Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210723011436.60960-1-surenb@google.com> <CALvZod7ehaHoWRD-Pzvet5c1LQ6DYDHjs=xbJWZYEdMsgTpRgA@mail.gmail.com>
 <CAJuCfpFZeQez77CB7odfaSpi3JcLQ_Nz0WvDTsra1VPoA-j7sg@mail.gmail.com>
 <YPpfo2z8feq0vTlE@dhcp22.suse.cz> <CAJuCfpGSZwVgZ=FxhCV-uC_mzC7O-v-3k3tm-F6kOB7WM9t9tw@mail.gmail.com>
 <YPqDnqULylkkzQG5@dhcp22.suse.cz>
In-Reply-To: <YPqDnqULylkkzQG5@dhcp22.suse.cz>
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>,
        Johannes Weiner <hannes@cmpxchg.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>,
        David Hildenbrand <david@redhat.com>,
        Jann Horn <jannh@google.com>,
        Andy Lutomirski <luto@kernel.org>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Florian Weimer <fweimer@redhat.com>,
        Jan Engelhardt <jengelh@inai.de>,
        Tim Murray <timmurray@google.com>,
        Linux API <linux-api@vger.kernel.org>,
        Linux MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        kernel-team <kernel-team@android.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

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.