On Tue, Jun 26, 2018 at 11:00:53AM -0700, Shakeel Butt wrote:

On Mon, Jun 25, 2018 at 10:49 PM Amir Goldstein [off-list ref] wrote:

quoted

...

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The verb 'unuse' takes an argument memcg and 'uses' it - too weird.
You can use 'override'/'revert' verbs like override_creds or just call
memalloc_use_memcg(old_memcg) since there is no reference taken
anyway in use_memcg and no reference released in unuse_memcg.

Otherwise looks good to me.

Thanks for your feedback. Just using memalloc_use_memcg(old_memcg) and
ignoring the return seems more simple. I will wait for feedback from
other before changing anything.

We're not nesting calls to memalloc_use_memcg(), right? So we don't
have to return old_memcg and don't have to pass anything to unuse, it
can always set current->active_memcg to NULL.