| .. | .. |
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| 1 | 1 | #ifndef _HFI1_IOWAIT_H |
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| 2 | 2 | #define _HFI1_IOWAIT_H |
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| 3 | 3 | /* |
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| 4 | | - * Copyright(c) 2015, 2016 Intel Corporation. |
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| 4 | + * Copyright(c) 2015 - 2018 Intel Corporation. |
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| 5 | 5 | * |
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| 6 | 6 | * This file is provided under a dual BSD/GPLv2 license. When using or |
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| 7 | 7 | * redistributing this file, you may do so under either license. |
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| .. | .. |
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| 49 | 49 | |
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| 50 | 50 | #include <linux/list.h> |
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| 51 | 51 | #include <linux/workqueue.h> |
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| 52 | +#include <linux/wait.h> |
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| 52 | 53 | #include <linux/sched.h> |
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| 53 | 54 | |
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| 54 | 55 | #include "sdma_txreq.h" |
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| .. | .. |
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| 59 | 60 | */ |
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| 60 | 61 | typedef void (*restart_t)(struct work_struct *work); |
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| 61 | 62 | |
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| 63 | +#define IOWAIT_PENDING_IB 0x0 |
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| 64 | +#define IOWAIT_PENDING_TID 0x1 |
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| 65 | + |
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| 66 | +/* |
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| 67 | + * A QP can have multiple Send Engines (SEs). |
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| 68 | + * |
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| 69 | + * The current use case is for supporting a TID RDMA |
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| 70 | + * packet build/xmit mechanism independent from verbs. |
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| 71 | + */ |
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| 72 | +#define IOWAIT_SES 2 |
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| 73 | +#define IOWAIT_IB_SE 0 |
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| 74 | +#define IOWAIT_TID_SE 1 |
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| 75 | + |
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| 62 | 76 | struct sdma_txreq; |
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| 63 | 77 | struct sdma_engine; |
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| 64 | 78 | /** |
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| 65 | | - * struct iowait - linkage for delayed progress/waiting |
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| 79 | + * @iowork: the work struct |
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| 80 | + * @tx_head: list of prebuilt packets |
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| 81 | + * @iow: the parent iowait structure |
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| 82 | + * |
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| 83 | + * This structure is the work item (process) specific |
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| 84 | + * details associated with the each of the two SEs of the |
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| 85 | + * QP. |
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| 86 | + * |
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| 87 | + * The workstruct and the queued TXs are unique to each |
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| 88 | + * SE. |
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| 89 | + */ |
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| 90 | +struct iowait; |
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| 91 | +struct iowait_work { |
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| 92 | + struct work_struct iowork; |
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| 93 | + struct list_head tx_head; |
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| 94 | + struct iowait *iow; |
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| 95 | +}; |
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| 96 | + |
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| 97 | +/** |
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| 66 | 98 | * @list: used to add/insert into QP/PQ wait lists |
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| 67 | | - * @lock: uses to record the list head lock |
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| 68 | 99 | * @tx_head: overflow list of sdma_txreq's |
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| 69 | 100 | * @sleep: no space callback |
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| 70 | 101 | * @wakeup: space callback wakeup |
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| 71 | 102 | * @sdma_drained: sdma count drained |
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| 103 | + * @init_priority: callback to manipulate priority |
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| 104 | + * @lock: lock protected head of wait queue |
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| 72 | 105 | * @iowork: workqueue overhead |
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| 73 | 106 | * @wait_dma: wait for sdma_busy == 0 |
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| 74 | 107 | * @wait_pio: wait for pio_busy == 0 |
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| .. | .. |
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| 76 | 109 | * @count: total number of descriptors in tx_head'ed list |
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| 77 | 110 | * @tx_limit: limit for overflow queuing |
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| 78 | 111 | * @tx_count: number of tx entry's in tx_head'ed list |
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| 112 | + * @flags: wait flags (one per QP) |
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| 113 | + * @wait: SE array for multiple legs |
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| 79 | 114 | * |
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| 80 | 115 | * This is to be embedded in user's state structure |
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| 81 | 116 | * (QP or PQ). |
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| .. | .. |
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| 86 | 121 | * are callbacks for the ULP to implement |
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| 87 | 122 | * what ever queuing/dequeuing of |
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| 88 | 123 | * the embedded iowait and its containing struct |
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| 89 | | - * when a resource shortage like SDMA ring space is seen. |
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| 124 | + * when a resource shortage like SDMA ring space |
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| 125 | + * or PIO credit space is seen. |
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| 90 | 126 | * |
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| 91 | 127 | * Both potentially have locks help |
