Now that we added the job_lock/unlock pairs, we can also rename all static functions in job.c that are called with the job mutex held as _locked(), and add a little comment on top.
No functional change intended. Signed-off-by: Emanuele Giuseppe Esposito <[email protected]> --- blockjob.c | 8 ++ job.c | 243 +++++++++++++++++++++++++++++++---------------------- 2 files changed, 149 insertions(+), 102 deletions(-) diff --git a/blockjob.c b/blockjob.c index e00c8d31d5..cf1f49f6c2 100644 --- a/blockjob.c +++ b/blockjob.c @@ -242,6 +242,7 @@ int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, return 0; } +/* Called with job_mutex lock held. */ static void block_job_on_idle(Notifier *n, void *opaque) { /* @@ -269,6 +270,7 @@ static bool job_timer_pending(Job *job) return timer_pending(&job->sleep_timer); } +/* Called with job_mutex held. May temporarly release the lock. */ bool block_job_set_speed(BlockJob *job, int64_t speed, Error **errp) { const BlockJobDriver *drv = block_job_driver(job); @@ -310,6 +312,7 @@ int64_t block_job_ratelimit_get_delay(BlockJob *job, uint64_t n) return ratelimit_calculate_delay(&job->limit, n); } +/* Called with job_mutex lock held. */ BlockJobInfo *block_job_query(BlockJob *job, Error **errp) { BlockJobInfo *info; @@ -355,6 +358,7 @@ static void block_job_iostatus_set_err(BlockJob *job, int error) } } +/* Called with job_mutex lock held. */ static void block_job_event_cancelled(Notifier *n, void *opaque) { BlockJob *job = opaque; @@ -374,6 +378,7 @@ static void block_job_event_cancelled(Notifier *n, void *opaque) job->speed); } +/* Called with job_mutex lock held. */ static void block_job_event_completed(Notifier *n, void *opaque) { BlockJob *job = opaque; @@ -400,6 +405,7 @@ static void block_job_event_completed(Notifier *n, void *opaque) msg); } +/* Called with job_mutex lock held. */ static void block_job_event_pending(Notifier *n, void *opaque) { BlockJob *job = opaque; @@ -412,6 +418,7 @@ static void block_job_event_pending(Notifier *n, void *opaque) job->job.id); } +/* Called with job_mutex lock held. */ static void block_job_event_ready(Notifier *n, void *opaque) { BlockJob *job = opaque; @@ -504,6 +511,7 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, return job; } +/* Called with job_mutex lock held. */ void block_job_iostatus_reset(BlockJob *job) { assert(qemu_in_main_thread()); diff --git a/job.c b/job.c index 56722a5043..f16a4ef542 100644 --- a/job.c +++ b/job.c @@ -54,6 +54,7 @@ */ QemuMutex job_mutex; +/* Protected by job_mutex */ static QLIST_HEAD(, Job) jobs = QLIST_HEAD_INITIALIZER(jobs); /* Job State Transition Table */ @@ -129,7 +130,8 @@ JobTxn *job_txn_new(void) return txn; } -static void job_txn_ref(JobTxn *txn) +/* Called with job_mutex held. */ +static void job_txn_ref_locked(JobTxn *txn) { txn->refcnt++; } @@ -151,10 +153,11 @@ void job_txn_add_job_locked(JobTxn *txn, Job *job) job->txn = txn; QLIST_INSERT_HEAD(&txn->jobs, job, txn_list); - job_txn_ref(txn); + job_txn_ref_locked(txn); } -static void job_txn_del_job(Job *job) +/* Called with job_mutex held. */ +static void job_txn_del_job_locked(Job *job) { if (job->txn) { QLIST_REMOVE(job, txn_list); @@ -163,17 +166,18 @@ static void job_txn_del_job(Job *job) } } -static int job_txn_apply(Job *job, int fn(Job *)) +/* Called with job_mutex held. */ +static int job_txn_apply_locked(Job *job, int fn(Job *)) { Job *other_job, *next; JobTxn *txn = job->txn; int rc = 0; /* - * Similar to job_completed_txn_abort, we take each job's lock before - * applying fn, but since