| /* |
| * include/haproxy/list.h |
| * Circular list manipulation macros and functions. |
| * |
| * Copyright (C) 2002-2020 Willy Tarreau - w@1wt.eu |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation, version 2.1 |
| * exclusively. |
| * |
| * This library 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 |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #ifndef _HAPROXY_LIST_H |
| #define _HAPROXY_LIST_H |
| |
| #include <haproxy/api.h> |
| #include <haproxy/thread.h> |
| |
| /* First undefine some macros which happen to also be defined on OpenBSD, |
| * in sys/queue.h, used by sys/event.h |
| */ |
| #undef LIST_HEAD |
| #undef LIST_INIT |
| #undef LIST_NEXT |
| |
| /* ILH = Initialized List Head : used to prevent gcc from moving an empty |
| * list to BSS. Some older version tend to trim all the array and cause |
| * corruption. |
| */ |
| #define ILH { .n = (struct list *)1, .p = (struct list *)2 } |
| |
| #define LIST_HEAD(a) ((void *)(&(a))) |
| |
| #define LIST_INIT(l) ((l)->n = (l)->p = (l)) |
| |
| #define LIST_HEAD_INIT(l) { &l, &l } |
| |
| /* adds an element at the beginning of a list ; returns the element */ |
| #define LIST_INSERT(lh, el) ({ (el)->n = (lh)->n; (el)->n->p = (lh)->n = (el); (el)->p = (lh); (el); }) |
| |
| /* adds an element at the end of a list ; returns the element */ |
| #define LIST_APPEND(lh, el) ({ (el)->p = (lh)->p; (el)->p->n = (lh)->p = (el); (el)->n = (lh); (el); }) |
| |
| /* adds the contents of a list <old> at the beginning of another list <new>. The old list head remains untouched. */ |
| #define LIST_SPLICE(new, old) do { \ |
| if (!LIST_ISEMPTY(old)) { \ |
| (old)->p->n = (new)->n; (old)->n->p = (new); \ |
| (new)->n->p = (old)->p; (new)->n = (old)->n; \ |
| } \ |
| } while (0) |
| |
| /* adds the contents of a list whose first element is <old> and last one is |
| * <old->prev> at the end of another list <new>. The old list DOES NOT have |
| * any head here. |
| */ |
| #define LIST_SPLICE_END_DETACHED(new, old) do { \ |
| typeof(new) __t; \ |
| (new)->p->n = (old); \ |
| (old)->p->n = (new); \ |
| __t = (old)->p; \ |
| (old)->p = (new)->p; \ |
| (new)->p = __t; \ |
| } while (0) |
| |
| /* removes an element from a list and returns it */ |
| #define LIST_DELETE(el) ({ typeof(el) __ret = (el); (el)->n->p = (el)->p; (el)->p->n = (el)->n; (__ret); }) |
| |
| /* removes an element from a list, initializes it and returns it. |
| * This is faster than LIST_DELETE+LIST_INIT as we avoid reloading the pointers. |
| */ |
| #define LIST_DEL_INIT(el) ({ \ |
| typeof(el) __ret = (el); \ |
| typeof(__ret->n) __n = __ret->n; \ |
| typeof(__ret->p) __p = __ret->p; \ |
| __n->p = __p; __p->n = __n; \ |
| __ret->n = __ret->p = __ret; \ |
| __ret; \ |
| }) |
| |
| /* returns a pointer of type <pt> to a structure containing a list head called |
| * <el> at address <lh>. Note that <lh> can be the result of a function or macro |
| * since it's used only once. |
| * Example: LIST_ELEM(cur_node->args.next, struct node *, args) |
| */ |
| #define LIST_ELEM(lh, pt, el) ((pt)(((const char *)(lh)) - ((size_t)&((pt)NULL)->el))) |
| |
| /* checks if the list head <lh> is empty or not */ |
| #define LIST_ISEMPTY(lh) ((lh)->n == (lh)) |
| |
| /* checks if the list element <el> was added to a list or not. This only |
| * works when detached elements are reinitialized (using LIST_DEL_INIT) |
| */ |
| #define LIST_INLIST(el) ((el)->n != (el)) |
| |
| /* returns a pointer of type <pt> to a structure following the element |