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| 92 | | - * so sleeping is not allowed. |
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| 128 | + * so sleeping is not allowed and it is not |
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| 129 | + * supported to submit txreqs from the wakeup |
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| 130 | + * call directly because of lock conflicts. |
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| 93 | 131 | * |
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| 94 | 132 | * The wait_dma member along with the iow |
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| 95 | 133 | * |
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| .. | .. |
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| 98 | 136 | * Waiters explicity know that, but the destroy |
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| 99 | 137 | * code that unwaits QPs does not. |
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| 100 | 138 | */ |
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| 101 | | - |
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| 102 | 139 | struct iowait { |
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| 103 | 140 | struct list_head list; |
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| 104 | | - struct list_head tx_head; |
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| 105 | 141 | int (*sleep)( |
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| 106 | 142 | struct sdma_engine *sde, |
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| 107 | | - struct iowait *wait, |
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| 143 | + struct iowait_work *wait, |
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| 108 | 144 | struct sdma_txreq *tx, |
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| 109 | 145 | uint seq, |
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| 110 | 146 | bool pkts_sent |
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| 111 | 147 | ); |
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| 112 | 148 | void (*wakeup)(struct iowait *wait, int reason); |
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| 113 | 149 | void (*sdma_drained)(struct iowait *wait); |
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| 150 | + void (*init_priority)(struct iowait *wait); |
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| 114 | 151 | seqlock_t *lock; |
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| 115 | | - struct work_struct iowork; |
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| 116 | 152 | wait_queue_head_t wait_dma; |
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| 117 | 153 | wait_queue_head_t wait_pio; |
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| 118 | 154 | atomic_t sdma_busy; |
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| .. | .. |
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| 121 | 157 | u32 tx_limit; |
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| 122 | 158 | u32 tx_count; |
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| 123 | 159 | u8 starved_cnt; |
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| 160 | + u8 priority; |
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| 161 | + unsigned long flags; |
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| 162 | + struct iowait_work wait[IOWAIT_SES]; |
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| 124 | 163 | }; |
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| 125 | 164 | |
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| 126 | 165 | #define SDMA_AVAIL_REASON 0 |
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| 127 | 166 | |
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| 128 | | -/** |
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| 129 | | - * iowait_init() - initialize wait structure |
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| 130 | | - * @wait: wait struct to initialize |
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| 131 | | - * @tx_limit: limit for overflow queuing |
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| 132 | | - * @func: restart function for workqueue |
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| 133 | | - * @sleep: sleep function for no space |
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| 134 | | - * @resume: wakeup function for no space |
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| 135 | | - * |
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| 136 | | - * This function initializes the iowait |
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| 137 | | - * structure embedded in the QP or PQ. |
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| 138 | | - * |
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| 139 | | - */ |
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| 167 | +void iowait_set_flag(struct iowait *wait, u32 flag); |
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| 168 | +bool iowait_flag_set(struct iowait *wait, u32 flag); |
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| 169 | +void iowait_clear_flag(struct iowait *wait, u32 flag); |
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| 140 | 170 | |
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| 141 | | -static inline void iowait_init( |
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| 142 | | - struct iowait *wait, |
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| 143 | | - u32 tx_limit, |
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| 144 | | - void (*func)(struct work_struct *work), |
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| 145 | | - int (*sleep)( |
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| 146 | | - struct sdma_engine *sde, |
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| 147 | | - struct iowait *wait, |
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| 148 | | - struct sdma_txreq *tx, |
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| 149 | | - uint seq, |
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| 150 | | - bool pkts_sent), |
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| 151 | | - void (*wakeup)(struct iowait *wait, int reason), |
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| 152 | | - void (*sdma_drained)(struct iowait *wait)) |
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| 153 | | -{ |
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| 154 | | - wait->count = 0; |
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| 155 | | - wait->lock = NULL; |
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| 156 | | - INIT_LIST_HEAD(&wait->list); |
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| 157 | | - INIT_LIST_HEAD(&wait->tx_head); |
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| 158 | | - INIT_WORK(&wait->iowork, func); |
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| 159 | | - init_waitqueue_head(&wait->wait_dma); |
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| 160 | | - init_waitqueue_head(&wait->wait_pio); |
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| 161 | | - atomic_set(&wait->sdma_busy, 0); |
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| 162 | | - atomic_set(&wait->pio_busy, 0); |
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| 163 | | - wait->tx_limit = tx_limit; |
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| 164 | | - wait->sleep = sleep; |
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| 165 | | - wait->wakeup = wakeup; |
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| 166 | | - wait->sdma_drained = sdma_drained; |
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| 167 | | -} |
