Re: [PATCH 05/11] android: ram_console: split out persistent ram

Colin Cross
2012-03-08T18:24:15Z

On Thu, Mar 8, 2012 at 9:33 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Wed, Mar 07, 2012 at 07:06:42PM -0800, Colin Cross wrote:
>> On Wed, Mar 7, 2012 at 6:42 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
>> > On Wed, Mar 07, 2012 at 05:34:32PM -0800, John Stultz wrote:
>> >> From: Colin Cross <ccross@android.com>
>> >>
>> >> Split ram_console into two halves.
>> >>
>> >> persistent_ram is a set of apis that handle a block of memory
>> >> that does not get erased across a reboot.  It provides functions
>> >> to fill it as a single buffer or a ring buffer, and to extract
>> >> the old data after a reboot.  It handles ecc on the data to
>> >> correct bit errors introduced during reboot.
>> >
>> > That's a nice idea, but why are you rolling your own interface here and
>> > not using the built-in one that the kernel already provides?  Is there
>> > something lacking with what we have today that requires you to create
>> > something different?  If so, why not just modify the existing interface
>> > to make it work for you, that way the tools already created will work
>> > automatically, and you will not have problems later ripping this out and
>> > porting it to the in-kernel api.
>>
>> What interface are you referring to, pstore?
>
> Yes.
>
>> As I explained in the email John quoted to you,
>
> Wait, what email?  Did I miss a response here?  Have a message-id: I can
> search for?

Message ID 1331160054.2191.202.camel@work-vm

>> pstore would be a client of this, and ramconsole could be moved on top
>> of pstore.
>
> Ok, as long as that is the end goal, that's fine, it was not obvious
> that this was the case at all, hence my confusion.
>
>> This patch is just a refactoring that splits ramconsole and the
>> persistent storage apart without significantly changing the api
>> between them, and only makes it easier to insert pstore between them.
>
> That's good to hear, I'll go queue them up then, thanks for clearing
> this up.
>
> greg k-h