diff mbox series

[for-next] rdma_rxe: address an issue with hardened user copy

Message ID 20200825165836.27477-1-rpearson@hpe.com (mailing list archive)
State Superseded
Delegated to: Jason Gunthorpe
Headers show
Series [for-next] rdma_rxe: address an issue with hardened user copy | expand

Commit Message

Bob Pearson Aug. 25, 2020, 4:58 p.m. UTC
Change rxe pools to use kzalloc instead of kmem_cache to allocate
memory for rxe objects.

Signed-off-by: Bob Pearson <rpearson@hpe.com>
---
 drivers/infiniband/sw/rxe/rxe.c      |  8 ----
 drivers/infiniband/sw/rxe/rxe_pool.c | 60 +---------------------------
 drivers/infiniband/sw/rxe/rxe_pool.h |  7 ----
 3 files changed, 2 insertions(+), 73 deletions(-)

Comments

Zhu Yanjun Aug. 27, 2020, 1:21 a.m. UTC | #1
On 8/26/2020 12:58 AM, Bob Pearson wrote:
> Change rxe pools to use kzalloc instead of kmem_cache to allocate

Why do you use kzalloc instead of kmem_cache? For performance or some bugs?

Zhu Yanjun

> memory for rxe objects.
>
> Signed-off-by: Bob Pearson <rpearson@hpe.com>
> ---
>   drivers/infiniband/sw/rxe/rxe.c      |  8 ----
>   drivers/infiniband/sw/rxe/rxe_pool.c | 60 +---------------------------
>   drivers/infiniband/sw/rxe/rxe_pool.h |  7 ----
>   3 files changed, 2 insertions(+), 73 deletions(-)
>
> diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c
> index cc395da13eff..a1ff70e0b1f8 100644
> --- a/drivers/infiniband/sw/rxe/rxe.c
> +++ b/drivers/infiniband/sw/rxe/rxe.c
> @@ -277,13 +277,6 @@ static int __init rxe_module_init(void)
>   {
>   	int err;
>   
> -	/* initialize slab caches for managed objects */
> -	err = rxe_cache_init();
> -	if (err) {
> -		pr_err("unable to init object pools\n");
> -		return err;
> -	}
> -
>   	err = rxe_net_init();
>   	if (err)
>   		return err;
> @@ -298,7 +291,6 @@ static void __exit rxe_module_exit(void)
>   	rdma_link_unregister(&rxe_link_ops);
>   	ib_unregister_driver(RDMA_DRIVER_RXE);
>   	rxe_net_exit();
> -	rxe_cache_exit();
>   
>   	pr_info("unloaded\n");
>   }
> diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
> index c0fab4a65f9e..70fc9f7a25b6 100644
> --- a/drivers/infiniband/sw/rxe/rxe_pool.c
> +++ b/drivers/infiniband/sw/rxe/rxe_pool.c
> @@ -84,62 +84,6 @@ static inline const char *pool_name(struct rxe_pool *pool)
>   	return rxe_type_info[pool->type].name;
>   }
>   
> -static inline struct kmem_cache *pool_cache(struct rxe_pool *pool)
> -{
> -	return rxe_type_info[pool->type].cache;
> -}
> -
> -static void rxe_cache_clean(size_t cnt)
> -{
> -	int i;
> -	struct rxe_type_info *type;
> -
> -	for (i = 0; i < cnt; i++) {
> -		type = &rxe_type_info[i];
> -		if (!(type->flags & RXE_POOL_NO_ALLOC)) {
> -			kmem_cache_destroy(type->cache);
> -			type->cache = NULL;
> -		}
> -	}
> -}
> -
> -int rxe_cache_init(void)
> -{
> -	int err;
> -	int i;
> -	size_t size;
> -	struct rxe_type_info *type;
> -
> -	for (i = 0; i < RXE_NUM_TYPES; i++) {
> -		type = &rxe_type_info[i];
> -		size = ALIGN(type->size, RXE_POOL_ALIGN);
> -		if (!(type->flags & RXE_POOL_NO_ALLOC)) {
> -			type->cache =
> -				kmem_cache_create(type->name, size,
> -						  RXE_POOL_ALIGN,
> -						  RXE_POOL_CACHE_FLAGS, NULL);
> -			if (!type->cache) {
> -				pr_err("Unable to init kmem cache for %s\n",
> -				       type->name);
> -				err = -ENOMEM;
> -				goto err1;
> -			}
> -		}
> -	}
> -
> -	return 0;
> -
> -err1:
> -	rxe_cache_clean(i);
> -
> -	return err;
> -}
> -
> -void rxe_cache_exit(void)
> -{
> -	rxe_cache_clean(RXE_NUM_TYPES);
> -}
> -
>   static int rxe_pool_init_index(struct rxe_pool *pool, u32 max, u32 min)
