[Devel] Re: [PATCH v5 04/18] slab: don't preemptively remove element from list in cache destroy

[Pekka Enberg]

On Mon, Oct 22, 2012 at 11:40 AM, Glauber Costa <glommer at parallels.com> wrote:
> On 10/19/2012 11:34 PM, Christoph Lameter wrote:
>> On Fri, 19 Oct 2012, Glauber Costa wrote:
>>
>>> I, however, see no reason why we need to do so, since we are now locked
>>> during the whole deletion (which wasn't necessarily true before).  I
>>> propose a simplification in which we delete it only when there is no
>>> more going back, so we don't need to add it again.
>>
>> Ok lets hope that holding the lock does not cause issues.
>>
>> Acked-by: Christoph Lameter <cl at linux.com>
>>
> BTW: One of the good things about this set, is that we are naturally
> exercising cache destruction a lot more than we did before. So if there
> is any problem, either with this or anything related to cache
> destruction, it should at least show up a lot more frequently. So far,
> this does not seem to cause any problems.

We no longer hold the mutex the whole time after. See commit 210ed9d
("mm, slab: release slab_mutex earlier in kmem_cache_destroy()") for
details.