/*
- * Copyright (C) 2016, 2017 "IoT.bzh"
+ * Copyright (C) 2016, 2017, 2018 "IoT.bzh"
* Author José Bollo <jose.bollo@iot.bzh>
*
* Licensed under the Apache License, Version 2.0 (the "License");
#define _GNU_SOURCE
+#if defined(NO_JOBS_WATCHDOG)
+# define HAS_WATCHDOG 0
+#else
+# define HAS_WATCHDOG 1
+#endif
+
#include <stdlib.h>
+#include <stdint.h>
#include <unistd.h>
#include <signal.h>
+#include <string.h>
#include <time.h>
#include <sys/syscall.h>
#include <pthread.h>
#include <errno.h>
#include <assert.h>
+#include <sys/eventfd.h>
+
+#include <systemd/sd-event.h>
+#include "fdev.h"
+#if HAS_WATCHDOG
+#include <systemd/sd-daemon.h>
+#endif
#include "jobs.h"
#include "sig-monitor.h"
#include "verbose.h"
-/* describes pending job */
+#if defined(REMOVE_SYSTEMD_EVENT)
+#include "fdev-epoll.h"
+#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*);
+
+/** Description of a pending job */
struct job
{
- struct job *next; /* link to the next job enqueued */
- void *group; /* group of the request */
- void (*callback)(int,void*,void*,void*); /* processing callback */
- void *arg1; /* first arg */
- void *arg2; /* second arg */
- void *arg3; /* second arg */
- int timeout; /* timeout in second for processing the request */
- int blocked; /* is an other request blocking this one ? */
+ struct job *next; /**< link to the next job enqueued */
+ const void *group; /**< group of the request */
+ job_cb_t callback; /**< processing callback */
+ 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 ? */
};
-/** control of threads */
+/** Description of handled event loops */
+struct evloop
+{
+ unsigned state; /**< encoded state */
+ int efd; /**< event notification */
+ struct sd_event *sdev; /**< the systemd event loop */
+ pthread_cond_t cond; /**< condition */
+ struct fdev *fdev; /**< handling of events */
+};
+
+#define EVLOOP_STATE_WAIT 1U
+#define EVLOOP_STATE_RUN 2U
+#define EVLOOP_STATE_LOCK 4U
+
+/** Description of threads */
struct thread
{
- struct thread *next; /**< next thread of the list */
- struct thread *upper; /**< upper same thread */
- struct job *job; /**< currently processed job */
- pthread_t tid; /**< the thread id */
- unsigned stop: 1; /**< stop requested */
- unsigned lowered: 1; /**< has a lower same thread */
+ struct thread *next; /**< next thread of the list */
+ struct thread *upper; /**< upper same thread */
+ struct job *job; /**< currently processed job */
+ pthread_t tid; /**< the thread id */
+ volatile unsigned stop: 1; /**< stop requested */
+ volatile unsigned waits: 1; /**< is waiting? */
};
+/**
+ * Description of synchonous 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;
static int allowed = 0; /** allowed count of threads */
static int started = 0; /** started count of threads */
static int running = 0; /** running count of threads */
-static int remains = 0; /** remaining count of jobs that can be created */
+static int remains = 0; /** allowed count of waiting jobs */
/* list of threads */
static struct thread *threads;
-static _Thread_local struct thread *current;
+static _Thread_local struct thread *current_thread;
+static _Thread_local struct evloop *current_evloop;
/* queue of pending jobs */
static struct job *first_job;
-static struct job *first_evloop;
static struct job *free_jobs;
+/* event loop */
+static struct evloop evloop[1];
+
+#if defined(REMOVE_SYSTEMD_EVENT)
+static struct fdev_epoll *fdevepoll;
+static int waitevt;
+#endif
+
/**
* 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 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,
- void (*callback)(int, void*, void *, void*),
- void *arg1,
- void *arg2,
- void *arg3)
+ job_cb_t callback,
+ void *arg)
{
struct job *job;
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;
+ errno = ENOMEM;
goto end;
}
}
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:
return job;
}
/**
- * 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 blackers */
+ /* search end and blockers */
pjob = &first_job;
ijob = first_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;
}
/**
* Get the next job to process or NULL if none.
