[PATCH] fault-injection capability for alloc_pages()

This patch provides fault-injection capability for alloc_pages()

Boot option:

fail_page_alloc=<interval>,<probability>,<space>,<times>

	<interval> -- specifies the interval of failures.

	<probability> -- specifies how often it should fail in percent.

	<space> -- specifies the size of free space where memory can be
		   allocated safely in pages.

	<times> -- specifies how many times failures may happen at most.

Debugfs:

/debug/fail_page_alloc/interval
/debug/fail_page_alloc/probability
/debug/fail_page_alloc/specifies
/debug/fail_page_alloc/times
/debug/fail_page_alloc/ignore-gfp-highmem
/debug/fail_page_alloc/ignore-gfp-wait

Example:

	fail_page_alloc=10,100,0,-1

The page allocation (alloc_pages(), ...) fails once per 10 times.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c7f567a57d7d..c66b7b400c9f 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -424,6 +424,13 @@ config FAILSLAB
         help
           This option provides fault-injection capabilitiy for kmalloc.
 
+config FAIL_PAGE_ALLOC
+        bool "Fault-injection capabilitiy for alloc_pages()"
+        depends on DEBUG_KERNEL
+        select FAULT_INJECTION
+        help
+          This option provides fault-injection capabilitiy for alloc_pages().
+
 config FAULT_INJECTION_DEBUG_FS
         bool "Debugfs entries for fault-injection capabilities"
         depends on FAULT_INJECTION && SYSFS