From: Andi Kleen <andi@firstfloor.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <andi@firstfloor.org>,
Taylor Andrews <andrewst@vmware.com>,
"linux-perf-users@vger.kernel.org"
<linux-perf-users@vger.kernel.org>
Subject: Re: Question about Perf's handling of in-use performance counters
Date: Fri, 28 Oct 2016 08:40:12 -0700 [thread overview]
Message-ID: <20161028154012.GC26852@two.firstfloor.org> (raw)
In-Reply-To: <20161028140354.GH3142@twins.programming.kicks-ass.net>
> No, it was about the (mis)guide-line having fundamental races and the
> belief that the BIOS has no business what so ever using these resources
> to begin with.
In this case it's not the BIOS, but a hypervisor who allocates the
counter. I believe there are valid use cases here.
The same issue can also happen when people use user space perfmon
tools, like PCM or likwid, and potentially with other non BIOS users.
-Andi
next prev parent reply other threads:[~2016-10-28 15:40 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-10-21 21:59 Question about Perf's handling of in-use performance counters Taylor Andrews
2016-10-27 18:11 ` Andi Kleen
2016-10-27 21:00 ` Peter Zijlstra
2016-10-28 13:53 ` Andi Kleen
2016-10-28 14:03 ` Peter Zijlstra
2016-10-28 15:40 ` Andi Kleen [this message]
2016-10-28 16:28 ` Peter Zijlstra
2016-10-28 16:33 ` Andi Kleen
2016-10-28 18:28 ` Taylor Andrews
2016-11-30 15:44 ` Taylor Andrews
2016-11-30 18:17 ` Peter Zijlstra
2016-11-07 22:25 ` Taylor Andrews
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