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authorFelix Blyakher <felixb@sgi.com>2009-06-10 17:07:47 -0500
committerFelix Blyakher <felixb@sgi.com>2009-06-10 17:07:47 -0500
commit4e73e0eb633f8a1b5cbf20e7f42c6dbfec1d1ca7 (patch)
tree0cea46e43f0625244c3d06a71d6559e5ec5419ca /include/linux/page-debug-flags.h
parent4156e735d3abde8e9243b5d22f7999dd3fffab2e (diff)
parent07a2039b8eb0af4ff464efd3dfd95de5c02648c6 (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Diffstat (limited to 'include/linux/page-debug-flags.h')
-rw-r--r--include/linux/page-debug-flags.h30
1 files changed, 30 insertions, 0 deletions
diff --git a/include/linux/page-debug-flags.h b/include/linux/page-debug-flags.h
new file mode 100644
index 000000000000..b0638fd91e92
--- /dev/null
+++ b/include/linux/page-debug-flags.h
@@ -0,0 +1,30 @@
+#ifndef LINUX_PAGE_DEBUG_FLAGS_H
+#define LINUX_PAGE_DEBUG_FLAGS_H
+
+/*
+ * page->debug_flags bits:
+ *
+ * PAGE_DEBUG_FLAG_POISON is set for poisoned pages. This is used to
+ * implement generic debug pagealloc feature. The pages are filled with
+ * poison patterns and set this flag after free_pages(). The poisoned
+ * pages are verified whether the patterns are not corrupted and clear
+ * the flag before alloc_pages().
+ */
+
+enum page_debug_flags {
+ PAGE_DEBUG_FLAG_POISON, /* Page is poisoned */
+};
+
+/*
+ * Ensure that CONFIG_WANT_PAGE_DEBUG_FLAGS reliably
+ * gets turned off when no debug features are enabling it!
+ */
+
+#ifdef CONFIG_WANT_PAGE_DEBUG_FLAGS
+#if !defined(CONFIG_PAGE_POISONING) \
+/* && !defined(CONFIG_PAGE_DEBUG_SOMETHING_ELSE) && ... */
+#error WANT_PAGE_DEBUG_FLAGS is turned on with no debug features!
+#endif
+#endif /* CONFIG_WANT_PAGE_DEBUG_FLAGS */
+
+#endif /* LINUX_PAGE_DEBUG_FLAGS_H */