summaryrefslogtreecommitdiff
path: root/include/linux/page-debug-flags.h
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2009-04-21 10:46:39 +0200
committerIngo Molnar <mingo@elte.hu>2009-04-21 10:46:54 +0200
commit8ecee4620e76aae418bfa0e8cc830e92cb559bbb (patch)
tree49a36784c0a26c8494a37087e37502101013b35d /include/linux/page-debug-flags.h
parent6424fb38667fffbbb1b90be0ffd9a0c540db6a4b (diff)
parenta939b96cccdb65df80a52447ec8e4a6d79c56dbb (diff)
Merge branch 'linus' into x86/mm
Merge reason: refresh the topic: there's been 290 non-merges commits upstream to arch/x86 alone. Signed-off-by: Ingo Molnar <mingo@elte.hu>
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 */