mars/kernel/lib_queue.h
2014-11-25 18:09:17 +01:00

173 lines
5.0 KiB
C

/*
* MARS Long Distance Replication Software
*
* This file is part of MARS project: http://schoebel.github.io/mars/
*
* Copyright (C) 2010-2014 Thomas Schoebel-Theuer
* Copyright (C) 2011-2014 1&1 Internet AG
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef LIB_QUEUE_H
#define LIB_QUEUE_H
#define QUEUE_ANCHOR(PREFIX,KEYTYPE,HEAPTYPE) \
/* parameters */ \
/* readonly from outside */ \
atomic_t q_queued; \
atomic_t q_flying; \
atomic_t q_total; \
/* tunables */ \
int q_batchlen; \
int q_io_prio; \
bool q_ordering; \
/* private */ \
wait_queue_head_t *q_event; \
spinlock_t q_lock; \
struct list_head q_anchor; \
struct pairing_heap_##HEAPTYPE *heap_high; \
struct pairing_heap_##HEAPTYPE *heap_low; \
long long q_last_insert; /* jiffies */ \
KEYTYPE heap_margin; \
KEYTYPE last_pos; \
#define QUEUE_FUNCTIONS(PREFIX,ELEM_TYPE,HEAD,KEYFN,KEYCMP,HEAPTYPE) \
\
static inline \
void q_##PREFIX##_trigger(struct PREFIX##_queue *q) \
{ \
if (q->q_event) { \
wake_up_interruptible(q->q_event); \
} \
} \
\
static inline \
void q_##PREFIX##_init(struct PREFIX##_queue *q) \
{ \
INIT_LIST_HEAD(&q->q_anchor); \
q->heap_low = NULL; \
q->heap_high = NULL; \
spin_lock_init(&q->q_lock); \
atomic_set(&q->q_queued, 0); \
atomic_set(&q->q_flying, 0); \
} \
\
static inline \
void q_##PREFIX##_insert(struct PREFIX##_queue *q, ELEM_TYPE *elem) \
{ \
unsigned long flags; \
\
traced_lock(&q->q_lock, flags); \
\
if (q->q_ordering) { \
struct pairing_heap_##HEAPTYPE **use = &q->heap_high; \
if (KEYCMP(KEYFN(elem), &q->heap_margin) <= 0) { \
use = &q->heap_low; \
} \
ph_insert_##HEAPTYPE(use, &elem->ph); \
} else { \
list_add_tail(&elem->HEAD, &q->q_anchor); \
} \
atomic_inc(&q->q_queued); \
atomic_inc(&q->q_total); \
q->q_last_insert = jiffies; \
\
traced_unlock(&q->q_lock, flags); \
\
q_##PREFIX##_trigger(q); \
} \
\
static inline \
void q_##PREFIX##_pushback(struct PREFIX##_queue *q, ELEM_TYPE *elem) \
{ \
unsigned long flags; \
\
if (q->q_ordering) { \
atomic_dec(&q->q_total); \
q_##PREFIX##_insert(q, elem); \
return; \
} \
\
traced_lock(&q->q_lock, flags); \
\
list_add(&elem->HEAD, &q->q_anchor); \
atomic_inc(&q->q_queued); \
\
traced_unlock(&q->q_lock, flags); \
} \
\
static inline \
ELEM_TYPE *q_##PREFIX##_fetch(struct PREFIX##_queue *q) \
{ \
ELEM_TYPE *elem = NULL; \
unsigned long flags; \
\
traced_lock(&q->q_lock, flags); \
\
if (q->q_ordering) { \
if (!q->heap_high) { \
q->heap_high = q->heap_low; \
q->heap_low = NULL; \
q->heap_margin = 0; \
q->last_pos = 0; \
} \
if (q->heap_high) { \
elem = container_of(q->heap_high, ELEM_TYPE, ph); \
\
if (unlikely(KEYCMP(KEYFN(elem), &q->last_pos) < 0)) { \
MARS_ERR("backskip pos %lld -> %lld\n", (long long)q->last_pos, (long long)KEYFN(elem)); \
} \
memcpy(&q->last_pos, KEYFN(elem), sizeof(q->last_pos)); \
\
if (KEYCMP(KEYFN(elem), &q->heap_margin) > 0) { \
memcpy(&q->heap_margin, KEYFN(elem), sizeof(q->heap_margin)); \
} \
ph_delete_min_##HEAPTYPE(&q->heap_high); \
atomic_dec(&q->q_queued); \
} \
} else if (!list_empty(&q->q_anchor)) { \
struct list_head *next = q->q_anchor.next; \
list_del_init(next); \
atomic_dec(&q->q_queued); \
elem = container_of(next, ELEM_TYPE, HEAD); \
} \
\
traced_unlock(&q->q_lock, flags); \
\
q_##PREFIX##_trigger(q); \
\
return elem; \
} \
\
static inline \
void q_##PREFIX##_inc_flying(struct PREFIX##_queue *q) \
{ \
atomic_inc(&q->q_flying); \
q_##PREFIX##_trigger(q); \
} \
\
static inline \
void q_##PREFIX##_dec_flying(struct PREFIX##_queue *q) \
{ \
atomic_dec(&q->q_flying); \
q_##PREFIX##_trigger(q); \
} \
\
#endif