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Date:   Wed, 7 Jul 2021 14:38:40 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     Christian Brauner <christian.brauner@ubuntu.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Andy Lutomirski <luto@kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        David Rientjes <rientjes@google.com>,
        Matthew Wilcox <willy@infradead.org>,
        Roman Gushchin <guro@fb.com>, Rik van Riel <riel@surriel.com>,
        Minchan Kim <minchan@kernel.org>,
        Christian Brauner <christian@brauner.io>,
        Christoph Hellwig <hch@infradead.org>,
        Oleg Nesterov <oleg@redhat.com>, Jann Horn <jannh@google.com>,
        Shakeel Butt <shakeelb@google.com>,
        Tim Murray <timmurray@google.com>,
        Linux API <linux-api@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Android Kernel Team <kernel-team@android.com>
Subject: Re: [PATCH 1/1] mm: introduce process_reap system call
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On Mon 05-07-21 09:41:54, David Hildenbrand wrote:
> On 02.07.21 17:27, Christian Brauner wrote:
[...]
> > That one was my favorite from the list I gave too but maybe we can
> > satisfy Andy too if we use one of:
> > - process_mfree()
> > - process_mrelease()
> > 
> 
> FWIW, I tend to like process_mrelease(), due to the implied "release" ("free
> the memory if there are no other references") semantics.

Agreed.

> Further, a new
> syscall feels cleaner than some magic sysfs/procfs toggle. Just my 2 cents.

Yeah, proc based interface is both tricky to use and kinda ugly now that
pidfd can solve all at in once.

My original preference was a more generic kill syscall to allow flags
but a dedicated syscall doesn't look really bad either.
-- 
Michal Hocko
SUSE Labs