we assume that outer_ctx is held by the caller, - * we need to release it here to avoid holding the lock twice - which would - * break AIO_WAIT_WHILE from within fn. + * Similar to job_completed_txn_abort_locked, we take each job's lock + * before applying fn, but since we assume that outer_ctx is held by the + * caller, we need to release it here to avoid holding the lock + * twice - which would break AIO_WAIT_WHILE from within fn. */ job_ref_locked(job); aio_context_release(job->aio_context); @@ -199,7 +203,8 @@ bool job_is_internal(Job *job) return (job->id == NULL); } -static void job_state_transition(Job *job, JobStatus s1) +/* Called with job_mutex held. */ +static void job_state_transition_locked(Job *job, JobStatus s1) { JobStatus s0 = job->status; assert(s1 >= 0 && s1 < JOB_STATUS__MAX); @@ -355,7 +360,8 @@ static bool job_started(Job *job) return job->co; } -static bool job_should_pause(Job *job) +/* Called with job_mutex held. */ +static bool job_should_pause_locked(Job *job) { return job->pause_count > 0; } @@ -381,6 +387,7 @@ Job *job_get_locked(const char *id) return NULL; } +/* Called with job_mutex *not* held. */ static void job_sleep_timer_cb(void *opaque) { Job *job = opaque; @@ -434,7 +441,7 @@ void *job_create(const char *job_id, const JobDriver *driver, JobTxn *txn, notifier_list_init(&job->on_pending); notifier_list_init(&job->on_ready); - job_state_transition(job, JOB_STATUS_CREATED); + job_state_transition_locked(job, JOB_STATUS_CREATED); aio_timer_init(qemu_get_aio_context(), &job->sleep_timer, QEMU_CLOCK_REALTIME, SCALE_NS, job_sleep_timer_cb, job); @@ -502,7 +509,7 @@ void job_progress_increase_remaining(Job *job, uint64_t delta) * To be called when a cancelled job is finalised. * Called with job_mutex held. */ -static void job_event_cancelled(Job *job) +static void job_event_cancelled_locked(Job *job) { notifier_list_notify(&job->on_finalize_cancelled, job); } @@ -511,22 +518,25 @@ static void job_event_cancelled(Job *job) * To be called when a successfully completed job is finalised. * Called with job_mutex held. */ -static void job_event_completed(Job *job) +static void job_event_completed_locked(Job *job) { notifier_list_notify(&job->on_finalize_completed, job); } -static void job_event_pending(Job *job) +/* Called with job_mutex held. */ +static void job_event_pending_locked(Job *job) { notifier_list_notify(&job->on_pending, job); } -static void job_event_ready(Job *job) +/* Called with job_mutex held. */ +static void job_event_ready_locked(Job *job) { notifier_list_notify(&job->on_ready, job); } -static void job_event_idle(Job *job) +/* Called with job_mutex held. */ +static void job_event_idle_locked(Job *job) { notifier_list_notify(&job->on_idle, job); } @@ -571,15 +581,18 @@ void job_enter(Job *job) * is allowed and cancels the timer. * * If @ns is (uint64_t) -1, no timer is scheduled and job_enter() must be - * called explicitly. */ -static void coroutine_fn job_do_yield(Job *job, uint64_t ns) + * called explicitly. + * + * Called with job_mutex held, but releases it temporarly. + */ +static void coroutine_fn job_do_yield_locked(Job *job, uint64_t ns) { real_job_lock(); if (ns != -1) { timer_mod(&job->sleep_timer, ns); } job->busy = false; - job_event_idle(job); + job_event_idle_locked(job); real_job_unlock(); job_unlock(); qemu_coroutine_yield(); @@ -594,7 +607,7 @@ void coroutine_fn job_pause_point(Job *job) assert(job && job_started(job)); job_lock(); - if (!job_should_pause(job)) { + if (!job_should_pause_locked(job)) { job_unlock(); return; } @@ -609,15 +622,15 @@ void coroutine_fn job_pause_point(Job *job) job_lock(); } - if (job_should_pause(job) && !job_is_cancelled_locked(job)) { + if (job_should_pause_locked(job) && !job_is_cancelled_locked(job)) { JobStatus status = job->status; - job_state_transition(job, status == JOB_STATUS_READY + job_state_transition_locked(job, status == JOB_STATUS_READY ? JOB_STATUS_STANDBY : JOB_STATUS_PAUSED); job->paused = true; - job_do_yield(job, -1); + job_do_yield_locked(job, -1); job->paused = false; - job_state_transition(job, status); + job_state_transition_locked(job, status); } job_unlock(); @@ -636,8 +649,8 @@ void job_yield(Job *job) return; } - if (!job_should_pause(job)) { - job_do_yield(job, -1); + if (!job_should_pause_locked(job)) { + job_do_yield_locked(job, -1); } } @@ -654,8 +667,9 @@ void coroutine_fn job_sleep_ns(Job *job, int64_t ns) return; } - if (!job_should_pause(job)) { - job_do_yield(job, qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + ns); + if (!job_should_pause_locked(job)) { + job_do_yield_locked(job, + qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + ns); } } @@ -726,16 +740,17 @@ void job_user_resume_locked(Job *job, Error **errp) job_resume_locked(job); } -static void job_do_dismiss(Job *job) +/* Called with job_mutex held. */ +static void job_do_dismiss_locked(Job *job) { assert(job); job->busy = false; job->paused = false; job->deferred_to_main_loop = true; - job_txn_del_job(job); + job_txn_del_job_locked(job); - job_state_transition(job, JOB_STATUS_NULL); + job_state_transition_locked(job, JOB_STATUS_NULL); job_unref_locked(job); } @@ -748,14 +763,14 @@ void job_dismiss_locked(Job **jobptr, Error **errp) return; } - job_do_dismiss(job); + job_do_dismiss_locked(job); *jobptr = NULL; } void job_early_fail_locked(Job *job) { assert(job->status == JOB_STATUS_CREATED); - job_do_dismiss(job); + job_do_dismiss_locked(job); } void job_early_fail(Job *job) @@ -764,15 +779,17 @@ void job_early_fail(Job *job) job_early_fail_locked(job); } -static void job_conclude(Job *job) +/* Called with job_mutex held. */ +static void job_conclude_locked(Job *job) { - job_state_transition(job, JOB_STATUS_CONCLUDED); + job_state_transition_locked(job, JOB_STATUS_CONCLUDED); if (job->auto_dismiss || !job_started(job)) { - job_do_dismiss(job); + job_do_dismiss_locked(job); } } -static void job_update_rc(Job *job) +/* Called with job_mutex held. */ +static void job_update_rc_locked(Job *job) { if (!job->ret && job_is_cancelled_locked(job)) { job->ret = -ECANCELED; @@ -781,11 +798,12 @@ static void job_update_rc(Job *job) if (!job->err) { error_setg(&job->err, "%s", strerror(-job->ret)); } - job_state_transition(job, JOB_STATUS_ABORTING); + job_state_transition_locked(job, JOB_STATUS_ABORTING); } } -static void job_commit(Job *job) +/* Called with job_mutex held, but releases it temporarly */ +static void job_commit_locked(Job *job) { assert(!job->ret); assert(qemu_in_main_thread()); @@ -796,7 +814,8 @@ static void job_commit(Job *job) } } -static void job_abort(Job *job) +/* Called with job_mutex held, but releases it temporarly */ +static void job_abort_locked(Job *job) { assert(job->ret); assert(qemu_in_main_thread()); @@ -807,7 +826,8 @@ static void job_abort(Job *job) } } -static void job_clean(Job *job) +/* Called with job_mutex held, but releases it temporarly */ +static void job_clean_locked(Job *job) { assert(qemu_in_main_thread()); if (job->driver->clean) { @@ -817,7 +837,8 @@ static void job_clean(Job *job) } } -static int