X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fjobs.c;h=c2a2ec341baed4669decf4be3cbbb77e78d41411;hb=65353dce81a629e042800bb7b86fcd869a76727e;hp=3d912a54c1307f5c8d7d253a3b151a558a730be1;hpb=c9ba2ce49808a19a4ef982280a46256797b830ae;p=src%2Fapp-framework-binder.git diff --git a/src/jobs.c b/src/jobs.c index 3d912a54..c2a2ec34 100644 --- a/src/jobs.c +++ b/src/jobs.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2016, 2017 "IoT.bzh" + * Copyright (C) 2015-2020 "IoT.bzh" * Author José Bollo * * Licensed under the Apache License, Version 2.0 (the "License"); @@ -18,116 +18,133 @@ #define _GNU_SOURCE #include +#include #include #include +#include #include #include #include #include #include +#include #include #include "jobs.h" +#include "evmgr.h" #include "sig-monitor.h" #include "verbose.h" +#include "systemd.h" -#if 0 -#define _alert_ "do you really want to remove monitoring?" -#define sig_monitor_init_timeouts() ((void)0) -#define sig_monitor_clean_timeouts() ((void)0) -#define sig_monitor(to,cb,arg) (cb(0,arg)) -#endif +#define EVENT_TIMEOUT_TOP ((uint64_t)-1) +#define EVENT_TIMEOUT_CHILD ((uint64_t)10000) /** Internal shortcut for callback */ -typedef void (*job_cb_t)(int, void*, void *, void*); +typedef void (*job_cb_t)(int, void*); + +/** starting mode for jobs */ +enum start_mode +{ + Start_Default, /**< Start a thread if more than one jobs is pending */ + Start_Urgent, /**< Always start a thread */ + Start_Lazy /**< Never start a thread */ +}; /** Description of a pending job */ struct job { struct job *next; /**< link to the next job enqueued */ - void *group; /**< group of the request */ + const void *group; /**< group of the request */ job_cb_t callback; /**< processing callback */ - void *arg1; /**< first arg */ - void *arg2; /**< second arg */ - void *arg3; /**< third arg */ + void *arg; /**< argument */ int timeout; /**< timeout in second for processing the request */ unsigned blocked: 1; /**< is an other request blocking this one ? */ unsigned dropped: 1; /**< is removed ? */ }; -/** Description of handled event loops */ -struct events -{ - struct events *next; - struct sd_event *event; - unsigned runs: 1; -}; - /** Description of threads */ struct thread { struct thread *next; /**< next thread of the list */ struct thread *upper; /**< upper same thread */ + struct thread *nholder;/**< next holder for evloop */ + pthread_cond_t *cwhold;/**< condition wait for holding */ struct job *job; /**< currently processed job */ - struct events *events; /**< currently processed job */ pthread_t tid; /**< the thread id */ - unsigned stop: 1; /**< stop requested */ - unsigned lowered: 1; /**< has a lower same thread */ - unsigned waits: 1; /**< is waiting? */ + volatile unsigned stop: 1; /**< stop requested */ + volatile unsigned waits: 1; /**< is waiting? */ + volatile unsigned leaved: 1; /**< was leaved? */ +}; + +/** + * Description of synchronous callback + */ +struct sync +{ + struct thread thread; /**< thread loop data */ + union { + void (*callback)(int, void*); /**< the synchronous callback */ + void (*enter)(int signum, void *closure, struct jobloop *jobloop); + /**< the entering synchronous routine */ + }; + void *arg; /**< the argument of the callback */ }; /* synchronisation of threads */ static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; static pthread_cond_t cond = PTHREAD_COND_INITIALIZER; -/* count allowed, started and waiting threads */ -static int allowed = 0; /** allowed count of threads */ -static int started = 0; /** started count of threads */ -static int waiting = 0; /** waiting count of threads */ -static int remains = 0; /** allowed count of waiting jobs */ -static int nevents = 0; /** count of events */ +/* counts for threads */ +static int allowed_thread_count = 0; /** allowed count of threads */ +static int started_thread_count = 0; /** started count of threads */ +static int busy_thread_count = 0; /** count of busy threads */ /* list of threads */ static struct thread *threads; -static _Thread_local struct thread *current; +static _Thread_local struct thread *current_thread; + +/* counts for jobs */ +static int remaining_job_count = 0; /** count of job that can be created */ +static int allowed_job_count = 0; /** allowed count of pending jobs */ /* queue of pending jobs */ -static struct job *first_job; -static struct events *first_events; -static struct job *free_jobs; +static struct job *first_pending_job; +static struct job *first_free_job; + +/* event loop */ +static struct evmgr *evmgr; + +static void (*exit_handler)(); /** * Create a new job with the given parameters * @param group the group of the job * @param timeout the timeout of the job (0 if none) * @param callback the function that achieves the job - * @param