X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fjobs.c;h=e75a11707c7174a5d4bb8445160bb6c86243b0ac;hb=refs%2Fheads%2Fsandbox%2FDDTLK%2Fpakage;hp=1ed20fcb3a57722cfa1fcab81d1704f4bfbf5dc5;hpb=9fe2dfd3c4df334607083f989346090e1051a565;p=src%2Fapp-framework-binder.git diff --git a/src/jobs.c b/src/jobs.c index 1ed20fcb..e75a1170 100644 --- a/src/jobs.c +++ b/src/jobs.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2016, 2017 "IoT.bzh" + * Copyright (C) 2016, 2017, 2018 "IoT.bzh" * Author José Bollo * * Licensed under the Apache License, Version 2.0 (the "License"); @@ -17,108 +17,129 @@ #define _GNU_SOURCE +#if defined(NO_JOBS_WATCHDOG) +# define HAS_WATCHDOG 0 +#else +# define HAS_WATCHDOG 1 +#endif + #include #include #include #include +#include #include #include #include #include #include +#include #include +#include "fdev.h" +#if HAS_WATCHDOG +#include +#endif #include "jobs.h" #include "sig-monitor.h" #include "verbose.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) +struct thread; + /** Internal shortcut for callback */ -typedef void (*job_cb_t)(int, void*, void *, void*); +typedef void (*job_cb_t)(int, void*); /** 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 evloop { - struct events *next; - struct sd_event *event; - uint64_t timeout; - unsigned runs: 1; + unsigned state; /**< encoded state */ + int efd; /**< event notification */ + struct sd_event *sdev; /**< the systemd event loop */ + struct fdev *fdev; /**< handling of events */ + struct thread *holder; /**< holder of the evloop */ }; +#define EVLOOP_STATE_WAIT 1U +#define EVLOOP_STATE_RUN 2U + /** 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? */ +}; + +/** + * 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 */ +/* count allowed, started and running 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 running = 0; /** running count of threads */ static int remains = 0; /** allowed count of waiting jobs */ -static int nevents = 0; /** count of events */ /* list of threads */ static struct thread *threads; -static _Thread_local struct thread *current; +static _Thread_local struct thread *current_thread; /* queue of pending jobs */ static struct job *first_job; -static struct events *first_events; static struct job *free_jobs; +/* event loop */ +static struct evloop evloop; + /** * 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; @@ -127,12 +148,13 @@ static struct job *job_create( if (job) free_jobs = 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; } } @@ -140,9 +162,7 @@ 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: @@ -156,7 +176,7 @@ end: */ static void job_add(struct job *job) { - void *group; + const void *group; struct job *ijob, **pjob; /* prepare to add */ @@ -175,6 +195,7 @@ static void job_add(struct job *job) /* queue the jobs */ *pjob = job; + remains--; } /** @@ -186,21 +207,11 @@ static inline struct job *job_get() struct job *job = first_job; while (job && job->blocked) job = job->next; + if (job) + remains++; 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 @@ -210,7 +221,7 @@ 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; @@ -236,22 +247,6 @@ static inline void job_release(struct job *job) free_jobs = job; } -/** - * Monitored normal callback for a job. - * This function is called by the monitor - * to run 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 - */ -static void job_call(int signum, void *arg) -{ - struct job *job = arg; - job->callback(signum, job->arg1, job->arg2, job->arg3); -} - /** * Monitored cancel callback for a job. * This function is called by the monitor @@ -264,7 +259,8 @@ static void job_call(int signum, void *arg) */ static void job_cancel(int signum, void *arg) { - job_call(SIGABRT, arg); + struct job *job = arg; + job->callback(SIGABRT, job->arg); } /** @@ -277,109 +273,257 @@ static void job_cancel(int signum, void *arg) * flow * @param arg the events to run */ -static void events_call(int signum, void *arg) +static void evloop_run(int signum, void *arg) +{ + int rc; + struct sd_event *se; + + if (!signum) { + se = evloop.sdev; + rc = sd_event_prepare(se); + if (rc < 0) { + errno = -rc; + CRITICAL("sd_event_prepare returned an error (state: %d): %m", sd_event_get_state(se)); + abort(); + } else { + if (rc == 0) { + rc = sd_event_wait(se, (uint64_t)(int64_t)-1); + if (rc < 0) { + errno = -rc; + ERROR("sd_event_wait returned an error (state: %d): %m", sd_event_get_state(se)); + } + } + evloop.state = EVLOOP_STATE_RUN; + if (rc > 0) { + rc = sd_event_dispatch(se); + if (rc < 0) { + errno = -rc; + ERROR("sd_event_dispatch returned an error (state: %d): %m", sd_event_get_state(se)); + } + } + } + } +} + +/** + * Internal callback for evloop management. + * The effect of this function is hidden: it exits + * the waiting poll if any. + */ +static void evloop_on_efd_event() { - struct events *events = arg; - if (!signum) - sd_event_run(events->event, events->timeout); + uint64_t x; + read(evloop.efd, &x, sizeof x); } /** - * 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? + * wakeup the event loop if needed by sending + * an event. */ -static void thread_run(volatile struct thread *me) +static void evloop_wakeup() { - struct thread **prv; - struct job *job; - struct events *events; - uint64_t evto; + uint64_t x; + + if (evloop.state & EVLOOP_STATE_WAIT) { + x = 1; + write(evloop.efd, &x, sizeof x); + } +} + +/** + * Release the currently held event loop + */ +static void evloop_release() +{ + struct thread *nh, *ct = current_thread; + + if (ct && evloop.holder == ct) { + nh = ct->nholder; + evloop.holder = nh; + if (nh) + pthread_cond_signal(nh->cwhold); + } +} + +/** + * get the eventloop for the current thread + */ +static int evloop_get() +{ + struct thread *ct = current_thread; + + if (evloop.holder) + return evloop.holder == ct; + + if (!evloop.sdev) + return 0; + + ct->nholder = NULL; + evloop.holder = ct; + return 1; +} +/** + * 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 = &evloop.holder; + while (*pwait) + pwait = &(*pwait)->nholder; + *pwait = 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; - evto = EVENT_TIMEOUT_CHILD; - } else { - started++; - sig_monitor_init_timeouts(); - evto = EVENT_TIMEOUT_TOP; - } + me->upper = current_thread; me->next = threads; threads = (struct thread*)me; - current = (struct thread*)me; + current_thread = (struct thread*)me; +} - NOTICE("job thread starting %d(/%d) %s", started, allowed, me->upper ? "child" : "parent"); +/** + * 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 (evloop.state != 0) { + /* busy ? */ + CRITICAL("Can't enter dispatch while in dispatch!"); + abort(); } + /* run the events */ + evloop.state = EVLOOP_STATE_RUN|EVLOOP_STATE_WAIT; + pthread_mutex_unlock(&mutex); + sig_monitor(0, evloop_run, NULL); + pthread_mutex_lock(&mutex); + evloop.state = 0; } else { - /* no job, check events */ - events = events_get(); - if (events) { - /* run the events */ - events->runs = 1; - events->timeout = evto; - 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 */ + running--; + if (!running) + ERROR("Entering job deep sleep! Check your bindings."); + me->waits = 1; + pthread_cond_wait(&cond, &mutex); + me->waits = 0; + running++; } } - NOTICE("job thread stoping %d(/%d) %s", started, allowed, me->upper ? "child" : "parent"); + /* cleanup */ + evloop_release(); + thread_leave(); +} - /* unlink the current thread and cleanup */ - prv = &threads; - while (*prv != me) - prv = &(*prv)->next; - *prv = me->next; - current = me->upper; - if (current) { - current->lowered = 0; - } else { - sig_monitor_clean_timeouts(); - started--; - } +/** + * 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; + + running++; + started++; + sig_monitor_init_timeouts(); + thread_run_internal(&me); + sig_monitor_clean_timeouts(); + started--; + running--; } /** @@ -387,12 +531,10 @@ 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 +548,7 @@ 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"); @@ -416,29 +558,7 @@ static int start_one_thread() } /** - * Queues a new asynchronous job represented by 'callback' - * 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. - * Its first parameter is either 0 on normal flow - * or the signal number that broke the normal flow. - * @return 0 in case of success or -1 