| * which contains list head <lh>, which is known as element <el> in |
| * struct pt. |
| * Example: LIST_NEXT(args, struct node *, list) |
| */ |
| #define LIST_NEXT(lh, pt, el) (LIST_ELEM((lh)->n, pt, el)) |
| |
| |
| /* returns a pointer of type <pt> to a structure preceding the element |
| * which contains list head <lh>, which is known as element <el> in |
| * struct pt. |
| */ |
| #undef LIST_PREV |
| #define LIST_PREV(lh, pt, el) (LIST_ELEM((lh)->p, pt, el)) |
| |
| /* |
| * Simpler FOREACH_ITEM macro inspired from Linux sources. |
| * Iterates <item> through a list of items of type "typeof(*item)" which are |
| * linked via a "struct list" member named <member>. A pointer to the head of |
| * the list is passed in <list_head>. No temporary variable is needed. Note |
| * that <item> must not be modified during the loop. |
| * Example: list_for_each_entry(cur_acl, known_acl, list) { ... }; |
| */ |
| #define list_for_each_entry(item, list_head, member) \ |
| for (item = LIST_ELEM((list_head)->n, typeof(item), member); \ |
| &item->member != (list_head); \ |
| item = LIST_ELEM(item->member.n, typeof(item), member)) |
| |
| /* |
| * Same as list_for_each_entry but starting from current point |
| * Iterates <item> through the list starting from <item> |
| * It's basically the same macro but without initializing item to the head of |
| * the list. |
| */ |
| #define list_for_each_entry_from(item, list_head, member) \ |
| for ( ; &item->member != (list_head); \ |
| item = LIST_ELEM(item->member.n, typeof(item), member)) |
| |
| /* |
| * Simpler FOREACH_ITEM_SAFE macro inspired from Linux sources. |
| * Iterates <item> through a list of items of type "typeof(*item)" which are |
| * linked via a "struct list" member named <member>. A pointer to the head of |
| * the list is passed in <list_head>. A temporary variable <back> of same type |
| * as <item> is needed so that <item> may safely be deleted if needed. |
| * Example: list_for_each_entry_safe(cur_acl, tmp, known_acl, list) { ... }; |
| */ |
| #define list_for_each_entry_safe(item, back, list_head, member) \ |
| for (item = LIST_ELEM((list_head)->n, typeof(item), member), \ |
| back = LIST_ELEM(item->member.n, typeof(item), member); \ |
| &item->member != (list_head); \ |
| item = back, back = LIST_ELEM(back->member.n, typeof(back), member)) |
| |
| |
| /* |
| * Same as list_for_each_entry_safe but starting from current point |
| * Iterates <item> through the list starting from <item> |
| * It's basically the same macro but without initializing item to the head of |
| * the list. |
| */ |
| #define list_for_each_entry_safe_from(item, back, list_head, member) \ |
| for (back = LIST_ELEM(item->member.n, typeof(item), member); \ |
| &item->member != (list_head); \ |
| item = back, back = LIST_ELEM(back->member.n, typeof(back), member)) |
| |
| /* |
| * Iterate backwards <item> through a list of items of type "typeof(*item)" |
| * which are linked via a "struct list" member named <member>. A pointer to |
| * the head of the list is passed in <list_head>. No temporary variable is |
| * needed. Note that <item> must not be modified during the loop. |
| * Example: list_for_each_entry_rev(cur_acl, known_acl, list) { ... }; |
| */ |
| #define list_for_each_entry_rev(item, list_head, member) \ |
| for (item = LIST_ELEM((list_head)->p, typeof(item), member); \ |
| &item->member != (list_head); \ |
| item = LIST_ELEM(item->member.p, typeof(item), member)) |
| |
| /* |
| * Same as list_for_each_entry_rev but starting from current point |