arg1 the first argument of the callback - * @param arg2 the second argument of the callback - * @param arg3 the third argument of the callback + * @param arg the argument of the callback * @return the created job unblock or NULL when no more memory */ static struct job *job_create( - void *group, + const void *group, int timeout, job_cb_t callback, - void *arg1, - void *arg2, - void *arg3) + void *arg) { struct job *job; /* try recyle existing job */ - job = free_jobs; + job = first_free_job; if (job) - free_jobs = job->next; + first_free_job = job->next; else { - /* allocation without blocking */ + /* allocation without blocking */ pthread_mutex_unlock(&mutex); job = malloc(sizeof *job); pthread_mutex_lock(&mutex); if (!job) { - errno = -ENOMEM; + ERROR("out of memory"); + errno = ENOMEM; goto end; } } @@ -135,9 +152,7 @@ static struct job *job_create( job->group = group; job->timeout = timeout; job->callback = callback; - job->arg1 = arg1; - job->arg2 = arg2; - job->arg3 = arg3; + job->arg = arg; job->blocked = 0; job->dropped = 0; end: @@ -145,45 +160,32 @@ end: } /** - * Adds 'job1' and 'job2' at the end of the list of jobs, marking it + * Adds 'job' at the end of the list of jobs, marking it * as blocked if an other job with the same group is pending. - * @param job1 the first job to add - * @param job2 the second job to add or NULL + * @param job the job to add */ -static void job_add2(struct job *job1, struct job *job2) +static void job_add(struct job *job) { - void *group1, *group2, *group; + const void *group; struct job *ijob, **pjob; /* prepare to add */ - group1 = job1->group; - job1->next = job2; - if (!job2) - group2 = NULL; - else { - job2->next = NULL; - group2 = job2->group; - if (group2 && group2 == group1) - job2->blocked = 1; - } + group = job->group; + job->next = NULL; /* search end and blockers */ - pjob = &first_job; - ijob = first_job; + pjob = &first_pending_job; + ijob = first_pending_job; while (ijob) { - group = ijob->group; - if (group) { - if (group == group1) - job1->blocked = 1; - if (group == group2) - job2->blocked = 1; - } + if (group && ijob->group == group) + job->blocked = 1; pjob = &ijob->next; ijob = ijob->next; } /* queue the jobs */ - *pjob = job1; + *pjob = job; + remaining_job_count--; } /** @@ -192,24 +194,14 @@ static void job_add2(struct job *job1, struct job *job2) */ static inline struct job *job_get() { - struct job *job = first_job; + struct job *job = first_pending_job; while (job && job->blocked) job = job->next; + if (job) + remaining_job_count++; return job; } -/** - * Get the next events to process or NULL if none. - * @return the first events that isn't running or NULL - */ -static inline struct events *events_get() -{ - struct events *events = first_events; - while (events && events->runs) - events = events->next; - return events; -} - /** * Releases the processed 'job': removes it * from the list of jobs and unblock the first @@ -219,11 +211,11 @@ static inline struct events *events_get() static inline void job_release(struct job *job) { struct job *ijob, **pjob; - void *group; + const void *group; /* first unqueue the job */ - pjob = &first_job; - ijob = first_job; + pjob = &first_pending_job; + ijob = first_pending_job; while (ijob != job) { pjob = &ijob->next; ijob = ijob->next; @@ -241,145 +233,224 @@ static inline void job_release(struct job *job) } /* recycle the job */ - job->next = free_jobs; - free_jobs = job; + job->next = first_free_job; + first_free_job = job; } /** - * Monitored normal callback for a job. + * Monitored cancel callback for a job. * This function is called by the monitor - * to run the job when the safe environment + * to cancel the job when the safe environment * is set. * @param signum 0 on normal flow or the number * of the signal that interrupted the normal - * flow - * @param arg the job to run + * flow, isn't used + * @param arg the job to run */ -static void job_call(int signum, void *arg) +__attribute__((unused)) +static void job_cancel(int signum, void *arg) { struct job *job = arg; - job->callback(signum, job->arg1, job->arg2, job->arg3); + job->callback(SIGABRT, job->arg); } /** - * Monitored cancel callback for a job. - * This function is called by the monitor - * to cancel the job when the safe environment - * is set. - * @param signum 0 on normal flow or the number - * of the signal that interrupted the normal - * flow, isn't used - * @param arg the job to run + * wakeup the event loop if needed by sending + * an event. */ -static void job_cancel(int signum, void *arg) +static void evloop_wakeup() { - job_call(SIGABRT, arg); + if (evmgr) + evmgr_wakeup(evmgr); } /** - * Monitored normal callback for events. - * This function is called by the monitor - * to run the