- * The returned job if any isn't removed from
- * the list of jobs.
- * @return the job to process
+ * @return the first job that isn't blocked or NULL
*/
static inline struct job *job_get()
{
- struct job *job;
-
- job = first_job;
+ struct job *job = first_job;
while (job && job->blocked)
job = job->next;
return job;
}
/**
- * Releases the processed 'job'
+ * Releases the processed 'job': removes it
+ * from the list of jobs and unblock the first
+ * pending job of the same group if any.
* @param job the job to release
*/
static inline void job_release(struct job *job)
{
struct job *ijob, **pjob;
- void *group;
+ const void *group;
/* first unqueue the job */
pjob = &first_job;
free_jobs = job;
}
-/** monitored call to the job */
-static void job_call(int signum, void *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
+ */
+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 of the job */
-static void job_cancel(int signum, void *arg)
+#if defined(REMOVE_SYSTEMD_EVENT)
+/**
+ * Gets a fdev_epoll item.
+ * @return a fdev_epoll or NULL in case of error
+ */
+static struct fdev_epoll *get_fdevepoll()
+{
+ struct fdev_epoll *result;
+
+ result = fdevepoll;
+ if (!result)
+ result = fdevepoll = fdev_epoll_create();
+
+ return result;
+}
+#endif
+
+/**
+ * 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
+ */
+static void evloop_run(int signum, void *arg)
{
- job_call(SIGABRT, arg);
+ int rc;
+ struct sd_event *se;
+ struct evloop *el = arg;
+
+ if (!signum) {
+ current_evloop = el;
+ __atomic_store_n(&el->state, EVLOOP_STATE_LOCK|EVLOOP_STATE_RUN|EVLOOP_STATE_WAIT, __ATOMIC_RELAXED);
+ se = el->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));
+ }
+ }
+ __atomic_and_fetch(&el->state, ~(EVLOOP_STATE_WAIT), __ATOMIC_RELAXED);
+
+ 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));
+ }
+ }
+ }
+ }
+ __atomic_and_fetch(&el->state, ~(EVLOOP_STATE_WAIT|EVLOOP_STATE_RUN), __ATOMIC_RELAXED);
+}
+
+
+#if defined(REMOVE_SYSTEMD_EVENT)
+/**
+ * Monitored normal loop for waiting events.
+ * @param signum 0 on normal flow or the number
+ * of the signal that interrupted the normal
+ * flow
+ * @param arg the events to run
+ */
+static void monitored_wait_and_dispatch(int signum, void *arg)
+{
+ struct fdev_epoll *fdev_epoll = arg;
+ if (!signum) {
+ fdev_epoll_wait_and_dispatch(fdev_epoll, -1);
+ }
}
+#endif
-/* main loop of processing threads */
-static void thread_run(struct thread *me)
+/**
+ * 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?