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| 171 | +void iowait_init(struct iowait *wait, u32 tx_limit, |
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| 172 | + void (*func)(struct work_struct *work), |
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| 173 | + void (*tidfunc)(struct work_struct *work), |
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| 174 | + int (*sleep)(struct sdma_engine *sde, |
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| 175 | + struct iowait_work *wait, |
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| 176 | + struct sdma_txreq *tx, |
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| 177 | + uint seq, |
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| 178 | + bool pkts_sent), |
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| 179 | + void (*wakeup)(struct iowait *wait, int reason), |
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| 180 | + void (*sdma_drained)(struct iowait *wait), |
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| 181 | + void (*init_priority)(struct iowait *wait)); |
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| 168 | 182 | |
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| 169 | 183 | /** |
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| 170 | | - * iowait_schedule() - initialize wait structure |
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| 184 | + * iowait_schedule() - schedule the default send engine work |
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| 171 | 185 | * @wait: wait struct to schedule |
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| 172 | 186 | * @wq: workqueue for schedule |
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| 173 | 187 | * @cpu: cpu |
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| 174 | 188 | */ |
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| 175 | | -static inline void iowait_schedule( |
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| 176 | | - struct iowait *wait, |
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| 177 | | - struct workqueue_struct *wq, |
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| 178 | | - int cpu) |
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| 189 | +static inline bool iowait_schedule(struct iowait *wait, |
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| 190 | + struct workqueue_struct *wq, int cpu) |
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| 179 | 191 | { |
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| 180 | | - queue_work_on(cpu, wq, &wait->iowork); |
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| 192 | + return !!queue_work_on(cpu, wq, &wait->wait[IOWAIT_IB_SE].iowork); |
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| 193 | +} |
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| 194 | + |
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| 195 | +/** |
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| 196 | + * iowait_tid_schedule - schedule the tid SE |
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| 197 | + * @wait: the iowait structure |
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| 198 | + * @wq: the work queue |
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| 199 | + * @cpu: the cpu |
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| 200 | + */ |
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| 201 | +static inline bool iowait_tid_schedule(struct iowait *wait, |
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| 202 | + struct workqueue_struct *wq, int cpu) |
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| 203 | +{ |
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| 204 | + return !!queue_work_on(cpu, wq, &wait->wait[IOWAIT_TID_SE].iowork); |
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| 181 | 205 | } |
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| 182 | 206 | |
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| 183 | 207 | /** |
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| .. | .. |
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| 228 | 252 | */ |
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| 229 | 253 | static inline int iowait_sdma_dec(struct iowait *wait) |
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| 230 | 254 | { |
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| 255 | + if (!wait) |
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| 256 | + return 0; |
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| 231 | 257 | return atomic_dec_and_test(&wait->sdma_busy); |
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| 232 | 258 | } |
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| 233 | 259 | |
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| .. | .. |
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| 267 | 293 | } |
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| 268 | 294 | |
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| 269 | 295 | /** |
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| 270 | | - * iowait_sdma_dec - note pio complete |
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| 296 | + * iowait_pio_dec - note pio complete |
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| 271 | 297 | * @wait: iowait structure |
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| 272 | 298 | */ |
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| 273 | 299 | static inline int iowait_pio_dec(struct iowait *wait) |
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| 274 | 300 | { |
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| 301 | + if (!wait) |
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| 302 | + return 0; |
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| 275 | 303 | return atomic_dec_and_test(&wait->pio_busy); |
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| 276 | 304 | } |
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| 277 | 305 | |
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| .. | .. |
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| 293 | 321 | /** |
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| 294 | 322 | * iowait_get_txhead() - get packet off of iowait list |
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| 295 | 323 | * |
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| 296 | | - * @wait wait struture |
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| 324 | + * @wait iowait_work struture |
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| 297 | 325 | */ |
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| 298 | | -static inline struct sdma_txreq *iowait_get_txhead(struct iowait *wait) |
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| 326 | +static inline struct sdma_txreq *iowait_get_txhead(struct iowait_work *wait) |
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| 299 | 327 | { |
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| 300 | 328 | struct sdma_txreq *tx = NULL; |
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| 301 | 329 | |
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| .. | .. |
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| 309 | 337 | return tx; |
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| 310 | 338 | } |
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| 311 | 339 | |
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| 340 | +static inline u16 iowait_get_desc(struct iowait_work *w) |
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| 341 | +{ |
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| 342 | + u16 num_desc = 0; |
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| 343 | + struct sdma_txreq *tx = NULL; |
