diff options
Diffstat (limited to 'src/core/job.c')
| -rw-r--r-- | src/core/job.c | 701 |
1 files changed, 701 insertions, 0 deletions
diff --git a/src/core/job.c b/src/core/job.c new file mode 100644 index 000000000..bae6ab9f3 --- /dev/null +++ b/src/core/job.c @@ -0,0 +1,701 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <assert.h> +#include <errno.h> +#include <sys/timerfd.h> +#include <sys/epoll.h> + +#include "set.h" +#include "unit.h" +#include "macro.h" +#include "strv.h" +#include "load-fragment.h" +#include "load-dropin.h" +#include "log.h" +#include "dbus-job.h" + +Job* job_new(Manager *m, JobType type, Unit *unit) { + Job *j; + + assert(m); + assert(type < _JOB_TYPE_MAX); + assert(unit); + + if (!(j = new0(Job, 1))) + return NULL; + + j->manager = m; + j->id = m->current_job_id++; + j->type = type; + j->unit = unit; + + j->timer_watch.type = WATCH_INVALID; + + /* We don't link it here, that's what job_dependency() is for */ + + return j; +} + +void job_free(Job *j) { + assert(j); + + /* Detach from next 'bigger' objects */ + if (j->installed) { + bus_job_send_removed_signal(j); + + if (j->unit->job == j) { + j->unit->job = NULL; + unit_add_to_gc_queue(j->unit); + } + + hashmap_remove(j->manager->jobs, UINT32_TO_PTR(j->id)); + j->installed = false; + } + + /* Detach from next 'smaller' objects */ + manager_transaction_unlink_job(j->manager, j, true); + + if (j->in_run_queue) + LIST_REMOVE(Job, run_queue, j->manager->run_queue, j); + + if (j->in_dbus_queue) + LIST_REMOVE(Job, dbus_queue, j->manager->dbus_job_queue, j); + + if (j->timer_watch.type != WATCH_INVALID) { + assert(j->timer_watch.type == WATCH_JOB_TIMER); + assert(j->timer_watch.data.job == j); + assert(j->timer_watch.fd >= 0); + + assert_se(epoll_ctl(j->manager->epoll_fd, EPOLL_CTL_DEL, j->timer_watch.fd, NULL) >= 0); + close_nointr_nofail(j->timer_watch.fd); + } + + free(j->bus_client); + free(j); +} + +JobDependency* job_dependency_new(Job *subject, Job *object, bool matters, bool conflicts) { + JobDependency *l; + + assert(object); + + /* Adds a new job link, which encodes that the 'subject' job + * needs the 'object' job in some way. If 'subject' is NULL + * this means the 'anchor' job (i.e. the one the user + * explicitly asked for) is the requester. */ + + if (!(l = new0(JobDependency, 1))) + return NULL; + + l->subject = subject; + l->object = object; + l->matters = matters; + l->conflicts = conflicts; + + if (subject) + LIST_PREPEND(JobDependency, subject, subject->subject_list, l); + else + LIST_PREPEND(JobDependency, subject, object->manager->transaction_anchor, l); + + LIST_PREPEND(JobDependency, object, object->object_list, l); + + return l; +} + +void job_dependency_free(JobDependency *l) { + assert(l); + + if (l->subject) + LIST_REMOVE(JobDependency, subject, l->subject->subject_list, l); + else + LIST_REMOVE(JobDependency, subject, l->object->manager->transaction_anchor, l); + + LIST_REMOVE(JobDependency, object, l->object->object_list, l); + + free(l); +} + +void job_dump(Job *j, FILE*f, const char *prefix) { + assert(j); + assert(f); + + if (!prefix) + prefix = ""; + + fprintf(f, + "%s-> Job %u:\n" + "%s\tAction: %s -> %s\n" + "%s\tState: %s\n" + "%s\tForced: %s\n", + prefix, j->id, + prefix, j->unit->id, job_type_to_string(j->type), + prefix, job_state_to_string(j->state), + prefix, yes_no(j->override)); +} + +bool