mirror of https://gitee.com/openkylin/linux.git
384 lines
9.9 KiB
C
384 lines
9.9 KiB
C
#ifndef _HFI1_IOWAIT_H
|
|
#define _HFI1_IOWAIT_H
|
|
/*
|
|
* Copyright(c) 2015, 2016 Intel Corporation.
|
|
*
|
|
* This file is provided under a dual BSD/GPLv2 license. When using or
|
|
* redistributing this file, you may do so under either license.
|
|
*
|
|
* GPL LICENSE SUMMARY
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of version 2 of the GNU General Public License as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* General Public License for more details.
|
|
*
|
|
* BSD LICENSE
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* - Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* - Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* - Neither the name of Intel Corporation nor the names of its
|
|
* contributors may be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
*/
|
|
|
|
#include <linux/list.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/sched.h>
|
|
|
|
#include "sdma_txreq.h"
|
|
|
|
/*
|
|
* typedef (*restart_t)() - restart callback
|
|
* @work: pointer to work structure
|
|
*/
|
|
typedef void (*restart_t)(struct work_struct *work);
|
|
|
|
struct sdma_txreq;
|
|
struct sdma_engine;
|
|
/**
|
|
* struct iowait - linkage for delayed progress/waiting
|
|
* @list: used to add/insert into QP/PQ wait lists
|
|
* @lock: uses to record the list head lock
|
|
* @tx_head: overflow list of sdma_txreq's
|
|
* @sleep: no space callback
|
|
* @wakeup: space callback wakeup
|
|
* @sdma_drained: sdma count drained
|
|
* @iowork: workqueue overhead
|
|
* @wait_dma: wait for sdma_busy == 0
|
|
* @wait_pio: wait for pio_busy == 0
|
|
* @sdma_busy: # of packets in flight
|
|
* @count: total number of descriptors in tx_head'ed list
|
|
* @tx_limit: limit for overflow queuing
|
|
* @tx_count: number of tx entry's in tx_head'ed list
|
|
*
|
|
* This is to be embedded in user's state structure
|
|
* (QP or PQ).
|
|
*
|
|
* The sleep and wakeup members are a
|
|
* bit misnamed. They do not strictly
|
|
* speaking sleep or wake up, but they
|
|
* are callbacks for the ULP to implement
|
|
* what ever queuing/dequeuing of
|
|
* the embedded iowait and its containing struct
|
|
* when a resource shortage like SDMA ring space is seen.
|
|
*
|
|
* Both potentially have locks help
|
|
* so sleeping is not allowed.
|
|
*
|
|
* The wait_dma member along with the iow
|
|
*
|
|
* The lock field is used by waiters to record
|
|
* the seqlock_t that guards the list head.
|
|
* Waiters explicity know that, but the destroy
|
|
* code that unwaits QPs does not.
|
|
*/
|
|
|
|
struct iowait {
|
|
struct list_head list;
|
|
struct list_head tx_head;
|
|
int (*sleep)(
|
|
struct sdma_engine *sde,
|
|
struct iowait *wait,
|
|
struct sdma_txreq *tx,
|
|
uint seq,
|
|
bool pkts_sent
|
|
);
|
|
void (*wakeup)(struct iowait *wait, int reason);
|
|
void (*sdma_drained)(struct iowait *wait);
|
|
seqlock_t *lock;
|
|
struct work_struct iowork;
|
|
wait_queue_head_t wait_dma;
|
|
wait_queue_head_t wait_pio;
|
|
atomic_t sdma_busy;
|
|
atomic_t pio_busy;
|
|
u32 count;
|
|
u32 tx_limit;
|
|
u32 tx_count;
|
|
u8 starved_cnt;
|
|
};
|
|
|
|
#define SDMA_AVAIL_REASON 0
|
|
|
|
/**
|
|
* iowait_init() - initialize wait structure
|
|
* @wait: wait struct to initialize
|
|
* @tx_limit: limit for overflow queuing
|
|
* @func: restart function for workqueue
|
|
* @sleep: sleep function for no space
|
|
* @resume: wakeup function for no space
|
|
*
|
|
* This function initializes the iowait
|
|
* structure embedded in the QP or PQ.