>   {
>   	int err = 0;
> @@ -381,7 +325,7 @@ void *rxe_alloc(struct rxe_pool *pool)
>   	if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
>   		goto out_cnt;
>   
> -	elem = kmem_cache_zalloc(pool_cache(pool),
> +	elem = kzalloc(rxe_type_info[pool->type].size,
>   				 (pool->flags & RXE_POOL_ATOMIC) ?
>   				 GFP_ATOMIC : GFP_KERNEL);
>   	if (!elem)
> @@ -443,7 +387,7 @@ void rxe_elem_release(struct kref *kref)
>   		pool->cleanup(elem);
>   
>   	if (!(pool->flags & RXE_POOL_NO_ALLOC))
> -		kmem_cache_free(pool_cache(pool), elem);
> +		kfree(elem);
>   	atomic_dec(&pool->num_elem);
>   	ib_device_put(&pool->rxe->ib_dev);
>   	rxe_pool_put(pool);
> diff --git a/drivers/infiniband/sw/rxe/rxe_pool.h b/drivers/infiniband/sw/rxe/rxe_pool.h
> index 64d92be3f060..3d722aae5f15 100644
> --- a/drivers/infiniband/sw/rxe/rxe_pool.h
> +++ b/drivers/infiniband/sw/rxe/rxe_pool.h
> @@ -42,7 +42,6 @@ struct rxe_type_info {
>   	u32			min_index;
>   	size_t			key_offset;
>   	size_t			key_size;
> -	struct kmem_cache	*cache;
>   };
>   
>   extern struct rxe_type_info rxe_type_info[];
> @@ -96,12 +95,6 @@ struct rxe_pool {
>   	} key;
>   };
>   
> -/* initialize slab caches for managed objects */
> -int rxe_cache_init(void);
> -
> -/* cleanup slab caches for managed objects */
> -void rxe_cache_exit(void);
> -
>   /* initialize a pool of objects with given limit on
>    * number of elements. gets parameters from rxe_type_info
>    * pool elements will be allocated out of a slab cache
Bob Pearson Aug. 27, 2020, 1:30 a.m. UTC | #2
On 8/26/20 8:21 PM, Zhu Yanjun wrote:
> On 8/26/2020 12:58 AM, Bob Pearson wrote:
>> Change rxe pools to use kzalloc instead of kmem_cache to allocate
> 
> Why do you use kzalloc instead of kmem_cache? For performance or some bugs?
> 
> Zhu Yanjun
> 
>> memory for rxe objects.
>>
>> Signed-off-by: Bob Pearson <rpearson@hpe.com>
>> ---
>>   drivers/infiniband/sw/rxe/rxe.c      |  8 ----
>>   drivers/infiniband/sw/rxe/rxe_pool.c | 60 +---------------------------
>>   drivers/infiniband/sw/rxe/rxe_pool.h |  7 ----
>>   3 files changed, 2 insertions(+), 73 deletions(-)
>>
>> diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c
>> index cc395da13eff..a1ff70e0b1f8 100644
>> --- a/drivers/infiniband/sw/rxe/rxe.c
>> +++ b/drivers/infiniband/sw/rxe/rxe.c
>> @@ -277,13 +277,6 @@ static int __init rxe_module_init(void)
>>   {
>>       int err;
>>   -    /* initialize slab caches for managed objects */
>> -    err = rxe_cache_init();
>> -    if (err) {
>> -        pr_err("unable to init object pools\n");
>> -        return err;
>> -    }
>> -
>>       err = rxe_net_init();
>>       if (err)
>>           return err;
>> @@ -298,7 +291,6 @@ static void __exit rxe_module_exit(void)
>>       rdma_link_unregister(&rxe_link_ops);
>>       ib_unregister_driver(RDMA_DRIVER_RXE);
>>       rxe_net_exit();
>> -    rxe_cache_exit();
>>         pr_info("unloaded\n");
>>   }
>> diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
>> index c0fab4a65f9e..70fc9f7a25b6 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_pool.c
>> +++ b/drivers/infiniband/sw/rxe/rxe_pool.c
>> @@ -84,62 +84,6 @@ static inline const char *pool_name(struct rxe_pool *pool)
>>       return rxe_type_info[pool->type].name;
>>   }
>>   -static inline struct kmem_cache *pool_cache(struct rxe_pool *pool)
>> -{
>> -    return rxe_type_info[pool->type].cache;
>> -}
>> -
>> -static void rxe_cache_clean(size_t cnt)
>> -{
>> -    int i;
>> -    struct rxe_type_info *type;
>> -
>> -    for (i = 0; i < cnt; i++) {
