Concurrency in JFFS2?

[Martin Galvan]

I see, thanks for your answer. What about the eCos mutexes though? You
mentioned eCos having a global lock for the filesystem, yet I saw more
fine-grained locked in e.g. jffs2_new_inode.

On Fri, Dec 4, 2015 at 3:36 AM, Sebastian Huber
<sebastian.huber at embedded-brains.de> wrote:
> See
>
> struct _rtems_filesystem_operations_table {
>   rtems_filesystem_mt_entry_lock_t lock_h;
>   rtems_filesystem_mt_entry_unlock_t unlock_h;
> ...
> };
>
>
> On 03/12/15 15:30, Martin Galvan wrote:
>>
>> Oh, I see. Do you happen to remember where that lock is
>> acquired/released? I saw the up/down macros in the eCos code at the
>> points where the RTEMS mutex_lock/unlock would be called (e.g. in
>> jffs2_new_inode). up/down end up calling Cyg_Mutex::unlock/lock, which
>> aren't empty, so it seems that there's a bit of fine-grained locking
>> there.
>>
>> On Thu, Dec 3, 2015 at 3:19 AM, Sebastian Huber
>> <sebastian.huber at embedded-brains.de> wrote:
>>>
>>> Hello,
>>>
>>> I used the eCos port of JFFS2 as a base for the RTEMS port. Like in eCos,
>>> a global lock for a JFFS2 file system instance is used.
>>>
>>> ----- Martin Galvan <martin.galvan at tallertechnologies.com> schrieb:
>>>>
>>>> Hi everyone! I'm working on porting F2FS from Linux based on the JFFS2
>>>> port Sebastian did. When inspecting the code I found that
>>>> libfs/jffs2/include/linux/mutex defines struct mutex to be empty, and
>>>> all the mutex-related functions to do nothing.
>>>>
>>>> This seems to imply that there's no concurrency management in the
>>>> JFFS2 code. Is this intentional? Should I do the same when porting
>>>> F2FS?
>>>
>>> --
>>> Sebastian Huber, embedded brains GmbH
>>>
>>> Address : Dornierstr. 4, D-82178 Puchheim, Germany
>>> Phone   : +49 89 189 47 41-16
>>> Fax     : +49 89 189 47 41-09
>>> E-Mail  : sebastian.huber at embedded-brains.de
>>> PGP     : Public key available on request.
>>>
>>> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
>>
>>
>>
>
> --
> Sebastian Huber, embedded brains GmbH
>
> Address : Dornierstr. 4, D-82178 Puchheim, Germany
> Phone   : +49 89 189 47 41-16
> Fax     : +49 89 189 47 41-09
> E-Mail  : sebastian.huber at embedded-brains.de
>
> PGP     : Public key available on request.
>
> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
>



-- 


Martin Galvan

Software Engineer

Taller Technologies Argentina


San Lorenzo 47, 3rd Floor, Office 5

Córdoba, Argentina

Phone: 54 351 4217888 / +54 351 4218211