diff mbox series

[v4,22/36] mm/slab: add allocation accounting into slab allocation and free paths

Message ID 20240221194052.927623-23-surenb@google.com
State New
Headers
Series Memory allocation profiling |

Commit Message

Suren Baghdasaryan Feb. 21, 2024, 7:40 p.m. UTC 
  Account slab allocations using codetag reference embedded into slabobj_ext.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Co-developed-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
 mm/slab.h | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 mm/slub.c |  9 ++++++++
 2 files changed, 75 insertions(+)

Comments

Vlastimil Babka Feb. 27, 2024, 1:07 p.m. UTC | #1 
On 2/21/24 20:40, Suren Baghdasaryan wrote:
> Account slab allocations using codetag reference embedded into slabobj_ext.
> 
> Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> Co-developed-by: Kent Overstreet <kent.overstreet@linux.dev>
> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
> Reviewed-by: Kees Cook <keescook@chromium.org>
> ---
>  mm/slab.h | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  mm/slub.c |  9 ++++++++
>  2 files changed, 75 insertions(+)
> 
> diff --git a/mm/slab.h b/mm/slab.h
> index 13b6ba2abd74..c4bd0d5348cb 100644
> --- a/mm/slab.h
> +++ b/mm/slab.h
> @@ -567,6 +567,46 @@ static inline struct slabobj_ext *slab_obj_exts(struct slab *slab)
>  int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s,
>  			gfp_t gfp, bool new_slab);
>  
> +static inline bool need_slab_obj_ext(void)
> +{
> +#ifdef CONFIG_MEM_ALLOC_PROFILING
> +	if (mem_alloc_profiling_enabled())
> +		return true;
> +#endif
> +	/*
> +	 * CONFIG_MEMCG_KMEM creates vector of obj_cgroup objects conditionally
> +	 * inside memcg_slab_post_alloc_hook. No other users for now.
> +	 */
> +	return false;
> +}
> +
> +static inline struct slabobj_ext *
> +prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
> +{
> +	struct slab *slab;
> +
> +	if (!p)
> +		return NULL;
> +
> +	if (!need_slab_obj_ext())
> +		return NULL;
> +
> +	if (s->flags & SLAB_NO_OBJ_EXT)
> +		return NULL;
> +
> +	if (flags & __GFP_NO_OBJ_EXT)
> +		return NULL;
> +
> +	slab = virt_to_slab(p);
> +	if (!slab_obj_exts(slab) &&
> +	    WARN(alloc_slab_obj_exts(slab, s, flags, false),
> +		 "%s, %s: Failed to create slab extension vector!\n",
> +		 __func__, s->name))
> +		return NULL;
> +
> +	return slab_obj_exts(slab) + obj_to_index(s, slab, p);
> +}
> +
>  #else /* CONFIG_SLAB_OBJ_EXT */
>  
>  static inline struct slabobj_ext *slab_obj_exts(struct slab *slab)
> @@ -589,6 +629,32 @@ prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
>  
>  #endif /* CONFIG_SLAB_OBJ_EXT */
>  
> +#ifdef CONFIG_MEM_ALLOC_PROFILING
> +
> +static inline void alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab,
> +					void **p, int objects)

Only used from mm/slub.c so could move?

> +{
> +	struct slabobj_ext *obj_exts;
> +	int i;
> +
> +	obj_exts = slab_obj_exts(slab);
> +	if (!obj_exts)
> +		return;
> +
> +	for (i = 0; i < objects; i++) {
> +		unsigned int off = obj_to_index(s, slab, p[i]);
> +
> +		alloc_tag_sub(&obj_exts[off].ref, s->size);
> +	}
> +}
> +
> +#else
> +
> +static inline void alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab,
> +					void **p, int objects) {}
> +
> +#endif /* CONFIG_MEM_ALLOC_PROFILING */
> +
>  #ifdef CONFIG_MEMCG_KMEM
>  void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
>  		     enum node_stat_item idx, int nr);
> diff --git a/mm/slub.c b/mm/slub.c
> index 5dc7beda6c0d..a69b6b4c8df6 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -3826,6 +3826,7 @@ void slab_post_alloc_hook(struct kmem_cache *s,	struct obj_cgroup *objcg,
>  			  unsigned int orig_size)
>  {
>  	unsigned int zero_size = s->object_size;
> +	struct slabobj_ext *obj_exts;
>  	bool kasan_init = init;
>  	size_t i;
>  	gfp_t init_flags = flags & gfp_allowed_mask;
> @@ -3868,6 +3869,12 @@ void slab_post_alloc_hook(struct kmem_cache *s,	struct obj_cgroup *objcg,
>  		kmemleak_alloc_recursive(p[i], s->object_size, 1,
>  					 s->flags, init_flags);
>  		kmsan_slab_alloc(s, p[i], init_flags);
> +		obj_exts = prepare_slab_obj_exts_hook(s, flags, p[i]);
> +#ifdef CONFIG_MEM_ALLOC_PROFILING
> +		/* obj_exts can be allocated for other reasons */
> +		if (likely(obj_exts) && mem_alloc_profiling_enabled())
> +			alloc_tag_add(&obj_exts->ref, current->alloc_tag, s->size);
> +#endif

