2 * Rated submission helpers
4 * Copyright (C) 2015 Jens Axboe <axboe@kernel.dk>
11 #include "workqueue.h"
12 #include "lib/getrusage.h"
16 SW_F_RUNNING = 1 << 1,
19 SW_F_ACCOUNTED = 1 << 4,
23 static struct submit_worker *__get_submit_worker(struct workqueue *wq,
26 struct submit_worker **best)
28 struct submit_worker *sw = NULL;
30 while (start <= end) {
31 sw = &wq->workers[start];
32 if (sw->flags & SW_F_IDLE)
34 if (!(*best) || sw->seq < (*best)->seq)
42 static struct submit_worker *get_submit_worker(struct workqueue *wq)
44 unsigned int next = wq->next_free_worker;
45 struct submit_worker *sw, *best = NULL;
47 assert(next < wq->max_workers);
49 sw = __get_submit_worker(wq, next, wq->max_workers - 1, &best);
51 sw = __get_submit_worker(wq, 0, next - 1, &best);
54 * No truly idle found, use best match
59 if (sw->index == wq->next_free_worker) {
60 if (sw->index + 1 < wq->max_workers)
61 wq->next_free_worker = sw->index + 1;
63 wq->next_free_worker = 0;
69 static bool all_sw_idle(struct workqueue *wq)
73 for (i = 0; i < wq->max_workers; i++) {
74 struct submit_worker *sw = &wq->workers[i];
76 if (!(sw->flags & SW_F_IDLE))
84 * Must be serialized wrt workqueue_enqueue() by caller
86 void workqueue_flush(struct workqueue *wq)
90 while (!all_sw_idle(wq)) {
91 pthread_mutex_lock(&wq->flush_lock);
92 pthread_cond_wait(&wq->flush_cond, &wq->flush_lock);
93 pthread_mutex_unlock(&wq->flush_lock);
100 * Must be serialized by caller. Returns true for queued, false for busy.
102 bool workqueue_enqueue(struct workqueue *wq, struct workqueue_work *work)
104 struct submit_worker *sw;
106 sw = get_submit_worker(wq);
108 pthread_mutex_lock(&sw->lock);
109 flist_add_tail(&work->list, &sw->work_list);
110 sw->seq = ++wq->work_seq;
111 sw->flags &= ~SW_F_IDLE;
112 pthread_mutex_unlock(&sw->lock);
114 pthread_cond_signal(&sw->cond);
121 static void handle_list(struct submit_worker *sw, struct flist_head *list)
123 struct workqueue *wq = sw->wq;
124 struct workqueue_work *work;
126 while (!flist_empty(list)) {
127 work = flist_first_entry(list, struct workqueue_work, list);
128 flist_del_init(&work->list);
129 wq->ops.fn(sw, work);
133 static void *worker_thread(void *data)
135 struct submit_worker *sw = data;
136 struct workqueue *wq = sw->wq;
137 unsigned int eflags = 0, ret = 0;
138 FLIST_HEAD(local_list);
141 if (nice(wq->ops.nice) < 0) {
142 log_err("workqueue: nice %s\n", strerror(errno));
148 ret = workqueue_init_worker(sw);
150 pthread_mutex_lock(&sw->lock);
151 sw->flags |= SW_F_RUNNING;
153 sw->flags |= SW_F_ERROR;
154 pthread_mutex_unlock(&sw->lock);
156 pthread_mutex_lock(&wq->flush_lock);
157 pthread_cond_signal(&wq->flush_cond);
158 pthread_mutex_unlock(&wq->flush_lock);
160 if (sw->flags & SW_F_ERROR)
164 pthread_mutex_lock(&sw->lock);
166 if (flist_empty(&sw->work_list)) {
167 if (sw->flags & SW_F_EXIT) {
168 pthread_mutex_unlock(&sw->lock);
172 if (workqueue_pre_sleep_check(sw)) {
173 pthread_mutex_unlock(&sw->lock);
174 workqueue_pre_sleep(sw);
175 pthread_mutex_lock(&sw->lock);
179 * We dropped and reaquired the lock, check
182 if (!flist_empty(&sw->work_list))
185 if (sw->flags & SW_F_EXIT) {
186 pthread_mutex_unlock(&sw->lock);
188 } else if (!(sw->flags & SW_F_IDLE)) {
189 sw->flags |= SW_F_IDLE;
190 wq->next_free_worker = sw->index;
