Re: [PATCH v3] ARM: omap: edma: add suspend suspend/resume hooks

[Joel Fernandes <joelf@ti.com>]

On 10/09/2013 01:18 AM, Gururaja Hebbar wrote:
> On Wednesday 09 October 2013 11:33 AM, Fernandes, Joel wrote:
>> Some temporary issues with my mua so forgive any artifacts in this email.
>>
>> On Oct 9, 2013, at 12:14 AM, "Hebbar, Gururaja" <gururaja.hebbar@ti.com> wrote:
>>
>>> On Wednesday 09 October 2013 09:58 AM, Joel Fernandes wrote:
>>>> On 10/01/2013 10:04 AM, Daniel Mack wrote:
>>>>> This patch makes the edma driver resume correctly after suspend. Tested
>>>>> on an AM33xx platform with cyclic audio streams.
>>>>>
>>>>> The code was shamelessly taken from an ancient BSP tree.
>>>>>
>>>>> Signed-off-by: Daniel Mack <zonque@gmail.com>
>>>>> ---
>>>>> arch/arm/common/edma.c | 133 +++++++++++++++++++++++++++++++++++++++++++++++++
>>>>> 1 file changed, 133 insertions(+)
>>>
>>> ..snip..
>>> ..snip..
>>>>
>>>>> +        edma_cc[j]->context.ch_map =
>>>>> +            kzalloc((sizeof(unsigned int) *
>>>>> +                 edma_cc[j]->num_channels), GFP_KERNEL);
>>>>> +        edma_cc[j]->context.que_num =
>>>>> +            kzalloc((sizeof(unsigned int) * 8), GFP_KERNEL);
>>>>
>>>> Can these allocations be moved to the suspend path? For systems that don't
>>>> suspend/resume even once, I feel we shouldn't allocate memory that we don't use.
>>>> These allocations are better to do there.
>>>
>>> AFAIK, Suspend/resume should be quick. Allocating and deallocating on
>>> every iterating would be useless and time consuming.
>>
>> Nobody said allocate and deallocate on every iteration. Allocate once during the first suspend call and then don't have to allocate on subsequent calls.
> 
> I couldn't find any code which allocates parameters inside suspend.
> Could you show me some code which does this?

Based on my last reply to Daniel, inorder to restore- there's no need to
allocate/save anything.

thanks,

-Joel