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| 344 | + |
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| 345 | + if (!list_empty(&w->tx_head)) { |
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| 346 | + tx = list_first_entry(&w->tx_head, struct sdma_txreq, |
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| 347 | + list); |
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| 348 | + num_desc = tx->num_desc; |
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| 349 | + if (tx->flags & SDMA_TXREQ_F_VIP) |
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| 350 | + w->iow->priority++; |
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| 351 | + } |
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| 352 | + return num_desc; |
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| 353 | +} |
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| 354 | + |
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| 355 | +static inline u32 iowait_get_all_desc(struct iowait *w) |
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| 356 | +{ |
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| 357 | + u32 num_desc = 0; |
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| 358 | + |
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| 359 | + num_desc = iowait_get_desc(&w->wait[IOWAIT_IB_SE]); |
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| 360 | + num_desc += iowait_get_desc(&w->wait[IOWAIT_TID_SE]); |
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| 361 | + return num_desc; |
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| 362 | +} |
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| 363 | + |
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| 364 | +static inline void iowait_update_priority(struct iowait_work *w) |
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| 365 | +{ |
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| 366 | + struct sdma_txreq *tx = NULL; |
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| 367 | + |
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| 368 | + if (!list_empty(&w->tx_head)) { |
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| 369 | + tx = list_first_entry(&w->tx_head, struct sdma_txreq, |
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| 370 | + list); |
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| 371 | + if (tx->flags & SDMA_TXREQ_F_VIP) |
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| 372 | + w->iow->priority++; |
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| 373 | + } |
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| 374 | +} |
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| 375 | + |
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| 376 | +static inline void iowait_update_all_priority(struct iowait *w) |
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| 377 | +{ |
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| 378 | + iowait_update_priority(&w->wait[IOWAIT_IB_SE]); |
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| 379 | + iowait_update_priority(&w->wait[IOWAIT_TID_SE]); |
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| 380 | +} |
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| 381 | + |
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| 382 | +static inline void iowait_init_priority(struct iowait *w) |
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| 383 | +{ |
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| 384 | + w->priority = 0; |
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| 385 | + if (w->init_priority) |
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| 386 | + w->init_priority(w); |
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| 387 | +} |
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| 388 | + |
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| 389 | +static inline void iowait_get_priority(struct iowait *w) |
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| 390 | +{ |
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| 391 | + iowait_init_priority(w); |
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| 392 | + iowait_update_all_priority(w); |
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| 393 | +} |
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| 394 | + |
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| 312 | 395 | /** |
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| 313 | 396 | * iowait_queue - Put the iowait on a wait queue |
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| 314 | 397 | * @pkts_sent: have some packets been sent before queuing? |
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| .. | .. |
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| 316 | 399 | * @wait_head: the wait queue |
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| 317 | 400 | * |
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| 318 | 401 | * This function is called to insert an iowait struct into a |
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| 319 | | - * wait queue after a resource (eg, sdma decriptor or pio |
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| 402 | + * wait queue after a resource (eg, sdma descriptor or pio |
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| 320 | 403 | * buffer) is run out. |
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| 321 | 404 | */ |
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| 322 | 405 | static inline void iowait_queue(bool pkts_sent, struct iowait *w, |
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| .. | .. |
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| 325 | 408 | /* |
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| 326 | 409 | * To play fair, insert the iowait at the tail of the wait queue if it |
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| 327 | 410 | * has already sent some packets; Otherwise, put it at the head. |
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| 411 | + * However, if it has priority packets to send, also put it at the |
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| 412 | + * head. |
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| 328 | 413 | */ |
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| 329 | | - if (pkts_sent) { |
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| 330 | | - list_add_tail(&w->list, wait_head); |
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| 414 | + if (pkts_sent) |
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| 331 | 415 | w->starved_cnt = 0; |
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| 332 | | - } else { |
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| 333 | | - list_add(&w->list, wait_head); |
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| 416 | + else |
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| 334 | 417 | w->starved_cnt++; |
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| 335 | | - } |
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| 418 | + |
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| 419 | + if (w->priority > 0 || !pkts_sent) |
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| 420 | + list_add(&w->list, wait_head); |
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| 421 | + else |
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| 422 | + list_add_tail(&w->list, wait_head); |
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| 336 | 423 | } |
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| 337 | 424 | |
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| 338 | 425 | /** |
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| .. | .. |
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| 349 | 436 | w->starved_cnt = 0; |