event loop when the safe environment - * is set. - * @param signum 0 on normal flow or the number - * of the signal that interrupted the normal - * flow - * @param arg the events to run + * Release the currently held event loop */ -static void events_call(int signum, void *arg) +static void evloop_release() { - struct events *events = arg; - if (!signum) - sd_event_run(events->event, (uint64_t) -1); + struct thread *nh, *ct = current_thread; + + if (ct && evmgr && evmgr_release_if(evmgr, ct)) { + nh = ct->nholder; + ct->nholder = 0; + if (nh) { + evmgr_try_hold(evmgr, nh); + pthread_cond_signal(nh->cwhold); + } + } } /** - * Main processing loop of threads processing jobs. - * The loop must be called with the mutex locked - * and it returns with the mutex locked. - * @param me the description of the thread to use - * TODO: how are timeout handled when reentering? + * get the eventloop for the current thread */ -static void thread_run(volatile struct thread *me) +static int evloop_get() { - struct thread **prv; - struct job *job; - struct events *events; + return evmgr && evmgr_try_hold(evmgr, current_thread); +} + +/** + * acquire the eventloop for the current thread + */ +static void evloop_acquire() +{ + struct thread *pwait, *ct; + pthread_cond_t cond; + + /* try to get the evloop */ + if (!evloop_get()) { + /* failed, init waiting state */ + ct = current_thread; + ct->nholder = NULL; + ct->cwhold = &cond; + pthread_cond_init(&cond, NULL); + + /* queue current thread in holder list */ + pwait = evmgr_holder(evmgr); + while (pwait->nholder) + pwait = pwait->nholder; + pwait->nholder = ct; + + /* wake up the evloop */ + evloop_wakeup(); + + /* wait to acquire the evloop */ + pthread_cond_wait(&cond, &mutex); + pthread_cond_destroy(&cond); + } +} +/** + * Enter the thread + * @param me the description of the thread to enter + */ +static void thread_enter(volatile struct thread *me) +{ + evloop_release(); /* initialize description of itself and link it in the list */ me->tid = pthread_self(); me->stop = 0; - me->lowered = 0; me->waits = 0; - me->upper = current; - if (current) - current->lowered = 1; - else - sig_monitor_init_timeouts(); - current = (struct thread*)me; + me->leaved = 0; + me->nholder = 0; + me->upper = current_thread; me->next = threads; threads = (struct thread*)me; - started++; + current_thread = (struct thread*)me; +} + +/** + * leave the thread + * @param me the description of the thread to leave + */ +static void thread_leave() +{ + struct thread **prv, *me; + + /* unlink the current thread and cleanup */ + me = current_thread; + prv = &threads; + while (*prv != me) + prv = &(*prv)->next; + *prv = me->next; + + current_thread = me->upper; +} + +/** + * Main processing loop of internal threads with processing jobs. + * The loop must be called with the mutex locked + * and it returns with the mutex locked. + * @param me the description of the thread to use + * TODO: how are timeout handled when reentering? + */ +static void thread_run_internal(volatile struct thread *me) +{ + struct job *job; + + /* enter thread */ + thread_enter(me); /* loop until stopped */ - me->events = NULL; while (!me->stop) { + /* release the current event loop */ + evloop_release(); + /* get a job */ - job = job_get(first_job); + job = job_get(); if (job) { /* prepare running the job */ - remains++; /* increases count of job that can wait */ job->blocked = 1; /* mark job as blocked */ me->job = job; /* record the job (only for terminate) */ /* run the job */ pthread_mutex_unlock(&mutex); - sig_monitor(job->timeout, job_call, job); + sig_monitor(job->timeout, job->callback, job->arg); pthread_mutex_lock(&mutex); /* release the run job */ job_release(job); - - /* release event if any */ - events = me->events; - if (events) { - events->runs = 0; - me->events = NULL; + /* no job, check event loop wait */ + } else if (evloop_get()) { + if (!evmgr_can_run(evmgr)) { + /* busy ? */ + CRITICAL("Can't enter dispatch while in dispatch!"); + abort(); } + /* run the events */ + evmgr_prepare_run(evmgr); + pthread_mutex_unlock(&mutex); + sig_monitor(0, (void(*)(int,void*))evmgr_job_run, evmgr); + pthread_mutex_lock(&mutex); } else { - /* no job, check events */ - events = events_get(); - if (events) { - /* run the events */ - events->runs = 1; - me->events = events; - pthread_mutex_unlock(&mutex); - sig_monitor(0, events_call, events); - pthread_mutex_lock(&mutex); - events->runs = 0; - me->events = NULL; - } else { - /* no job and not events */ - waiting++; - me->waits = 1; - pthread_cond_wait(&cond, &mutex); - me->waits = 0; - waiting--; - } + /* no job and no event loop */ + busy_thread_count--; + if (!busy_thread_count) + ERROR("Entering job deep sleep! Check your bindings."); + me->waits = 1; + pthread_cond_wait(&cond, &mutex); + me->waits = 0; + busy_thread_count++; } } + /* cleanup */ + evloop_release(); + thread_leave(); +} - /* unlink the current thread and cleanup */ - started--; - prv = &threads; - while (*prv != me) - prv = &(*prv)->next; - *prv = me->next; - current = me->upper; - if (current) - current->lowered = 0; - else - sig_monitor_clean_timeouts(); +/** + * Main processing loop of external threads. + * The loop must be called with the mutex locked + * and it returns with the mutex locked. + * @param me the description of the thread to use + */ +static void thread_run_external(volatile struct thread *me) +{ + /* enter thread */ + thread_enter(me); + + /* loop until stopped */ + me->waits = 1; + while (!me->stop) + pthread_cond_wait(&cond, &mutex); + me->waits = 0; + thread_leave(); +} + +/** + * Root for created threads. + */ +static void thread_main() +{ + struct thread me; + + busy_thread_count++; + started_thread_count++; + sig_monitor_init_timeouts(); + thread_run_internal(&me); + sig_monitor_clean_timeouts(); + started_thread_count--; + busy_thread_count--; } /** @@ -387,12 +458,10 @@ static void thread_run(volatile struct thread *me) * @param data not used * @return NULL */ -static void *thread_main(void *data) +static void *thread_starter(void *data) { - struct thread me; - pthread_mutex_lock(&mutex); - thread_run(&me); + thread_main(); pthread_mutex_unlock(&mutex); return NULL; } @@ -406,7 +475,7 @@ static int start_one_thread() pthread_t tid; int rc; - rc = pthread_create(&tid, NULL, thread_main, NULL); + rc = pthread_create(&tid, NULL, thread_starter, NULL); if (rc != 0) { /* errno = rc; */ WARNING("not able to start thread: %m"); @@ -416,7 +485,7 @@ static int start_one_thread() } /** - * Queues a new asynchronous job represented by 'callback' + * Queues a new asynchronous job represented by 'callback' and 'arg' * for the 'group' and the 'timeout'. * Jobs are queued FIFO and are possibly executed in parallel * concurrently except for job of the same group that are @@ -427,18 +496,68 @@ static int start_one_thread() * @param callback The function to execute for achieving the job. * Its first parameter is either 0 on normal flow * or the signal number that broke the normal flow. + * The remaining parameter is the parameter 'arg1' + * given here. + * @param arg The second argument for 'callback' + * @param start The start mode for threads * @return 0 in case of success or -1 in case of error */ -int jobs_queue0( - void *group, +static int queue_job_internal( + const void *group, int timeout, - void (*callback)(int signum)) + void (*callback)(int, void*), + void *arg, + enum start_mode start_mode) { - return jobs_queue3(group, timeout, (job_cb_t)callback, NULL, NULL, NULL); + struct job *job; + int rc, busy; + + /* check availability */ + if (remaining_job_count <= 0) { + ERROR("can't process job with threads: too many jobs"); + errno = EBUSY; + goto error; + } + + /* allocates the job */ + job = job_create(group, timeout, callback, arg); + if (!job) + goto error; + + /* start a thread if needed */ + busy = busy_thread_count == started_thread_count; + if (start_mode != Start_Lazy + && busy + && (start_mode == Start_Urgent || remaining_job_count + started_thread_count < allowed_job_count) + && started_thread_count < allowed_thread_count) { + /* all threads are busy and a new can be started */ + rc = start_one_thread(); + if (rc < 0 && started_thread_count == 0) { + ERROR("can't start initial thread: %m"); + goto error2; + } + busy = 0; + } + + /* queues the job */ + job_add(job); + + /* wakeup an evloop if needed */ + if (busy) + evloop_wakeup(); + + pthread_cond_signal(&cond); + return 0; + +error2: + job->next = first_free_job; + first_free_job = job; +error: + return -1; } /** - * Queues a new asynchronous job represented by 'callback' and 'arg1' + * Queues a new asynchronous job represented by 'callback' and 'arg' * for the 'group' and the 'timeout'. * Jobs are queued FIFO and are possibly executed in parallel * concurrently except for job of the same group that are @@ -451,20 +570,28 @@ int jobs_queue0( * or the signal number that broke the normal flow. * The remaining parameter is the parameter 'arg1' * given here. - * @param arg1 The second argument for 'callback' + * @param arg The second argument for 'callback' + * @param start The start mode for threads * @return 0 in case of success or -1 in case of error */ -int jobs_queue( - void *group, +static int queue_job( + const void *group, int timeout, void (*callback)(int, void*), - void *arg) + void *arg, + enum start_mode start_mode) { - return jobs_queue3(group, timeout, (job_cb_t)callback, arg, NULL, NULL); + int rc; + + pthread_mutex_lock(&mutex); + rc = queue_job_internal(group, timeout, callback, arg, start_mode); + pthread_mutex_unlock(&mutex); + return rc; + } /** - * Queues a new asynchronous job represented by 'callback' and 'arg[12]' + * Queues a new asynchronous job represented by 'callback' and 'arg' * for the 'group' and the 'timeout'. * Jobs are queued FIFO and are possibly executed in parallel * concurrently except for job of the same group that are @@ -475,24 +602,22 @@ int jobs_queue( * @param callback The function to execute for achieving the job. * Its first parameter is either 0 on normal flow * or the signal number that broke the normal flow. - * The remaining parameters are the parameters 'arg[12]' + * The remaining parameter is the parameter 'arg1' * given here. - * @param arg1 The second argument for 'callback' - * @param arg2 The third argument for 'callback' + * @param arg The second argument for 'callback' * @return 0 in case of success or -1 in case of error */ -int jobs_queue2( - void *group, +int jobs_queue( + const void *group, int timeout, - void (*callback)(int, void*, void*), - void *arg1, - void *arg2) + void (*callback)(int, void*), + void *arg) { - return jobs_queue3(group, timeout, (job_cb_t)callback, arg1, arg2, NULL); + return queue_job(group, timeout, callback, arg, Start_Default); } /** - * Queues a new asynchronous job represented by 'callback' and 'arg[123]' + * Queues lazyly a new asynchronous job represented by 'callback' and 'arg' * for the 'group' and the 'timeout'. * Jobs are queued FIFO and are possibly executed in parallel * concurrently except for job of the same group that are @@ -503,90 +628,27 @@ int jobs_queue2( * @param callback The function to execute for achieving the job. * Its first parameter is either 0 on normal flow * or the signal number that broke the normal flow. - * The remaining parameters are the parameters 'arg[123]' + * The remaining parameter is the parameter 'arg1' * given here. - * @param arg1 The second argument for 'callback' - * @param arg2 The third argument for 'callback' - * @param arg3 The forth argument for 'callback' - * @return 0 in case of success or -1 in case of error - */ -int jobs_queue3( - void *group, - int timeout, - void (*callback)(int, void*, void *, void*), - void *arg1, - void *arg2, - void *arg3) -{ - const char *info; - struct job *job; - int rc; - - pthread_mutex_lock(&mutex); - - /* allocates the job */ - job = job_create(group, timeout, callback, arg1, arg2, arg3); - if (!job) { - errno = ENOMEM; - info = "out of memory"; - goto error; - } - - /* check availability */ - if (remains == 0) { - errno = EBUSY; - info = "too many jobs"; - goto error2; - } - - /* start a thread if needed */ - if (waiting == 0 && started < allowed) { - /* all threads are busy and a new can be started */ - rc = start_one_thread(); - if (rc < 0 && started == 0) { - info = "can't start first thread"; - goto error2; - } - } - - /* queues the job */ - remains--; - job_add2(job, NULL); - - /* signal an existing job */ - pthread_cond_signal(&cond); - pthread_mutex_unlock(&mutex); - return 0; - -error2: - job->next = free_jobs; - free_jobs = job; -error: - ERROR("can't process job with threads: %s, %m", info); - pthread_mutex_unlock(&mutex); - return -1; -} - -/** - * Run a asynchronous job represented by 'callback' - * with the 'timeout' but only returns after job completion. - * @param timeout The maximum execution time in seconds of the job - * or 0 for unlimited time. - * @param callback The function to execute for achieving the job. - * Its first parameter is either 0 on normal flow - * or the signal number that broke the normal flow. + * @param arg The second argument for 'callback' * @return 0 in case of success or -1 in case of error */ -int jobs_invoke0( +int jobs_queue_lazy( + const void *group, int timeout, - void (*callback)(int signum)) + void (*callback)(int, void*), + void *arg) { - return jobs_invoke3(timeout, (job_cb_t)callback, NULL, NULL, NULL); + return queue_job(group, timeout, callback, arg, Start_Lazy); } /** - * Run a asynchronous job represented by 'callback' and 'arg1' - * with the 'timeout' but only returns after job completion. + * Queues urgently a new asynchronous job represented by 'callback' and 'arg' + * for the 'group' and the 'timeout'. + * Jobs are queued FIFO and are possibly executed in parallel + * concurrently except for job of the same group that are + * executed sequentially in FIFO order. + * @param group The group of the job or NULL when no group. * @param timeout The maximum execution time in seconds of the job * or 0 for unlimited time. * @param callback The function to execute for achieving the job. @@ -594,325 +656,199 @@ int jobs_invoke0( * or the signal number that broke the normal flow. * The remaining parameter