Date: Fri, 25 Apr 2014 10:20:56 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: linux-kernel@vger.kernel.org, Andi Kleen <andi@firstfloor.org>,
        Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
        Sandeepa Prabhu <sandeepa.prabhu@linaro.org>,
        Frederic Weisbecker <fweisbec@gmail.com>, x86@kernel.org,
        Steven Rostedt <rostedt@goodmis.org>, fche@redhat.com,
        mingo@redhat.com, systemtap@sourceware.org,
        "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH -tip v9 25/26] kprobes: Introduce kprobe cache to reduce
 cache misshits
Message-ID: <20140425082056.GB24829@gmail.com>
References: <20140417081636.26341.87858.stgit@ltc230.yrl.intra.hitachi.co.jp>
 <20140417081931.26341.47154.stgit@ltc230.yrl.intra.hitachi.co.jp>
 <20140424090134.GC7768@gmail.com>
 <5358F7A3.1000108@hitachi.com>
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* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> wrote:

> > So I don't think this should be a Kconfig entry, just enable it 
> > unconditionally. That will further simplify the code.
> 
> Hmm, it consumes some amount of memory (36KB/core) just for the case 
> of several thousand of kprobes. On enterprise servers and desktop 
> it's OK, no problem. But I think, some embedded systems with small 
> resources will not want that. [...]

They'll just disable kprobes in general.

Really, at this point complexity is our main concern.

Thanks,

	Ingo
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