From: Chen, Kenneth W <kenneth.w.chen@intel.com>
Date: Thu, 7 Dec 2006 04:31:39 +0000 (-0800)
Subject: [PATCH] __unmap_hugepage_range(): add comment
X-Git-Tag: v2.6.20-rc1~145^2^2~357
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c0a499c2c42992cff097b38be29d2ba60d2fd99a;p=linux-2.6

[PATCH] __unmap_hugepage_range(): add comment

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index a088f593a8..f7355bf2f2 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -365,6 +365,11 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
 	pte_t pte;
 	struct page *page;
 	struct page *tmp;
+	/*
+	 * A page gathering list, protected by per file i_mmap_lock. The
+	 * lock is used to avoid list corruption from multiple unmapping
+	 * of the same page since we are using page->lru.
+	 */
 	LIST_HEAD(page_list);
 
 	WARN_ON(!is_vm_hugetlb_page(vma));