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Subject: Re: [External] Re: [PATCH v15 4/8] mm: hugetlb: alloc the vmemmap
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To:     Michal Hocko <mhocko@suse.com>
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From:   Mike Kravetz <mike.kravetz@oracle.com>
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On 2/17/21 12:13 AM, Michal Hocko wrote:
> On Tue 16-02-21 11:44:34, Mike Kravetz wrote:
> [...]
>> If we are not going to do the allocations under the lock, then we will need
>> to either preallocate or take the workqueue approach.
> 
> We can still drop the lock temporarily right? As we already do before
> calling destroy_compound_gigantic_page...
> 

Yes we can.  I forgot about that.

Actually, very little of what update_and_free_page does needs to be done
under the lock.  Perhaps, just decrementing the global count and clearing
the destructor so PageHuge() is no longer true.
-- 
Mike Kravetz