| * Iterate backwards <item> through the list starting from <item> |
| * It's basically the same macro but without initializing item to the head of |
| * the list. |
| */ |
| #define list_for_each_entry_from_rev(item, list_head, member) \ |
| for ( ; &item->member != (list_head); \ |
| item = LIST_ELEM(item->member.p, typeof(item), member)) |
| |
| /* |
| * Iterate backwards <item> through a list of items of type "typeof(*item)" |
| * which are linked via a "struct list" member named <member>. A pointer to |
| * the head of the list is passed in <list_head>. A temporary variable <back> |
| * of same type as <item> is needed so that <item> may safely be deleted |
| * if needed. |
| * Example: list_for_each_entry_safe_rev(cur_acl, tmp, known_acl, list) { ... }; |
| */ |
| #define list_for_each_entry_safe_rev(item, back, list_head, member) \ |
| for (item = LIST_ELEM((list_head)->p, typeof(item), member), \ |
| back = LIST_ELEM(item->member.p, typeof(item), member); \ |
| &item->member != (list_head); \ |
| item = back, back = LIST_ELEM(back->member.p, typeof(back), member)) |
| |
| /* |
| * Same as list_for_each_entry_safe_rev but starting from current point |
| * Iterate backwards <item> through the list starting from <item> |
| * It's basically the same macro but without initializing item to the head of |
| * the list. |
| */ |
| #define list_for_each_entry_safe_from_rev(item, back, list_head, member) \ |
| for (back = LIST_ELEM(item->member.p, typeof(item), member); \ |
| &item->member != (list_head); \ |
| item = back, back = LIST_ELEM(back->member.p, typeof(back), member)) |
| |
| |
| /* |
| * Locked version of list manipulation macros. |
| * It is OK to use those concurrently from multiple threads, as long as the |
| * list is only used with the locked variants. |
| */ |
| #define MT_LIST_BUSY ((struct mt_list *)1) |
| |
| /* |
| * Add an item at the beginning of a list. |
| * Returns 1 if we added the item, 0 otherwise (because it was already in a |
| * list). |
| */ |
| #define MT_LIST_TRY_INSERT(_lh, _el) \ |
| ({ \ |
| int _ret = 0; \ |
| struct mt_list *lh = (_lh), *el = (_el); \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n, *n2; \ |
| struct mt_list *p, *p2; \ |
| n = _HA_ATOMIC_XCHG(&(lh)->next, MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) \ |
| continue; \ |
| p = _HA_ATOMIC_XCHG(&n->prev, MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) { \ |
| (lh)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| n2 = _HA_ATOMIC_XCHG(&el->next, MT_LIST_BUSY); \ |
| if (n2 != el) { /* element already linked */ \ |
| if (n2 != MT_LIST_BUSY) \ |
| el->next = n2; \ |
| n->prev = p; \ |
| __ha_barrier_store(); \ |
| lh->next = n; \ |
| __ha_barrier_store(); \ |
| if (n2 == MT_LIST_BUSY) \ |
| continue; \ |
| break; \ |
| } \ |
| p2 = _HA_ATOMIC_XCHG(&el->prev, MT_LIST_BUSY); \ |
| if (p2 != el) { \ |
| if (p2 != MT_LIST_BUSY) \ |
| el->prev = p2; \ |
| n->prev = p; \ |
| el->next = el; \ |
| __ha_barrier_store(); \ |
| lh->next = n; \ |
| __ha_barrier_store(); \ |
| if (p2 == MT_LIST_BUSY) \ |
| continue; \ |
| break; \ |
| } \ |
| (el)->next = n; \ |
| (el)->prev = p; \ |
| __ha_barrier_store(); \ |
| n->prev = (el); \ |
| __ha_barrier_store(); \ |
| p->next = (el); \ |
| __ha_barrier_store(); \ |
| _ret = 1; \ |
| break; \ |
| } \ |
| (_ret); \ |
| }) |
| |
| /* |
| * Add an item at the end of a list. |
| * Returns 1 if we added the item, 0 otherwise (because it was already in a |
| * list). |
| */ |
| #define MT_LIST_TRY_APPEND(_lh, _el) \ |
| ({ \ |
| int _ret = 0; \ |
