Re: [PATCH v1 03/19] split-index: add {add,remove}_split_index() functions

[Christian Couder <christian.couder@gmail.com>]

On Wed, Nov 9, 2016 at 10:24 AM, Duy Nguyen <pclouds@gmail.com> wrote:
> On Mon, Nov 7, 2016 at 5:08 PM, Duy Nguyen <pclouds@gmail.com> wrote:
>> On Sun, Oct 30, 2016 at 5:06 AM, Christian Couder
>> <christian.couder@gmail.com> wrote:
>>> On Tue, Oct 25, 2016 at 11:58 AM, Duy Nguyen <pclouds@gmail.com> wrote:
>>>> On Sun, Oct 23, 2016 at 4:26 PM, Christian Couder
>>>> <christian.couder@gmail.com> wrote:
>>>>> +void remove_split_index(struct index_state *istate)
>>>>> +{
>>>>> +       if (istate->split_index) {
>>>>> +               /*
>>>>> +                * can't discard_split_index(&the_index); because that
>>>>> +                * will destroy split_index->base->cache[], which may
>>>>> +                * be shared with the_index.cache[]. So yeah we're
>>>>> +                * leaking a bit here.
>>>>
>>>> In the context of update-index, this is a one-time thing and leaking
>>>> is tolerable. But because it becomes a library function now, this leak
>>>> can become more serious, I think.
>>>>
>>>> The only other (indirect) caller is read_index_from() so probably not
>>>> bad most of the time (we read at the beginning of a command only).
>>>> sequencer.c may discard and re-read the index many times though,
>>>> leaking could be visible there.
>>>
>>> So is it enough to check if split_index->base->cache[] is shared with
>>> the_index.cache[] and then decide if discard_split_index(&the_index)
>>> should be called?
>>
>> It's likely shared though. We could un-share cache[] by duplicating
>> index entries in the_index.cache[] if they point back to
>> split_index->base
>
> I have a patch for this. So don't have to do anything else in this
> area. I'll probably just pile my patch on top of your series, or post
> it once the series graduates to master.

Great, thanks!