job_is_anchor(Job *j) { + JobDependency *l; + + assert(j); + + LIST_FOREACH(object, l, j->object_list) + if (!l->subject) + return true; + + return false; +} + +/* + * Merging is commutative, so imagine the matrix as symmetric. We store only + * its lower triangle to avoid duplication. We don't store the main diagonal, + * because A merged with A is simply A. + * + * Merging is associative! A merged with B merged with C is the same as + * A merged with C merged with B. + * + * Mergeability is transitive! If A can be merged with B and B with C then + * A also with C. + * + * Also, if A merged with B cannot be merged with C, then either A or B cannot + * be merged with C either. + */ +static const JobType job_merging_table[] = { +/* What \ With * JOB_START JOB_VERIFY_ACTIVE JOB_STOP JOB_RELOAD JOB_RELOAD_OR_START JOB_RESTART JOB_TRY_RESTART */ +/************************************************************************************************************************************/ +/*JOB_START */ +/*JOB_VERIFY_ACTIVE */ JOB_START, +/*JOB_STOP */ -1, -1, +/*JOB_RELOAD */ JOB_RELOAD_OR_START, JOB_RELOAD, -1, +/*JOB_RELOAD_OR_START*/ JOB_RELOAD_OR_START, JOB_RELOAD_OR_START, -1, JOB_RELOAD_OR_START, +/*JOB_RESTART */ JOB_RESTART, JOB_RESTART, -1, JOB_RESTART, JOB_RESTART, +/*JOB_TRY_RESTART */ JOB_RESTART, JOB_TRY_RESTART, -1, JOB_TRY_RESTART, JOB_RESTART, JOB_RESTART, +}; + +JobType job_type_lookup_merge(JobType a, JobType b) { + assert_cc(ELEMENTSOF(job_merging_table) == _JOB_TYPE_MAX * (_JOB_TYPE_MAX - 1) / 2); + assert(a >= 0 && a < _JOB_TYPE_MAX); + assert(b >= 0 && b < _JOB_TYPE_MAX); + + if (a == b) + return a; + + if (a < b) { + JobType tmp = a; + a = b; + b = tmp; + } + + return job_merging_table[(a - 1) * a / 2 + b]; +} + +bool job_type_is_redundant(JobType a, UnitActiveState b) { + switch (a) { + + case JOB_START: + return + b == UNIT_ACTIVE || + b == UNIT_RELOADING; + + case JOB_STOP: + return + b == UNIT_INACTIVE || + b == UNIT_FAILED; + + case JOB_VERIFY_ACTIVE: + return + b == UNIT_ACTIVE || + b == UNIT_RELOADING; + + case JOB_RELOAD: + return + b == UNIT_RELOADING; + + case JOB_RELOAD_OR_START: + return + b == UNIT_ACTIVATING || + b == UNIT_RELOADING; + + case JOB_RESTART: + return + b == UNIT_ACTIVATING; + + case JOB_TRY_RESTART: + return + b == UNIT_ACTIVATING; + + default: + assert_not_reached("Invalid job type"); + } +} + +bool job_is_runnable(Job *j) { + Iterator i; + Unit *other; + + assert(j); + assert(j->installed); + + /* Checks whether there is any job running for the units this + * job needs to be running after (in the case of a 'positive' + * job type) or before (in the case of a 'negative' job + * type. */ + + /* First check if there is an override */ + if (j->ignore_order) + return true; + + if (j->type == JOB_START || + j->type == JOB_VERIFY_ACTIVE || + j->type == JOB_RELOAD || + j->type == JOB_RELOAD_OR_START) { + + /* Immediate result is that the job is or might be + * started. In this case lets wait for the + * dependencies, regardless whether they are + * starting or stopping something. */ + + SET_FOREACH(other, j->unit->dependencies[UNIT_AFTER], i) + if (other->job) + return false; + } + + /* Also, if something else is being stopped and we should + * change state after it, then lets wait. */ + + SET_FOREACH(other, j->unit->dependencies[UNIT_BEFORE], i) + if (other->job && + (other->job->type == JOB_STOP || + other->job->type == JOB_RESTART || + other->job->type == JOB_TRY_RESTART)) + return false; + + /* This means that for a service a and a service b where b + * shall be started after a: + * + * start a + start b → 1st step start a, 2nd step start b + * start a + stop b → 1st step stop b, 2nd step start a + * stop a + start b → 1st step stop a, 2nd step start b + * stop a + stop b → 1st step stop b, 2nd step stop a + * + * This has the side effect that restarts are properly + * synchronized too. */ + + return true; +} + +static void job_change_type(Job *j, JobType newtype) { + log_debug("Converting job %s/%s -> %s/%s", + j->unit->id, job_type_to_string(j->type), + j->unit->id, job_type_to_string(newtype)); + + j->type = newtype; +} + +int job_run_and_invalidate(Job *j) { + int r; + uint32_t id; + Manager *m; + + assert(j); + assert(j->installed); + + if (j->in_run_queue) { + LIST_REMOVE(Job, run_queue, j->manager->run_queue, j); + j->in_run_queue = false; + } + + if (j->state != JOB_WAITING) + return 0; + + if (!job_is_runnable(j)) + return -EAGAIN; + + j->state = JOB_RUNNING; + job_add_to_dbus_queue(j); + + /* While we execute this operation the job might go away (for + * example: because it is replaced by a new, conflicting + * job.) To make sure we don't access a freed job later on we + * store the id here, so that we can verify the job is still + * valid. */ + id = j->id; + m = j->manager; + + switch (j->type) { + + case JOB_RELOAD_OR_START: + if (unit_active_state(j->unit) == UNIT_ACTIVE) { + job_change_type(j, JOB_RELOAD); + r = unit_reload(j->unit); + break; + } + job_change_type(j, JOB_START); + /* fall through */ + + case JOB_START: + r = unit_start(j->unit); + + /* If this unit cannot be started, then simply wait */ + if (r == -EBADR) + r = 0; + break; + + case JOB_VERIFY_ACTIVE: { + UnitActiveState t = unit_active_state(j->unit); + if (UNIT_IS_ACTIVE_OR_RELOADING(t)) + r = -EALREADY; + else if (t == UNIT_ACTIVATING) + r = -EAGAIN; + else + r = -ENOEXEC; + break; + } + + case JOB_TRY_RESTART: + if (UNIT_IS_INACTIVE_OR_DEACTIVATING(unit_active_state(j->unit))) { + r = -ENOEXEC; + break; + } + job_change_type(j, JOB_RESTART); + /* fall through */ + + case JOB_STOP: + case JOB_RESTART: + r = unit_stop(j->unit); + + /* If this unit cannot stopped, then simply wait. */ + if (r == -EBADR) + r = 0; + break; + + case JOB_RELOAD: + r = unit_reload(j->unit); + break; + + default: + assert_not_reached("Unknown job type"); + } + + if ((j = manager_get_job(m, id))) { + if (r == -EALREADY) + r = job_finish_and_invalidate(j, JOB_DONE); + else if (r == -ENOEXEC) + r = job_finish_and_invalidate(j, JOB_SKIPPED); + else if (r == -EAGAIN) + j->state = JOB_WAITING; + else if (r < 0) + r = job_finish_and_invalidate(j, JOB_FAILED); + } + + return r; +} + +static void job_print_status_message(Unit *u, JobType t, JobResult result) { + assert(u); + + if (t == JOB_START) { + + switch (result) { + + case JOB_DONE: + unit_status_printf(u, ANSI_HIGHLIGHT_GREEN_ON " OK " ANSI_HIGHLIGHT_OFF, "Started %s", unit_description(u)); + break; + + case JOB_FAILED: + unit_status_printf(u, ANSI_HIGHLIGHT_RED_ON "FAILED" ANSI_HIGHLIGHT_OFF, "Failed to start %s", unit_description(u)); + unit_status_printf(u, NULL, "See 