job_finalize_single(Job *job) +/* Called with job_mutex held, but releases it temporarly. */ +static int job_finalize_single_locked(Job *job) { int job_ret; AioContext *ctx = job->aio_context; @@ -825,16 +846,16 @@ static int job_finalize_single(Job *job) assert(job_is_completed_locked(job)); /* Ensure abort is called for late-transactional failures */ - job_update_rc(job); + job_update_rc_locked(job); aio_context_acquire(ctx); if (!job->ret) { - job_commit(job); + job_commit_locked(job); } else { - job_abort(job); + job_abort_locked(job); } - job_clean(job); + job_clean_locked(job); aio_context_release(ctx); @@ -848,18 +869,19 @@ static int job_finalize_single(Job *job) /* Emit events only if we actually started */ if (job_started(job)) { if (job_is_cancelled_locked(job)) { - job_event_cancelled(job); + job_event_cancelled_locked(job); } else { - job_event_completed(job); + job_event_completed_locked(job); } } - job_txn_del_job(job); - job_conclude(job); + job_txn_del_job_locked(job); + job_conclude_locked(job); return 0; } -static void job_cancel_async(Job *job, bool force) +/* Called with job_mutex held, but releases it temporarly. */ +static void job_cancel_async_locked(Job *job, bool force) { assert(qemu_in_main_thread()); if (job->driver->cancel) { @@ -897,7 +919,8 @@ static void job_cancel_async(Job *job, bool force) } } -static void job_completed_txn_abort(Job *job) +/* Called with job_mutex held. */ +static void job_completed_txn_abort_locked(Job *job) { AioContext *ctx; JobTxn *txn = job->txn; @@ -910,12 +933,12 @@ static void job_completed_txn_abort(Job *job) return; } txn->aborting = true; - job_txn_ref(txn); + job_txn_ref_locked(txn); /* * We can only hold the single job's AioContext lock while calling - * job_finalize_single() because the finalization callbacks can involve - * calls of AIO_WAIT_WHILE(), which could deadlock otherwise. + * job_finalize_single_locked() because the finalization callbacks can + * involve calls of AIO_WAIT_WHILE(), which could deadlock otherwise. * Note that the job's AioContext may change when it is finalized. */ job_ref_locked(job); @@ -930,10 +953,10 @@ static void job_completed_txn_abort(Job *job) aio_context_acquire(ctx); /* * This is a transaction: If one job failed, no result will matter. - * Therefore, pass force=true to terminate all other jobs as quickly - * as possible. + * Therefore, pass force=true to terminate all other jobs as + * quickly as possible. */ - job_cancel_async(other_job, true); + job_cancel_async_locked(other_job, true); aio_context_release(ctx); } } @@ -949,13 +972,13 @@ static void job_completed_txn_abort(Job *job) assert(job_cancel_requested_locked(other_job)); job_finish_sync_locked(other_job, NULL, NULL); } - job_finalize_single(other_job); + job_finalize_single_locked(other_job); aio_context_release(ctx); } /* * Use job_ref_locked()/job_unref_locked() so we can read the AioContext - * here even if the job went away during job_finalize_single(). + * here even if the job went away during job_finalize_single_locked(). */ aio_context_acquire(job->aio_context); job_unref_locked(job); @@ -963,7 +986,8 @@ static void job_completed_txn_abort(Job *job) job_txn_unref_locked(txn); } -static int job_prepare(Job *job) +/* Called with job_mutex held, but releases it temporarly. */ +static int job_prepare_locked(Job *job) { int ret; AioContext *ctx = job->aio_context; @@ -976,28 +1000,30 @@ static int job_prepare(Job *job) aio_context_release(ctx); job_lock(); job->ret = ret; - job_update_rc(job); + job_update_rc_locked(job); } return