Re: [PATCH 1/3] lockdep: Apply crossrelease to PG_locked locks

From: Byungchul Park
Date: Thu Nov 16 2017 - 07:48:20 EST

On 11/16/2017 9:02 PM, Michal Hocko wrote:
for each struct page. So you are doubling the size. Who is going to
enable this config option? You are moving this to page_ext in a later
patch which is a good step but it doesn't go far enough because this
still consumes those resources. Is there any problem to make this
kernel command line controllable? Something we do for page_owner for

Sure. I will add it.

Also it would be really great if you could give us some measures about
the runtime overhead. I do not expect it to be very large but this is

The major overhead would come from the amount of additional memory
consumption for 'lockdep_map's.

Do you want me to measure the overhead by the additional memory

Or do you expect another overhead?

Could you tell me what kind of result you want to get?

something people are usually interested in when enabling debugging