lkml.org 
[lkml]   [2016]   [Jul]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subjectwhy not add __GFP_HIGHMEM directly in alloc_migrate_target()?
alloc_migrate_target() is called from migrate_pages(),
so the page is always from user space, so why not add
__GFP_HIGHMEM directly, instead of the following code.

if (PageHighMem(page)) // it always return false in x86_64
gfp_mask |= __GFP_HIGHMEM;


Another question, when we do migration, why should split THP
first?
e.g. 2M(512*4kb) should flush 512 times TLB, and 2M(2M*1) only need one.
I find flush TLB takes a lot of time, especially multithreaded app.

Thanks,
Xishi Qiu

\
 
 \ /
  Last update: 2016-07-12 16:21    [W:0.100 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site