job->ret; } -static int job_needs_finalize(Job *job) +/* Called with job_mutex held. */ +static int job_needs_finalize_locked(Job *job) { return !job->auto_finalize; } -static void job_do_finalize(Job *job) +/* Called with job_mutex held. */ +static void job_do_finalize_locked(Job *job) { int rc; assert(job && job->txn); /* prepare the transaction to complete */ - rc = job_txn_apply(job, job_prepare); + rc = job_txn_apply_locked(job, job_prepare_locked); if (rc) { - job_completed_txn_abort(job); + job_completed_txn_abort_locked(job); } else { - job_txn_apply(job, job_finalize_single); + job_txn_apply_locked(job, job_finalize_single_locked); } } @@ -1007,14 +1033,15 @@ void job_finalize_locked(Job *job, Error **errp) if (job_apply_verb_locked(job, JOB_VERB_FINALIZE, errp)) { return; } - job_do_finalize(job); + job_do_finalize_locked(job); } -static int job_transition_to_pending(Job *job) +/* Called with job_mutex held. */ +static int job_transition_to_pending_locked(Job *job) { - job_state_transition(job, JOB_STATUS_PENDING); + job_state_transition_locked(job, JOB_STATUS_PENDING); if (!job->auto_finalize) { - job_event_pending(job); + job_event_pending_locked(job); } return 0; } @@ -1022,16 +1049,17 @@ static int job_transition_to_pending(Job *job) void job_transition_to_ready(Job *job) { JOB_LOCK_GUARD(); - job_state_transition(job, JOB_STATUS_READY); - job_event_ready(job); + job_state_transition_locked(job, JOB_STATUS_READY); + job_event_ready_locked(job); } -static void job_completed_txn_success(Job *job) +/* Called with job_mutex held. */ +static void job_completed_txn_success_locked(Job *job) { JobTxn *txn = job->txn; Job *other_job; - job_state_transition(job, JOB_STATUS_WAITING); + job_state_transition_locked(job, JOB_STATUS_WAITING); /* * Successful completion, see if there are other running jobs in this @@ -1044,28 +1072,32 @@ static void job_completed_txn_success(Job *job) assert(other_job->ret == 0); } - job_txn_apply(job, job_transition_to_pending); + job_txn_apply_locked(job, job_transition_to_pending_locked); /* If no jobs need manual finalization, automatically do so */ - if (job_txn_apply(job, job_needs_finalize) == 0) { - job_do_finalize(job); + if (job_txn_apply_locked(job, job_needs_finalize_locked) == 0) { + job_do_finalize_locked(job); } } -static void job_completed(Job *job) +/* Called with job_mutex held. */ +static void job_completed_locked(Job *job) { assert(job && job->txn && !job_is_completed_locked(job)); - job_update_rc(job); + job_update_rc_locked(job); trace_job_completed(job, job->ret); if (job->ret) { - job_completed_txn_abort(job); + job_completed_txn_abort_locked(job); } else { - job_completed_txn_success(job); + job_completed_txn_success_locked(job); } } -/** Useful only as a type shim for aio_bh_schedule_oneshot. */ +/** + * Useful only as a type shim for aio_bh_schedule_oneshot. + * Called with job_mutex *not* held. + */ static void job_exit(void *opaque) { Job *job = (Job *)opaque; @@ -1080,15 +1112,15 @@ static void job_exit(void *opaque) * drain block nodes, and if .drained_poll still returned true, we would * deadlock. */ job->busy = false; - job_event_idle(job); + job_event_idle_locked(job); - job_completed(job); + job_completed_locked(job); /* - * Note that calling job_completed can move the job to a different - * aio_context, so we cannot cache from above. job_txn_apply takes care of - * acquiring the new lock, and we ref/unref to avoid job_completed freeing - * the job underneath us. + * Note that calling