Re: [PATCH 1/2] rcu: introduce list_last_or_null_rcu

[Dan Streetman]

On Thu, May 28, 2015 at 5:17 PM, Paul E. McKenney
<paulmck@xxxxxxxxxxxxxxxxxx> wrote:
> On Thu, May 28, 2015 at 05:14:25PM -0400, Dan Streetman wrote:
>> On Thu, May 28, 2015 at 5:05 PM, Paul E. McKenney
>> <paulmck@xxxxxxxxxxxxxxxxxx> wrote:
>> > On Thu, May 28, 2015 at 04:42:20PM -0400, Dan Streetman wrote:
>> >> On Thu, May 28, 2015 at 4:39 PM,  <josh@xxxxxxxxxxxxxxxx> wrote:
>> >> > On Thu, May 28, 2015 at 04:35:27PM -0400, Dan Streetman wrote:
>> >> >> Add list_last_or_null_rcu(), to simplify getting the last entry from a
>> >> >> rcu-protected list.  The standard list_last_entry() can't be used as it
>> >> >> is not rcu-protected; the list may be modified concurrently.  And the
>> >> >> ->prev pointer can't be used, as only the ->next pointers are protected
>> >> >> by rcu.
>> >> >>
>> >> >> This simply iterates forward through the entire list, to get to the last
>> >> >> entry.  If the list is empty, it returns NULL.
>> >> >>
>> >> >> Signed-off-by: Dan Streetman <ddstreet@xxxxxxxx>
>> >> >
>> >> > The list iteration functions are macros because they introduce a loop
>> >> > with attached loop block.  For this, is there any reason not to make it
>> >> > an inline function instead of a macro?
>> >>
>> >> true, there's no reason i can see not to make it inline, let me send
>> >> an updated patch.
>> >
>> > Hmmm...  If we can now do type-generic inline functions, it might make
>> > sense to convert some of the others as well.
>>
>> oh, ok.  how do we do type-generic inline funcs?  return void*?
>
> I was hoping that you would tell me.  I use macros in that case.

ha, if I ever get to the point where i think i know more than you,
i'll let you know ;-)

>
>                                                         Thanx, Paul
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/