Skip to content

Commit

Permalink
mm: fault-inject take over bootstrap kmem_cache check
Browse files Browse the repository at this point in the history
Remove the SLAB specific function slab_should_failslab(), by moving the
check against fault-injection for the bootstrap slab, into the shared
function should_failslab() (used by both SLAB and SLUB).

This is a step towards sharing alloc_hook's between SLUB and SLAB.

This bootstrap slab "kmem_cache" is used for allocating struct
kmem_cache objects to the allocator itself.

Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
  • Loading branch information
netoptimizer authored and torvalds committed Mar 15, 2016
1 parent 11c7aec commit fab9963
Show file tree
Hide file tree
Showing 4 changed files with 14 additions and 17 deletions.
5 changes: 2 additions & 3 deletions include/linux/fault-inject.h
Original file line number Diff line number Diff line change
Expand Up @@ -62,10 +62,9 @@ static inline struct dentry *fault_create_debugfs_attr(const char *name,
#endif /* CONFIG_FAULT_INJECTION */

#ifdef CONFIG_FAILSLAB
extern bool should_failslab(size_t size, gfp_t gfpflags, unsigned long flags);
extern bool should_failslab(struct kmem_cache *s, gfp_t gfpflags);
#else
static inline bool should_failslab(size_t size, gfp_t gfpflags,
unsigned long flags)
static inline bool should_failslab(struct kmem_cache *s, gfp_t gfpflags)
{
return false;
}
Expand Down
12 changes: 9 additions & 3 deletions mm/failslab.c
Original file line number Diff line number Diff line change
@@ -1,5 +1,7 @@
#include <linux/fault-inject.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include "slab.h"

static struct {
struct fault_attr attr;
Expand All @@ -11,18 +13,22 @@ static struct {
.cache_filter = false,
};

bool should_failslab(size_t size, gfp_t gfpflags, unsigned long cache_flags)
bool should_failslab(struct kmem_cache *s, gfp_t gfpflags)
{
/* No fault-injection for bootstrap cache */
if (unlikely(s == kmem_cache))
return false;

if (gfpflags & __GFP_NOFAIL)
return false;

if (failslab.ignore_gfp_reclaim && (gfpflags & __GFP_RECLAIM))
return false;

if (failslab.cache_filter && !(cache_flags & SLAB_FAILSLAB))
if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
return false;

return should_fail(&failslab.attr, size);
return should_fail(&failslab.attr, s->object_size);
}

static int __init setup_failslab(char *str)
Expand Down
12 changes: 2 additions & 10 deletions mm/slab.c
Original file line number Diff line number Diff line change
Expand Up @@ -2926,14 +2926,6 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
#define cache_alloc_debugcheck_after(a,b,objp,d) (objp)
#endif

static bool slab_should_failslab(struct kmem_cache *cachep, gfp_t flags)
{
if (unlikely(cachep == kmem_cache))
return false;

return should_failslab(cachep->object_size, flags, cachep->flags);
}

static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags)
{
void *objp;
Expand Down Expand Up @@ -3155,7 +3147,7 @@ slab_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid,

lockdep_trace_alloc(flags);

if (slab_should_failslab(cachep, flags))
if (should_failslab(cachep, flags))
return NULL;

cachep = memcg_kmem_get_cache(cachep, flags);
Expand Down Expand Up @@ -3243,7 +3235,7 @@ slab_alloc(struct kmem_cache *cachep, gfp_t flags, unsigned long caller)

lockdep_trace_alloc(flags);

if (slab_should_failslab(cachep, flags))
if (should_failslab(cachep, flags))
return NULL;

cachep = memcg_kmem_get_cache(cachep, flags);
Expand Down
2 changes: 1 addition & 1 deletion mm/slab.h
Original file line number Diff line number Diff line change
Expand Up @@ -360,7 +360,7 @@ static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
lockdep_trace_alloc(flags);
might_sleep_if(gfpflags_allow_blocking(flags));

if (should_failslab(s->object_size, flags, s->flags))
if (should_failslab(s, flags))
return NULL;

return memcg_kmem_get_cache(s, flags);
Expand Down

0 comments on commit fab9963

Please sign in to comment.