |
| { |
| psthread_data_t *pt; |
| fibril_t *f; |
| |
| pt = (psthread_data_t *) psthrid; |
| futex_down(&psthread_futex); |
| if ((pt->flags & PSTHREAD_SERIALIZED)) |
| list_append(&pt->link, &serialized_list); |
| f = (fibril_t *) fid; |
| futex_down(&fibril_futex); |
| if ((f->flags & FIBRIL_SERIALIZED)) |
| list_append(&f->link, &serialized_list); |
| else |
| list_append(&pt->link, &ready_list); |
| futex_up(&psthread_futex); |
| list_append(&f->link, &ready_list); |
| futex_up(&fibril_futex); |
| } |
| |
| /** Add a pseudo thread to the manager list. |
| /** Add a fibril to the manager list. |
| * |
| * @param psthrid Pinter to the pseudo thread structure of the |
| * pseudo thread to be added. |
| * @param fid Pinter to the fibril structure of the fibril to be added. |
| */ |
| void psthread_add_manager(pstid_t psthrid) |
| void fibril_add_manager(fid_t fid) |
| { |
| psthread_data_t *pt; |
| fibril_t *f; |
| |
| pt = (psthread_data_t *) psthrid; |
| f = (fibril_t *) fid; |
| |
| futex_down(&psthread_futex); |
| list_append(&pt->link, &manager_list); |
| futex_up(&psthread_futex); |
| futex_down(&fibril_futex); |
| list_append(&f->link, &manager_list); |
| futex_up(&fibril_futex); |
| } |
| |
| /** Remove one manager from manager list */ |
| void psthread_remove_manager(void) |
| /** Remove one manager from the manager list. */ |
| void fibril_remove_manager(void) |
| { |
| futex_down(&psthread_futex); |
| futex_down(&fibril_futex); |
| if (list_empty(&manager_list)) { |
| futex_up(&psthread_futex); |
| futex_up(&fibril_futex); |
| return; |
| } |
| list_remove(manager_list.next); |
| futex_up(&psthread_futex); |
| futex_up(&fibril_futex); |
| } |
| |
| /** Return thread id of the currently running thread. |
| /** Return fibril id of the currently running fibril. |
| * |
| * @return Pseudo thread ID of the currently running pseudo thread. |
| * @return Fibril ID of the currently running pseudo thread. |
| */ |
| pstid_t psthread_get_id(void) |
| fid_t fibril_get_id(void) |
| { |
| return (pstid_t) __tcb_get()->pst_data; |
| return (fid_t) __tcb_get()->fibril_data; |
| } |
| |
| /** Disable preemption |
| * |
| * If the thread wants to send several message in a row and does not want to be |
| * If the fibril wants to send several message in a row and does not want to be |
| * preempted, it should start async_serialize_start() in the beginning of |
| * communication and async_serialize_end() in the end. If it is a true |
| * multithreaded application, it should protect the communication channel by a |
| * futex as well. Interrupt messages can still be preempted. |
| */ |
| void psthread_inc_sercount(void) |
| void fibril_inc_sercount(void) |
| { |
| serialization_count++; |
| } |
| |
| /** Restore the preemption counter to the previous state. */ |
| void psthread_dec_sercount(void) |
| void fibril_dec_sercount(void) |
| { |
| serialization_count--; |
| } |