Re: [PATCH -tip perf/probes 00/10] x86 insn decoder bugfixes andperf-probe syntax changes

From: Masami Hiramatsu
Date: Mon Nov 02 2009 - 16:17:30 EST


Masami Hiramatsu wrote:
Ingo Molnar wrote:
What we want here is two fold:

- enable kprobes event support when perf events is enabled and kprobes
is enabled. We dont want another config option for it.

Sure, at least that combination should enable kprobe-tracer forcibly.

Hmm, someone may not want to enables kprobe-tracer. Perhaps,
"default y if (EVENT_PROFILE)" is enough, isn't it?


A few further (and very small) UI tweaks i'd suggest:

Firstly, could we please make the first probe inserted named plain after
the symbol it specifies, with no _0 postfix? I.e. instead of:

7358 perfprobe:__switch_to_0 # 0.000 M/sec

we'd get:

7358 perfprobe:__switch_to # 0.000 M/sec

Subsequent probes for the same symbol can be named _1, _2 - but the
first symbol should not have this needless post-fix.

Ah, this prefix means the offset from the symbol. Of course we can
remove it if the offset == 0. Or, would you think make the postfix
sequence number of probes on the same symbol?

If so, we'd better have --list option before that and check the
postfix is already used, since we may not want to overwrite
existing probes, right?

Thank you,

--
Masami Hiramatsu

Software Engineer
Hitachi Computer Products (America), Inc.
Software Solutions Division

e-mail: mhiramat@xxxxxxxxxx

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/