+ */
+static void thread_run(volatile struct thread *me)
{
struct thread **prv;
struct job *job;
+#if !defined(REMOVE_SYSTEMD_EVENT)
+ struct evloop *el;
+#endif
- /* init */
+ /* initialize description of itself and link it in the list */
me->tid = pthread_self();
me->stop = 0;
- me->lowered = 0;
- me->upper = current;
- if (current)
- current->lowered = 1;
- else
+ me->waits = 0;
+ me->upper = current_thread;
+ if (!current_thread) {
+ started++;
sig_monitor_init_timeouts();
- current = me;
+ }
me->next = threads;
- threads = me;
+ threads = (struct thread*)me;
+ current_thread = (struct thread*)me;
/* loop until stopped */
- running++;
while (!me->stop) {
+ /* release the event loop */
+ if (current_evloop) {
+ __atomic_and_fetch(¤t_evloop->state, ~EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
+ current_evloop = NULL;
+ }
+
/* get a job */
job = job_get();
- if (!job && first_job && running == 0) {
- /* sad situation!! should not happen */
- ERROR("threads are blocked!");
- job = first_job;
- first_job = job->next;
- }
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 */
- remains++;
- job->blocked = 1;
- me->job = 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);
+#if !defined(REMOVE_SYSTEMD_EVENT)
} else {
- /* no job, check evloop */
- job = first_evloop;
- if (job) {
- /* evloop */
- first_evloop = job->next;
+ /* no job, check events */
+ el = &evloop[0];
+ if (el->sdev && !__atomic_load_n(&el->state, __ATOMIC_RELAXED)) {
+ /* run the events */
+ __atomic_store_n(&el->state, EVLOOP_STATE_LOCK|EVLOOP_STATE_RUN|EVLOOP_STATE_WAIT, __ATOMIC_RELAXED);
+ current_evloop = el;
pthread_mutex_unlock(&mutex);
- sig_monitor(job->timeout, job_call, job);
+ sig_monitor(0, evloop_run, el);
pthread_mutex_lock(&mutex);
- job->next = first_evloop;
- first_evloop = job;
} else {
- /* no job and not evloop */
+ /* no job and not events */
running--;
+ if (!running)
+ ERROR("Entering job deep sleep! Check your bindings.");
+ me->waits = 1;
pthread_cond_wait(&cond, &mutex);
+ me->waits = 0;
running++;
}
+#else
+ } else if (waitevt) {
+ /* no job and not events */
+ running--;
+ if (!running)
+ ERROR("Entering job deep sleep! Check your bindings.");
+ me->waits = 1;
+ pthread_cond_wait(&cond, &mutex);
+ me->waits = 0;
+ running++;
+ } else {
+ /* wait for events */
+ waitevt = 1;
+ pthread_mutex_unlock(&mutex);
+ sig_monitor(0, monitored_wait_and_dispatch, get_fdevepoll());
+ pthread_mutex_lock(&mutex);
+ waitevt = 0;
+#endif
}
}
- running--;
- /* uninit */
+ /* release the event loop */
+ if (current_evloop) {
+ __atomic_and_fetch(¤t_evloop->state, ~EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
+ current_evloop = NULL;
+ }
+
+ /* 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
+ current_thread = me->upper;
+ if (!current_thread) {
sig_monitor_clean_timeouts();
- pthread_mutex_unlock(&mutex);
+ started--;
+ }
}
-/* main loop of processing threads */
-static void *thread_create(void *data)
+/**
+ * Entry point for created threads.
+ * @param data not used
+ * @return NULL
+ */
+static void *thread_main(void *data)
{
struct thread me;
pthread_mutex_lock(&mutex);
+ running++;
thread_run(&me);
+ running--;
pthread_mutex_unlock(&mutex);
return NULL;
}
-/* start a new thread */
+/**
+ * Starts a new thread
+ * @return 0 in case of success or -1 in case of error
+ */
static int start_one_thread()
{
pthread_t tid;
int rc;
- assert(started < allowed);
-
- started++;
- rc = pthread_create(&tid, NULL, thread_create, NULL);
+ rc = pthread_create(&tid, NULL, thread_main, NULL);
if (rc != 0) {
- started--;
- errno = rc;
+ /* errno = rc; */
WARNING("not able to start thread: %m");
rc = -1;
}
return rc;
}
-static int start_one_thread_if_needed()
-{
- int rc;
-
- if (started == running && started < allowed) {
- /* all threads are busy and a new can be started */
- rc = start_one_thread();
- if (rc < 0 && started == 0)
- return rc; /* no thread available */
- }
- return 0;
-}
-
-int jobs_queue0(
- void *group,
- int timeout,
- void (*callback)(int signum))
-{
