diff options
| -rw-r--r-- | Documentation/vm/slub.txt | 1 | ||||
| -rw-r--r-- | include/linux/fault-inject.h | 5 | ||||
| -rw-r--r-- | include/linux/slab.h | 5 | ||||
| -rw-r--r-- | mm/failslab.c | 18 | ||||
| -rw-r--r-- | mm/slab.c | 2 | ||||
| -rw-r--r-- | mm/slub.c | 29 |
6 files changed, 52 insertions, 8 deletions
diff --git a/Documentation/vm/slub.txt b/Documentation/vm/slub.txt index b37300edf27c..07375e73981a 100644 --- a/Documentation/vm/slub.txt +++ b/Documentation/vm/slub.txt @@ -41,6 +41,7 @@ Possible debug options are P Poisoning (object and padding) U User tracking (free and alloc) T Trace (please only use on single slabs) + A Toggle failslab filter mark for the cache O Switch debugging off for caches that would have caused higher minimum slab orders - Switch all debugging off (useful if the kernel is diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h index 06ca9b21dad2..7b64ad40e4ce 100644 --- a/include/linux/fault-inject.h +++ b/include/linux/fault-inject.h @@ -82,9 +82,10 @@ static inline void cleanup_fault_attr_dentries(struct fault_attr *attr) #endif /* CONFIG_FAULT_INJECTION */ #ifdef CONFIG_FAILSLAB -extern bool should_failslab(size_t size, gfp_t gfpflags); +extern bool should_failslab(size_t size, gfp_t gfpflags, unsigned long flags); #else -static inline bool should_failslab(size_t size, gfp_t gfpflags) +static inline bool should_failslab(size_t size, gfp_t gfpflags, + unsigned long flags) { return false; } diff --git a/include/linux/slab.h b/include/linux/slab.h index 2da8372519f5..488446289cab 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -70,6 +70,11 @@ #else # define SLAB_NOTRACK 0x00000000UL #endif +#ifdef CONFIG_FAILSLAB +# define SLAB_FAILSLAB 0x02000000UL /* Fault injection mark */ +#else +# define SLAB_FAILSLAB 0x00000000UL +#endif /* The following flags affect the page allocator grouping pages by mobility */ #define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */ 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 <linux/fault-inject.h> #include <linux/gfp.h> +#include <linux/slab.h> 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); } diff --git a/mm/slab.c b/mm/slab.c index 7451bdacaf18..33496b704859 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3101,7 +3101,7 @@ static bool slab_should_failslab(struct kmem_cache *cachep, gfp_t flags) if (cachep == &cache_cache) return false; - return should_failslab(obj_size(cachep), flags); + return should_failslab(obj_size(cachep), flags, cachep->flags); } static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) diff --git a/mm/slub.c b/mm/slub.c index 8d71aaf888d7..cab5288736c8 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -151,7 +151,8 @@ * Set of flags that will prevent slab merging */ #define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ - SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE) + SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \ + SLAB_FAILSLAB) #define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \ SLAB_CACHE_DMA | SLAB_NOTRACK) @@ -1020,6 +1021,9 @@ static int __init setup_slub_debug(char *str) case 't': slub_debug |= SLAB_TRACE; break; + case 'a': + slub_debug |= SLAB_FAILSLAB; + break; default: printk(KERN_ERR "slub_debug option '%c' " "unknown. skipped\n", *str); @@ -1718,7 +1722,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s, lockdep_trace_alloc(gfpflags); might_sleep_if(gfpflags & __GFP_WAIT); - if (should_failslab(s->objsize, gfpflags)) + if (should_failslab(s->objsize, gfpflags, s->flags)) return NULL; local_irq_save(flags); @@ -4171,6 +4175,23 @@ static ssize_t trace_store(struct kmem_cache *s, const char *buf, } SLAB_ATTR(trace); +#ifdef CONFIG_FAILSLAB +static ssize_t failslab_show(struct kmem_cache *s, char *buf) +{ + return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB)); +} + +static ssize_t failslab_store(struct kmem_cache *s, const char *buf, + size_t length) +{ + s->flags &= ~SLAB_FAILSLAB; + if (buf[0] == '1') + s->flags |= SLAB_FAILSLAB; + return length; +} +SLAB_ATTR(failslab); +#endif + static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) { return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); @@ -4467,6 +4488,10 @@ static struct attribute *slab_attrs[] = { &deactivate_remote_frees_attr.attr, &order_fallback_attr.attr, #endif +#ifdef CONFIG_FAILSLAB + &failslab_attr.attr, +#endif + NULL }; |