1c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/* 2c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Descending-priority-sorted double-linked list 3c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 4c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * (C) 2002-2003 Intel Corp 5c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>. 6c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 7c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 2001-2005 (c) MontaVista Software, Inc. 8c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Daniel Walker <dwalker@mvista.com> 9c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 10c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * (C) 2005 Thomas Gleixner <tglx@linutronix.de> 11c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 12c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Simplifications of the original code by 13c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Oleg Nesterov <oleg@tv-sign.ru> 14c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 15c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Licensed under the FSF's GNU Public License v2 or later. 16c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 17c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Based on simple lists (include/linux/list.h). 18c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 19c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * This is a priority-sorted list of nodes; each node has a 20c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * priority from INT_MIN (highest) to INT_MAX (lowest). 21c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 22c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Addition is O(K), removal is O(1), change of priority of a node is 23c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * O(K) and K is the number of RT priority levels used in the system. 24c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * (1 <= K <= 99) 25c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 26c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * This list is really a list of lists: 27c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 28c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * - The tier 1 list is the prio_list, different priority nodes. 29c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 30c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * - The tier 2 list is the node_list, serialized nodes. 31c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 32c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Simple ASCII art explanation: 33c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 34c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * |HEAD | 35c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * | | 36c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * |prio_list.prev|<------------------------------------| 37c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * |prio_list.next|<->|pl|<->|pl|<--------------->|pl|<-| 38c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * |10 | |10| |21| |21| |21| |40| (prio) 39c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * | | | | | | | | | | | | 40c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * | | | | | | | | | | | | 41c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * |node_list.next|<->|nl|<->|nl|<->|nl|<->|nl|<->|nl|<-| 42c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * |node_list.prev|<------------------------------------| 43c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 44c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * The nodes on the prio_list list are sorted by priority to simplify 45c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * the insertion of new nodes. There are no nodes with duplicate 46c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * priorites on the list. 47c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 48c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * The nodes on the node_list is ordered by priority and can contain 49c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * entries which have the same priority. Those entries are ordered 50c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * FIFO 51c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 52c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Addition means: look for the prio_list node in the prio_list 53c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * for the priority of the node and insert it before the node_list 54c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * entry of the next prio_list node. If it is the first node of 55c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * that priority, add it to the prio_list in the right position and 56c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * insert it into the serialized node_list list 57c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 58c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Removal means remove it from the node_list and remove it from 59c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * the prio_list if the node_list list_head is non empty. In case 60c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * of removal from the prio_list it must be checked whether other 61c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * entries of the same priority are on the list or not. If there 62c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * is another entry of the same priority then this entry has to 63c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * replace the removed entry on the prio_list. If the entry which 64c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * is removed is the only entry of this priority then a simple 65c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * remove from both list is sufficient. 66c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 67c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * INT_MIN is the highest priority, 0 is the medium highest, INT_MAX 68c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * is lowest priority. 69c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 70c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * No locking is done, up to the caller. 71c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 72c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 73c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#ifndef _LINUX_PLIST_H_ 74c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#define _LINUX_PLIST_H_ 75c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 76c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#include <linux/kernel.h> 77c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#include <linux/list.h> 78c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#include <linux/spinlock_types.h> 79c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 80c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Querustruct plist_head { 81c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru struct list_head prio_list; 82c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru struct list_head node_list; 83c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#ifdef CONFIG_DEBUG_PI_LIST 84c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru spinlock_t *lock; 85c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#endif 86c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru}; 87c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 88c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Querustruct plist_node { 89c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru int prio; 90c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru struct plist_head plist; 91c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru}; 92c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 93c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#ifdef CONFIG_DEBUG_PI_LIST 94c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru# define PLIST_HEAD_LOCK_INIT(_lock) .lock = _lock 95c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#else 96c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru# define PLIST_HEAD_LOCK_INIT(_lock) 97c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#endif 98c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 99c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 100c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * #PLIST_HEAD_INIT - static struct plist_head initializer 101c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 102c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: struct plist_head variable name 103c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 104c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#define PLIST_HEAD_INIT(head, _lock) \ 105c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru{ \ 106c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru .prio_list = LIST_HEAD_INIT((head).prio_list), \ 107c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru .node_list = LIST_HEAD_INIT((head).node_list), \ 108c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru PLIST_HEAD_LOCK_INIT(&(_lock)) \ 109c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru} 110c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 111c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 112c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * #PLIST_NODE_INIT - static struct plist_node initializer 113c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 114c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @node: struct plist_node variable name 115c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @__prio: initial node priority 116c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 117c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#define PLIST_NODE_INIT(node, __prio) \ 118c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru{ \ 119c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru .prio = (__prio), \ 120c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru .plist = PLIST_HEAD_INIT((node).plist, NULL), \ 121c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru} 122c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 123c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 