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[PATCH v5 06/14] tools: Add sheaves support to testing infrastructure

Vlastimil Babka posted 14 patches 6 months, 3 weeks ago
There is a newer version of this series
[PATCH v5 06/14] tools: Add sheaves support to testing infrastructure
Posted by Vlastimil Babka 6 months, 3 weeks ago 
From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>

Allocate a sheaf and fill it to the count amount.  Does not fill to the
sheaf limit to detect incorrect allocation requests.

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
 tools/include/linux/slab.h   | 24 +++++++++++++
 tools/testing/shared/linux.c | 84 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 108 insertions(+)

diff --git a/tools/include/linux/slab.h b/tools/include/linux/slab.h
index d1444e79f2685edb828adbce8b3fbb500c0f8844..1962d7f1abee154e1cda5dba28aef213088dd198 100644
--- a/tools/include/linux/slab.h
+++ b/tools/include/linux/slab.h
@@ -23,6 +23,13 @@ enum slab_state {
 	FULL
 };
 
+struct slab_sheaf {
+	struct kmem_cache *cache;
+	unsigned int size;
+	unsigned int capacity;
+	void *objects[];
+};
+
 struct kmem_cache_args {
 	unsigned int align;
 	unsigned int sheaf_capacity;
@@ -80,4 +87,21 @@ void kmem_cache_free_bulk(struct kmem_cache *cachep, size_t size, void **list);
 int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
 			  void **list);
 
+struct slab_sheaf *
+kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size);
+
+void *
+kmem_cache_alloc_from_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf *sheaf);
+
+void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf *sheaf);
+int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf **sheafp, unsigned int size);
+
+static inline unsigned int kmem_cache_sheaf_size(struct slab_sheaf *sheaf)
+{
+	return sheaf->size;
+}
+
 #endif		/* _TOOLS_SLAB_H */
diff --git a/tools/testing/shared/linux.c b/tools/testing/shared/linux.c
index f998555a1b2af4a899a468a652b04622df459ed3..e0255f53159bd3a1325d49192283dd6790a5e3b8 100644
--- a/tools/testing/shared/linux.c
+++ b/tools/testing/shared/linux.c
@@ -181,6 +181,12 @@ int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
 	if (kmalloc_verbose)
 		pr_debug("Bulk alloc %zu\n", size);
 
+	if (cachep->exec_callback) {
+		if (cachep->callback)
+			cachep->callback(cachep->private);
+		cachep->exec_callback = false;
+	}
+
 	pthread_mutex_lock(&cachep->lock);
 	if (cachep->nr_objs >= size) {
 		struct radix_tree_node *node;
@@ -270,6 +276,84 @@ __kmem_cache_create_args(const char *name, unsigned int size,
 	return ret;
 }
 
+struct slab_sheaf *
+kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size)
+{
+	struct slab_sheaf *sheaf;
+	unsigned int capacity;
+
+	if (size > s->sheaf_capacity)
+		capacity = size;
+	else
+		capacity = s->sheaf_capacity;
+
+	sheaf = malloc(sizeof(*sheaf) + sizeof(void *) * s->sheaf_capacity * capacity);
+	if (!sheaf) {
+		return NULL;
+	}
+
+	memset(sheaf, 0, size);
+	sheaf->cache = s;
+	sheaf->capacity = capacity;
+	sheaf->size = kmem_cache_alloc_bulk(s, gfp, size, sheaf->objects);
+	if (!sheaf->size) {
+		free(sheaf);
+		return NULL;
+	}
+
+	return sheaf;
+}
+
+int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
+		 struct slab_sheaf **sheafp, unsigned int size)
+{
+	struct slab_sheaf *sheaf = *sheafp;
+	int refill;
+
+	if (sheaf->size >= size)
+		return 0;
+
+	if (size > sheaf->capacity) {
+		sheaf = kmem_cache_prefill_sheaf(s, gfp, size);
+		if (!sheaf)
+			return -ENOMEM;
+
+		kmem_cache_return_sheaf(s, gfp, *sheafp);
+		*sheafp = sheaf;
+		return 0;
+	}
+
+	refill = kmem_cache_alloc_bulk(s, gfp, size - sheaf->size,
+				       &sheaf->objects[sheaf->size]);
+	if (!refill)
+		return -ENOMEM;
+
+	sheaf->size += refill;
+	return 0;
+}
+
+void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
+		 struct slab_sheaf *sheaf)
+{
+	if (sheaf->size) {
+		//s->non_kernel += sheaf->size;
+		kmem_cache_free_bulk(s, sheaf->size, &sheaf->objects[0]);
+	}
+	free(sheaf);
+}
+
+void *
+kmem_cache_alloc_from_sheaf(struct kmem_cache *s, gfp_t gfp,
+		struct slab_sheaf *sheaf)
+{
+	if (sheaf->size == 0) {
+		printf("Nothing left in sheaf!\n");
+		return NULL;
+	}
+
+	return sheaf->objects[--sheaf->size];
+}
+
 /*
  * Test the test infrastructure for kem_cache_alloc/free and bulk counterparts.
  */