I think that like in the page allocator, this could be better guarded by
mem_alloc_profiling_enabled() as the outermost thing.

>  	}
>  
>  	memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
> @@ -4346,6 +4353,7 @@ void slab_free(struct kmem_cache *s, struct slab *slab, void *object,
>  	       unsigned long addr)
>  {
>  	memcg_slab_free_hook(s, slab, &object, 1);
> +	alloc_tagging_slab_free_hook(s, slab, &object, 1);

Same here, the static key is not even inside of this?

>  
>  	if (likely(slab_free_hook(s, object, slab_want_init_on_free(s))))
>  		do_slab_free(s, slab, object, object, 1, addr);
> @@ -4356,6 +4364,7 @@ void slab_free_bulk(struct kmem_cache *s, struct slab *slab, void *head,
>  		    void *tail, void **p, int cnt, unsigned long addr)
>  {
>  	memcg_slab_free_hook(s, slab, p, cnt);
> +	alloc_tagging_slab_free_hook(s, slab, p, cnt);

Ditto.

>  	/*
>  	 * With KASAN enabled slab_free_freelist_hook modifies the freelist
>  	 * to remove objects, whose reuse must be delayed.
Suren Baghdasaryan Feb. 27, 2024, 4:15 p.m. UTC | #2 
On Tue, Feb 27, 2024 at 5:07 AM Vlastimil Babka <vbabka@suse.cz> wrote:
>
>
>
> On 2/21/24 20:40, Suren Baghdasaryan wrote:
> > Account slab allocations using codetag reference embedded into slabobj_ext.
> >
> > Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> > Co-developed-by: Kent Overstreet <kent.overstreet@linux.dev>
> > Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
> > Reviewed-by: Kees Cook <keescook@chromium.org>
> > ---
> >  mm/slab.h | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  mm/slub.c |  9 ++++++++
> >  2 files changed, 75 insertions(+)
> >
> > diff --git a/mm/slab.h b/mm/slab.h
> > index 13b6ba2abd74..c4bd0d5348cb 100644
> > --- a/mm/slab.h
> > +++ b/mm/slab.h
> > @@ -567,6 +567,46 @@ static inline struct slabobj_ext *slab_obj_exts(struct slab *slab)
> >  int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s,
> >                       gfp_t gfp, bool new_slab);
> >
> > +static inline bool need_slab_obj_ext(void)
> > +{
> > +#ifdef CONFIG_MEM_ALLOC_PROFILING
> > +     if (mem_alloc_profiling_enabled())
> > +             return true;
> > +#endif
> > +     /*
> > +      * CONFIG_MEMCG_KMEM creates vector of obj_cgroup objects conditionally
> > +      * inside memcg_slab_post_alloc_hook. No other users for now.
> > +      */
> > +     return false;
> > +}
> > +
> > +static inline struct slabobj_ext *
> > +prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
> > +{
> > +     struct slab *slab;
> > +
> > +     if (!p)
> > +             return NULL;
> > +
> > +     if (!need_slab_obj_ext())
> > +             return NULL;
> > +
> > +     if (s->flags & SLAB_NO_OBJ_EXT)
> > +             return NULL;
> > +
> > +     if (flags & __GFP_NO_OBJ_EXT)
> > +             return NULL;
> > +
> > +     slab = virt_to_slab(p);
> > +     if (!slab_obj_exts(slab) &&
> > +         WARN(alloc_slab_obj_exts(slab, s, flags, false),
> > +              "%s, %s: Failed to create slab extension vector!\n",
> > +              __func__, s->name))
> > +             return NULL;
> > +
> > +     return slab_obj_exts(slab) + obj_to_index(s, slab, p);
> > +}
> > +
> >  #else /* CONFIG_SLAB_OBJ_EXT */
> >
> >  static inline struct slabobj_ext *slab_obj_exts(struct slab *slab)
> > @@ -589,6 +629,32 @@ prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
> >
> >  #endif /* CONFIG_SLAB_OBJ_EXT */
> >
> > +#ifdef CONFIG_MEM_ALLOC_PROFILING
> > +
> > +static inline void alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab,
> > +                                     void **p, int objects)
>
> Only used from mm/slub.c so could move?

