Re: [RFC 4/5] x86, perf: implements lwp-perf-integration (rc1)

From: Robert Richter
Date: Mon Dec 19 2011 - 04:09:33 EST


On 19.12.11 00:43:10, Ingo Molnar wrote:
> So the question becomes, how well is it integrated: can
> perf 'record -a + perf report', or 'perf top' use LWP,
> to do system-wide precise [user-space] profiling and such?

There is only self-monitoring of a process possible, no kernel and
system-wide profiling. This is because we can not allocate memory
regions in the kernel for a thread other than the current. This would
require a complete rework of mm code.

-Robert

--
Advanced Micro Devices, Inc.
Operating System Research Center

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