in case of error - */ -int jobs_queue0( - void *group, - int timeout, - void (*callback)(int signum)) -{ - return jobs_queue3(group, timeout, (job_cb_t)callback, NULL, NULL, NULL); -} - -/** - * 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 @@ -451,106 +571,43 @@ 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' * @return 0 in case of success or -1 in case of error */ int jobs_queue( - void *group, + const void *group, int timeout, void (*callback)(int, void*), void *arg) { - return jobs_queue3(group, timeout, (job_cb_t)callback, arg, NULL, NULL); -} - -/** - * Queues a new asynchronous job represented by 'callback' and 'arg[12]' - * 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. - * 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 - */ -int jobs_queue2( - void *group, - int timeout, - void (*callback)(int, void*, void*), - void *arg1, - void *arg2) -{ - return jobs_queue3(group, timeout, (job_cb_t)callback, arg1, arg2, NULL); -} - -/** - * Queues a new asynchronous job represented by 'callback' and 'arg[123]' - * 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. - * 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 - */ -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"; + job = job_create(group, timeout, callback, arg); + if (!job) goto error; - } /* check availability */ - if (remains == 0) { + if (remains <= 0) { + ERROR("can't process job with threads: too many jobs"); errno = EBUSY; - info = "too many jobs"; goto error2; } /* start a thread if needed */ - if (waiting == 0 && started < allowed) { + if (running == started && 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"; + ERROR("can't start initial thread: %m"); goto error2; } } /* queues the job */ - remains--; job_add(job); /* signal an existing job */ @@ -562,32 +619,51 @@ 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; } /** - * Enter a synchronisation point: activates the job given by 'callback' - * @param group the gro + * Internal helper function for 'jobs_enter'. + * @see jobs_enter, jobs_leave */ -int jobs_enter( - void *group, +static void enter_cb(int signum, void *closure) +{ + struct sync *sync = closure; + sync->enter(signum, sync->arg, (void*)&sync->thread); +} + +/** + * Internal helper function for 'jobs_call'. + * @see jobs_call + */ +static void call_cb(int signum, void *closure) +{ + struct sync *sync = closure; + sync->callback(signum, sync->arg); + jobs_leave((void*)&sync->thread); +} + +/** + * 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 + */ +static int do_sync( + const void *group, int timeout, - void (*callback)(int signum, void *closure, struct jobloop *jobloop), - void *closure) + void (*sync_cb)(int signum, void *closure), + struct sync *sync +) { - struct job *job; - struct thread me; pthread_mutex_lock(&mutex); /* allocates the job */ - job = job_create(group, timeout, (job_cb_t)callback, closure, &me, NULL); + job = job_create(group, timeout, sync_cb, sync); if (!job) { - ERROR("out of memory"); - errno = ENOMEM; pthread_mutex_unlock(&mutex); return -1; } @@ -596,16 +672,53 @@ int jobs_enter( job_add(job); /* run until stopped */ - thread_run(&me); + if (current_thread) + thread_run_internal(&sync->thread); + else + thread_run_external(&sync->thread); pthread_mutex_unlock(&mutex); return 0; } +/** + * 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_enter( + const void *group, + int timeout, + void (*callback)(int signum, void *closure, struct jobloop *jobloop), + void *closure +) +{ + struct sync sync; + + sync.enter = callback; + sync.arg = closure; + return do_sync(group, timeout, enter_cb, &sync); +} + +/** + * 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 + */ int jobs_leave(struct jobloop *jobloop) { struct thread *t; - pthread_mutex_lock(&mutex); + pthread_mutex_lock(&mutex); t = threads; while (t && t != (struct thread*)jobloop) t = t->next; @@ -615,77 +728,134 @@ int jobs_leave(struct jobloop *jobloop) t->stop = 1; if (t->waits) pthread_cond_broadcast(&cond); + else + evloop_wakeup(); } pthread_mutex_unlock(&mutex); return -!t; } +/** + * 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_call( + const