| struct mt_list *lh = (_lh), *el = (_el); \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n, *n2; \ |
| struct mt_list *p, *p2; \ |
| p = _HA_ATOMIC_XCHG(&(lh)->prev, MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) \ |
| continue; \ |
| n = _HA_ATOMIC_XCHG(&p->next, MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) { \ |
| (lh)->prev = p; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| p2 = _HA_ATOMIC_XCHG(&el->prev, MT_LIST_BUSY); \ |
| if (p2 != el) { \ |
| if (p2 != MT_LIST_BUSY) \ |
| el->prev = p2; \ |
| p->next = n; \ |
| __ha_barrier_store(); \ |
| lh->prev = p; \ |
| __ha_barrier_store(); \ |
| if (p2 == MT_LIST_BUSY) \ |
| continue; \ |
| break; \ |
| } \ |
| n2 = _HA_ATOMIC_XCHG(&el->next, MT_LIST_BUSY); \ |
| if (n2 != el) { /* element already linked */ \ |
| if (n2 != MT_LIST_BUSY) \ |
| el->next = n2; \ |
| p->next = n; \ |
| el->prev = el; \ |
| __ha_barrier_store(); \ |
| lh->prev = p; \ |
| __ha_barrier_store(); \ |
| if (n2 == MT_LIST_BUSY) \ |
| continue; \ |
| break; \ |
| } \ |
| (el)->next = n; \ |
| (el)->prev = p; \ |
| __ha_barrier_store(); \ |
| p->next = (el); \ |
| __ha_barrier_store(); \ |
| n->prev = (el); \ |
| __ha_barrier_store(); \ |
| _ret = 1; \ |
| break; \ |
| } \ |
| (_ret); \ |
| }) |
| |
| /* |
| * Add an item at the beginning of a list. |
| * It is assumed the element can't already be in a list, so it isn't checked. |
| */ |
| #define MT_LIST_INSERT(_lh, _el) \ |
| ({ \ |
| int _ret = 0; \ |
| struct mt_list *lh = (_lh), *el = (_el); \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n; \ |
| struct mt_list *p; \ |
| n = _HA_ATOMIC_XCHG(&(lh)->next, MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) \ |
| continue; \ |
| p = _HA_ATOMIC_XCHG(&n->prev, MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) { \ |
| (lh)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| (el)->next = n; \ |
| (el)->prev = p; \ |
| __ha_barrier_store(); \ |
| n->prev = (el); \ |
| __ha_barrier_store(); \ |
| p->next = (el); \ |
| __ha_barrier_store(); \ |
| _ret = 1; \ |
| break; \ |
| } \ |
| (_ret); \ |
| }) |
| |
| /* |
| * Add an item at the end of a list. |
| * It is assumed the element can't already be in a list, so it isn't checked |
| */ |
| #define MT_LIST_APPEND(_lh, _el) \ |
| ({ \ |
| int _ret = 0; \ |
| struct mt_list *lh = (_lh), *el = (_el); \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n; \ |
| struct mt_list *p; \ |
| p = _HA_ATOMIC_XCHG(&(lh)->prev, MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) \ |
| continue; \ |
| n = _HA_ATOMIC_XCHG(&p->next, MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) { \ |
| (lh)->prev = p; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| (el)->next = n; \ |
| (el)->prev = p; \ |
| __ha_barrier_store(); \ |
| p->next = (el); \ |
| __ha_barrier_store(); \ |
| n->prev = (el); \ |
| __ha_barrier_store(); \ |
| _ret = 1; \ |
| break; \ |
| } \ |
| (_ret); \ |
| }) |
| |
| /* |
| * Detach a list from its head. A pointer to the first element is returned |
| * and the list is closed. If the list was empty, NULL is returned. This may |
| * exclusively be used with lists modified by MT_LIST_TRY_INSERT/MT_LIST_TRY_APPEND. This |
| * is incompatible with MT_LIST_DELETE run concurrently. |
| * If there's at least one element, the next of the last element will always |
| * be NULL. |
| */ |
| #define MT_LIST_BEHEAD(_lh) ({ \ |
| struct mt_list *lh = (_lh); \ |
| struct mt_list *_n; \ |
| struct mt_list *_p; \ |
| for (;;__ha_cpu_relax()) { \ |