192 pthread_cond_signal(&wq->flush_cond);
194 if (wq->ops.update_acct_fn)
195 wq->ops.update_acct_fn(sw);
197 pthread_cond_wait(&sw->cond, &sw->lock);
200 flist_splice_init(&sw->work_list, &local_list);
202 pthread_mutex_unlock(&sw->lock);
203 handle_list(sw, &local_list);
206 if (wq->ops.update_acct_fn)
207 wq->ops.update_acct_fn(sw);
210 pthread_mutex_lock(&sw->lock);
211 sw->flags |= (SW_F_EXITED | eflags);
212 pthread_mutex_unlock(&sw->lock);
216 static void free_worker(struct submit_worker *sw, unsigned int *sum_cnt)
218 struct workqueue *wq = sw->wq;
220 workqueue_exit_worker(sw, sum_cnt);
222 pthread_cond_destroy(&sw->cond);
223 pthread_mutex_destroy(&sw->lock);
225 if (wq->ops.free_worker_fn)
226 wq->ops.free_worker_fn(sw);
229 static void shutdown_worker(struct submit_worker *sw, unsigned int *sum_cnt)
231 pthread_join(sw->thread, NULL);
232 free_worker(sw, sum_cnt);
235 void workqueue_exit(struct workqueue *wq)
237 unsigned int shutdown, sum_cnt = 0;
238 struct submit_worker *sw;
241 for (i = 0; i < wq->max_workers; i++) {
242 sw = &wq->workers[i];
244 pthread_mutex_lock(&sw->lock);
245 sw->flags |= SW_F_EXIT;
246 pthread_cond_signal(&sw->cond);
247 pthread_mutex_unlock(&sw->lock);
252 for (i = 0; i < wq->max_workers; i++) {
253 sw = &wq->workers[i];
254 if (sw->flags & SW_F_ACCOUNTED)
256 pthread_mutex_lock(&sw->lock);
257 sw->flags |= SW_F_ACCOUNTED;
258 pthread_mutex_unlock(&sw->lock);
259 shutdown_worker(sw, &sum_cnt);
262 } while (shutdown && shutdown != wq->max_workers);
265 pthread_mutex_destroy(&wq->flush_lock);
266 pthread_cond_destroy(&wq->flush_cond);
267 pthread_mutex_destroy(&wq->stat_lock);
270 static int start_worker(struct workqueue *wq, unsigned int index)
272 struct submit_worker *sw = &wq->workers[index];
275 INIT_FLIST_HEAD(&sw->work_list);
276 pthread_cond_init(&sw->cond, NULL);
277 pthread_mutex_init(&sw->lock, NULL);
281 if (wq->ops.alloc_worker_fn) {
282 ret = wq->ops.alloc_worker_fn(sw);
287 ret = pthread_create(&sw->thread, NULL, worker_thread, sw);
289 pthread_mutex_lock(&sw->lock);
290 sw->flags = SW_F_IDLE;
291 pthread_mutex_unlock(&sw->lock);
295 free_worker(sw, NULL);
299 int workqueue_init(struct thread_data *td, struct workqueue *wq,
300 struct workqueue_ops *ops, unsigned max_pending)
302 unsigned int running;
305 wq->max_workers = max_pending;
309 wq->next_free_worker = 0;
310 pthread_cond_init(&wq->flush_cond, NULL);
311 pthread_mutex_init(&wq->flush_lock, NULL);
312 pthread_mutex_init(&wq->stat_lock, NULL);
314 wq->workers = calloc(wq->max_workers, sizeof(struct submit_worker));
316 for (i = 0; i < wq->max_workers; i++)
317 if (start_worker(wq, i))
321 if (!wq->max_workers)
325 * Wait for them all to be started and initialized
329 struct submit_worker *sw;
332 pthread_mutex_lock(&wq->flush_lock);
333 for (i = 0; i < wq->max_workers; i++) {
334 sw = &wq->workers[i];
335 pthread_mutex_lock(&sw->lock);
336 if (sw->flags & SW_F_RUNNING)
338 if (sw->flags & SW_F_ERROR)
340 pthread_mutex_unlock(&sw->lock);
343 if (error || running == wq->max_workers) {
344 pthread_mutex_unlock(&wq->flush_lock);
348 pthread_cond_wait(&wq->flush_cond, &wq->flush_lock);
349 pthread_mutex_unlock(&wq->flush_lock);
356 log_err("Can't create rate workqueue\n");
357 td_verror(td, ESRCH, "workqueue_init");