1#ifndef FIO_IO_U_QUEUE
2#define FIO_IO_U_QUEUE
3
4#include <assert.h>
5
6struct io_u;
7
8struct io_u_queue {
9	struct io_u **io_us;
10	unsigned int nr;
11};
12
13static inline struct io_u *io_u_qpop(struct io_u_queue *q)
14{
15	if (q->nr) {
16		const unsigned int next = --q->nr;
17		struct io_u *io_u = q->io_us[next];
18
19		q->io_us[next] = NULL;
20		return io_u;
21	}
22
23	return NULL;
24}
25
26static inline void io_u_qpush(struct io_u_queue *q, struct io_u *io_u)
27{
28	q->io_us[q->nr++] = io_u;
29}
30
31static inline int io_u_qempty(const struct io_u_queue *q)
32{
33	return !q->nr;
34}
35
36#define io_u_qiter(q, io_u, i)	\
37	for (i = 0; i < (q)->nr && (io_u = (q)->io_us[i]); i++)
38
39int io_u_qinit(struct io_u_queue *q, unsigned int nr);
40void io_u_qexit(struct io_u_queue *q);
41
42struct io_u_ring {
43	unsigned int head;
44	unsigned int tail;
45	unsigned int max;
46	struct io_u **ring;
47};
48
49int io_u_rinit(struct io_u_ring *ring, unsigned int nr);
50void io_u_rexit(struct io_u_ring *ring);
51
52static inline void io_u_rpush(struct io_u_ring *r, struct io_u *io_u)
53{
54	if (r->head + 1 != r->tail) {
55		r->ring[r->head] = io_u;
56		r->head = (r->head + 1) & (r->max - 1);
57		return;
58	}
59
60	assert(0);
61}
62
63static inline struct io_u *io_u_rpop(struct io_u_ring *r)
64{
65	if (r->head != r->tail) {
66		struct io_u *io_u = r->ring[r->tail];
67
68		r->tail = (r->tail + 1) & (r->max - 1);
69		return io_u;
70	}
71
72	return NULL;
73}
74
75static inline int io_u_rempty(struct io_u_ring *ring)
76{
77	return ring->head == ring->tail;
78}
79
80#endif
81