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From:   Tri Vo <trong@android.com>
Date:   Wed, 26 Jun 2019 15:48:58 -0700
Message-ID: <CANA+-vD+qBqENZrk_7KZzedbzGPMzHniHTE4sY93gnkzzBif6A@mail.gmail.com>
Subject: Re: [PATCH] PM / wakeup: show wakeup sources stats in sysfs
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Hridya Valsaraju <hridya@google.com>,
        Sandeep Patil <sspatil@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux PM <linux-pm@vger.kernel.org>,
        "Cc: Android Kernel" <kernel-team@android.com>
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On Tue, Jun 25, 2019 at 6:33 PM Tri Vo <trong@android.com> wrote:
>
> On Tue, Jun 25, 2019 at 6:12 PM Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > On Tue, Jun 25, 2019 at 05:54:49PM -0700, Tri Vo wrote:
> > > Embedding a struct kobject into struct wakeup_source changes lifetime
> > > requirements on the latter. To that end, change deallocation of struct
> > > wakeup_source using kfree to kobject_put().
> >
> > Ick, are you sure you need a new kobject here?  Why wouldn't a named
> > attribute group work instead?  That should keep this patch much smaller
> > and simpler.
>
> Yeah, named attribute groups might be a much cleaner way to do this.
> Let me investigate.

Say, we read /sys/power/wakeup_sources/foo/active_count. This
attribute's show function needs to find wakeup_source struct of "foo".
I'm not sure how to do that without embedding a kobject inside of
wakeup_source.