is the parameter 'arg1' * given here. - * @param arg1 The second argument for 'callback' + * @param arg The second argument for 'callback' * @return 0 in case of success or -1 in case of error */ -int jobs_invoke( +int jobs_queue_urgent( + const void *group, int timeout, void (*callback)(int, void*), void *arg) { - return jobs_invoke3(timeout, (job_cb_t)callback, arg, NULL, NULL); + return queue_job(group, timeout, callback, arg, Start_Urgent); } /** - * Run a asynchronous job represented by 'callback' and 'arg[12]' - * with the 'timeout' but only returns after job completion. - * @param timeout The maximum execution time in seconds of the job - * or 0 for unlimited time. - * @param callback The function to execute for achieving the job. - * Its first parameter is either 0 on normal flow - * or the signal number that broke the normal flow. - * The remaining parameters are the parameters 'arg[12]' - * given here. - * @param arg1 The second argument for 'callback' - * @param arg2 The third argument for 'callback' - * @return 0 in case of success or -1 in case of error + * Internal helper function for 'jobs_enter'. + * @see jobs_enter, jobs_leave */ -int jobs_invoke2( - int timeout, - void (*callback)(int, void*, void*), - void *arg1, - void *arg2) +static void enter_cb(int signum, void *closure) { - return jobs_invoke3(timeout, (job_cb_t)callback, arg1, arg2, NULL); + struct sync *sync = closure; + sync->enter(signum, sync->arg, (void*)&sync->thread); } /** - * Stops the thread pointed by 'arg1'. Used with - * invoke familly to return to the caller after completion. - * @param signum Unused - * @param arg1 The thread to stop - * @param arg2 Unused - * @param arg3 Unused + * Internal helper function for 'jobs_call'. + * @see jobs_call */ -static void unlock_invoker(int signum, void *arg1, void *arg2, void *arg3) +static void call_cb(int signum, void *closure) { - struct thread *t = arg1; - pthread_mutex_lock(&mutex); - t->stop = 1; - if (t->waits) - pthread_cond_broadcast(&cond); - pthread_mutex_unlock(&mutex); + struct sync *sync = closure; + sync->callback(signum, sync->arg); + jobs_leave((void*)&sync->thread); } /** - * Run a asynchronous job represented by 'callback' and 'arg[123]' - * with the 'timeout' but only returns after job completion. - * @param timeout The maximum execution time in seconds of the job - * or 0 for unlimited time. - * @param callback The function to execute for achieving the job. - * Its first parameter is either 0 on normal flow - * or the signal number that broke the normal flow. - * The remaining parameters are the parameters 'arg[123]' - * given here. - * @param arg1 The second argument for 'callback' - * @param arg2 The third argument for 'callback' - * @param arg3 The forth argument for 'callback' - * @return 0 in case of success or -1 in case of error + * Internal helper for synchronous jobs. It enters + * a new thread loop for evaluating the given job + * as recorded by the couple 'sync_cb' and 'sync'. + * @see jobs_call, jobs_enter, jobs_leave */ -int jobs_invoke3( +static int do_sync( + const void *group, int timeout, - void (*callback)(int, void*, void *, void*), - void *arg1, - void *arg2, - void *arg3) + void (*sync_cb)(int signum, void *closure), + struct sync *sync +) { - struct job *job1, *job2; - struct thread me; - + int rc; + pthread_mutex_lock(&mutex); - /* allocates the job */ - job1 = job_create(&me, timeout, callback, arg1, arg2, arg3); - job2 = job_create(&me, 0, unlock_invoker, &me, NULL, NULL); - if (!job1 || !job2) { - ERROR("out of memory"); - errno = ENOMEM; - if (job1) { - job1->next = free_jobs; - free_jobs = job1; + rc = queue_job_internal(group, timeout, sync_cb, sync, Start_Default); + if (rc == 0) { + /* run until stopped */ + if (current_thread) + thread_run_internal(&sync->thread); + else + thread_run_external(&sync->thread); + if (!sync->thread.leaved) { + errno = EINTR; + rc = -1; } - if (job2) { - job2->next = free_jobs; - free_jobs = job2; - } - pthread_mutex_unlock(&mutex); - return -1; } - - /* queues the job */ - job_add2(job1, job2); - - /* run until stopped */ - thread_run(&me); pthread_mutex_unlock(&mutex); - return 0; + return rc; } /** - * Initialise the job stuff. - * @param allowed_count Maximum count of thread for jobs (can be 0, - * see 'jobs_add_me' for merging new threads) - * @param start_count Count of thread to start now, must be lower. - * @param waiter_count Maximum count of jobs that can be waiting. - * @return 0 in case of success or -1 in case of error. + * Enter a synchronisation point: activates the job given by 'callback' + * and 'closure' using 'group' and 'timeout' to control sequencing and + * execution time. + * @param group the group for sequencing jobs + * @param timeout