Ack.

>
> > +{
> > +     struct slabobj_ext *obj_exts;
> > +     int i;
> > +
> > +     obj_exts = slab_obj_exts(slab);
> > +     if (!obj_exts)
> > +             return;
> > +
> > +     for (i = 0; i < objects; i++) {
> > +             unsigned int off = obj_to_index(s, slab, p[i]);
> > +
> > +             alloc_tag_sub(&obj_exts[off].ref, s->size);
> > +     }
> > +}
> > +
> > +#else
> > +
> > +static inline void alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab,
> > +                                     void **p, int objects) {}
> > +
> > +#endif /* CONFIG_MEM_ALLOC_PROFILING */
> > +
> >  #ifdef CONFIG_MEMCG_KMEM
> >  void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
> >                    enum node_stat_item idx, int nr);
> > diff --git a/mm/slub.c b/mm/slub.c
> > index 5dc7beda6c0d..a69b6b4c8df6 100644
> > --- a/mm/slub.c
> > +++ b/mm/slub.c
> > @@ -3826,6 +3826,7 @@ void slab_post_alloc_hook(struct kmem_cache *s, struct obj_cgroup *objcg,
> >                         unsigned int orig_size)
> >  {
> >       unsigned int zero_size = s->object_size;
> > +     struct slabobj_ext *obj_exts;
> >       bool kasan_init = init;
> >       size_t i;
> >       gfp_t init_flags = flags & gfp_allowed_mask;
> > @@ -3868,6 +3869,12 @@ void slab_post_alloc_hook(struct kmem_cache *s,        struct obj_cgroup *objcg,
> >               kmemleak_alloc_recursive(p[i], s->object_size, 1,
> >                                        s->flags, init_flags);
> >               kmsan_slab_alloc(s, p[i], init_flags);
> > +             obj_exts = prepare_slab_obj_exts_hook(s, flags, p[i]);
> > +#ifdef CONFIG_MEM_ALLOC_PROFILING
> > +             /* obj_exts can be allocated for other reasons */
> > +             if (likely(obj_exts) && mem_alloc_profiling_enabled())
> > +                     alloc_tag_add(&obj_exts->ref, current->alloc_tag, s->size);
> > +#endif
>
> I think that like in the page allocator, this could be better guarded by
> mem_alloc_profiling_enabled() as the outermost thing.

Oops, missed it. Will fix.

>
> >       }
> >
> >       memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
> > @@ -4346,6 +4353,7 @@ void slab_free(struct kmem_cache *s, struct slab *slab, void *object,
> >              unsigned long addr)
> >  {
> >       memcg_slab_free_hook(s, slab, &object, 1);
> > +     alloc_tagging_slab_free_hook(s, slab, &object, 1);
>
> Same here, the static key is not even inside of this?

Ack.

>
> >
> >       if (likely(slab_free_hook(s, object, slab_want_init_on_free(s))))
> >               do_slab_free(s, slab, object, object, 1, addr);
> > @@ -4356,6 +4364,7 @@ void slab_free_bulk(struct kmem_cache *s, struct slab *slab, void *head,
> >                   void *tail, void **p, int cnt, unsigned long addr)
> >  {
> >       memcg_slab_free_hook(s, slab, p, cnt);
> > +     alloc_tagging_slab_free_hook(s, slab, p, cnt);
>
> Ditto.

Ack.