'systemctl status %s' for details.", u->id); + break; + + case JOB_DEPENDENCY: + unit_status_printf(u, ANSI_HIGHLIGHT_RED_ON " ABORT" ANSI_HIGHLIGHT_OFF, "Dependency failed. Aborted start of %s", unit_description(u)); + break; + + case JOB_TIMEOUT: + unit_status_printf(u, ANSI_HIGHLIGHT_RED_ON " TIME " ANSI_HIGHLIGHT_OFF, "Timed out starting %s", unit_description(u)); + break; + + default: + ; + } + + } else if (t == JOB_STOP) { + + switch (result) { + + case JOB_TIMEOUT: + unit_status_printf(u, ANSI_HIGHLIGHT_RED_ON " TIME " ANSI_HIGHLIGHT_OFF, "Timed out stopping %s", unit_description(u)); + break; + + case JOB_DONE: + case JOB_FAILED: + unit_status_printf(u, ANSI_HIGHLIGHT_GREEN_ON " OK " ANSI_HIGHLIGHT_OFF, "Stopped %s", unit_description(u)); + break; + + default: + ; + } + } +} + +int job_finish_and_invalidate(Job *j, JobResult result) { + Unit *u; + Unit *other; + JobType t; + Iterator i; + bool recursed = false; + + assert(j); + assert(j->installed); + + job_add_to_dbus_queue(j); + + /* Patch restart jobs so that they become normal start jobs */ + if (result == JOB_DONE && j->type == JOB_RESTART) { + + job_change_type(j, JOB_START); + j->state = JOB_WAITING; + + job_add_to_run_queue(j); + + u = j->unit; + goto finish; + } + + j->result = result; + + log_debug("Job %s/%s finished, result=%s", j->unit->id, job_type_to_string(j->type), job_result_to_string(result)); + + if (result == JOB_FAILED) + j->manager->n_failed_jobs ++; + + u = j->unit; + t = j->type; + job_free(j); + + job_print_status_message(u, t, result); + + /* Fail depending jobs on failure */ + if (result != JOB_DONE) { + + if (t == JOB_START || + t == JOB_VERIFY_ACTIVE || + t == JOB_RELOAD_OR_START) { + + SET_FOREACH(other, u->dependencies[UNIT_REQUIRED_BY], i) + if (other->job && + (other->job->type == JOB_START || + other->job->type == JOB_VERIFY_ACTIVE || + other->job->type == JOB_RELOAD_OR_START)) { + job_finish_and_invalidate(other->job, JOB_DEPENDENCY); + recursed = true; + } + + SET_FOREACH(other, u->dependencies[UNIT_BOUND_BY], i) + if (other->job && + (other->job->type == JOB_START || + other->job->type == JOB_VERIFY_ACTIVE || + other->job->type == JOB_RELOAD_OR_START)) { + job_finish_and_invalidate(other->job, JOB_DEPENDENCY); + recursed = true; + } + + SET_FOREACH(other, u->dependencies[UNIT_REQUIRED_BY_OVERRIDABLE], i) + if (other->job && + !other->job->override && + (other->job->type == JOB_START || + other->job->type == JOB_VERIFY_ACTIVE || + other->job->type == JOB_RELOAD_OR_START)) { + job_finish_and_invalidate(other->job, JOB_DEPENDENCY); + recursed = true; + } + + } else if (t == JOB_STOP) { + + SET_FOREACH(other, u->dependencies[UNIT_CONFLICTED_BY], i) + if (other->job && + (other->job->type == JOB_START || + other->job->type == JOB_VERIFY_ACTIVE || + other->job->type == JOB_RELOAD_OR_START)) { + job_finish_and_invalidate(other->job, JOB_DEPENDENCY); + recursed = true; + } + } + } + + /* Trigger OnFailure dependencies that are not generated by + * the unit itself. We don't tread JOB_CANCELED as failure in + * this context. And JOB_FAILURE is already handled by the + * unit itself. */ + if (result == JOB_TIMEOUT || result == JOB_DEPENDENCY) { + log_notice("Job %s/%s failed with result '%s'.", + u->id, + job_type_to_string(t), + job_result_to_string(result)); + + unit_trigger_on_failure(u); + } + +finish: + /* Try to start the next jobs that can be started */ + SET_FOREACH(other, u->dependencies[UNIT_AFTER], i) + if (other->job) + job_add_to_run_queue(other->job); + SET_FOREACH(other, u->dependencies[UNIT_BEFORE], i) + if (other->job) + job_add_to_run_queue(other->job); + + manager_check_finished(u->manager); + + return recursed; +} + +int job_start_timer(Job *j) { + struct itimerspec its; + struct epoll_event ev; + int fd, r; + assert(j); + + if (j->unit->job_timeout <= 0 || + j->timer_watch.type == WATCH_JOB_TIMER) + return 0; + + assert(j->timer_watch.type == WATCH_INVALID); + + if ((fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC)) < 0) { + r = -errno; + goto fail; + } + + zero(its); + timespec_store(&its.it_value, j->unit->job_timeout); + + if (timerfd_settime(fd, 0, &its, NULL) < 0) { + r = -errno; + goto fail; + } + + zero(ev); + ev.data.ptr = &j->timer_watch; + ev.events = EPOLLIN; + + if (epoll_ctl(j->manager->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) { + r = -errno; + goto fail; + } + + j->timer_watch.type = WATCH_JOB_TIMER; + j->timer_watch.fd = fd; + j->timer_watch.data.job = j; + + return 0; + +fail: + if (fd >= 0) + close_nointr_nofail(fd); + + return r; +} + +void job_add_to_run_queue(Job *j) { + assert(j); + assert(j->installed); + + if (j->in_run_queue) + return; + + LIST_PREPEND(Job, run_queue, j->manager->run_queue, j); + j->in_run_queue = true; +} + +void job_add_to_dbus_queue(Job *j) { + assert(j); + assert(j->installed); + + if (j->in_dbus_queue) + return; + + /* We don't check if anybody is subscribed here, since this + * job might just have been created and not yet assigned to a + * connection/client. */ + + LIST_PREPEND(Job, dbus_queue, j->manager->dbus_job_queue, j); + j->in_dbus_queue = true; +} + +char *job_dbus_path(Job *j) { + char *p; + + assert(j); + + if (asprintf(&p, "/org/freedesktop/systemd1/job/%lu", (unsigned long) j->id) < 0) + return NULL; + + return p; +} + +void job_timer_event(Job *j, uint64_t n_elapsed, Watch *w) { + assert(j); + assert(w == &j->timer_watch); + + log_warning("Job %s/%s timed out.", j->unit->id, job_type_to_string(j->type)); + job_finish_and_invalidate(j, JOB_TIMEOUT); +} + +static const char* const job_state_table[_JOB_STATE_MAX] = { + [JOB_WAITING] = "waiting", + [JOB_RUNNING] = "running" +}; + +DEFINE_STRING_TABLE_LOOKUP(job_state, JobState); + +static const char* const job_type_table[_JOB_TYPE_MAX] = { + [JOB_START] = "start", + [JOB_VERIFY_ACTIVE] = "verify-active", + [JOB_STOP] = "stop", + [JOB_RELOAD] = "reload", + [JOB_RELOAD_OR_START] = "reload-or-start", + [JOB_RESTART] = "restart", + [JOB_TRY_RESTART] = "try-restart", +}; + +DEFINE_STRING_TABLE_LOOKUP(job_type, JobType); + +static const char* const job_mode_table[_JOB_MODE_MAX] = { + [JOB_FAIL] = "fail", + [JOB_REPLACE] = "replace", + [JOB_ISOLATE] = "isolate", + [JOB_IGNORE_DEPENDENCIES] = "ignore-dependencies", + [JOB_IGNORE_REQUIREMENTS] = "ignore-requirements" +}; + +DEFINE_STRING_TABLE_LOOKUP(job_mode, JobMode); + +static const char* const job_result_table[_JOB_RESULT_MAX] = { + [JOB_DONE] = "done", + [JOB_CANCELED] = "canceled", + [JOB_TIMEOUT] = "timeout", + [JOB_FAILED] = "failed", + [JOB_DEPENDENCY] = "dependency", + [JOB_SKIPPED] = "skipped" +}; + +DEFINE_STRING_TABLE_LOOKUP(job_result, JobResult); |