From c54ad30c784b84d0275152d0ca80985b21471811 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 6 Jan 2006 00:10:56 -0800 Subject: [PATCH] mm: pagealloc opt Slightly optimise some page allocation and freeing functions by taking advantage of knowing whether or not interrupts are disabled. Signed-off-by: Nick Piggin Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'mm') diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 07825c637a5..680cbe5b6ba 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -375,11 +375,10 @@ static int free_pages_bulk(struct zone *zone, int count, struct list_head *list, unsigned int order) { - unsigned long flags; struct page *page = NULL; int ret = 0; - spin_lock_irqsave(&zone->lock, flags); + spin_lock(&zone->lock); zone->all_unreclaimable = 0; zone->pages_scanned = 0; while (!list_empty(list) && count--) { @@ -389,12 +388,13 @@ free_pages_bulk(struct zone *zone, int count, __free_pages_bulk(page, zone, order); ret++; } - spin_unlock_irqrestore(&zone->lock, flags); + spin_unlock(&zone->lock); return ret; } void __free_pages_ok(struct page *page, unsigned int order) { + unsigned long flags; LIST_HEAD(list); int i; int reserved = 0; @@ -415,7 +415,9 @@ void __free_pages_ok(struct page *page, unsigned int order) list_add(&page->lru, &list); mod_page_state(pgfree, 1 << order); kernel_map_pages(page, 1<lock, flags); + spin_lock(&zone->lock); for (i = 0; i < count; ++i) { page = __rmqueue(zone, order); if (page == NULL) @@ -552,7 +553,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, allocated++; list_add_tail(&page->lru, list); } - spin_unlock_irqrestore(&zone->lock, flags); + spin_unlock(&zone->lock); return allocated; } @@ -589,6 +590,7 @@ void drain_remote_pages(void) #if defined(CONFIG_PM) || defined(CONFIG_HOTPLUG_CPU) static void __drain_pages(unsigned int cpu) { + unsigned long flags; struct zone *zone; int i; @@ -600,8 +602,10 @@ static void __drain_pages(unsigned int cpu) struct per_cpu_pages *pcp; pcp = &pset->pcp[i]; + local_irq_save(flags); pcp->count -= free_pages_bulk(zone, pcp->count, &pcp->list, 0); + local_irq_restore(flags); } } } @@ -744,7 +748,7 @@ again: if (pcp->count <= pcp->low) pcp->count += rmqueue_bulk(zone, 0, pcp->batch, &pcp->list); - if (pcp->count) { + if (likely(pcp->count)) { page = list_entry(pcp->list.next, struct page, lru); list_del(&page->lru); pcp->count--; -- cgit v1.2.3