Re: [PATCH v2 5/5] mm/hugetlb: avoid calculating fault_mutex_hash in truncate_op case

2021-03-16 Thread Miaohe Lin
On 2021/3/17 8:27, Mike Kravetz wrote: > On 3/15/21 11:49 PM, Miaohe Lin wrote: >> On 2021/3/16 11:07, Mike Kravetz wrote: >>> On 3/15/21 7:27 PM, Miaohe Lin wrote: The fault_mutex hashing overhead can be avoided in truncate_op case because page faults can not race with truncation in

Re: [PATCH v2 5/5] mm/hugetlb: avoid calculating fault_mutex_hash in truncate_op case

2021-03-16 Thread Mike Kravetz
On 3/15/21 11:49 PM, Miaohe Lin wrote: > On 2021/3/16 11:07, Mike Kravetz wrote: >> On 3/15/21 7:27 PM, Miaohe Lin wrote: >>> The fault_mutex hashing overhead can be avoided in truncate_op case >>> because page faults can not race with truncation in this routine. So >>> calculate hash for

Re: [PATCH v2 5/5] mm/hugetlb: avoid calculating fault_mutex_hash in truncate_op case

2021-03-16 Thread Miaohe Lin
On 2021/3/16 11:07, Mike Kravetz wrote: > On 3/15/21 7:27 PM, Miaohe Lin wrote: >> The fault_mutex hashing overhead can be avoided in truncate_op case >> because page faults can not race with truncation in this routine. So >> calculate hash for fault_mutex only in !truncate_op case to save some

Re: [PATCH v2 5/5] mm/hugetlb: avoid calculating fault_mutex_hash in truncate_op case

2021-03-15 Thread Mike Kravetz
On 3/15/21 7:27 PM, Miaohe Lin wrote: > The fault_mutex hashing overhead can be avoided in truncate_op case > because page faults can not race with truncation in this routine. So > calculate hash for fault_mutex only in !truncate_op case to save some cpu > cycles. > > Reviewed-by: Mike Kravetz