|
|
*
|
|
*/
|
|
|
|
static inline void iowait_init(
|
|
struct iowait *wait,
|
|
u32 tx_limit,
|
|
void (*func)(struct work_struct *work),
|
|
int (*sleep)(
|
|
struct sdma_engine *sde,
|
|
struct iowait *wait,
|
|
struct sdma_txreq *tx,
|
|
uint seq,
|
|
bool pkts_sent),
|
|
void (*wakeup)(struct iowait *wait, int reason),
|
|
void (*sdma_drained)(struct iowait *wait))
|
|
{
|
|
wait->count = 0;
|
|
wait->lock = NULL;
|
|
INIT_LIST_HEAD(&wait->list);
|
|
INIT_LIST_HEAD(&wait->tx_head);
|
|
INIT_WORK(&wait->iowork, func);
|
|
init_waitqueue_head(&wait->wait_dma);
|
|
init_waitqueue_head(&wait->wait_pio);
|
|
atomic_set(&wait->sdma_busy, 0);
|
|
atomic_set(&wait->pio_busy, 0);
|
|
wait->tx_limit = tx_limit;
|
|
wait->sleep = sleep;
|
|
wait->wakeup = wakeup;
|
|
wait->sdma_drained = sdma_drained;
|
|
}
|
|
|
|
/**
|
|
* iowait_schedule() - initialize wait structure
|
|
* @wait: wait struct to schedule
|
|
* @wq: workqueue for schedule
|
|
* @cpu: cpu
|
|
*/
|
|
static inline void iowait_schedule(
|
|
struct iowait *wait,
|
|
struct workqueue_struct *wq,
|
|
int cpu)
|
|
{
|
|
queue_work_on(cpu, wq, &wait->iowork);
|
|
}
|
|
|
|
/**
|
|
* iowait_sdma_drain() - wait for DMAs to drain
|
|
*
|
|
* @wait: iowait structure
|
|
*
|
|
* This will delay until the iowait sdmas have
|
|
* completed.
|
|
*/
|
|
static inline void iowait_sdma_drain(struct iowait *wait)
|
|
{
|
|
wait_event(wait->wait_dma, !atomic_read(&wait->sdma_busy));
|
|
}
|
|
|
|
/**
|
|
* iowait_sdma_pending() - return sdma pending count
|
|
*
|
|
* @wait: iowait structure
|
|
*
|
|
*/
|
|
static inline int iowait_sdma_pending(struct iowait *wait)
|
|
{
|
|
return atomic_read(&wait->sdma_busy);
|
|
}
|
|
|
|
/**
|
|
* iowait_sdma_inc - note sdma io pending
|
|
* @wait: iowait structure
|
|
*/
|
|
static inline void iowait_sdma_inc(struct iowait *wait)
|
|
{
|
|
atomic_inc(&wait->sdma_busy);
|
|
}
|
|
|
|
/**
|
|
* iowait_sdma_add - add count to pending
|
|
* @wait: iowait structure
|
|
*/
|
|
static inline void iowait_sdma_add(struct iowait *wait, int count)
|
|
{
|
|
atomic_add(count, &wait->sdma_busy);
|
|
}
|
|
|
|
/**
|
|
* iowait_sdma_dec - note sdma complete
|
|
* @wait: iowait structure
|
|
*/
|
|
static inline int iowait_sdma_dec(struct iowait *wait)
|
|
{
|
|
return atomic_dec_and_test(&wait->sdma_busy);
|
|
}
|
|
|
|
/**
|
|
* iowait_pio_drain() - wait for pios to drain
|
|
*
|
|
* @wait: iowait structure
|
|
*
|
|
* This will delay until the iowait pios have
|
|
* completed.
