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 fault_mutex only in !truncate_op case to save some cpu >>> cycles. >>> >>> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> >>> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> >>> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> >>> --- >>> v1->v2: >>> remove unnecessary initialization for variable hash >>> collect Reviewed-by tag from Mike Kravetz >> >> My apologies for not replying sooner and any misunderstanding from my >> previous comments. >> > > That's all right. > >> If the compiler is going to produce a warning because the variable is >> not initialized, then we will need to keep the initialization. >> Otherwise, this will show up as a build regression. Ideally, there >> would be a modifier which could be used to tell the compiler the >> variable will used. I do not know if such a modifier exists. >> > > I do not know if such a modifier exists too. But maybe not all compilers are intelligent > enough to not produce a warning. It would be safe to keep the initialization... > >> The patch can not produce a new warning. So, if you need to initialize > > So just drop this version of the patch? Or should I send a new version with your Reviewed-by tag and > keep the initialization? > Yes, drop this version of the patch. You can add my Reviewed-by to the previous version that included the initialization and resend. All the cleanup patches in this series should be good to go. -- Mike Kravetz
