Re: [PATCH 1/1] mm/page_owner: store page_owner's gfp_mask in stackdepot itself

[Vlastimil Babka]

On 6/7/19 7:53 AM, Sai Charan Sane wrote:
> Memory overhead of 4MB is reduced by storing gfp_mask in stackdepot along
> with stacktrace. Stackdepot memory usage increased by ~100kb for 4GB of RAM.
> 
> Page owner logs from dmesg:
> 	Before patch:
> 		allocated 20971520 bytes of page_ext
> 	After patch:
> 		allocated 16777216 bytes of page_ext
> 
> Signed-off-by: Sai Charan Sane <s.charan@xxxxxxxxxxx>

I don't know, this looks like unneeded abuse to me. In the debug
scenario when someone boots a kernel with page_owner enabled, does 4MB
out of 4GB RAM really make a difference?