|
|
*/
|
|
static inline void iowait_pio_drain(struct iowait *wait)
|
|
{
|
|
wait_event_timeout(wait->wait_pio,
|
|
!atomic_read(&wait->pio_busy),
|
|
HZ);
|
|
}
|
|
|
|
/**
|
|
* iowait_pio_pending() - return pio pending count
|
|
*
|
|
* @wait: iowait structure
|
|
*
|
|
*/
|
|
static inline int iowait_pio_pending(struct iowait *wait)
|
|
{
|
|
return atomic_read(&wait->pio_busy);
|
|
}
|
|
|
|
/**
|
|
* iowait_pio_inc - note pio pending
|
|
* @wait: iowait structure
|
|
*/
|
|
static inline void iowait_pio_inc(struct iowait *wait)
|
|
{
|
|
atomic_inc(&wait->pio_busy);
|
|
}
|
|
|
|
/**
|
|
* iowait_sdma_dec - note pio complete
|
|
* @wait: iowait structure
|
|
*/
|
|
static inline int iowait_pio_dec(struct iowait *wait)
|
|
{
|
|
return atomic_dec_and_test(&wait->pio_busy);
|
|
}
|
|
|
|
/**
|
|
* iowait_drain_wakeup() - trigger iowait_drain() waiter
|
|
*
|
|
* @wait: iowait structure
|
|
*
|
|
* This will trigger any waiters.
|
|
*/
|
|
static inline void iowait_drain_wakeup(struct iowait *wait)
|
|
{
|
|
wake_up(&wait->wait_dma);
|
|
wake_up(&wait->wait_pio);
|
|
if (wait->sdma_drained)
|
|
wait->sdma_drained(wait);
|
|
}
|
|
|
|
/**
|
|
* iowait_get_txhead() - get packet off of iowait list
|
|
*
|
|
* @wait wait struture
|
|
*/
|
|
static inline struct sdma_txreq *iowait_get_txhead(struct iowait *wait)
|
|
{
|
|
struct sdma_txreq *tx = NULL;
|
|
|
|
if (!list_empty(&wait->tx_head)) {
|
|
tx = list_first_entry(
|
|
&wait->tx_head,
|
|
struct sdma_txreq,
|
|
list);
|
|
list_del_init(&tx->list);
|
|
}
|
|
return tx;
|
|
}
|
|
|
|
/**
|
|
* iowait_queue - Put the iowait on a wait queue
|
|
* @pkts_sent: have some packets been sent before queuing?
|
|
* @w: the iowait struct
|
|
* @wait_head: the wait queue
|
|
*
|
|
* This function is called to insert an iowait struct into a
|
|
* wait queue after a resource (eg, sdma decriptor or pio
|
|
* buffer) is run out.
|
|
*/
|
|
static inline void iowait_queue(bool pkts_sent, struct iowait *w,
|
|
struct list_head *wait_head)
|
|
{
|
|
/*
|
|
* To play fair, insert the iowait at the tail of the wait queue if it
|
|
* has already sent some packets; Otherwise, put it at the head.
|
|
*/
|
|
if (pkts_sent) {
|
|
list_add_tail(&w->list, wait_head);
|
|
w->starved_cnt = 0;
|
|
} else {
|
|
list_add(&w->list, wait_head);
|
|
w->starved_cnt++;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* iowait_starve_clear - clear the wait queue's starve count
|
|
* @pkts_sent: have some packets been sent?
|
|
* @w: the iowait struct
|
|
*
|
|
* This function is called to clear the starve count. If no
|
|
* packets have been sent, the starve count will not be cleared.
|
|
*/
|
|
static inline void iowait_starve_clear(bool pkts_sent, struct iowait *w)
|
|
{
|
|
if (pkts_sent)
|
|
w->starved_cnt = 0;
|
|
}
|
|
|
|
/**
|
|
* iowait_starve_find_max - Find the maximum of the starve count
|
|
* @w: the iowait struct
|
|
* @max: a variable containing the max starve count
|
|
* @idx: the index of the current iowait in an array
|
|
* @max_idx: a variable containing the array index for the
|
|
* iowait entry that has the max starve count
|
|
*
|
|
* This function is called to compare the starve count of a
|
|
* given iowait with the given max starve count. The max starve
|
|
* count and the index will be updated if the iowait's start
|
|
* count is larger.
|
|
*/
|
|
static inline void iowait_starve_find_max(struct iowait *w, u8 *max,
|
|
uint idx, uint *max_idx)
|
|
{
|
|
if (w->starved_cnt > *max) {
|
|
*max = w->starved_cnt;
|
|
*max_idx = idx;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* iowait_packet_queued() - determine if a packet is already built
|
|
* @wait: the wait structure
|
|
*/
|
|
static inline bool iowait_packet_queued(struct iowait *wait)
|
|
{
|
|
return !list_empty(&wait->tx_head);
|
|
}
|
|
|
|
#endif
|