- return jobs_queue3(group, timeout, (void(*)(int,void*,void*,void*))callback, NULL, NULL, NULL);
-}
-
+/**
+ * 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
+ * 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 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_queue(
- void *group,
+ const void *group,
int timeout,
void (*callback)(int, void*),
void *arg)
-{
- return jobs_queue3(group, timeout, (void(*)(int,void*,void*,void*))callback, arg, NULL, NULL);
-}
-
-int jobs_queue2(
- void *group,
- int timeout,
- void (*callback)(int, void*, void*),
- void *arg1,
- void *arg2)
-{
- return jobs_queue3(group, timeout, (void(*)(int,void*,void*,void*))callback, arg1, arg2, NULL);
-}
-
-/* queue the job to the 'callback' using a separate thread if available */
-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;
pthread_mutex_lock(&mutex);
/* allocates the job */
- job = job_create(group, timeout, callback, arg1, arg2, arg3);
+ job = job_create(group, timeout, callback, arg);
if (!job) {
errno = ENOMEM;
info = "out of memory";
}
/* start a thread if needed */
- rc = start_one_thread_if_needed();
- if (rc < 0) {
- /* failed to start threading */
- info = "can't start first thread";
- goto error2;
+ 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";
+ goto error2;
+ }
}
/* queues the job */
remains--;
- job_add2(job, NULL);
- pthread_mutex_unlock(&mutex);
+ job_add(job);
/* signal an existing job */
pthread_cond_signal(&cond);
+ pthread_mutex_unlock(&mutex);
return 0;
error2:
return -1;
}
-/* initialise the threads */
-int jobs_init(int allowed_count, int start_count, int waiter_count)
+/**
+ * Internal helper function for 'jobs_enter'.
+ * @see jobs_enter, jobs_leave
+ */
+static void enter_cb(int signum, void *closure)
{
- /* records the allowed count */
- allowed = allowed_count;
- started = 0;
- running = 0;
- remains = waiter_count;
+ 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 (*sync_cb)(int signum, void *closure),
+ struct sync *sync
+)
+{
+ struct job *job;
- /* start at least one thread */
pthread_mutex_lock(&mutex);
- while (started < start_count && start_one_thread() == 0);
- pthread_mutex_unlock(&mutex);
- /* end */
- return -(started != start_count);
+ /* allocates the job */
+ job = job_create(group, timeout, sync_cb, sync);
+ if (!job) {
+ ERROR("out of memory");
+ errno = ENOMEM;
+ pthread_mutex_unlock(&mutex);
+ return -1;
+ }
+
+ /* queues the job */
+ job_add(job);
+
+ /* run until stopped */
+ thread_run(&sync->thread);
+ pthread_mutex_unlock(&mutex);
+ return 0;
}
-int jobs_invoke0(
+/**
+ * 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 (*callback)(int signum, void *closure, struct jobloop *jobloop),
+ void *closure
+)
{
- return jobs_invoke3(timeout, (void(*)(int,void*,void*,void*))callback, NULL, NULL, NULL);
+ 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);
+ t = threads;
+ while (t && t != (struct thread*)jobloop)
+ t = t->next;
+ if (!t) {
+ errno = EINVAL;
+ } else {
+ t->stop = 1;
+ if (t->waits)
+ pthread_cond_broadcast(&cond);
+ }
+ pthread_mutex_unlock(&mutex);
+ return -!t;
}
-int jobs_invoke(
+/**
+ * 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)
{
- return jobs_invoke3(timeout, (void(*)(int,void*,void*,void*))callback, arg, NULL, NULL);
+ struct sync sync;
+
+ sync.callback = callback;
+ sync.arg = arg;
+
+ return do_sync(group, timeout, call_cb, &sync);
}
-int jobs_invoke2(
- int timeout,
- void (*callback)(int, void*, void*),
- void *arg1,
- void *arg2)
+/**
+ * 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)
+{
+ uint64_t x;
+ struct evloop *evloop = userdata;
+ read(evloop->efd, &x, sizeof x);
+ pthread_mutex_lock(&mutex);
+ pthread_cond_broadcast(&evloop->cond);
+ pthread_mutex_unlock(&mutex);
+ return 1;
+}
+
+/* temporary hack */
+#if !defined(REMOVE_SYSTEMD_EVENT)
+__attribute__((unused))
+#endif
+static void evloop_callback(void *arg, uint32_t event, struct fdev *fdev)
+{
+ sig_monitor(0, evloop_run, arg);
+}
+
+/**
+ * Gets a sd_event item for the current thread.