| _p = _HA_ATOMIC_XCHG(&(lh)->prev, MT_LIST_BUSY); \ |
| if (_p == MT_LIST_BUSY) \ |
| continue; \ |
| if (_p == (lh)) { \ |
| (lh)->prev = _p; \ |
| __ha_barrier_store(); \ |
| _n = NULL; \ |
| break; \ |
| } \ |
| _n = _HA_ATOMIC_XCHG(&(lh)->next, MT_LIST_BUSY); \ |
| if (_n == MT_LIST_BUSY) { \ |
| (lh)->prev = _p; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| if (_n == (lh)) { \ |
| (lh)->next = _n; \ |
| (lh)->prev = _p; \ |
| __ha_barrier_store(); \ |
| _n = NULL; \ |
| break; \ |
| } \ |
| (lh)->next = (lh); \ |
| (lh)->prev = (lh); \ |
| __ha_barrier_store(); \ |
| _n->prev = _p; \ |
| __ha_barrier_store(); \ |
| _p->next = NULL; \ |
| __ha_barrier_store(); \ |
| break; \ |
| } \ |
| (_n); \ |
| }) |
| |
| |
| /* Remove an item from a list. |
| * Returns 1 if we removed the item, 0 otherwise (because it was in no list). |
| */ |
| #define MT_LIST_DELETE(_el) \ |
| ({ \ |
| int _ret = 0; \ |
| struct mt_list *el = (_el); \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n, *n2; \ |
| struct mt_list *p, *p2 = NULL; \ |
| n = _HA_ATOMIC_XCHG(&(el)->next, MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) \ |
| continue; \ |
| p = _HA_ATOMIC_XCHG(&(el)->prev, MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) { \ |
| (el)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| if (p != (el)) { \ |
| p2 = _HA_ATOMIC_XCHG(&p->next, MT_LIST_BUSY); \ |
| if (p2 == MT_LIST_BUSY) { \ |
| (el)->prev = p; \ |
| (el)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| } \ |
| if (n != (el)) { \ |
| n2 = _HA_ATOMIC_XCHG(&n->prev, MT_LIST_BUSY); \ |
| if (n2 == MT_LIST_BUSY) { \ |
| if (p2 != NULL) \ |
| p->next = p2; \ |
| (el)->prev = p; \ |
| (el)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| } \ |
| n->prev = p; \ |
| p->next = n; \ |
| if (p != (el) && n != (el)) \ |
| _ret = 1; \ |
| __ha_barrier_store(); \ |
| (el)->prev = (el); \ |
| (el)->next = (el); \ |
| __ha_barrier_store(); \ |
| break; \ |
| } \ |
| (_ret); \ |
| }) |
| |
| |
| /* Remove the first element from the list, and return it */ |
| #define MT_LIST_POP(_lh, pt, el) \ |
| ({ \ |
| void *_ret; \ |
| struct mt_list *lh = (_lh); \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n, *n2; \ |
| struct mt_list *p, *p2; \ |
| n = _HA_ATOMIC_XCHG(&(lh)->next, MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) \ |
| continue; \ |
| if (n == (lh)) { \ |
| (lh)->next = lh; \ |
| __ha_barrier_store(); \ |
| _ret = NULL; \ |
| break; \ |
| } \ |
| p = _HA_ATOMIC_XCHG(&n->prev, MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) { \ |
| (lh)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| n2 = _HA_ATOMIC_XCHG(&n->next, MT_LIST_BUSY); \ |
| if (n2 == MT_LIST_BUSY) { \ |
| n->prev = p; \ |
| __ha_barrier_store(); \ |
| (lh)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| p2 = _HA_ATOMIC_XCHG(&n2->prev, MT_LIST_BUSY); \ |
| if (p2 == MT_LIST_BUSY) { \ |
| n->next = n2; \ |
| n->prev = p; \ |
| __ha_barrier_store(); \ |
| (lh)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| (lh)->next = n2; \ |
| (n2)->prev = (lh); \ |
| __ha_barrier_store(); \ |
| (n)->prev = (n); \ |
| (n)->next = (n); \ |
| __ha_barrier_store(); \ |
| _ret = MT_LIST_ELEM(n, pt, el); \ |
| break; \ |
| } \ |
| (_ret); \ |
| }) |
| |
| #define MT_LIST_HEAD(a) ((void *)(&(a))) |
| |
| #define MT_LIST_INIT(l) ((l)->next = (l)->prev = (l)) |
| |
| #define MT_LIST_HEAD_INIT(l) { &l, &l } |
| /* returns a pointer of type <pt> to a structure containing a list head called |
