Commit 0719fdba authored by Yixuan Cao's avatar Yixuan Cao Committed by Jonathan Corbet
Browse files

Documentation/mm/page_owner.rst: delete frequently changing experimental data 



The kernel size changes due to many factors, such as compiler
version, configuration, and the build environment. This makes
size comparison figures irrelevant to reader's setup.

Remove these figures and describe the effects of page owner
to the kernel size in general instead.

Thanks for Jonathan Corbet, Bagas Sanjaya and Mike Rapoport's
constructive suggestions.

Signed-off-by: default avatarYixuan Cao <caoyixuan2019@email.szu.edu.cn>
Link: https://lore.kernel.org/r/20221005145525.10359-1-caoyixuan2019@email.szu.edu.cn


Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent a0a6859f

Documentation/mm/page_owner.rst

+4 −16
Original line number Diff line number Diff line
@@ -38,22 +38,10 @@ not affect to allocation performance, especially if the static keys jump 
label patching functionality is available. Following is the kernel's code

size change due to this facility.



- Without page owner::



   text    data     bss     dec     hex filename

   48392   2333     644   51369    c8a9 mm/page_alloc.o



- With page owner::



   text    data     bss     dec     hex filename

   48800   2445     644   51889    cab1 mm/page_alloc.o

   6662     108      29    6799    1a8f mm/page_owner.o

   1025       8       8    1041     411 mm/page_ext.o



Although, roughly, 8 KB code is added in total, page_alloc.o increase by

520 bytes and less than half of it is in hotpath. Building the kernel with

page owner and turning it on if needed would be great option to debug

kernel memory problem.

Although enabling page owner increases kernel size by several kilobytes,

most of this code is outside page allocator and its hot path. Building

the kernel with page owner and turning it on if needed would be great

option to debug kernel memory problem.



There is one notice that is caused by implementation detail. page owner

stores information into the memory from struct page extension. This memory