-- 
2.50.1
Re: [PATCH v5 06/14] tools: Add sheaves support to testing infrastructure
Posted by Suren Baghdasaryan 5 months, 3 weeks ago 
On Wed, Jul 23, 2025 at 6:35 AM Vlastimil Babka <vbabka@suse.cz> wrote:
>
> From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
>
> Allocate a sheaf and fill it to the count amount.  Does not fill to the
> sheaf limit to detect incorrect allocation requests.
>
> Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
> ---
>  tools/include/linux/slab.h   | 24 +++++++++++++
>  tools/testing/shared/linux.c | 84 ++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 108 insertions(+)
>
> diff --git a/tools/include/linux/slab.h b/tools/include/linux/slab.h
> index d1444e79f2685edb828adbce8b3fbb500c0f8844..1962d7f1abee154e1cda5dba28aef213088dd198 100644
> --- a/tools/include/linux/slab.h
> +++ b/tools/include/linux/slab.h
> @@ -23,6 +23,13 @@ enum slab_state {
>         FULL
>  };
>
> +struct slab_sheaf {
> +       struct kmem_cache *cache;
> +       unsigned int size;
> +       unsigned int capacity;
> +       void *objects[];
> +};
> +
>  struct kmem_cache_args {
>         unsigned int align;
>         unsigned int sheaf_capacity;
> @@ -80,4 +87,21 @@ void kmem_cache_free_bulk(struct kmem_cache *cachep, size_t size, void **list);
>  int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
>                           void **list);
>
> +struct slab_sheaf *
> +kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size);
> +
> +void *
> +kmem_cache_alloc_from_sheaf(struct kmem_cache *s, gfp_t gfp,
> +               struct slab_sheaf *sheaf);
> +
> +void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
> +               struct slab_sheaf *sheaf);
> +int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
> +               struct slab_sheaf **sheafp, unsigned int size);
> +
> +static inline unsigned int kmem_cache_sheaf_size(struct slab_sheaf *sheaf)
> +{
> +       return sheaf->size;
> +}
> +
>  #endif         /* _TOOLS_SLAB_H */
> diff --git a/tools/testing/shared/linux.c b/tools/testing/shared/linux.c
> index f998555a1b2af4a899a468a652b04622df459ed3..e0255f53159bd3a1325d49192283dd6790a5e3b8 100644
> --- a/tools/testing/shared/linux.c
> +++ b/tools/testing/shared/linux.c
> @@ -181,6 +181,12 @@ int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
>         if (kmalloc_verbose)
>                 pr_debug("Bulk alloc %zu\n", size);
>
> +       if (cachep->exec_callback) {
> +               if (cachep->callback)
> +                       cachep->callback(cachep->private);
> +               cachep->exec_callback = false;
> +       }
> +
>         pthread_mutex_lock(&cachep->lock);
>         if (cachep->nr_objs >= size) {
>                 struct radix_tree_node *node;
> @@ -270,6 +276,84 @@ __kmem_cache_create_args(const char *name, unsigned int size,
>         return ret;
>  }
>
> +struct slab_sheaf *
> +kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size)
> +{
> +       struct slab_sheaf *sheaf;
> +       unsigned int capacity;
> +
> +       if (size > s->sheaf_capacity)
> +               capacity = size;
> +       else
> +               capacity = s->sheaf_capacity;

nit:
capacity = max(size, s->sheaf_capacity);

> +
> +       sheaf = malloc(sizeof(*sheaf) + sizeof(void *) * s->sheaf_capacity * capacity);

Should this really be `sizeof(void *) * s->sheaf_capacity * capacity`
or just `sizeof(void *) * capacity` ?


> +       if (!sheaf) {
> +               return NULL;
> +       }
> +
> +       memset(sheaf, 0, size);
> +       sheaf->cache = s;
> +       sheaf->capacity = capacity;
> +       sheaf->size = kmem_cache_alloc_bulk(s, gfp, size, sheaf->objects);
> +       if (!sheaf->size) {
> +               free(sheaf);
> +               return NULL;
> +       }
> +
> +       return sheaf;
> +}
> +
> +int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
> +                struct slab_sheaf **sheafp, unsigned int size)
> +{
> +       struct slab_sheaf *sheaf = *sheafp;
> +       int refill;
> +
> +       if (sheaf->size >= size)
> +               return 0;
> +
> +       if (size > sheaf->capacity) {
> +               sheaf = kmem_cache_prefill_sheaf(s, gfp, size);
> +               if (!sheaf)
> +                       return -ENOMEM;
> +
> +               kmem_cache_return_sheaf(s, gfp, *sheafp);
> +               *sheafp = sheaf;
> +               return 0;
> +       }
> +
> +       refill = kmem_cache_alloc_bulk(s, gfp, size - sheaf->size,
> +                                      &sheaf->objects[sheaf->size]);
> +       if (!refill)
> +               return -ENOMEM;
> +
> +       sheaf->size += refill;
> +       return 0;
> +}
> +
> +void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
> +                struct slab_sheaf *sheaf)
> +{
> +       if (sheaf->size) {
> +               //s->non_kernel += sheaf->size;

Above comment seems obsolete.

