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From:   Daniel Colascione <dancol@google.com>
Date:   Thu, 5 Sep 2019 15:51:19 -0700
Message-ID: <CAKOZuetLW31vrsxndrH7gVh5er+J5DepBY6XcfxnFmZQaLWhrQ@mail.gmail.com>
Subject: Re: [PATCH v2] mm: emit tracepoint when RSS changes by threshold
To:     Tom Zanussi <zanussi@kernel.org>
Cc:     Joel Fernandes <joel@joelfernandes.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Michal Hocko <mhocko@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Tim Murray <timmurray@google.com>,
        Carmen Jackson <carmenjackson@google.com>,
        Mayank Gupta <mayankgupta@google.com>,
        Minchan Kim <minchan@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        kernel-team <kernel-team@android.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Jerome Glisse <jglisse@redhat.com>,
        linux-mm <linux-mm@kvack.org>,
        Matthew Wilcox <willy@infradead.org>,
        Ralph Campbell <rcampbell@nvidia.com>,
        Vlastimil Babka <vbabka@suse.cz>
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On Thu, Sep 5, 2019 at 3:12 PM Daniel Colascione <dancol@google.com> wrote:
> Basically, what I have in mind is this:

Actually --- I wonder whether there's already enough power in the
trigger mechanism to do this without any code changes to ftrace
histograms themselves. I'm trying to think of the minimum additional
kernel facility that we'd need to implement the scheme I described
above, and it might be that we don't need to do anything at all except
add the actual level tracepoints.