the time in seconds allocated to the job + * @param callback the callback that will handle the job. + * it receives 3 parameters: 'signum' that will be 0 + * on normal flow or the catched signal number in case + * of interrupted flow, the context 'closure' as given and + * a 'jobloop' reference that must be used when the job is + * terminated to unlock the current execution flow. + * @param closure the argument to the callback + * @return 0 on success or -1 in case of error */ -int jobs_init(int allowed_count, int start_count, int waiter_count) +int jobs_enter( + const void *group, + int timeout, + void (*callback)(int signum, void *closure, struct jobloop *jobloop), + void *closure +) { - int rc, launched; + struct sync sync; - assert(allowed_count >= 0); - assert(start_count >= 0); - assert(waiter_count > 0); - assert(start_count <= allowed_count); - - /* records the allowed count */ - allowed = allowed_count; - started = 0; - waiting = 0; - remains = waiter_count; - - /* start at least one thread */ - pthread_mutex_lock(&mutex); - launched = 0; - while (launched < start_count && start_one_thread() == 0) - launched++; - rc = -(launched != start_count); - pthread_mutex_unlock(&mutex); - - /* end */ - if (rc) - ERROR("Not all threads can be started"); - return rc; + sync.enter = callback; + sync.arg = closure; + return do_sync(group, timeout, enter_cb, &sync); } /** - * Terminate all the threads and cancel all pending jobs. + * Unlocks the execution flow designed by 'jobloop'. + * @param jobloop indication of the flow to unlock + * @return 0 in case of success of -1 on error */ -void jobs_terminate() +int jobs_leave(struct jobloop *jobloop) { - struct job *job, *head, *tail; - pthread_t me, *others; struct thread *t; - int count; - - /* how am i? */ - me = pthread_self(); - /* request all threads to stop */ pthread_mutex_lock(&mutex); - allowed = 0; - - /* count the number of threads */ - count = 0; - t = threads; - while (t) { - if (!t->upper && !pthread_equal(t->tid, me)) - count++; - t = t->next; - } - - /* fill the array of threads */ - others = alloca(count * sizeof *others); - count = 0; t = threads; - while (t) { - if (!t->upper && !pthread_equal(t->tid, me)) - others[count++] = t->tid; + while (t && t != (struct thread*)jobloop) t = t->next; - } - - /* stops the threads */ - t = threads; - while (t) { + if (!t) { + errno = EINVAL; + } else { + t->leaved = 1; t->stop = 1; - t = t->next; - } - - /* wait the threads */ - pthread_cond_broadcast(&cond); - pthread_mutex_unlock(&mutex); - while (count) - pthread_join(others[--count], NULL); - pthread_mutex_lock(&mutex); - - /* cancel pending jobs of other threads */ - remains = 0; - head = first_job; - first_job = NULL; - tail = NULL; - while (head) { - /* unlink the job */ - job = head; - head = job->next; - - /* search if job is stacked for current */ - t = current; - while (t && t->job != job) - t = t->upper; - if (t) { - /* yes, relink it at end */ - if (tail) - tail->next = job; - else - first_job = job; - tail = job; - job->next = NULL; - } else { - /* no cancel the job */ - pthread_mutex_unlock(&mutex); - sig_monitor(0, job_cancel, job); - free(job); - pthread_mutex_lock(&mutex); - } + if (t->waits) + pthread_cond_broadcast(&cond); + else + evloop_wakeup(); } pthread_mutex_unlock(&mutex); + return -!t; } /** - * Adds the current thread to the pool of threads - * processing the jobs. Returns normally when the threads are - * terminated or immediately with an error if the thread is - * already in the pool. + * Calls synchronously the job represented by 'callback' and 'arg1' + * for the 'group' and the 'timeout' and waits for its completion. + * @param group The group of the job or NULL when no group. + * @param timeout The maximum execution time in seconds of the job + * or 0 for unlimited time. + * @param callback The function to execute for achieving the job. + * Its first parameter is either 0 on normal flow + * or the signal number that broke the normal flow. + * The remaining parameter is the parameter 'arg1' + * given here. + * @param arg The second argument for 'callback' * @return 0 in case of success or -1 in case of error */ -int jobs_add_me() +int jobs_call( + const void *group, + int timeout, + void (*callback)(int, void*), + void *arg) { - struct thread me; + struct sync sync; - /* check whether already running */ - if (current) { - ERROR("thread already running"); - errno = EINVAL; - return -1; - } + sync.callback = callback; + sync.arg = arg; - /* allowed... */ - pthread_mutex_lock(&mutex); - allowed++; - thread_run(&me); - allowed--; - pthread_mutex_unlock(&mutex); - return 0; + return do_sync(group, timeout, call_cb, &sync); } /** - * Gets a sd_event item for the current thread. - * @return a