>> -        type = &rxe_type_info[i];
>> -        if (!(type->flags & RXE_POOL_NO_ALLOC)) {
>> -            kmem_cache_destroy(type->cache);
>> -            type->cache = NULL;
>> -        }
>> -    }
>> -}
>> -
>> -int rxe_cache_init(void)
>> -{
>> -    int err;
>> -    int i;
>> -    size_t size;
>> -    struct rxe_type_info *type;
>> -
>> -    for (i = 0; i < RXE_NUM_TYPES; i++) {
>> -        type = &rxe_type_info[i];
>> -        size = ALIGN(type->size, RXE_POOL_ALIGN);
>> -        if (!(type->flags & RXE_POOL_NO_ALLOC)) {
>> -            type->cache =
>> -                kmem_cache_create(type->name, size,
>> -                          RXE_POOL_ALIGN,
>> -                          RXE_POOL_CACHE_FLAGS, NULL);
>> -            if (!type->cache) {
>> -                pr_err("Unable to init kmem cache for %s\n",
>> -                       type->name);
>> -                err = -ENOMEM;
>> -                goto err1;
>> -            }
>> -        }
>> -    }
>> -
>> -    return 0;
>> -
>> -err1:
>> -    rxe_cache_clean(i);
>> -
>> -    return err;
>> -}
>> -
>> -void rxe_cache_exit(void)
>> -{
>> -    rxe_cache_clean(RXE_NUM_TYPES);
>> -}
>> -
>>   static int rxe_pool_init_index(struct rxe_pool *pool, u32 max, u32 min)
>>   {
>>       int err = 0;
>> @@ -381,7 +325,7 @@ void *rxe_alloc(struct rxe_pool *pool)
>>       if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
>>           goto out_cnt;
>>   -    elem = kmem_cache_zalloc(pool_cache(pool),
>> +    elem = kzalloc(rxe_type_info[pool->type].size,
>>                    (pool->flags & RXE_POOL_ATOMIC) ?
>>                    GFP_ATOMIC : GFP_KERNEL);
>>       if (!elem)
>> @@ -443,7 +387,7 @@ void rxe_elem_release(struct kref *kref)
>>           pool->cleanup(elem);
>>         if (!(pool->flags & RXE_POOL_NO_ALLOC))
>> -        kmem_cache_free(pool_cache(pool), elem);
>> +        kfree(elem);
>>       atomic_dec(&pool->num_elem);
>>       ib_device_put(&pool->rxe->ib_dev);
>>       rxe_pool_put(pool);
>> diff --git a/drivers/infiniband/sw/rxe/rxe_pool.h b/drivers/infiniband/sw/rxe/rxe_pool.h
>> index 64d92be3f060..3d722aae5f15 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_pool.h
>> +++ b/drivers/infiniband/sw/rxe/rxe_pool.h
>> @@ -42,7 +42,6 @@ struct rxe_type_info {
>>       u32            min_index;
>>       size_t            key_offset;
>>       size_t            key_size;
>> -    struct kmem_cache    *cache;
>>   };
>>     extern struct rxe_type_info rxe_type_info[];
>> @@ -96,12 +95,6 @@ struct rxe_pool {
>>       } key;
>>   };
>>   -/* initialize slab caches for managed objects */
>> -int rxe_cache_init(void);
>> -
>> -/* cleanup slab caches for managed objects */
>> -void rxe_cache_exit(void);
>> -
>>   /* initialize a pool of objects with given limit on
>>    * number of elements. gets parameters from rxe_type_info
>>    * pool elements will be allocated out of a slab cache
> 
> 
There is a regression in rxe caused by the hardened usercopy patches. It leads to a kernel warning the first time a QP is created each boot. The origin has been discussed in several emails between Leon myself and the list. There are a lot of ways to eliminate the warning but so far there has been resistance to any of these fixes. As far as I can tell there is no performance hit from moving from kmem_cache to kzalloc. (kzalloc and kmalloc just use pre defined caches with objects that are powers of 2 in size.) I am waiting for Leon to express an opinion on this solution. He also has a proposal to allocate QP objects in the core (like PD, etc).