> +               kmem_cache_free_bulk(s, sheaf->size, &sheaf->objects[0]);
> +       }
> +       free(sheaf);
> +}
> +
> +void *
> +kmem_cache_alloc_from_sheaf(struct kmem_cache *s, gfp_t gfp,
> +               struct slab_sheaf *sheaf)
> +{
> +       if (sheaf->size == 0) {
> +               printf("Nothing left in sheaf!\n");
> +               return NULL;
> +       }
> +

Should we clear sheaf->objects[sheaf->size] for additional safety?

> +       return sheaf->objects[--sheaf->size];
> +}
> +
>  /*
>   * Test the test infrastructure for kem_cache_alloc/free and bulk counterparts.
>   */
>
> --
> 2.50.1
>
Re: [PATCH v5 06/14] tools: Add sheaves support to testing infrastructure
Posted by Vlastimil Babka 5 months, 2 weeks ago 
On 8/22/25 18:56, Suren Baghdasaryan wrote:
>> @@ -270,6 +276,84 @@ __kmem_cache_create_args(const char *name, unsigned int size,
>>         return ret;
>>  }
>>
>> +struct slab_sheaf *
>> +kmem_cache_prefill_sheaf(struct kmem_cache *s, gfp_t gfp, unsigned int size)
>> +{
>> +       struct slab_sheaf *sheaf;
>> +       unsigned int capacity;
>> +
>> +       if (size > s->sheaf_capacity)
>> +               capacity = size;
>> +       else
>> +               capacity = s->sheaf_capacity;
> 
> nit:
> capacity = max(size, s->sheaf_capacity);

OK

>> +
>> +       sheaf = malloc(sizeof(*sheaf) + sizeof(void *) * s->sheaf_capacity * capacity);
> 
> Should this really be `sizeof(void *) * s->sheaf_capacity * capacity`
> or just `sizeof(void *) * capacity` ?

Right, so the whole thing should be:
sizeof(*sheaf) + sizeof(void *) * capacity

> 
>> +       if (!sheaf) {
>> +               return NULL;
>> +       }
>> +
>> +       memset(sheaf, 0, size);

This is also wrong, so I'm changing it to calloc(1, ...) to get the zeroing
there.

>> +       sheaf->cache = s;
>> +       sheaf->capacity = capacity;
>> +       sheaf->size = kmem_cache_alloc_bulk(s, gfp, size, sheaf->objects);
>> +       if (!sheaf->size) {
>> +               free(sheaf);
>> +               return NULL;
>> +       }
>> +
>> +       return sheaf;
>> +}
>> +
>> +int kmem_cache_refill_sheaf(struct kmem_cache *s, gfp_t gfp,
>> +                struct slab_sheaf **sheafp, unsigned int size)
>> +{
>> +       struct slab_sheaf *sheaf = *sheafp;
>> +       int refill;
>> +
>> +       if (sheaf->size >= size)
>> +               return 0;
>> +
>> +       if (size > sheaf->capacity) {
>> +               sheaf = kmem_cache_prefill_sheaf(s, gfp, size);
>> +               if (!sheaf)
>> +                       return -ENOMEM;
>> +
>> +               kmem_cache_return_sheaf(s, gfp, *sheafp);
>> +               *sheafp = sheaf;
>> +               return 0;
>> +       }
>> +
>> +       refill = kmem_cache_alloc_bulk(s, gfp, size - sheaf->size,
>> +                                      &sheaf->objects[sheaf->size]);
>> +       if (!refill)
>> +               return -ENOMEM;
>> +
>> +       sheaf->size += refill;
>> +       return 0;
>> +}
>> +
>> +void kmem_cache_return_sheaf(struct kmem_cache *s, gfp_t gfp,
>> +                struct slab_sheaf *sheaf)
>> +{
>> +       if (sheaf->size) {
>> +               //s->non_kernel += sheaf->size;
> 
> Above comment seems obsolete.

Ack.

> 
>> +               kmem_cache_free_bulk(s, sheaf->size, &sheaf->objects[0]);
>> +       }
>> +       free(sheaf);
>> +}
>> +
>> +void *
>> +kmem_cache_alloc_from_sheaf(struct kmem_cache *s, gfp_t gfp,
>> +               struct slab_sheaf *sheaf)
>> +{
>> +       if (sheaf->size == 0) {
>> +               printf("Nothing left in sheaf!\n");
>> +               return NULL;
>> +       }
>> +
> 
> Should we clear sheaf->objects[sheaf->size] for additional safety?

OK.
>> +       return sheaf->objects[--sheaf->size];
>> +}
>> +
>>  /*
>>   * Test the test infrastructure for kem_cache_alloc/free and bulk counterparts.
>>   */
>>
>> --
>> 2.50.1
>>

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