From 4c13dd3b48fcb6fbe44f241eb11a057ecd1cba75 Mon Sep 17 00:00:00 2001 From: Dmitry Monakhov Date: Fri, 26 Feb 2010 09:36:12 +0300 Subject: failslab: add ability to filter slab caches This patch allow to inject faults only for specific slabs. In order to preserve default behavior cache filter is off by default (all caches are faulty). One may define specific set of slabs like this: # mark skbuff_head_cache as faulty echo 1 > /sys/kernel/slab/skbuff_head_cache/failslab # Turn on cache filter (off by default) echo 1 > /sys/kernel/debug/failslab/cache-filter # Turn on fault injection echo 1 > /sys/kernel/debug/failslab/times echo 1 > /sys/kernel/debug/failslab/probability Acked-by: David Rientjes Acked-by: Akinobu Mita Acked-by: Christoph Lameter Signed-off-by: Dmitry Monakhov Signed-off-by: Pekka Enberg --- mm/failslab.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'mm/failslab.c') diff --git a/mm/failslab.c b/mm/failslab.c index 9339de5f0a91..bb41f98dd8b7 100644 --- a/mm/failslab.c +++ b/mm/failslab.c @@ -1,18 +1,22 @@ #include #include +#include static struct { struct fault_attr attr; u32 ignore_gfp_wait; + int cache_filter; #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS struct dentry *ignore_gfp_wait_file; + struct dentry *cache_filter_file; #endif } failslab = { .attr = FAULT_ATTR_INITIALIZER, .ignore_gfp_wait = 1, + .cache_filter = 0, }; -bool should_failslab(size_t size, gfp_t gfpflags) +bool should_failslab(size_t size, gfp_t gfpflags, unsigned long cache_flags) { if (gfpflags & __GFP_NOFAIL) return false; @@ -20,6 +24,9 @@ bool should_failslab(size_t size, gfp_t gfpflags) if (failslab.ignore_gfp_wait && (gfpflags & __GFP_WAIT)) return false; + if (failslab.cache_filter && !(cache_flags & SLAB_FAILSLAB)) + return false; + return should_fail(&failslab.attr, size); } @@ -30,7 +37,6 @@ static int __init setup_failslab(char *str) __setup("failslab=", setup_failslab); #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS - static int __init failslab_debugfs_init(void) { mode_t mode = S_IFREG | S_IRUSR | S_IWUSR; @@ -46,8 +52,14 @@ static int __init failslab_debugfs_init(void) debugfs_create_bool("ignore-gfp-wait", mode, dir, &failslab.ignore_gfp_wait); - if (!failslab.ignore_gfp_wait_file) { + failslab.cache_filter_file = + debugfs_create_bool("cache-filter", mode, dir, + &failslab.cache_filter); + + if (!failslab.ignore_gfp_wait_file || + !failslab.cache_filter_file) { err = -ENOMEM; + debugfs_remove(failslab.cache_filter_file); debugfs_remove(failslab.ignore_gfp_wait_file); cleanup_fault_attr_dentries(&failslab.attr); } -- cgit v1.2.3