From cc33a303f1c155cf0147964586bb80fa732d8a21 Mon Sep 17 00:00:00 2001 From: Joonsoo Kim Date: Tue, 11 Dec 2012 16:01:20 -0800 Subject: [PATCH] mm, highmem: remove useless pool_lock The pool_lock protects the page_address_pool from concurrent access. But, access to the page_address_pool is already protected by kmap_lock. So remove it. Signed-off-by: Joonsoo Kim Cc: Mel Gorman Reviewed-by: Minchan Kin Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/highmem.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/mm/highmem.c b/mm/highmem.c index 2576a7118981..f0f0f1d5e691 100644 --- a/mm/highmem.c +++ b/mm/highmem.c @@ -328,7 +328,6 @@ struct page_address_map { * page_address_map freelist, allocated from page_address_maps. */ static struct list_head page_address_pool; /* freelist */ -static spinlock_t pool_lock; /* protects page_address_pool */ /* * Hash table bucket @@ -395,11 +394,9 @@ void set_page_address(struct page *page, void *virtual) if (virtual) { /* Add */ BUG_ON(list_empty(&page_address_pool)); - spin_lock_irqsave(&pool_lock, flags); pam = list_entry(page_address_pool.next, struct page_address_map, list); list_del(&pam->list); - spin_unlock_irqrestore(&pool_lock, flags); pam->page = page; pam->virtual = virtual; @@ -413,9 +410,7 @@ void set_page_address(struct page *page, void *virtual) if (pam->page == page) { list_del(&pam->list); spin_unlock_irqrestore(&pas->lock, flags); - spin_lock_irqsave(&pool_lock, flags); list_add_tail(&pam->list, &page_address_pool); - spin_unlock_irqrestore(&pool_lock, flags); goto done; } } @@ -438,7 +433,6 @@ void __init page_address_init(void) INIT_LIST_HEAD(&page_address_htable[i].lh); spin_lock_init(&page_address_htable[i].lock); } - spin_lock_init(&pool_lock); } #endif /* defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) */ -- 2.20.1