124c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_head_init - dynamic struct plist_head initializer 125c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 126c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: &struct plist_head pointer 127c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 128c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Querustatic inline void 129c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queruplist_head_init(struct plist_head *head, spinlock_t *lock) 130c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru{ 131c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru INIT_LIST_HEAD(&head->prio_list); 132c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru INIT_LIST_HEAD(&head->node_list); 133c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#ifdef CONFIG_DEBUG_PI_LIST 134c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru head->lock = lock; 135c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#endif 136c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru} 137c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 138c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 139c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_node_init - Dynamic struct plist_node initializer 140c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 141c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @node: &struct plist_node pointer 142c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @prio: initial node priority 143c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 144c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Querustatic inline void plist_node_init(struct plist_node *node, int prio) 145c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru{ 146c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru node->prio = prio; 147c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru plist_head_init(&node->plist, NULL); 148c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru} 149c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 150c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queruextern void plist_add(struct plist_node *node, struct plist_head *head); 151c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queruextern void plist_del(struct plist_node *node, struct plist_head *head); 152c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 153c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 154c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_for_each - iterate over the plist 155c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 156c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @pos1: the type * to use as a loop counter. 157c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: the head for your list. 158c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 159c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#define plist_for_each(pos, head) \ 160c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru list_for_each_entry(pos, &(head)->node_list, plist.node_list) 161c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 162c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 163c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_for_each_entry_safe - iterate over a plist of given type safe 164c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * against removal of list entry 165c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 166c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @pos1: the type * to use as a loop counter. 167c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @n1: another type * to use as temporary storage 168c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: the head for your list. 169c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 170c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#define plist_for_each_safe(pos, n, head) \ 171c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru list_for_each_entry_safe(pos, n, &(head)->node_list, plist.node_list) 172c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 173c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 174c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_for_each_entry - iterate over list of given type 175c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 176c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @pos: the type * to use as a loop counter. 177c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: the head for your list. 178c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @member: the name of the list_struct within the struct. 179c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 180c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#define plist_for_each_entry(pos, head, mem) \ 181c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru list_for_each_entry(pos, &(head)->node_list, mem.plist.node_list) 182c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 183c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 184c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_for_each_entry_safe - iterate over list of given type safe against 185c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * removal of list entry 186c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 187c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @pos: the type * to use as a loop counter. 188c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @n: another type * to use as temporary storage 189c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: the head for your list. 190c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @m: the name of the list_struct within the struct. 191c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 192c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#define plist_for_each_entry_safe(pos, n, head, m) \ 193c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru list_for_each_entry_safe(pos, n, &(head)->node_list, m.plist.node_list) 194c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 195c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 196c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_head_empty - return !0 if a plist_head is empty 197c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 198c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: &struct plist_head pointer 199c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 200c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Querustatic inline int plist_head_empty(const struct plist_head *head) 201c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru{ 202c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru return list_empty(&head->node_list); 203c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru} 204c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 205c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 206c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_node_empty - return !0 if plist_node is not on a list 207c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 208c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @node: &struct plist_node pointer 209c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 210c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Querustatic inline int plist_node_empty(const struct plist_node *node) 211c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru{ 212c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru return plist_head_empty(&node->plist); 213c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru} 214c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 215c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/* All functions below assume the plist_head is not empty. */ 216c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 217c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 218c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_first_entry - get the struct for the first entry 219c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 220c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @ptr: the &struct plist_head pointer. 221c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @type: the type of the struct this is embedded in. 222c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @member: the name of the list_struct within the struct. 223c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 224c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#ifdef CONFIG_DEBUG_PI_LIST 225c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru# define plist_first_entry(head, type, member) \ 226c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru({ \ 227c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru WARN_ON(plist_head_empty(head)); \ 228c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru container_of(plist_first(head), type, member); \ 229c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru}) 230c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#else 231c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru# define plist_first_entry(head, type, member) \ 232c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru container_of(plist_first(head), type, member) 233c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#endif 234c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 235c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru/** 236c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * plist_first - return the first node (and thus, highest priority) 237c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 238c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * @head: the &struct plist_head pointer 239c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * 240c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru * Assumes the plist is _not_ empty. 241c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru */ 242c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Querustatic inline struct plist_node* plist_first(const struct plist_head *head) 243c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru{ 244c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru return list_entry(head->node_list.next, 245c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru struct plist_node, plist.node_list); 246c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru} 247c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru 248c559cd81139f97cecad1ad91a0b2e25a5936d53Jean-Baptiste Queru#endif 249