Re: [PATCH] Doc fix for dget_dlock

From: Randy Dunlap
Date: Thu Aug 11 2022 - 14:35:18 EST




On 8/11/22 11:33, Randy Dunlap wrote:
> Hi--
>
> On 8/11/22 07:48, Anup Parikh wrote:
>> Hello Mr. Randy Dunlap,
>>
>> I checked include/linux/dcache.h (dget() and dget_dlock()), include/linux/lockref.h and linux/lib/lockref.c.
>> My current knowledge is limited but I think:
>> 1) dget_dlock() directly increments the count variable without any atomicity guards.
>> 2) dget() does the same but with atomicity guarantee - even across multiple-cores on a multi-core system (according to https://stackoverflow.com/questions/36964478/understanding-synchronization-with-multiple-processors <https://stackoverflow.com/questions/36964478/understanding-synchronization-with-multiple-processors> and code in linux/lib/lockref.c).
>>
>> Please let me know if I should write the corresponding documentation and send a new patch.
>
> Yes, please.
> Thanks.

also send the patch to linux-fsdevel@xxxxxxxxxxxxxxx
since it touches filesystem code.

>
>> Thanks and Regards,
>> Anup K Parikh.
>>
>>
>> On Tue, Aug 9, 2022 at 11:58 PM Randy Dunlap <rdunlap@xxxxxxxxxxxxx <mailto:rdunlap@xxxxxxxxxxxxx>> wrote:
>>
>> Hi--
>>
>> On 8/5/22 09:39, Anup K Parikh wrote:
>> > Removes the warning for dget_dlock in include/linux/dcache.h and
>> > enables generation of its API documentation
>> >
>> > Signed-off-by: Anup K Parikh <parikhanupk.foss@xxxxxxxxx <mailto:parikhanupk.foss@xxxxxxxxx>>
>> > ---
>> >  include/linux/dcache.h | 2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> >
>> > diff --git a/include/linux/dcache.h b/include/linux/dcache.h
>> > index f5bba5148..ce0b36f72 100644
>> > --- a/include/linux/dcache.h
>> > +++ b/include/linux/dcache.h
>> > @@ -297,7 +297,7 @@ extern char *dentry_path(const struct dentry *, char *, int);
>> >  /* Allocation counts.. */
>> > 
>> >  /**
>> > - *   dget, dget_dlock -      get a reference to a dentry
>> > + *   dget_dlock -    get a reference to a dentry
>> >   *   @dentry: dentry to get a reference to
>> >   *
>> >   *   Given a dentry or %NULL pointer increment the reference count
>>
>> Someone was trying to document both dget() and get_dlock() with the same
>> kernel-doc comment block.
>> I suppose that you could duplicate the comments for dget() also.
>>
>> It would be nice to know the difference(s) in the functions as well.
>>
>> thanks.
>> --
>> ~Randy
>>
>

--
~Randy