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From:   Shakeel Butt <shakeelb@google.com>
Date:   Fri, 23 Jul 2021 06:46:06 -0700
Message-ID: <CALvZod4=9aEd9tUdku293uhVQ4mqsfYckCOKzqxXVTDYsmaVtQ@mail.gmail.com>
Subject: Re: [PATCH v3 1/2] mm: introduce process_mrelease system call
To:     Michal Hocko <mhocko@suse.com>
Cc:     Suren Baghdasaryan <surenb@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        David Rientjes <rientjes@google.com>,
        Matthew Wilcox <willy@infradead.org>,
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        Linux API <linux-api@vger.kernel.org>,
        Linux MM <linux-mm@kvack.org>,
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On Fri, Jul 23, 2021 at 1:53 AM Michal Hocko <mhocko@suse.com> wrote:
>
[...]
> > However
> > retrying means issuing another syscall, so additional overhead...
> > I guess such "best effort" approach would be unusual for a syscall, so
> > maybe we can keep it as it is now and if such "do not block" mode is needed
> > we can use flags to implement it later?
>
> Yeah, an explicit opt-in via flags would be an option if that turns out
> to be really necessary.
>

I am fine with keeping it as it is but we do need the non-blocking
option (via flags) to enable userspace to act more aggressively.