>
> >       /*
> >        * With KASAN enabled slab_free_freelist_hook modifies the freelist
> >        * to remove objects, whose reuse must be delayed.
>
> --
> To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@android.com.
>
diff mbox series

Patch

diff --git a/mm/slab.h b/mm/slab.h
index 13b6ba2abd74..c4bd0d5348cb 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -567,6 +567,46 @@  static inline struct slabobj_ext *slab_obj_exts(struct slab *slab)
 int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s,
 			gfp_t gfp, bool new_slab);
 
+static inline bool need_slab_obj_ext(void)
+{
+#ifdef CONFIG_MEM_ALLOC_PROFILING
+	if (mem_alloc_profiling_enabled())
+		return true;
+#endif
+	/*
+	 * CONFIG_MEMCG_KMEM creates vector of obj_cgroup objects conditionally
+	 * inside memcg_slab_post_alloc_hook. No other users for now.
+	 */
+	return false;
+}
+
+static inline struct slabobj_ext *
+prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
+{
+	struct slab *slab;
+
+	if (!p)
+		return NULL;
+
+	if (!need_slab_obj_ext())
+		return NULL;
+
+	if (s->flags & SLAB_NO_OBJ_EXT)
+		return NULL;
+
+	if (flags & __GFP_NO_OBJ_EXT)
+		return NULL;
+
+	slab = virt_to_slab(p);
+	if (!slab_obj_exts(slab) &&
+	    WARN(alloc_slab_obj_exts(slab, s, flags, false),
+		 "%s, %s: Failed to create slab extension vector!\n",
+		 __func__, s->name))
+		return NULL;
+
+	return slab_obj_exts(slab) + obj_to_index(s, slab, p);
+}
+
 #else /* CONFIG_SLAB_OBJ_EXT */
 
 static inline struct slabobj_ext *slab_obj_exts(struct slab *slab)
@@ -589,6 +629,32 @@  prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
 
 #endif /* CONFIG_SLAB_OBJ_EXT */
 
+#ifdef CONFIG_MEM_ALLOC_PROFILING
+
+static inline void alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab,
+					void **p, int objects)
+{
+	struct slabobj_ext *obj_exts;
+	int i;
+
+	obj_exts = slab_obj_exts(slab);
+	if (!obj_exts)
+		return;
+
+	for (i = 0; i < objects; i++) {
+		unsigned int off = obj_to_index(s, slab, p[i]);
+
+		alloc_tag_sub(&obj_exts[off].ref, s->size);
+	}
+}
+
+#else
+
+static inline void alloc_tagging_slab_free_hook(struct kmem_cache *s, struct slab *slab,
+					void **p, int objects) {}
+
+#endif /* CONFIG_MEM_ALLOC_PROFILING */
+
 #ifdef CONFIG_MEMCG_KMEM
 void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
 		     enum node_stat_item idx, int nr);
diff --git a/mm/slub.c b/mm/slub.c
index 5dc7beda6c0d..a69b6b4c8df6 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3826,6 +3826,7 @@  void slab_post_alloc_hook(struct kmem_cache *s,	struct obj_cgroup *objcg,
 			  unsigned int orig_size)
 {
 	unsigned int zero_size = s->object_size;
+	struct slabobj_ext *obj_exts;
 	bool kasan_init = init;
 	size_t i;
 	gfp_t init_flags = flags & gfp_allowed_mask;
@@ -3868,6 +3869,12 @@  void slab_post_alloc_hook(struct kmem_cache *s,	struct obj_cgroup *objcg,
 		kmemleak_alloc_recursive(p[i], s->object_size, 1,
 					 s->flags, init_flags);
 		kmsan_slab_alloc(s, p[i], init_flags);
+		obj_exts = prepare_slab_obj_exts_hook(s, flags, p[i]);
+#ifdef CONFIG_MEM_ALLOC_PROFILING
+		/* obj_exts can be allocated for other reasons */
+		if (likely(obj_exts) && mem_alloc_profiling_enabled())
+			alloc_tag_add(&obj_exts->ref, current->alloc_tag, s->size);
+#endif
 	}
 
 	memcg_slab_post_alloc_hook(s, objcg, flags, size, p);
@@ -4346,6 +4353,7 @@  void slab_free(struct kmem_cache *s, struct slab *slab, void *object,
 	       unsigned long addr)
 {
 	memcg_slab_free_hook(s, slab, &object, 1);
+	alloc_tagging_slab_free_hook(s, slab, &object, 1);
 
 	if (likely(slab_free_hook(s, object, slab_want_init_on_free(s))))
 		do_slab_free(s, slab, object, object, 1, addr);
@@ -4356,6 +4364,7 @@  void slab_free_bulk(struct kmem_cache *s, struct slab *slab, void *head,
 		    void *tail, void **p, int cnt, unsigned long addr)
 {
 	memcg_slab_free_hook(s, slab, p, cnt);
+	alloc_tagging_slab_free_hook(s, slab, p, cnt);
 	/*
 	 * With KASAN enabled slab_free_freelist_hook modifies the freelist
 	 * to remove objects, whose reuse must be delayed.