Bob
Leon Romanovsky Aug. 27, 2020, 7:02 a.m. UTC | #3
On Tue, Aug 25, 2020 at 11:58:37AM -0500, Bob Pearson wrote:
> Change rxe pools to use kzalloc instead of kmem_cache to allocate
> memory for rxe objects.
>
> Signed-off-by: Bob Pearson <rpearson@hpe.com>
> ---
>  drivers/infiniband/sw/rxe/rxe.c      |  8 ----
>  drivers/infiniband/sw/rxe/rxe_pool.c | 60 +---------------------------
>  drivers/infiniband/sw/rxe/rxe_pool.h |  7 ----
>  3 files changed, 2 insertions(+), 73 deletions(-)
>

I liked this solution.

Thanks,
Acked-by: Leon Romanovsky <leonro@nvidia.com>

BTW, didn't test/"review deeply" the patch so take my Acked-by with grain of salt.
Jason Gunthorpe Aug. 27, 2020, 1:58 p.m. UTC | #4
On Tue, Aug 25, 2020 at 11:58:37AM -0500, Bob Pearson wrote:
> Change rxe pools to use kzalloc instead of kmem_cache to allocate
> memory for rxe objects.
> 
> Signed-off-by: Bob Pearson <rpearson@hpe.com>
>  drivers/infiniband/sw/rxe/rxe.c      |  8 ----
>  drivers/infiniband/sw/rxe/rxe_pool.c | 60 +---------------------------
>  drivers/infiniband/sw/rxe/rxe_pool.h |  7 ----
>  3 files changed, 2 insertions(+), 73 deletions(-)

It doesn't apply:

Applying: rdma_rxe: address an issue with hardened user copy
error: sha1 information is lacking or useless (drivers/infiniband/sw/rxe/rxe.c).
error: could not build fake ancestor
Patch failed at 0001 rdma_rxe: address an issue with hardened user copy
hint: Use 'git am --show-current-patch=diff' to see the failed patch
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

Pleae generate patches against a v5.x tag or rdma for-next

Jason
Bob Pearson Aug. 27, 2020, 4:43 p.m. UTC | #5
On 8/27/20 8:58 AM, Jason Gunthorpe wrote:
> On Tue, Aug 25, 2020 at 11:58:37AM -0500, Bob Pearson wrote:
>> Change rxe pools to use kzalloc instead of kmem_cache to allocate
>> memory for rxe objects.
>>
>> Signed-off-by: Bob Pearson <rpearson@hpe.com>
>>  drivers/infiniband/sw/rxe/rxe.c      |  8 ----
>>  drivers/infiniband/sw/rxe/rxe_pool.c | 60 +---------------------------
>>  drivers/infiniband/sw/rxe/rxe_pool.h |  7 ----
>>  3 files changed, 2 insertions(+), 73 deletions(-)
> 
> It doesn't apply:
> 
> Applying: rdma_rxe: address an issue with hardened user copy
> error: sha1 information is lacking or useless (drivers/infiniband/sw/rxe/rxe.c).
> error: could not build fake ancestor
> Patch failed at 0001 rdma_rxe: address an issue with hardened user copy
> hint: Use 'git am --show-current-patch=diff' to see the failed patch
> When you have resolved this problem, run "git am --continue".
> If you prefer to skip this patch, run "git am --skip" instead.
> To restore the original branch and stop patching, run "git am --abort".
> 
> Pleae generate patches against a v5.x tag or rdma for-next
> 
> Jason
> 
I fixed it and sent it again.