+ * @return a sd_event or NULL in case of error
+ */
+static struct sd_event *get_sd_event_locked()
+{
+ struct evloop *el;
+ uint64_t x;
+ int rc;
+
+ /* creates the evloop on need */
+ el = &evloop[0];
+ if (!el->sdev) {
+ /* start the creation */
+ el->state = 0;
+ /* creates the eventfd for waking up polls */
+ el->efd = eventfd(0, EFD_CLOEXEC);
+ if (el->efd < 0) {
+ ERROR("can't make eventfd for events");
+ goto error1;
+ }
+ /* create the systemd event loop */
+ rc = sd_event_new(&el->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(el->sdev, NULL, el->efd, EPOLLIN, on_evloop_efd, el);
+ if (rc < 0) {
+ ERROR("can't register eventfd");
+#if !defined(REMOVE_SYSTEMD_EVENT)
+ sd_event_unref(el->sdev);
+ el->sdev = NULL;
+error2:
+ close(el->efd);
+error1:
+ return NULL;
+ }
+#else
+ goto error3;
+ }
+ /* handle the event loop */
+ el->fdev = fdev_epoll_add(get_fdevepoll(), sd_event_get_fd(el->sdev));
+ if (!el->fdev) {
+ ERROR("can't create fdev");
+error3:
+ sd_event_unref(el->sdev);
+error2:
+ close(el->efd);
+error1:
+ memset(el, 0, sizeof *el);
+ return NULL;
+ }
+ fdev_set_autoclose(el->fdev, 0);
+ fdev_set_events(el->fdev, EPOLLIN);
+ fdev_set_callback(el->fdev, evloop_callback, el);
+#endif
+ }
+
+ /* attach the event loop to the current thread */
+ if (current_evloop != el) {
+ if (current_evloop)
+ __atomic_and_fetch(¤t_evloop->state, ~EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
+ current_evloop = el;
+ __atomic_or_fetch(&el->state, EVLOOP_STATE_LOCK, __ATOMIC_RELAXED);
+ }
+
+ /* wait for a modifiable event loop */
+ while (__atomic_load_n(&el->state, __ATOMIC_RELAXED) & EVLOOP_STATE_WAIT) {
+ x = 1;
+ write(el->efd, &x, sizeof x);
+ pthread_cond_wait(&el->cond, &mutex);
+ }
+
+ return el->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()
{
- return jobs_invoke3(timeout, (void(*)(int,void*,void*,void*))callback, arg1, arg2, NULL);
+ struct sd_event *result;
+
+ pthread_mutex_lock(&mutex);
+ result = get_sd_event_locked();
+ pthread_mutex_unlock(&mutex);
+
+ return result;
}
-static void unlock_invoker(int signum, void *arg1, void *arg2, void *arg3)
+#if defined(REMOVE_SYSTEMD_EVENT)
+/**
+ * Gets the fdev_epoll item.
+ * @return a fdev_epoll or NULL in case of error
+ */
+struct fdev_epoll *jobs_get_fdev_epoll()
{
- struct thread *t = arg1;
+ struct fdev_epoll *result;
+
pthread_mutex_lock(&mutex);
- t->stop = 1;
+ result = get_fdevepoll();
pthread_mutex_unlock(&mutex);
+
+ return result;
}
+#endif
-/* invoke the job to the 'callback' using a separate thread if available */
-int jobs_invoke3(
- int timeout,
- void (*callback)(int, void*, void *, void*),
- void *arg1,
- void *arg2,
- void *arg3)
+/**
+ * Enter the jobs processing loop.
