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Re: [PATCH -tip v9 25/26] kprobes: Introduce kprobe cache to reduce cache misshits
- From: Ingo Molnar <mingo at kernel dot org>
- To: Masami Hiramatsu <masami dot hiramatsu dot pt at hitachi dot com>
- Cc: linux-kernel at vger dot kernel dot org, Andi Kleen <andi at firstfloor dot org>, Ananth N Mavinakayanahalli <ananth at in dot ibm dot com>, Sandeepa Prabhu <sandeepa dot prabhu at linaro dot org>, Frederic Weisbecker <fweisbec at gmail dot com>, x86 at kernel dot org, Steven Rostedt <rostedt at goodmis dot org>, fche at redhat dot com, mingo at redhat dot com, systemtap at sourceware dot org, "H. Peter Anvin" <hpa at zytor dot com>, Thomas Gleixner <tglx at linutronix dot de>
- Date: Fri, 25 Apr 2014 10:20:56 +0200
- Subject: Re: [PATCH -tip v9 25/26] kprobes: Introduce kprobe cache to reduce cache misshits
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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