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Date:   Thu, 14 Mar 2019 20:45:02 -0700
From:   Sultan Alsawaf <sultan@kerneltoast.com>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Joel Fernandes <joel@joelfernandes.org>,
        Tim Murray <timmurray@google.com>,
        Michal Hocko <mhocko@kernel.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arve =?iso-8859-1?B?SGr4bm5lduVn?= <arve@android.com>,
        Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
        Christian Brauner <christian@brauner.io>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "open list:ANDROID DRIVERS" <devel@driverdev.osuosl.org>,
        linux-mm <linux-mm@kvack.org>,
        kernel-team <kernel-team@android.com>
Subject: Re: [RFC] simple_lmk: Introduce Simple Low Memory Killer for Android
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On Thu, Mar 14, 2019 at 11:16:41PM -0400, Steven Rostedt wrote:
> How would you implement such a method in userspace? kill() doesn't take
> any parameters but the pid of the process you want to send a signal to,
> and the signal to send. This would require a new system call, and be
> quite a bit of work. If you can solve this with an ebpf program, I
> strongly suggest you do that instead.

This can be done by introducing a new signal number that provides SIGKILL
functionality while blocking (maybe SIGKILLBLOCK?).

Thanks,
Sultan