freebsd-nq/sys/contrib/ck/include/ck_queue.h
Andriy Gapon 725de58112 MFV CK@r336629: Import CK as of commit 1c1f9901c2dea7a883342cd03d3906a1bc482583
This adds CK_SLIST_INSERT_PREVPTR and CK_SLIST_REMOVE_PREVPTR macros
as well as ck_pr_dec_is_zero family of functions.

MFC after:	3 weeks
2018-07-23 11:21:43 +00:00

439 lines
16 KiB
C

/*
* Copyright 2012-2015 Samy Al Bahra.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)queue.h 8.5 (Berkeley) 8/20/94
* $FreeBSD$
*/
#ifndef CK_QUEUE_H
#define CK_QUEUE_H
#include <ck_pr.h>
/*
* This file defines three types of data structures: singly-linked lists,
* singly-linked tail queues and lists.
*
* A singly-linked list is headed by a single forward pointer. The elements
* are singly linked for minimum space and pointer manipulation overhead at
* the expense of O(n) removal for arbitrary elements. New elements can be
* added to the list after an existing element or at the head of the list.
* Elements being removed from the head of the list should use the explicit
* macro for this purpose for optimum efficiency. A singly-linked list may
* only be traversed in the forward direction. Singly-linked lists are ideal
* for applications with large datasets and few or no removals or for
* implementing a LIFO queue.
*
* A singly-linked tail queue is headed by a pair of pointers, one to the
* head of the list and the other to the tail of the list. The elements are
* singly linked for minimum space and pointer manipulation overhead at the
* expense of O(n) removal for arbitrary elements. New elements can be added
* to the list after an existing element, at the head of the list, or at the
* end of the list. Elements being removed from the head of the tail queue
* should use the explicit macro for this purpose for optimum efficiency.
* A singly-linked tail queue may only be traversed in the forward direction.
* Singly-linked tail queues are ideal for applications with large datasets
* and few or no removals or for implementing a FIFO queue.
*
* A list is headed by a single forward pointer (or an array of forward
* pointers for a hash table header). The elements are doubly linked
* so that an arbitrary element can be removed without a need to
* traverse the list. New elements can be added to the list before
* or after an existing element or at the head of the list. A list
* may only be traversed in the forward direction.
*
* It is safe to use _FOREACH/_FOREACH_SAFE in the presence of concurrent
* modifications to the list. Writers to these lists must, on the other hand,
* implement writer-side synchronization. The _SWAP operations are not atomic.
* This facility is currently unsupported on architectures such as the Alpha
* which require load-depend memory fences.
*
* CK_SLIST CK_LIST CK_STAILQ
* _HEAD + + +
* _HEAD_INITIALIZER + + +
* _ENTRY + + +
* _INIT + + +
* _EMPTY + + +
* _FIRST + + +
* _NEXT + + +
* _FOREACH + + +
* _FOREACH_SAFE + + +
* _INSERT_HEAD + + +
* _INSERT_BEFORE - + -
* _INSERT_AFTER + + +
* _INSERT_TAIL - - +
* _REMOVE_AFTER + - +
* _REMOVE_HEAD + - +
* _REMOVE + + +
* _SWAP + + +
* _MOVE + + +
*/
/*
* Singly-linked List declarations.
*/
#define CK_SLIST_HEAD(name, type) \
struct name { \
struct type *cslh_first; /* first element */ \
}
#define CK_SLIST_HEAD_INITIALIZER(head) \
{ NULL }
#define CK_SLIST_ENTRY(type) \
struct { \
struct type *csle_next; /* next element */ \
}
/*
* Singly-linked List functions.