| * <el> at address <lh>. Note that <lh> can be the result of a function or macro |
| * since it's used only once. |
| * Example: MT_LIST_ELEM(cur_node->args.next, struct node *, args) |
| */ |
| #define MT_LIST_ELEM(lh, pt, el) ((pt)(((const char *)(lh)) - ((size_t)&((pt)NULL)->el))) |
| |
| /* checks if the list head <lh> is empty or not */ |
| #define MT_LIST_ISEMPTY(lh) ((lh)->next == (lh)) |
| |
| /* returns a pointer of type <pt> to a structure following the element |
| * which contains list head <lh>, which is known as element <el> in |
| * struct pt. |
| * Example: MT_LIST_NEXT(args, struct node *, list) |
| */ |
| #define MT_LIST_NEXT(lh, pt, el) (MT_LIST_ELEM((lh)->next, pt, el)) |
| |
| |
| /* returns a pointer of type <pt> to a structure preceding the element |
| * which contains list head <lh>, which is known as element <el> in |
| * struct pt. |
| */ |
| #undef MT_LIST_PREV |
| #define MT_LIST_PREV(lh, pt, el) (MT_LIST_ELEM((lh)->prev, pt, el)) |
| |
| /* checks if the list element <el> was added to a list or not. This only |
| * works when detached elements are reinitialized (using LIST_DEL_INIT) |
| */ |
| #define MT_LIST_INLIST(el) ((el)->next != (el)) |
| |
| /* Lock an element in the list, to be sure it won't be removed. |
| * It needs to be synchronized somehow to be sure it's not removed |
| * from the list in the meanwhile. |
| * This returns a struct mt_list, that will be needed at unlock time. |
| */ |
| #define MT_LIST_LOCK_ELT(_el) \ |
| ({ \ |
| struct mt_list ret; \ |
| struct mt_liet *el = (_el); \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n, *n2; \ |
| struct mt_list *p, *p2 = NULL; \ |
| n = _HA_ATOMIC_XCHG(&(el)->next, MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) \ |
| continue; \ |
| p = _HA_ATOMIC_XCHG(&(el)->prev, MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) { \ |
| (el)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| if (p != (el)) { \ |
| p2 = _HA_ATOMIC_XCHG(&p->next, MT_LIST_BUSY);\ |
| if (p2 == MT_LIST_BUSY) { \ |
| (el)->prev = p; \ |
| (el)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| } \ |
| if (n != (el)) { \ |
| n2 = _HA_ATOMIC_XCHG(&n->prev, MT_LIST_BUSY);\ |
| if (n2 == MT_LIST_BUSY) { \ |
| if (p2 != NULL) \ |
| p->next = p2; \ |
| (el)->prev = p; \ |
| (el)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| } \ |
| ret.next = n; \ |
| ret.prev = p; \ |
| break; \ |
| } \ |
| ret; \ |
| }) |
| |
| /* Unlock an element previously locked by MT_LIST_LOCK_ELT. "np" is the |
| * struct mt_list returned by MT_LIST_LOCK_ELT(). |
| */ |
| #define MT_LIST_UNLOCK_ELT(_el, np) \ |
| do { \ |
| struct mt_list *n = (np).next, *p = (np).prev; \ |
| struct mt_list *el = (_el); \ |
| (el)->next = n; \ |
| (el)->prev = p; \ |
| if (n != (el)) \ |
| n->prev = (el); \ |
| if (p != (el)) \ |
| p->next = (el); \ |
| } while (0) |
| |
| /* Internal macroes for the foreach macroes */ |
| #define _MT_LIST_UNLOCK_NEXT(el, np) \ |
| do { \ |
| struct mt_list *n = (np); \ |
| (el)->next = n; \ |
| if (n != (el)) \ |
| n->prev = (el); \ |
| } while (0) |
| |
| /* Internal macroes for the foreach macroes */ |
| #define _MT_LIST_UNLOCK_PREV(el, np) \ |
| do { \ |
| struct mt_list *p = (np); \ |
| (el)->prev = p; \ |
| if (p != (el)) \ |
| p->next = (el); \ |
| } while (0) |
| |
| #define _MT_LIST_LOCK_NEXT(el) \ |
| ({ \ |
| struct mt_list *n = NULL; \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *n2; \ |
| n = _HA_ATOMIC_XCHG(&((el)->next), MT_LIST_BUSY); \ |
| if (n == MT_LIST_BUSY) \ |
| continue; \ |
| if (n != (el)) { \ |