Applies to today's for-next branch. It is independent from the SPDX patch but the line numbers will move a bunch. Hope that doesn't break it.
diff mbox series

Patch

diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c
index cc395da13eff..a1ff70e0b1f8 100644
--- a/drivers/infiniband/sw/rxe/rxe.c
+++ b/drivers/infiniband/sw/rxe/rxe.c
@@ -277,13 +277,6 @@  static int __init rxe_module_init(void)
 {
 	int err;
 
-	/* initialize slab caches for managed objects */
-	err = rxe_cache_init();
-	if (err) {
-		pr_err("unable to init object pools\n");
-		return err;
-	}
-
 	err = rxe_net_init();
 	if (err)
 		return err;
@@ -298,7 +291,6 @@  static void __exit rxe_module_exit(void)
 	rdma_link_unregister(&rxe_link_ops);
 	ib_unregister_driver(RDMA_DRIVER_RXE);
 	rxe_net_exit();
-	rxe_cache_exit();
 
 	pr_info("unloaded\n");
 }
diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
index c0fab4a65f9e..70fc9f7a25b6 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.c
+++ b/drivers/infiniband/sw/rxe/rxe_pool.c
@@ -84,62 +84,6 @@  static inline const char *pool_name(struct rxe_pool *pool)
 	return rxe_type_info[pool->type].name;
 }
 
-static inline struct kmem_cache *pool_cache(struct rxe_pool *pool)
-{
-	return rxe_type_info[pool->type].cache;
-}
-
-static void rxe_cache_clean(size_t cnt)
-{
-	int i;
-	struct rxe_type_info *type;
-
-	for (i = 0; i < cnt; i++) {
-		type = &rxe_type_info[i];
-		if (!(type->flags & RXE_POOL_NO_ALLOC)) {
-			kmem_cache_destroy(type->cache);
-			type->cache = NULL;
-		}
-	}
-}
-
-int rxe_cache_init(void)
-{
-	int err;
-	int i;
-	size_t size;
-	struct rxe_type_info *type;
-
-	for (i = 0; i < RXE_NUM_TYPES; i++) {
-		type = &rxe_type_info[i];
-		size = ALIGN(type->size, RXE_POOL_ALIGN);
-		if (!(type->flags & RXE_POOL_NO_ALLOC)) {
-			type->cache =
-				kmem_cache_create(type->name, size,
-						  RXE_POOL_ALIGN,
-						  RXE_POOL_CACHE_FLAGS, NULL);
-			if (!type->cache) {
-				pr_err("Unable to init kmem cache for %s\n",
-				       type->name);
-				err = -ENOMEM;
-				goto err1;
-			}
-		}
-	}
-
-	return 0;
-
-err1:
-	rxe_cache_clean(i);
-
-	return err;
-}
-
-void rxe_cache_exit(void)
-{
-	rxe_cache_clean(RXE_NUM_TYPES);
-}
-
 static int rxe_pool_init_index(struct rxe_pool *pool, u32 max, u32 min)
 {
 	int err = 0;
@@ -381,7 +325,7 @@  void *rxe_alloc(struct rxe_pool *pool)
 	if (atomic_inc_return(&pool->num_elem) > pool->max_elem)
 		goto out_cnt;
 
-	elem = kmem_cache_zalloc(pool_cache(pool),
+	elem = kzalloc(rxe_type_info[pool->type].size,
 				 (pool->flags & RXE_POOL_ATOMIC) ?
 				 GFP_ATOMIC : GFP_KERNEL);
 	if (!elem)
@@ -443,7 +387,7 @@  void rxe_elem_release(struct kref *kref)
 		pool->cleanup(elem);
 
 	if (!(pool->flags & RXE_POOL_NO_ALLOC))
-		kmem_cache_free(pool_cache(pool), elem);
+		kfree(elem);
 	atomic_dec(&pool->num_elem);
 	ib_device_put(&pool->rxe->ib_dev);
 	rxe_pool_put(pool);
diff --git a/drivers/infiniband/sw/rxe/rxe_pool.h b/drivers/infiniband/sw/rxe/rxe_pool.h
index 64d92be3f060..3d722aae5f15 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.h
+++ b/drivers/infiniband/sw/rxe/rxe_pool.h
@@ -42,7 +42,6 @@  struct rxe_type_info {
 	u32			min_index;
 	size_t			key_offset;
 	size_t			key_size;
-	struct kmem_cache	*cache;
 };
 
 extern struct rxe_type_info rxe_type_info[];
@@ -96,12 +95,6 @@  struct rxe_pool {
 	} key;
 };
 
-/* initialize slab caches for managed objects */
-int rxe_cache_init(void);
-
-/* cleanup slab caches for managed objects */
-void rxe_cache_exit(void);
-
 /* initialize a pool of objects with given limit on
  * number of elements. gets parameters from rxe_type_info
  * pool elements will be allocated out of a slab cache