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| 350 | 437 | } |
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| 351 | 438 | |
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| 352 | | -/** |
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| 353 | | - * iowait_starve_find_max - Find the maximum of the starve count |
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| 354 | | - * @w: the iowait struct |
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| 355 | | - * @max: a variable containing the max starve count |
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| 356 | | - * @idx: the index of the current iowait in an array |
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| 357 | | - * @max_idx: a variable containing the array index for the |
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| 358 | | - * iowait entry that has the max starve count |
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| 359 | | - * |
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| 360 | | - * This function is called to compare the starve count of a |
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| 361 | | - * given iowait with the given max starve count. The max starve |
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| 362 | | - * count and the index will be updated if the iowait's start |
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| 363 | | - * count is larger. |
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| 364 | | - */ |
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| 365 | | -static inline void iowait_starve_find_max(struct iowait *w, u8 *max, |
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| 366 | | - uint idx, uint *max_idx) |
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| 367 | | -{ |
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| 368 | | - if (w->starved_cnt > *max) { |
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| 369 | | - *max = w->starved_cnt; |
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| 370 | | - *max_idx = idx; |
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| 371 | | - } |
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| 372 | | -} |
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| 439 | +/* Update the top priority index */ |
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| 440 | +uint iowait_priority_update_top(struct iowait *w, |
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| 441 | + struct iowait *top, |
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| 442 | + uint idx, uint top_idx); |
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| 373 | 443 | |
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| 374 | 444 | /** |
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| 375 | | - * iowait_packet_queued() - determine if a packet is already built |
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| 376 | | - * @wait: the wait structure |
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| 445 | + * iowait_packet_queued() - determine if a packet is queued |
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| 446 | + * @wait: the iowait_work structure |
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| 377 | 447 | */ |
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| 378 | | -static inline bool iowait_packet_queued(struct iowait *wait) |
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| 448 | +static inline bool iowait_packet_queued(struct iowait_work *wait) |
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| 379 | 449 | { |
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| 380 | 450 | return !list_empty(&wait->tx_head); |
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| 381 | 451 | } |
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| 382 | 452 | |
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| 453 | +/** |
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| 454 | + * inc_wait_count - increment wait counts |
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| 455 | + * @w: the log work struct |
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| 456 | + * @n: the count |
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| 457 | + */ |
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| 458 | +static inline void iowait_inc_wait_count(struct iowait_work *w, u16 n) |
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| 459 | +{ |
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| 460 | + if (!w) |
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| 461 | + return; |
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| 462 | + w->iow->tx_count++; |
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| 463 | + w->iow->count += n; |
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| 464 | +} |
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| 465 | + |
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| 466 | +/** |
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| 467 | + * iowait_get_tid_work - return iowait_work for tid SE |
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| 468 | + * @w: the iowait struct |
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| 469 | + */ |
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| 470 | +static inline struct iowait_work *iowait_get_tid_work(struct iowait *w) |
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| 471 | +{ |
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| 472 | + return &w->wait[IOWAIT_TID_SE]; |
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| 473 | +} |
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| 474 | + |
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| 475 | +/** |
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| 476 | + * iowait_get_ib_work - return iowait_work for ib SE |
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| 477 | + * @w: the iowait struct |
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| 478 | + */ |
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| 479 | +static inline struct iowait_work *iowait_get_ib_work(struct iowait *w) |
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| 480 | +{ |
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| 481 | + return &w->wait[IOWAIT_IB_SE]; |
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| 482 | +} |
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| 483 | + |
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| 484 | +/** |
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| 485 | + * iowait_ioww_to_iow - return iowait given iowait_work |
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| 486 | + * @w: the iowait_work struct |
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| 487 | + */ |
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| 488 | +static inline struct iowait *iowait_ioww_to_iow(struct iowait_work *w) |
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| 489 | +{ |
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| 490 | + if (likely(w)) |
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| 491 | + return w->iow; |
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| 492 | + return NULL; |
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| 493 | +} |
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| 494 | + |
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| 495 | +void iowait_cancel_work(struct iowait *w); |
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| 496 | +int iowait_set_work_flag(struct iowait_work *w); |
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| 497 | + |
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| 383 | 498 | #endif |
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