+ * @param allowed_count Maximum count of thread for jobs including this one
+ * @param start_count Count of thread to start now, must be lower.
+ * @param waiter_count Maximum count of jobs that can be waiting.
+ * @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 signum, void* arg), void *arg)
{
- const char *info;
- struct job *job1, *job2;
- int rc;
+ int rc, launched;
struct thread me;
-
+ 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);
- /* 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) {
- errno = ENOMEM;
- info = "out of memory";
+ /* check whether already running */
+ if (current_thread || allowed) {
+ ERROR("thread already started");
+ errno = EINVAL;
goto error;
}
- /* start a thread if needed */
- rc = start_one_thread_if_needed();
- if (rc < 0) {
- /* failed to start threading */
- info = "can't start first thread";
- goto error;
+ /* records the allowed count */
+ allowed = allowed_count;
+ started = 0;
+ running = 0;
+ remains = waiter_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 */
+ launched = 0;
+ while ((launched + 1) < start_count) {
+ if (start_one_thread() != 0) {
+ ERROR("Not all threads can be started");
+ goto error;
+ }
+ launched++;
}
- /* queues the job */
- job_add2(job1, job2);
+ /* queue the start job */
+ job = job_create(NULL, 0, start, arg);
+ if (!job) {
+ ERROR("out of memory");
+ errno = ENOMEM;
+ goto error;
+ }
+ job_add(job);
+ remains--;
- /* run untill stopped */
+ /* run until end */
thread_run(&me);
- pthread_mutex_unlock(&mutex);
- return 0;
-
+ rc = 0;
error:
- if (job1) {
- job1->next = free_jobs;
- free_jobs = job1;
- }
- if (job2) {
- job2->next = free_jobs;
- free_jobs = job2;
- }
- ERROR("can't process job with threads: %s, %m", info);
pthread_mutex_unlock(&mutex);
- return -1;
+ return rc;
}
-/* terminate all the threads and all pending requests */
+/**
+ * Terminate all the threads and cancel all pending jobs.
+ */
void jobs_terminate()
{
struct job *job, *head, *tail;
- pthread_t me, other;
+ 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;
- for(;;) {
- /* search the next thread to stop */
- t = threads;
- while (t && pthread_equal(t->tid, me))
- t = t->next;
- if (!t)
- break;
- /* stop it */
- other = t->tid;
+
+ /* 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;
+ t = t->next;
+ }
+
+ /* stops the threads */
+ t = threads;
+ while (t) {
t->stop = 1;
- pthread_mutex_unlock(&mutex);
- pthread_cond_broadcast(&cond);
- pthread_join(other, NULL);
- pthread_mutex_lock(&mutex);
+ 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;
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) {
pthread_mutex_unlock(&mutex);
}
-int jobs_add_event_loop(void *key, int timeout, void (*evloop)(int signum, void*), void *closure)
-{
- struct job *job;
-
- pthread_mutex_lock(&mutex);
- job = job_create(key, timeout, (void (*)(int, void *, void *, void *))evloop, closure, NULL, NULL);
- if (job) {
- /* adds the loop */
- job->next = first_evloop;
- first_evloop = job;
-
- /* signal the loop */
- pthread_cond_signal(&cond);
- }
- pthread_mutex_unlock(&mutex);
- return -!job;
-}
-
-int jobs_add_me()
-{
- struct thread me;
-
- /* check whether already running */
- if (current) {
- ERROR("thread already running");
- errno = EINVAL;
- return -1;
- }
-
- /* allowed... */
- pthread_mutex_lock(&mutex);
- allowed++;
- thread_run(&me);
- allowed--;
- pthread_mutex_unlock(&mutex);
- return 0;
-}
-
-
Code Review / src / app-framework-binder.git / blobdiff