job_completed_locked can move the job to a different + * aio_context, so we cannot cache from above. job_txn_apply_locked takes + * care of acquiring the new lock, and we ref/unref to avoid + * job_completed_locked freeing the job underneath us. */ ctx = job->aio_context; job_unref_locked(job); @@ -1098,6 +1130,8 @@ static void job_exit(void *opaque) /** * All jobs must allow a pause point before entering their job proper. This * ensures that jobs can be paused prior to being started, then resumed later. + * + * Called with job_mutex *not* held. */ static void coroutine_fn job_co_entry(void *opaque) { @@ -1116,6 +1150,7 @@ static void coroutine_fn job_co_entry(void *opaque) aio_bh_schedule_oneshot(qemu_get_aio_context(), job_exit, job); } +/* Called with job_mutex *not* held. */ static int job_pre_run(Job *job) { assert(qemu_in_main_thread()); @@ -1140,7 +1175,7 @@ void job_start(Job *job) job->pause_count--; job->busy = true; job->paused = false; - job_state_transition(job, JOB_STATUS_RUNNING); + job_state_transition_locked(job, JOB_STATUS_RUNNING); } aio_co_enter(job->aio_context, job->co); } @@ -1148,25 +1183,25 @@ void job_start(Job *job) void job_cancel_locked(Job *job, bool force) { if (job->status == JOB_STATUS_CONCLUDED) { - job_do_dismiss(job); + job_do_dismiss_locked(job); return; } - job_cancel_async(job, force); + job_cancel_async_locked(job, force); if (!job_started(job)) { - job_completed(job); + job_completed_locked(job); } else if (job->deferred_to_main_loop) { /* - * job_cancel_async() ignores soft-cancel requests for jobs + * job_cancel_async_locked() ignores soft-cancel requests for jobs * that are already done (i.e. deferred to the main loop). We * have to check again whether the job is really cancelled. * (job_cancel_requested() and job_is_cancelled() are equivalent - * here, because job_cancel_async() will make soft-cancel + * here, because job_cancel_async_locked() will make soft-cancel * requests no-ops when deferred_to_main_loop is true. We * choose to call job_is_cancelled() to show that we invoke - * job_completed_txn_abort() only for force-cancelled jobs.) + * job_completed_txn_abort_locked() only for force-cancelled jobs.) */ if (job_is_cancelled_locked(job)) { - job_completed_txn_abort(job); + job_completed_txn_abort_locked(job); } } else { job_enter_cond_locked(job, NULL); @@ -1185,16 +1220,20 @@ void job_user_cancel_locked(Job *job, bool force, Error **errp) * A wrapper around job_cancel_locked() taking an Error ** parameter so * it may be used with job_finish_sync_locked() without the * need for (rather nasty) function pointer casts there. + * + * Called with job_mutex held. */ -static void job_cancel_err(Job *job, Error **errp) +static void job_cancel_err_locked(Job *job, Error **errp) { job_cancel_locked(job, false); } /** - * Same as job_cancel_err(), but force-cancel. + * Same as job_cancel_err_locked(), but force-cancel. + * + * Called with job_mutex held. */ -static void job_force_cancel_err(Job *job, Error **errp) +static void job_force_cancel_err_locked(Job *job, Error **errp) { job_cancel_locked(job, true); } @@ -1202,9 +1241,9 @@ static void job_force_cancel_err(Job *job, Error **errp) int job_cancel_sync_locked(Job *job, bool force) { if (force) { - return job_finish_sync_locked(job, &job_force_cancel_err, NULL); + return job_finish_sync_locked(job, &job_force_cancel_err_locked, NULL); } else { - return job_finish_sync_locked(job, &job_cancel_err, NULL); + return job_finish_sync_locked(job, &job_cancel_err_locked, NULL); } } -- 2.31.1
