From: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Date: Fri, 21 Sep 2012 00:57:26 +0000 (+1000)
Subject: thp: remove some code depend on CONFIG_NUMA
X-Git-Tag: next-20120921~6^2~296
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=c97c1caa8fc3a16acc9e5983b101ff6f5aba17ed;p=karo-tx-linux.git

thp: remove some code depend on CONFIG_NUMA

If NUMA is disabled, hpage is used as page pre-alloc, so there are two
cases for hpage:

- it is !NULL, means the page is not consumed otherwise,
- the page has been consumed

If NUMA is enabled, hpage is just used as alloc-fail indicator which is
not a real page, NULL means not fail triggered.

So, we can release the page only if !IS_ERR_OR_NULL

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 5699bc040a40..e5ceb6f55fc7 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2307,11 +2307,8 @@ static void khugepaged_wait_work(void)
 
 static void khugepaged_loop(void)
 {
-	struct page *hpage;
+	struct page *hpage = NULL;
 
-#ifdef CONFIG_NUMA
-	hpage = NULL;
-#endif
 	while (likely(khugepaged_enabled())) {
 #ifndef CONFIG_NUMA
 		hpage = khugepaged_alloc_hugepage();
@@ -2325,10 +2322,9 @@ static void khugepaged_loop(void)
 #endif
 
 		khugepaged_do_scan(&hpage);
-#ifndef CONFIG_NUMA
-		if (hpage)
+
+		if (!IS_ERR_OR_NULL(hpage))
 			put_page(hpage);
-#endif
 
 		khugepaged_wait_work();
 	}