Re: [PATCH 5/9] perf, tools: Compute IPC and basic block cycles for annotate

From	Andi Kleen <andi@firstfloor.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH 5/9] perf, tools: Compute IPC and basic block cycles for annotate
Date	2016-07-02 22:40 +0200
Message-ID	<rQzRL-8a7-3@gated-at.bofh.it> (permalink)
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> I'm looking at basic block support, but this all seems to depend on the
> cycles stuff. Can we get the basic block stuff without that?

Not sure what you mean with basic block stuff, but ...
> 
> I'm looking to plot the hottest path through a branchy function.

Use --branch-history to get a histogram of the hottest paths.
If you want a longer history than 16/32 you can also use PT
and tell the decoder to synthesize larger LBRs.

However currently it cannot output metadata like cycles

Or apply the following patches to show the path with perf script for
individual samples
(unfortunatly the disassembler support was rejected, so this
won't be available in mainline)

https://git.kernel.org/cgit/linux/kernel/git/ak/linux-misc.git/log/?h=perf/disassembler-1

-Andi

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Re: [PATCH 5/9] perf, tools: Compute IPC and basic block cycles for  annotate Peter Zijlstra <peterz@infradead.org> - 2016-06-30 11:50 +0200
  Re: [PATCH 5/9] perf, tools: Compute IPC and basic block cycles for  annotate Andi Kleen <andi@firstfloor.org> - 2016-07-02 22:40 +0200

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