1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /*
3 * Copyright(c) 2018 Intel Corporation.
4 *
5 */
6 #include "iowait.h"
7 #include "trace_iowait.h"
8
9 /* 1 priority == 16 starve_cnt */
10 #define IOWAIT_PRIORITY_STARVE_SHIFT 4
11
iowait_set_flag(struct iowait * wait,u32 flag)12 void iowait_set_flag(struct iowait *wait, u32 flag)
13 {
14 trace_hfi1_iowait_set(wait, flag);
15 set_bit(flag, &wait->flags);
16 }
17
iowait_flag_set(struct iowait * wait,u32 flag)18 bool iowait_flag_set(struct iowait *wait, u32 flag)
19 {
20 return test_bit(flag, &wait->flags);
21 }
22
iowait_clear_flag(struct iowait * wait,u32 flag)23 inline void iowait_clear_flag(struct iowait *wait, u32 flag)
24 {
25 trace_hfi1_iowait_clear(wait, flag);
26 clear_bit(flag, &wait->flags);
27 }
28
29 /**
30 * iowait_init() - initialize wait structure
31 * @wait: wait struct to initialize
32 * @tx_limit: limit for overflow queuing
33 * @func: restart function for workqueue
34 * @sleep: sleep function for no space
35 * @resume: wakeup function for no space
36 *
37 * This function initializes the iowait
38 * structure embedded in the QP or PQ.
39 *
40 */
iowait_init(struct iowait * wait,u32 tx_limit,void (* func)(struct work_struct * work),void (* tidfunc)(struct work_struct * work),int (* sleep)(struct sdma_engine * sde,struct iowait_work * wait,struct sdma_txreq * tx,uint seq,bool pkts_sent),void (* wakeup)(struct iowait * wait,int reason),void (* sdma_drained)(struct iowait * wait),void (* init_priority)(struct iowait * wait))41 void iowait_init(struct iowait *wait, u32 tx_limit,
42 void (*func)(struct work_struct *work),
43 void (*tidfunc)(struct work_struct *work),
44 int (*sleep)(struct sdma_engine *sde,
45 struct iowait_work *wait,
46 struct sdma_txreq *tx,
47 uint seq,
48 bool pkts_sent),
49 void (*wakeup)(struct iowait *wait, int reason),
50 void (*sdma_drained)(struct iowait *wait),
51 void (*init_priority)(struct iowait *wait))
52 {
53 int i;
54
55 wait->count = 0;
56 INIT_LIST_HEAD(&wait->list);
57 init_waitqueue_head(&wait->wait_dma);
58 init_waitqueue_head(&wait->wait_pio);
59 atomic_set(&wait->sdma_busy, 0);
60 atomic_set(&wait->pio_busy, 0);
61 wait->tx_limit = tx_limit;
62 wait->sleep = sleep;
63 wait->wakeup = wakeup;
64 wait->sdma_drained = sdma_drained;
65 wait->init_priority = init_priority;
66 wait->flags = 0;
67 for (i = 0; i < IOWAIT_SES; i++) {
68 wait->wait[i].iow = wait;
69 INIT_LIST_HEAD(&wait->wait[i].tx_head);
70 if (i == IOWAIT_IB_SE)
71 INIT_WORK(&wait->wait[i].iowork, func);
72 else
73 INIT_WORK(&wait->wait[i].iowork, tidfunc);
74 }
75 }
76
77 /**
78 * iowait_cancel_work - cancel all work in iowait
79 * @w: the iowait struct
80 */
iowait_cancel_work(struct iowait * w)81 void iowait_cancel_work(struct iowait *w)
82 {
83 cancel_work_sync(&iowait_get_ib_work(w)->iowork);
84 cancel_work_sync(&iowait_get_tid_work(w)->iowork);
85 }
86
87 /**
88 * iowait_set_work_flag - set work flag based on leg
89 * @w - the iowait work struct
90 */
iowait_set_work_flag(struct iowait_work * w)91 int iowait_set_work_flag(struct iowait_work *w)
92 {
93 if (w == &w->iow->wait[IOWAIT_IB_SE]) {
94 iowait_set_flag(w->iow, IOWAIT_PENDING_IB);
95 return IOWAIT_IB_SE;
96 }
97 iowait_set_flag(w->iow, IOWAIT_PENDING_TID);
98 return IOWAIT_TID_SE;
99 }
100
101 /**
102 * iowait_priority_update_top - update the top priority entry
103 * @w: the iowait struct
104 * @top: a pointer to the top priority entry
105 * @idx: the index of the current iowait in an array
106 * @top_idx: the array index for the iowait entry that has the top priority
107 *
108 * This function is called to compare the priority of a given
109 * iowait with the given top priority entry. The top index will
110 * be returned.
111 */
iowait_priority_update_top(struct iowait * w,struct iowait * top,uint idx,uint top_idx)112 uint iowait_priority_update_top(struct iowait *w,
113 struct iowait *top,
114 uint idx, uint top_idx)
115 {
116 u8 cnt, tcnt;
117
118 /* Convert priority into starve_cnt and compare the total.*/
119 cnt = (w->priority << IOWAIT_PRIORITY_STARVE_SHIFT) + w->starved_cnt;
120 tcnt = (top->priority << IOWAIT_PRIORITY_STARVE_SHIFT) +
121 top->starved_cnt;
122 if (cnt > tcnt)
123 return idx;
124 else
125 return top_idx;
126 }
127