*/
#define CK_SLIST_EMPTY(head) \
(ck_pr_load_ptr(&(head)->cslh_first) == NULL)
#define CK_SLIST_FIRST(head) \
(ck_pr_load_ptr(&(head)->cslh_first))
#define CK_SLIST_NEXT(elm, field) \
ck_pr_load_ptr(&((elm)->field.csle_next))
#define CK_SLIST_FOREACH(var, head, field) \
for ((var) = CK_SLIST_FIRST((head)); \
(var) && (ck_pr_fence_load(), 1); \
(var) = CK_SLIST_NEXT((var), field))
#define CK_SLIST_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = CK_SLIST_FIRST(head); \
(var) && (ck_pr_fence_load(), (tvar) = CK_SLIST_NEXT(var, field), 1);\
(var) = (tvar))
#define CK_SLIST_FOREACH_PREVPTR(var, varp, head, field) \
for ((varp) = &(head)->cslh_first; \
((var) = ck_pr_load_ptr(varp)) != NULL && (ck_pr_fence_load(), 1); \
(varp) = &(var)->field.csle_next)
#define CK_SLIST_INIT(head) do { \
ck_pr_store_ptr(&(head)->cslh_first, NULL); \
ck_pr_fence_store(); \
} while (0)
#define CK_SLIST_INSERT_AFTER(a, b, field) do { \
(b)->field.csle_next = (a)->field.csle_next; \
ck_pr_fence_store(); \
ck_pr_store_ptr(&(a)->field.csle_next, b); \
} while (0)
#define CK_SLIST_INSERT_HEAD(head, elm, field) do { \
(elm)->field.csle_next = (head)->cslh_first; \
ck_pr_fence_store(); \
ck_pr_store_ptr(&(head)->cslh_first, elm); \
} while (0)
#define CK_SLIST_INSERT_PREVPTR(prevp, slistelm, elm, field) do { \
(elm)->field.csle_next = (slistelm); \
ck_pr_fence_store(); \
ck_pr_store_ptr(prevp, elm); \
} while (0)
#define CK_SLIST_REMOVE_AFTER(elm, field) do { \
ck_pr_store_ptr(&(elm)->field.csle_next, \
(elm)->field.csle_next->field.csle_next); \
} while (0)
#define CK_SLIST_REMOVE(head, elm, type, field) do { \
if ((head)->cslh_first == (elm)) { \
CK_SLIST_REMOVE_HEAD((head), field); \
} else { \
struct type *curelm = (head)->cslh_first; \
while (curelm->field.csle_next != (elm)) \
curelm = curelm->field.csle_next; \
CK_SLIST_REMOVE_AFTER(curelm, field); \
} \
} while (0)
#define CK_SLIST_REMOVE_HEAD(head, field) do { \
ck_pr_store_ptr(&(head)->cslh_first, \
(head)->cslh_first->field.csle_next); \
} while (0)
#define CK_SLIST_REMOVE_PREVPTR(prevp, elm, field) do { \
ck_pr_store_ptr(prevptr, (elm)->field.csle_next); \
} while (0)
#define CK_SLIST_MOVE(head1, head2, field) do { \
ck_pr_store_ptr(&(head1)->cslh_first, (head2)->cslh_first); \
} while (0)
/*
* This operation is not applied atomically.
*/
#define CK_SLIST_SWAP(a, b, type) do { \
struct type *swap_first = (a)->cslh_first; \
(a)->cslh_first = (b)->cslh_first; \
(b)->cslh_first = swap_first; \
} while (0)
/*
* Singly-linked Tail queue declarations.
*/
#define CK_STAILQ_HEAD(name, type) \
struct name { \
struct type *cstqh_first;/* first element */ \
struct type **cstqh_last;/* addr of last next element */ \
}
#define CK_STAILQ_HEAD_INITIALIZER(head) \
{ NULL, &(head).cstqh_first }
#define CK_STAILQ_ENTRY(type) \
struct { \
struct type *cstqe_next; /* next element */ \
}
/*
* Singly-linked Tail queue functions.