sd_event or NULL in case of error + * Ensure that the current running thread can control the event loop. */ -struct sd_event *jobs_get_sd_event() +void jobs_acquire_event_manager() { - struct events *events; - struct thread *me; - int rc; + struct thread lt; + + /* ensure an existing thread environment */ + if (!current_thread) { + memset(<, 0, sizeof lt); + current_thread = < + } + /* lock */ pthread_mutex_lock(&mutex); - /* search events on stack */ - me = current; - while (me && !me->events) - me = me->upper; - if (me) - /* return the stacked events */ - events = me->events; - else { - /* search an available events */ - events = events_get(); - if (!events) { - /* not found, check if creation possible */ - if (nevents >= allowed) { - ERROR("not possible to add a new event"); - events = NULL; - } else { - events = malloc(sizeof *events); - if (events && (rc = sd_event_new(&events->event)) >= 0) { - if (nevents < started || start_one_thread() >= 0) { - events->runs = 0; - events->next = first_events; - first_events = events; - } else { - ERROR("can't start thread for events"); - sd_event_unref(events->event); - free(events); - events = NULL; - } - } else { - if (!events) { - ERROR("out of memory"); - errno = ENOMEM; - } else { - free(events); - ERROR("creation of sd_event failed: %m"); - events = NULL; - errno = -rc; - } - } - } - } - if (events) { - /* */ - me = current; - if (me) { - events->runs = 1; - me->events = events; - } else { - WARNING("event returned for unknown thread!"); - } - } - } + /* creates the evloop on need */ + if (!evmgr) + evmgr_create(&evmgr); + + /* acquire the event loop under lock */ + if (evmgr) + evloop_acquire(); + + /* unlock */ pthread_mutex_unlock(&mutex); - return events ? events->event : NULL; + + /* release the faked thread environment if needed */ + if (current_thread == <) { + /* + * Releasing it is needed because there is no way to guess + * when it has to be released really. But here is where it is + * hazardous: if the caller modifies the eventloop when it + * is waiting, there is no way to make the change effective. + * A workaround to achieve that goal is for the caller to + * require the event loop a second time after having modified it. + */ + NOTICE("Requiring event manager/loop from outside of binder's callback is hazardous!"); + if (verbose_wants(Log_Level_Info)) + sig_monitor_dumpstack(); + evloop_release(); + current_thread = NULL; + } } /** @@ -923,27 +859,88 @@ struct sd_event *jobs_get_sd_event() * @param start The start routine to activate (can't be NULL) * @return 0 in case of success or -1 in case of error. */ -int jobs_enter(int allowed_count, int start_count, int waiter_count, void (*start)()) +int jobs_start( + int allowed_count, + int start_count, + int waiter_count, + void (*start)(int signum, void* arg), + void *arg) { - /* start */ - if (sig_monitor_init() < 0) { - ERROR("failed to initialise signal handlers"); - return -1; + int rc, launched; + struct job *job; + + assert(allowed_count >= 1); + assert(start_count >= 0); + assert(waiter_count > 0); + assert(start_count <= allowed_count); + + rc = -1; + pthread_mutex_lock(&mutex); + + /* check whether already running */ + if (current_thread || allowed_thread_count) { + ERROR("thread already started"); + errno = EINVAL; + goto error; } - /* init job processing */ - if (jobs_init(allowed_count, start_count, waiter_count) < 0) { - ERROR("failed to initialise threading"); - return -1; + /* records the allowed count */ + allowed_thread_count = allowed_count; + started_thread_count = 0; + busy_thread_count = 0; + remaining_job_count = waiter_count; + allowed_job_count = waiter_count; + + /* start at least one thread: the current one */ + launched = 1; + while (launched < start_count) { + if (start_one_thread() != 0) { + ERROR("Not all threads can be started"); + goto error; + } + launched++; } /* queue the start job */ - if (jobs_queue0(NULL, 0, (void(*)(int))start) < 0) { - ERROR("failed to start runnning jobs"); - return -1; - } + job = job_create(NULL, 0, start, arg); + if (!job) + goto error; + job_add(job); - /* turn as processing thread */ - return jobs_add_me(); + /* run until end */ + thread_main(); + rc = 0; +error: + pthread_mutex_unlock(&mutex); + if (exit_handler) + exit_handler(); + return rc; } +/** + * Exit jobs threads and call handler if not NULL. + */ +void jobs_exit(void (*handler)()) +{ + struct thread *t; + + /* request all threads to stop */ + pthread_mutex_lock(&mutex); + + /* set the handler */ + exit_handler = handler; + + /* stops the threads */ + t = threads; + while (t) { + t->stop = 1; + t = t->next; + } + + /* wake up the threads */ + evloop_wakeup(); + pthread_cond_broadcast(&cond); + + /* leave */ + pthread_mutex_unlock(&mutex); +}