Commit 773ff60e authored by Akinobu Mita's avatar Akinobu Mita Committed by Pekka Enberg
Browse files

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: default avatarAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: default avatarPekka Enberg <penberg@cs.helsinki.fi>
parent 3c92ec8a

include/linux/fault-inject.h

+9 −0
Original line number Diff line number Diff line
@@ -81,4 +81,13 @@ 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);

#else

static inline bool should_failslab(size_t size, gfp_t gfpflags)

{

	return false;

}

#endif /* CONFIG_FAILSLAB */



#endif /* _LINUX_FAULT_INJECT_H */

lib/Kconfig.debug

+1 −0
Original line number Diff line number Diff line
@@ -699,6 +699,7 @@ config FAULT_INJECTION 
config FAILSLAB

	bool "Fault-injection capability for kmalloc"

	depends on FAULT_INJECTION

	depends on SLAB || SLUB

	help

	  Provide fault-injection capability for kmalloc.

mm/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ obj-$(CONFIG_SLOB) += slob.o 
obj-$(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

mm/failslab.c

0 → 100644
+59 −0
Original line number Diff line number Diff line 
#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 */

mm/slab.c

+5 −70
Original line number Diff line number Diff line
@@ -3106,79 +3106,14 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, 
#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 should_fail(&failslab.attr, obj_size(cachep));

}



#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;

		return false;



	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;

	return should_failslab(obj_size(cachep), flags);

}



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 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, 
	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 @@ __cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller) 
	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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE