From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752793Ab1IFGZU (ORCPT ); Tue, 6 Sep 2011 02:25:20 -0400 Received: from mga02.intel.com ([134.134.136.20]:60692 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752730Ab1IFGZP (ORCPT ); Tue, 6 Sep 2011 02:25:15 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,351,1309762800"; d="scan'208";a="45363864" From: Huang Ying To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Andi Kleen , ying.huang@intel.com, Mathieu Desnoyers , Peter Zijlstra Subject: [PATCH -mm 1/4] llist, Make all llist functions inline Date: Tue, 6 Sep 2011 14:25:04 +0800 Message-Id: <1315290307-25145-1-git-send-email-ying.huang@intel.com> X-Mailer: git-send-email 1.7.5.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Because llist may be used in performance critical code path, make all llist functions inline to avoid function calling overhead. Signed-off-by: Huang Ying Cc: Mathieu Desnoyers Cc: Peter Zijlstra --- drivers/acpi/apei/Kconfig | 1 include/linux/llist.h | 122 +++++++++++++++++++++++++++++++++++++++++-- lib/Kconfig | 3 - lib/Makefile | 2 lib/llist.c | 129 ---------------------------------------------- 5 files changed, 116 insertions(+), 141 deletions(-) delete mode 100644 lib/llist.c --- a/drivers/acpi/apei/Kconfig +++ b/drivers/acpi/apei/Kconfig @@ -14,7 +14,6 @@ config ACPI_APEI_GHES depends on ACPI_APEI && X86 select ACPI_HED select IRQ_WORK - select LLIST select GENERIC_ALLOCATOR help Generic Hardware Error Source provides a way to report --- a/include/linux/llist.h +++ b/include/linux/llist.h @@ -37,8 +37,28 @@ * architectures that don't have NMI-safe cmpxchg implementation, the * list can NOT be used in NMI handler. So code uses the list in NMI * handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. + * + * Copyright 2010,2011 Intel Corp. + * Author: Huang Ying + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 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. + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include +#include +#include + struct llist_head { struct llist_node *first; }; @@ -113,14 +133,104 @@ static inline void init_llist_head(struc * test whether the list is empty without deleting something from the * list. */ -static inline int llist_empty(const struct llist_head *head) +static inline bool llist_empty(const struct llist_head *head) { return ACCESS_ONCE(head->first) == NULL; } -void llist_add(struct llist_node *new, struct llist_head *head); -void llist_add_batch(struct llist_node *new_first, struct llist_node *new_last, - struct llist_head *head); -struct llist_node *llist_del_first(struct llist_head *head); -struct llist_node *llist_del_all(struct llist_head *head); +/** + * llist_add - add a new entry + * @new: new entry to be added + * @head: the head for your lock-less list + */ +static inline void llist_add(struct llist_node *new, struct llist_head *head) +{ + struct llist_node *entry, *old_entry; + +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + entry = head->first; + do { + old_entry = entry; + new->next = entry; + cpu_relax(); + } while ((entry = cmpxchg(&head->first, old_entry, new)) != old_entry); +} + +/** + * llist_add_batch - add several linked entries in batch + * @new_first: first entry in batch to be added + * @new_last: last entry in batch to be added + * @head: the head for your lock-less list + */ +static inline void llist_add_batch(struct llist_node *new_first, + struct llist_node *new_last, + struct llist_head *head) +{ + struct llist_node *entry, *old_entry; + +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + entry = head->first; + do { + old_entry = entry; + new_last->next = entry; + cpu_relax(); + } while ((entry = cmpxchg(&head->first, old_entry, new_first)) != old_entry); +} + +/** + * llist_del_first - delete the first entry of lock-less list + * @head: the head for your lock-less list + * + * If list is empty, return NULL, otherwise, return the first entry + * deleted, this is the newest added one. + * + * Only one llist_del_first user can be used simultaneously with + * multiple llist_add users without lock. Because otherwise + * llist_del_first, llist_add, llist_add (or llist_del_all, llist_add, + * llist_add) sequence in another user may change @head->first->next, + * but keep @head->first. If multiple consumers are needed, please + * use llist_del_all or use lock between consumers. + */ +static inline struct llist_node *llist_del_first(struct llist_head *head) +{ + struct llist_node *entry, *old_entry, *next; + +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + entry = head->first; + do { + if (entry == NULL) + return NULL; + old_entry = entry; + next = entry->next; + cpu_relax(); + } while ((entry = cmpxchg(&head->first, old_entry, next)) != old_entry); + + return entry; +} + +/** + * llist_del_all - delete all entries from lock-less list + * @head: the head of lock-less list to delete all entries + * + * If list is empty, return NULL, otherwise, delete all entries and + * return the pointer to the first entry. The order of entries + * deleted is from the newest to the oldest added one. + */ +static inline struct llist_node *llist_del_all(struct llist_head *head) +{ +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + return xchg(&head->first, NULL); +} #endif /* LLIST_H */ --- a/lib/Kconfig +++ b/lib/Kconfig @@ -276,7 +276,4 @@ config CORDIC so its calculations are in fixed point. Modules can select this when they require this function. Module will be called cordic. -config LLIST - bool - endmenu --- a/lib/Makefile +++ b/lib/Makefile @@ -116,8 +116,6 @@ obj-$(CONFIG_CPU_RMAP) += cpu_rmap.o obj-$(CONFIG_CORDIC) += cordic.o -obj-$(CONFIG_LLIST) += llist.o - hostprogs-y := gen_crc32table clean-files := crc32table.h --- a/lib/llist.c +++ /dev/null @@ -1,129 +0,0 @@ -/* - * Lock-less NULL terminated single linked list - * - * The basic atomic operation of this list is cmpxchg on long. On - * architectures that don't have NMI-safe cmpxchg implementation, the - * list can NOT be used in NMI handler. So code uses the list in NMI - * handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. - * - * Copyright 2010,2011 Intel Corp. - * Author: Huang Ying - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License version - * 2 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. - * - * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ -#include -#include -#include -#include - -#include - -/** - * llist_add - add a new entry - * @new: new entry to be added - * @head: the head for your lock-less list - */ -void llist_add(struct llist_node *new, struct llist_head *head) -{ - struct llist_node *entry, *old_entry; - -#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG - BUG_ON(in_nmi()); -#endif - - entry = head->first; - do { - old_entry = entry; - new->next = entry; - cpu_relax(); - } while ((entry = cmpxchg(&head->first, old_entry, new)) != old_entry); -} -EXPORT_SYMBOL_GPL(llist_add); - -/** - * llist_add_batch - add several linked entries in batch - * @new_first: first entry in batch to be added - * @new_last: last entry in batch to be added - * @head: the head for your lock-less list - */ -void llist_add_batch(struct llist_node *new_first, struct llist_node *new_last, - struct llist_head *head) -{ - struct llist_node *entry, *old_entry; - -#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG - BUG_ON(in_nmi()); -#endif - - entry = head->first; - do { - old_entry = entry; - new_last->next = entry; - cpu_relax(); - } while ((entry = cmpxchg(&head->first, old_entry, new_first)) != old_entry); -} -EXPORT_SYMBOL_GPL(llist_add_batch); - -/** - * llist_del_first - delete the first entry of lock-less list - * @head: the head for your lock-less list - * - * If list is empty, return NULL, otherwise, return the first entry - * deleted, this is the newest added one. - * - * Only one llist_del_first user can be used simultaneously with - * multiple llist_add users without lock. Because otherwise - * llist_del_first, llist_add, llist_add (or llist_del_all, llist_add, - * llist_add) sequence in another user may change @head->first->next, - * but keep @head->first. If multiple consumers are needed, please - * use llist_del_all or use lock between consumers. - */ -struct llist_node *llist_del_first(struct llist_head *head) -{ - struct llist_node *entry, *old_entry, *next; - -#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG - BUG_ON(in_nmi()); -#endif - - entry = head->first; - do { - if (entry == NULL) - return NULL; - old_entry = entry; - next = entry->next; - cpu_relax(); - } while ((entry = cmpxchg(&head->first, old_entry, next)) != old_entry); - - return entry; -} -EXPORT_SYMBOL_GPL(llist_del_first); - -/** - * llist_del_all - delete all entries from lock-less list - * @head: the head of lock-less list to delete all entries - * - * If list is empty, return NULL, otherwise, delete all entries and - * return the pointer to the first entry. The order of entries - * deleted is from the newest to the oldest added one. - */ -struct llist_node *llist_del_all(struct llist_head *head) -{ -#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG - BUG_ON(in_nmi()); -#endif - - return xchg(&head->first, NULL); -} -EXPORT_SYMBOL_GPL(llist_del_all);