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To: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andi Kleen <andi@firstfloor.org>, Ingo Molnar <mingo@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Tom Zanussi <tom.zanussi@linux.intel.com>,
        Jovi Zhangwei <jovi.zhangwei@gmail.com>,
        Eric Dumazet <edumazet@google.com>, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH tip 0/5] tracing filters with BPF
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From: fche@redhat.com (Frank Ch. Eigler)
Date: Thu, 05 Dec 2013 11:11:57 -0500
In-Reply-To: <CAMEtUuzWLcTOeQSrhEQHVn7DbuoJn7bNek9-toQ9xZYzya3-ag@mail.gmail.com> (Alexei Starovoitov's message of "Wed, 4 Dec 2013 20:40:44 -0800")
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ast wrote:

>>[...]
> Did simple ktap test with 1M alloc_skb/kfree_skb toy test from earlier email:
> trace skb:kfree_skb {
>         if (arg2 == 0x100) {
>                 printf("%x %x\n", arg1, arg2)
>         }
> }
> [...]

For reference, you might try putting systemtap into the performance
comparison matrix too:

# stap -e 'probe kernel.trace("kfree_skb") { 
              if ($location == 0x100 /* || $location == 0x200 etc. */ ) {
                 printf("%x %x\n", $skb, $location)
              }
           }'


- FChE