*/
#define CK_STAILQ_CONCAT(head1, head2) do { \
if ((head2)->cstqh_first != NULL) { \
ck_pr_store_ptr((head1)->cstqh_last, (head2)->cstqh_first); \
ck_pr_fence_store(); \
(head1)->cstqh_last = (head2)->cstqh_last; \
CK_STAILQ_INIT((head2)); \
} \
} while (0)
#define CK_STAILQ_EMPTY(head) (ck_pr_load_ptr(&(head)->cstqh_first) == NULL)
#define CK_STAILQ_FIRST(head) (ck_pr_load_ptr(&(head)->cstqh_first))
#define CK_STAILQ_FOREACH(var, head, field) \
for((var) = CK_STAILQ_FIRST((head)); \
(var) && (ck_pr_fence_load(), 1); \
(var) = CK_STAILQ_NEXT((var), field))
#define CK_STAILQ_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = CK_STAILQ_FIRST((head)); \
(var) && (ck_pr_fence_load(), (tvar) = \
CK_STAILQ_NEXT((var), field), 1); \
(var) = (tvar))
#define CK_STAILQ_INIT(head) do { \
ck_pr_store_ptr(&(head)->cstqh_first, NULL); \
ck_pr_fence_store(); \
(head)->cstqh_last = &(head)->cstqh_first; \
} while (0)
#define CK_STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \
(elm)->field.cstqe_next = (tqelm)->field.cstqe_next; \
ck_pr_fence_store(); \
ck_pr_store_ptr(&(tqelm)->field.cstqe_next, elm); \
if ((elm)->field.cstqe_next == NULL) \
(head)->cstqh_last = &(elm)->field.cstqe_next; \
} while (0)
#define CK_STAILQ_INSERT_HEAD(head, elm, field) do { \
(elm)->field.cstqe_next = (head)->cstqh_first; \
ck_pr_fence_store(); \
ck_pr_store_ptr(&(head)->cstqh_first, elm); \
if ((elm)->field.cstqe_next == NULL) \
(head)->cstqh_last = &(elm)->field.cstqe_next; \
} while (0)
#define CK_STAILQ_INSERT_TAIL(head, elm, field) do { \
(elm)->field.cstqe_next = NULL; \
ck_pr_fence_store(); \
ck_pr_store_ptr((head)->cstqh_last, (elm)); \
(head)->cstqh_last = &(elm)->field.cstqe_next; \
} while (0)
#define CK_STAILQ_NEXT(elm, field) \
(ck_pr_load_ptr(&(elm)->field.cstqe_next))
#define CK_STAILQ_REMOVE(head, elm, type, field) do { \
if ((head)->cstqh_first == (elm)) { \
CK_STAILQ_REMOVE_HEAD((head), field); \
} else { \
struct type *curelm = (head)->cstqh_first; \
while (curelm->field.cstqe_next != (elm)) \
curelm = curelm->field.cstqe_next; \
CK_STAILQ_REMOVE_AFTER(head, curelm, field); \
} \
} while (0)
#define CK_STAILQ_REMOVE_AFTER(head, elm, field) do { \
ck_pr_store_ptr(&(elm)->field.cstqe_next, \
(elm)->field.cstqe_next->field.cstqe_next); \
if ((elm)->field.cstqe_next == NULL) \
(head)->cstqh_last = &(elm)->field.cstqe_next; \
} while (0)
#define CK_STAILQ_REMOVE_HEAD(head, field) do { \
ck_pr_store_ptr(&(head)->cstqh_first, \
(head)->cstqh_first->field.cstqe_next); \
if ((head)->cstqh_first == NULL) \
(head)->cstqh_last = &(head)->cstqh_first; \
} while (0)
#define CK_STAILQ_MOVE(head1, head2, field) do { \
ck_pr_store_ptr(&(head1)->cstqh_first, (head2)->cstqh_first); \
(head1)->cstqh_last = (head2)->cstqh_last; \
if ((head2)->cstqh_last == &(head2)->cstqh_first) \
(head1)->cstqh_last = &(head1)->cstqh_first; \
} while (0)
/*
* This operation is not applied atomically.
*/
#define CK_STAILQ_SWAP(head1, head2, type) do { \
struct type *swap_first = CK_STAILQ_FIRST(head1); \
struct type **swap_last = (head1)->cstqh_last; \
CK_STAILQ_FIRST(head1) = CK_STAILQ_FIRST(head2); \
(head1)->cstqh_last = (head2)->cstqh_last; \
CK_STAILQ_FIRST(head2) = swap_first; \
(head2)->cstqh_last = swap_last; \
if (CK_STAILQ_EMPTY(head1)) \
(head1)->cstqh_last = &(head1)->cstqh_first; \
if (CK_STAILQ_EMPTY(head2)) \
(head2)->cstqh_last = &(head2)->cstqh_first; \
} while (0)
/*
* List declarations.
