Use rte_malloc in application

Use rte_malloc in application

[Rohit Saini (Stellus)]

Hi,
I have a use case in my application where I need to implement my own memory manager, rather than doing malloc/free everytime to kernel.
Instead of writing my own memory manager, I am thinking to use dpdk rte_malloc or rte_mempool. Please let me know if this is a good idea.

Also,

my_node_t *data_ptr = (my_node_t *) (uintptr_t) rte_malloc(NULL, sizeof(my_node_t), 0);

data_ptr is pointing to some invalid memory.  Am I doing anything wrong here?


Thanks,
Rohit

Re: Use rte_malloc in application

[Rohit Saini (Stellus)]

With below code, I am getting this warning.

warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]

my_node_t *data_ptr = (my_node_t *) rte_malloc(NULL, sizeof(my_node_t), 0);

Thanks,
Rohit

-----Original Message-----
From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Rohit Saini (Stellus)
Sent: Thursday, August 03, 2017 11:28 AM
To: 'dev@dpdk.org' <dev@dpdk.org>
Subject: [dpdk-dev] Use rte_malloc in application

Hi,
I have a use case in my application where I need to implement my own memory manager, rather than doing malloc/free everytime to kernel.
Instead of writing my own memory manager, I am thinking to use dpdk rte_malloc or rte_mempool. Please let me know if this is a good idea.

Also,

my_node_t *data_ptr = (my_node_t *) (uintptr_t) rte_malloc(NULL, sizeof(my_node_t), 0);

data_ptr is pointing to some invalid memory.  Am I doing anything wrong here?


Thanks,
Rohit

Re: Use rte_malloc in application

[Sergio Gonzalez Monroy]

On 03/08/2017 07:12, Rohit Saini (Stellus) wrote:
> With below code, I am getting this warning.
>
> warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
>
> my_node_t *data_ptr = (my_node_t *) rte_malloc(NULL, sizeof(my_node_t), 0);

As far as I can see, the syntax looks correct.

How are you building/linking your application?

I would suggest to modify the DPDK examples/helloworld application to 
just do a simple rte_malloc as a first step.

Thanks,
Sergio


> Thanks,
> Rohit
>
> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Rohit Saini (Stellus)
> Sent: Thursday, August 03, 2017 11:28 AM
> To: 'dev@dpdk.org' <dev@dpdk.org>
> Subject: [dpdk-dev] Use rte_malloc in application
>
> Hi,
> I have a use case in my application where I need to implement my own memory manager, rather than doing malloc/free everytime to kernel.
> Instead of writing my own memory manager, I am thinking to use dpdk rte_malloc or rte_mempool. Please let me know if this is a good idea.
>
> Also,
>
> my_node_t *data_ptr = (my_node_t *) (uintptr_t) rte_malloc(NULL, sizeof(my_node_t), 0);
>
> data_ptr is pointing to some invalid memory.  Am I doing anything wrong here?
>
>
> Thanks,
> Rohit

Re: Use rte_malloc in application

[Stefan Puiu]

Hi,

This is not strictly DPDK-related, but still...

On Thu, Aug 3, 2017 at 9:12 AM, Rohit Saini (Stellus)
<rohit.saini@stellus.com> wrote:
> With below code, I am getting this warning.
>
> warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
>
> my_node_t *data_ptr = (my_node_t *) rte_malloc(NULL, sizeof(my_node_t), 0);

I think the warning concerns the first argument passed to rte_malloc.
NULL probably expands to 0 (at least that seems to happen in C++), so
it gets treated as an int instead of a pointer. In C++11, there's
nullptr for this; or you could simply use a non-NULL string.

HTH,
Stefan.

>
> Thanks,
> Rohit
>
> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Rohit Saini (Stellus)
> Sent: Thursday, August 03, 2017 11:28 AM
> To: 'dev@dpdk.org' <dev@dpdk.org>
> Subject: [dpdk-dev] Use rte_malloc in application
>
> Hi,
> I have a use case in my application where I need to implement my own memory manager, rather than doing malloc/free everytime to kernel.
> Instead of writing my own memory manager, I am thinking to use dpdk rte_malloc or rte_mempool. Please let me know if this is a good idea.
>
> Also,
>
> my_node_t *data_ptr = (my_node_t *) (uintptr_t) rte_malloc(NULL, sizeof(my_node_t), 0);
>
> data_ptr is pointing to some invalid memory.  Am I doing anything wrong here?
>
>
> Thanks,
> Rohit

Re: Use rte_malloc in application

[Rohit Saini (Stellus)]

Thanks Sergio. It helped. There was a mistake the way I was linking dpdk with my application.

Thanks,
Rohit

-----Original Message-----
From: Sergio Gonzalez Monroy [mailto:sergio.gonzalez.monroy@intel.com] 
Sent: Thursday, August 03, 2017 1:59 PM
To: Rohit Saini (Stellus) <rohit.saini@stellus.com>; 'dev@dpdk.org' <dev@dpdk.org>
Subject: Re: [dpdk-dev] Use rte_malloc in application

On 03/08/2017 07:12, Rohit Saini (Stellus) wrote:
> With below code, I am getting this warning.
>
> warning: cast to pointer from integer of different size 
> [-Wint-to-pointer-cast]
>
> my_node_t *data_ptr = (my_node_t *) rte_malloc(NULL, 
> sizeof(my_node_t), 0);

As far as I can see, the syntax looks correct.

How are you building/linking your application?

I would suggest to modify the DPDK examples/helloworld application to just do a simple rte_malloc as a first step.

Thanks,
Sergio


> Thanks,
> Rohit
>
> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Rohit Saini 
> (Stellus)
> Sent: Thursday, August 03, 2017 11:28 AM
> To: 'dev@dpdk.org' <dev@dpdk.org>
> Subject: [dpdk-dev] Use rte_malloc in application
>
> Hi,
> I have a use case in my application where I need to implement my own memory manager, rather than doing malloc/free everytime to kernel.
> Instead of writing my own memory manager, I am thinking to use dpdk rte_malloc or rte_mempool. Please let me know if this is a good idea.
>
> Also,
>
> my_node_t *data_ptr = (my_node_t *) (uintptr_t) rte_malloc(NULL, 
> sizeof(my_node_t), 0);
>
> data_ptr is pointing to some invalid memory.  Am I doing anything wrong here?
>
>
> Thanks,
> Rohit