SLUB: failslab support
Currently fault-injection capability for SLAB allocator is only
available to SLAB. This patch makes it available to SLUB, too.
[penberg@cs.helsinki.fi: unify slab and slub implementations]
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h
index 32368c4..06ca9b2 100644
--- a/include/linux/fault-inject.h
+++ b/include/linux/fault-inject.h
@@ -81,4 +81,13 @@
#endif /* CONFIG_FAULT_INJECTION */
+#ifdef CONFIG_FAILSLAB
+extern bool should_failslab(size_t size, gfp_t gfpflags);
+#else
+static inline bool should_failslab(size_t size, gfp_t gfpflags)
+{
+ return false;
+}
+#endif /* CONFIG_FAILSLAB */
+
#endif /* _LINUX_FAULT_INJECT_H */
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index b0f239e..af65ae7 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -699,6 +699,7 @@
config FAILSLAB
bool "Fault-injection capability for kmalloc"
depends on FAULT_INJECTION
+ depends on SLAB || SLUB
help
Provide fault-injection capability for kmalloc.
diff --git a/mm/Makefile b/mm/Makefile
index c06b45a..51c2770 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -28,6 +28,7 @@
obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o
obj-$(CONFIG_SLAB) += slab.o
obj-$(CONFIG_SLUB) += slub.o
+obj-$(CONFIG_FAILSLAB) += failslab.o
obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
obj-$(CONFIG_FS_XIP) += filemap_xip.o
obj-$(CONFIG_MIGRATION) += migrate.o
diff --git a/mm/failslab.c b/mm/failslab.c
new file mode 100644
index 0000000..7c6ea64
--- /dev/null
+++ b/mm/failslab.c
@@ -0,0 +1,59 @@
+#include <linux/fault-inject.h>
+
+static struct {
+ struct fault_attr attr;
+ u32 ignore_gfp_wait;
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+ struct dentry *ignore_gfp_wait_file;
+#endif
+} failslab = {
+ .attr = FAULT_ATTR_INITIALIZER,
+ .ignore_gfp_wait = 1,
+};
+
+bool should_failslab(size_t size, gfp_t gfpflags)
+{
+ if (gfpflags & __GFP_NOFAIL)
+ return false;
+
+ if (failslab.ignore_gfp_wait && (gfpflags & __GFP_WAIT))
+ return false;
+
+ return should_fail(&failslab.attr, size);
+}
+
+static int __init setup_failslab(char *str)
+{
+ return setup_fault_attr(&failslab.attr, 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;
+ struct dentry *dir;
+ int err;
+
+ err = init_fault_attr_dentries(&failslab.attr, "failslab");
+ if (err)
+ return err;
+ dir = failslab.attr.dentries.dir;
+
+ failslab.ignore_gfp_wait_file =
+ debugfs_create_bool("ignore-gfp-wait", mode, dir,
+ &failslab.ignore_gfp_wait);
+
+ if (!failslab.ignore_gfp_wait_file) {
+ err = -ENOMEM;
+ debugfs_remove(failslab.ignore_gfp_wait_file);
+ cleanup_fault_attr_dentries(&failslab.attr);
+ }
+
+ return err;
+}
+
+late_initcall(failslab_debugfs_init);
+
+#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
diff --git a/mm/slab.c b/mm/slab.c
index 0918751..c347dd8 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3106,79 +3106,14 @@
#define cache_alloc_debugcheck_after(a,b,objp,d) (objp)
#endif
-#ifdef CONFIG_FAILSLAB
-
-static struct failslab_attr {
-
- struct fault_attr attr;
-
- u32 ignore_gfp_wait;
-#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
- struct dentry *ignore_gfp_wait_file;
-#endif
-
-} failslab = {
- .attr = FAULT_ATTR_INITIALIZER,
- .ignore_gfp_wait = 1,
-};
-
-static int __init setup_failslab(char *str)
-{
- return setup_fault_attr(&failslab.attr, str);
-}
-__setup("failslab=", setup_failslab);
-
-static int should_failslab(struct kmem_cache *cachep, gfp_t flags)
+static bool slab_should_failslab(struct kmem_cache *cachep, gfp_t flags)
{
if (cachep == &cache_cache)
- return 0;
- if (flags & __GFP_NOFAIL)
- return 0;
- if (failslab.ignore_gfp_wait && (flags & __GFP_WAIT))
- return 0;
+ return false;
- return should_fail(&failslab.attr, obj_size(cachep));
+ return should_failslab(obj_size(cachep), flags);
}
-#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
-
-static int __init failslab_debugfs(void)
-{
- mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
- struct dentry *dir;
- int err;
-
- err = init_fault_attr_dentries(&failslab.attr, "failslab");
- if (err)
- return err;
- dir = failslab.attr.dentries.dir;
-
- failslab.ignore_gfp_wait_file =
- debugfs_create_bool("ignore-gfp-wait", mode, dir,
- &failslab.ignore_gfp_wait);
-
- if (!failslab.ignore_gfp_wait_file) {
- err = -ENOMEM;
- debugfs_remove(failslab.ignore_gfp_wait_file);
- cleanup_fault_attr_dentries(&failslab.attr);
- }
-
- return err;
-}
-
-late_initcall(failslab_debugfs);
-
-#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
-
-#else /* CONFIG_FAILSLAB */
-
-static inline int should_failslab(struct kmem_cache *cachep, gfp_t flags)
-{
- return 0;
-}
-
-#endif /* CONFIG_FAILSLAB */
-
static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags)
{
void *objp;
@@ -3381,7 +3316,7 @@
unsigned long save_flags;
void *ptr;
- if (should_failslab(cachep, flags))
+ if (slab_should_failslab(cachep, flags))
return NULL;
cache_alloc_debugcheck_before(cachep, flags);
@@ -3457,7 +3392,7 @@
unsigned long save_flags;
void *objp;
- if (should_failslab(cachep, flags))
+ if (slab_should_failslab(cachep, flags))
return NULL;
cache_alloc_debugcheck_before(cachep, flags);
diff --git a/mm/slub.c b/mm/slub.c
index a2cd47d..640fde7 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -24,6 +24,7 @@
#include <linux/kallsyms.h>
#include <linux/memory.h>
#include <linux/math64.h>
+#include <linux/fault-inject.h>
/*
* Lock order:
@@ -1591,6 +1592,9 @@
unsigned long flags;
unsigned int objsize;
+ if (should_failslab(s->objsize, gfpflags))
+ return NULL;
+
local_irq_save(flags);
c = get_cpu_slab(s, smp_processor_id());
objsize = c->objsize;