*/
#define CK_LIST_HEAD(name, type) \
struct name { \
struct type *clh_first; /* first element */ \
}
#define CK_LIST_HEAD_INITIALIZER(head) \
{ NULL }
#define CK_LIST_ENTRY(type) \
struct { \
struct type *cle_next; /* next element */ \
struct type **cle_prev; /* address of previous next element */ \
}
#define CK_LIST_FIRST(head) ck_pr_load_ptr(&(head)->clh_first)
#define CK_LIST_EMPTY(head) (CK_LIST_FIRST(head) == NULL)
#define CK_LIST_NEXT(elm, field) ck_pr_load_ptr(&(elm)->field.cle_next)
#define CK_LIST_FOREACH(var, head, field) \
for ((var) = CK_LIST_FIRST((head)); \
(var) && (ck_pr_fence_load(), 1); \
(var) = CK_LIST_NEXT((var), field))
#define CK_LIST_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = CK_LIST_FIRST((head)); \
(var) && (ck_pr_fence_load(), (tvar) = CK_LIST_NEXT((var), field), 1);\
(var) = (tvar))
#define CK_LIST_INIT(head) do { \
ck_pr_store_ptr(&(head)->clh_first, NULL); \
ck_pr_fence_store(); \
} while (0)
#define CK_LIST_INSERT_AFTER(listelm, elm, field) do { \
(elm)->field.cle_next = (listelm)->field.cle_next; \
(elm)->field.cle_prev = &(listelm)->field.cle_next; \
ck_pr_fence_store(); \
if ((listelm)->field.cle_next != NULL) \
(listelm)->field.cle_next->field.cle_prev = &(elm)->field.cle_next;\
ck_pr_store_ptr(&(listelm)->field.cle_next, elm); \
} while (0)
#define CK_LIST_INSERT_BEFORE(listelm, elm, field) do { \
(elm)->field.cle_prev = (listelm)->field.cle_prev; \
(elm)->field.cle_next = (listelm); \
ck_pr_fence_store(); \
ck_pr_store_ptr((listelm)->field.cle_prev, (elm)); \
(listelm)->field.cle_prev = &(elm)->field.cle_next; \
} while (0)
#define CK_LIST_INSERT_HEAD(head, elm, field) do { \
(elm)->field.cle_next = (head)->clh_first; \
ck_pr_fence_store(); \
if ((elm)->field.cle_next != NULL) \
(head)->clh_first->field.cle_prev = &(elm)->field.cle_next; \
ck_pr_store_ptr(&(head)->clh_first, elm); \
(elm)->field.cle_prev = &(head)->clh_first; \
} while (0)
#define CK_LIST_REMOVE(elm, field) do { \
ck_pr_store_ptr((elm)->field.cle_prev, (elm)->field.cle_next); \
if ((elm)->field.cle_next != NULL) \
(elm)->field.cle_next->field.cle_prev = (elm)->field.cle_prev; \
} while (0)
#define CK_LIST_MOVE(head1, head2, field) do { \
ck_pr_store_ptr(&(head1)->clh_first, (head2)->clh_first); \
if ((head1)->clh_first != NULL) \
(head1)->clh_first->field.cle_prev = &(head1)->clh_first; \
} while (0)
/*
* This operation is not applied atomically.
*/
#define CK_LIST_SWAP(head1, head2, type, field) do { \
struct type *swap_tmp = (head1)->clh_first; \
(head1)->clh_first = (head2)->clh_first; \
(head2)->clh_first = swap_tmp; \
if ((swap_tmp = (head1)->clh_first) != NULL) \
swap_tmp->field.cle_prev = &(head1)->clh_first; \
if ((swap_tmp = (head2)->clh_first) != NULL) \
swap_tmp->field.cle_prev = &(head2)->clh_first; \
} while (0)
#endif /* CK_QUEUE_H */