From 1230db8e1543c0471dd165727d34647ab098cc1e Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Thu, 8 Sep 2011 14:00:42 +0800 Subject: [PATCH] llist: Make some llist functions inline Because llist code will be used in performance critical scheduler code path, make llist_add() and llist_del_all() inline to avoid function calling overhead and related 'glue' overhead. Signed-off-by: Huang Ying Acked-by: Mathieu Desnoyers Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1315461646-1379-2-git-send-email-ying.huang@intel.com Signed-off-by: Ingo Molnar --- drivers/acpi/apei/Kconfig | 1 - include/linux/llist.h | 64 +++++++++++++++++++++++++++++++++++---- lib/Kconfig | 3 -- lib/Makefile | 4 +-- lib/llist.c | 40 ------------------------ 5 files changed, 59 insertions(+), 53 deletions(-) diff --git a/drivers/acpi/apei/Kconfig b/drivers/acpi/apei/Kconfig index e3f47872ec2..f0c1ce95a0e 100644 --- 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 diff --git a/include/linux/llist.h b/include/linux/llist.h index aa0c8b5b3cd..3eccdfd6609 100644 --- 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 +133,46 @@ static inline void init_llist_head(struct llist_head *list) * 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_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 */ diff --git a/lib/Kconfig b/lib/Kconfig index 6c695ff9cab..32f3e5ae2be 100644 --- 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 diff --git a/lib/Makefile b/lib/Makefile index 3f5bc6d903e..a4da283f5dc 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -22,7 +22,7 @@ lib-y += kobject.o kref.o klist.o obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ string_helpers.o gcd.o lcm.o list_sort.o uuid.o flex_array.o \ - bsearch.o find_last_bit.o find_next_bit.o + bsearch.o find_last_bit.o find_next_bit.o llist.o obj-y += kstrtox.o obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o @@ -115,8 +115,6 @@ obj-$(CONFIG_CPU_RMAP) += cpu_rmap.o obj-$(CONFIG_CORDIC) += cordic.o -obj-$(CONFIG_LLIST) += llist.o - hostprogs-y := gen_crc32table clean-files := crc32table.h diff --git a/lib/llist.c b/lib/llist.c index da445724fa1..3e3fa9139c4 100644 --- a/lib/llist.c +++ b/lib/llist.c @@ -29,28 +29,6 @@ #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 @@ -109,21 +87,3 @@ struct llist_node *llist_del_first(struct llist_head *head) 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); -- 2.20.1