Re: PATCH: two slab-like memory allocators

On 10/1/16 7:34 PM, Tomas Vondra wrote:
>> + /* otherwise add it to the proper freelist bin */
>> Looks like something went missing... :)
>>
>
> Ummm? The patch contains this:
>
> + /* otherwise add it to the proper freelist bin */
> + if (set->freelist[block->nfree])
> + set->freelist[block->nfree]->prev = block;
> +
> + block->next = set->freelist[block->nfree];
> + set->freelist[block->nfree] = block;
>
> Which does exactly the thing it should do. Or what is missing?

What's confusing is the "otherwise" right at the beginning of the function:

+static void
+add_to_freelist(Slab set, SlabBlock block)
+{
+ /* otherwise add it to the proper freelist bin */
+ if (set->freelist[block->nfree])
+ set->freelist[block->nfree]->prev = block;
+
+ block->next = set->freelist[block->nfree];
+ set->freelist[block->nfree] = block;
+}

Otherwise what? What's the other option?

(Haven't looked at the newer patch, so maybe this isn't an issue anymore.)
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