| n2 = _HA_ATOMIC_XCHG(&n->prev, MT_LIST_BUSY);\ |
| if (n2 == MT_LIST_BUSY) { \ |
| (el)->next = n; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| } \ |
| break; \ |
| } \ |
| n; \ |
| }) |
| |
| #define _MT_LIST_LOCK_PREV(el) \ |
| ({ \ |
| struct mt_list *p = NULL; \ |
| for (;;__ha_cpu_relax()) { \ |
| struct mt_list *p2; \ |
| p = _HA_ATOMIC_XCHG(&((el)->prev), MT_LIST_BUSY); \ |
| if (p == MT_LIST_BUSY) \ |
| continue; \ |
| if (p != (el)) { \ |
| p2 = _HA_ATOMIC_XCHG(&p->next, MT_LIST_BUSY);\ |
| if (p2 == MT_LIST_BUSY) { \ |
| (el)->prev = p; \ |
| __ha_barrier_store(); \ |
| continue; \ |
| } \ |
| } \ |
| break; \ |
| } \ |
| p; \ |
| }) |
| |
| #define _MT_LIST_RELINK_DELETED(elt2) \ |
| do { \ |
| struct mt_list *n = elt2.next, *p = elt2.prev; \ |
| ALREADY_CHECKED(p); \ |
| n->prev = p; \ |
| p->next = n; \ |
| } while (0); |
| |
| /* Equivalent of MT_LIST_DELETE(), to be used when parsing the list with mt_list_entry_for_each_safe(). |
| * It should be the element currently parsed (tmpelt1) |
| */ |
| #define MT_LIST_DELETE_SAFE(_el) \ |
| do { \ |
| struct mt_list *el = (_el); \ |
| (el)->prev = (el); \ |
| (el)->next = (el); \ |
| (_el) = NULL; \ |
| } while (0) |
| |
| /* Safe as MT_LIST_DELETE_SAFE, but it won't reinit the element */ |
| #define MT_LIST_DELETE_SAFE_NOINIT(_el) \ |
| do { \ |
| (_el) = NULL; \ |
| } while (0) |
| |
| /* Simpler FOREACH_ITEM_SAFE macro inspired from Linux sources. |
| * Iterates <item> through a list of items of type "typeof(*item)" which are |
| * linked via a "struct list" member named <member>. A pointer to the head of |
| * the list is passed in <list_head>. A temporary variable <back> of same type |
| * as <item> is needed so that <item> may safely be deleted if needed. |
| * tmpelt1 is a temporary struct mt_list *, and tmpelt2 is a temporary |
| * struct mt_list, used internally, both are needed for MT_LIST_DELETE_SAFE. |
| * Example: list_for_each_entry_safe(cur_acl, tmp, known_acl, list, elt1, elt2) |
| * { ... }; |
| * If you want to remove the current element, please use MT_LIST_DELETE_SAFE. |
| */ |
| #define mt_list_for_each_entry_safe(item, list_head, member, tmpelt, tmpelt2) \ |
| for ((tmpelt) = NULL; (tmpelt) != MT_LIST_BUSY; ({ \ |
| if (tmpelt) { \ |
| if (tmpelt2.prev) \ |
| MT_LIST_UNLOCK_ELT(tmpelt, tmpelt2); \ |
| else \ |
| _MT_LIST_UNLOCK_NEXT(tmpelt, tmpelt2.next); \ |
| } else \ |
| _MT_LIST_RELINK_DELETED(tmpelt2); \ |
| (tmpelt) = MT_LIST_BUSY; \ |
| })) \ |
| for ((tmpelt) = (list_head), (tmpelt2).prev = NULL, (tmpelt2).next = _MT_LIST_LOCK_NEXT(tmpelt); ({ \ |
| (item) = MT_LIST_ELEM((tmpelt2.next), typeof(item), member); \ |
| if (&item->member != (list_head)) { \ |
| if (tmpelt2.prev != &item->member) \ |
| tmpelt2.next = _MT_LIST_LOCK_NEXT(&item->member); \ |
| else \ |
| tmpelt2.next = tmpelt; \ |
| if (tmpelt != NULL) { \ |
| if (tmpelt2.prev) \ |
| _MT_LIST_UNLOCK_PREV(tmpelt, tmpelt2.prev); \ |
| tmpelt2.prev = tmpelt; \ |
| } \ |
| (tmpelt) = &item->member; \ |
| } \ |
| }), \ |
| &item->member != (list_head);) |
| |
| static __inline struct list *mt_list_to_list(struct mt_list *list) |
| { |
| union { |
| struct mt_list *mt_list; |
| struct list *list; |
| } mylist; |
| |
| mylist.mt_list = list; |
| return mylist.list; |
| } |
| |
| static __inline struct mt_list *list_to_mt_list(struct list *list) |
| { |
| union { |
| struct mt_list *mt_list; |
| struct list *list; |
| } mylist; |
| |
| mylist.list = list; |
| return mylist.mt_list; |
| |
| } |
| |
| #endif /* _HAPROXY_LIST_H */ |