void *group, + int timeout, + void (*callback)(int, void*), + void *arg) +{ + struct sync sync; + + sync.callback = callback; + sync.arg = arg; + + return do_sync(group, timeout, call_cb, &sync); +} + +/** + * Internal callback for evloop management. + * The effect of this function is hidden: it exits + * the waiting poll if any. Then it wakes up a thread + * awaiting the evloop using signal. + */ +static int on_evloop_efd(sd_event_source *s, int fd, uint32_t revents, void *userdata) +{ + evloop_on_efd_event(); + return 1; +} + /** * Gets a sd_event item for the current thread. * @return a sd_event or NULL in case of error */ -struct sd_event *jobs_get_sd_event() +static struct sd_event *get_sd_event_locked() { - struct events *events; - struct thread *me; int rc; - 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; - } - } - } + /* creates the evloop on need */ + if (!evloop.sdev) { + /* start the creation */ + evloop.state = 0; + /* creates the eventfd for waking up polls */ + evloop.efd = eventfd(0, EFD_CLOEXEC|EFD_SEMAPHORE); + if (evloop.efd < 0) { + ERROR("can't make eventfd for events"); + goto error1; } - if (events) { - /* */ - me = current; - if (me) { - events->runs = 1; - me->events = events; - } else { - WARNING("event returned for unknown thread!"); - } + /* create the systemd event loop */ + rc = sd_event_new(&evloop.sdev); + if (rc < 0) { + ERROR("can't make new event loop"); + goto error2; + } + /* put the eventfd in the event loop */ + rc = sd_event_add_io(evloop.sdev, NULL, evloop.efd, EPOLLIN, on_evloop_efd, NULL); + if (rc < 0) { + ERROR("can't register eventfd"); + sd_event_unref(evloop.sdev); + evloop.sdev = NULL; +error2: + close(evloop.efd); +error1: + return NULL; } } + + /* acquire the event loop */ + evloop_acquire(); + + return evloop.sdev; +} + +/** + * Gets a sd_event item for the current thread. + * @return a sd_event or NULL in case of error + */ +struct sd_event *jobs_get_sd_event() +{ + struct sd_event *result; + struct thread lt; + + /* ensure an existing thread environment */ + if (!current_thread) { + memset(<, 0, sizeof lt); + current_thread = < + } + + /* process */ + pthread_mutex_lock(&mutex); + result = get_sd_event_locked(); 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 sd_event loop out of binder callbacks is hazardous!"); + if (verbose_wants(Log_Level_Info)) + sig_monitor_dumpstack(); + evloop_release(); + current_thread = NULL; + } + + return result; } /** @@ -696,10 +866,9 @@ 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_start(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) { int rc, launched; - struct thread me; struct job *job; assert(allowed_count >= 1); @@ -711,27 +880,27 @@ int jobs_start(int allowed_count, int start_count, int waiter_count, void (*star pthread_mutex_lock(&mutex); /* check whether already running */ - if (current || allowed) { + if (current_thread || allowed) { ERROR("thread already started"); errno = EINVAL; goto error; } - /* start */ - if (sig_monitor_init() < 0) { - ERROR("failed to initialise signal handlers"); - goto error; - } - /* records the allowed count */ allowed = allowed_count; started = 0; - waiting = 0; + running = 0; remains = waiter_count; - /* start at least one thread */ - launched = 0; - while ((launched + 1) < start_count) { +#if HAS_WATCHDOG + /* set the watchdog */ + if (sd_watchdog_enabled(0, NULL)) + sd_event_set_watchdog(get_sd_event_locked(), 1); +#endif + + /* 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; @@ -740,17 +909,13 @@ int jobs_start(int allowed_count, int start_count, int waiter_count, void (*star } /* queue the start job */ - job = job_create(NULL, 0, (job_cb_t)start, NULL, NULL, NULL); - if (!job) { - ERROR("out of memory"); - errno = ENOMEM; + job = job_create(NULL, 0, start, arg); + if (!job) goto error; - } job_add(job); - remains--; /* run until end */ - thread_run(&me); + thread_main(); rc = 0; error: pthread_mutex_unlock(&mutex); @@ -818,7 +983,7 @@ void jobs_terminate() head = job->next; /* search if job is stacked for current */ - t = current; + t = current_thread; while (t && t->job != job) t = t->upper; if (t) {