linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@kernel.org>
To: Andi Kleen <andi@firstfloor.org>
Cc: linux-kernel@vger.kernel.org, eranian@google.com,
	Andi Kleen <ak@linux.intel.com>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Arnaldo Carvalho de Melo <acme@infradead.org>
Subject: Re: [PATCH 5/5] perf, x86: Move NMI clearing to end of PMI handler after the counter registers are reset
Date: Wed, 13 Feb 2013 10:10:22 +0100	[thread overview]
Message-ID: <20130213091022.GB7630@gmail.com> (raw)
In-Reply-To: <20130212151426.GA30577@one.firstfloor.org>


* Andi Kleen <andi@firstfloor.org> wrote:

> On Tue, Feb 12, 2013 at 09:43:46AM +0100, Ingo Molnar wrote:
> > Was this stress-tested on all affected main CPU types, or only 
> > on Haswell?
> 
> I tested it on Haswell and Ivy Bridge. I can also try Westmere 
> and a Saltwell(Atom), but for the majority of other family 6 
> systems I'll need to rely on the community.

The systems you tested should be OK.

> White listing is somewhat difficult because it affects the 
> architectural mode too.

Yeah, I'd rather avoid that.

> I don't really expect problems from this change, we should 
> probably have always done it like this.

I expect potential problems: the ordering of the operations in 
the NMI handler was always very fragile, resulting in hard to 
debug hangs - which sometimes needed hours long very intense PMU 
stress-testing to trigger.

That is why I asked how heavily you've tested this. Once the 
series passes review I'll keep this patch last to make it easy 
to revert/zap if it causes problems.

Thanks,

	Ingo

  reply	other threads:[~2013-02-13  9:10 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-02-07 19:23 Basic perf PMU support for Haswell v5 Andi Kleen
2013-02-07 19:23 ` [PATCH 1/5] perf, x86: Add PEBSv2 record support v2 Andi Kleen
2013-02-12  9:02   ` Ingo Molnar
2013-02-07 19:23 ` [PATCH 2/5] perf, x86: Basic Haswell PMU support v4 Andi Kleen
2013-02-07 19:23 ` [PATCH 3/5] perf, x86: Basic Haswell PEBS " Andi Kleen
2013-02-07 19:23 ` [PATCH 4/5] perf, x86: Support full width counting v2 Andi Kleen
2013-02-12  8:42   ` Ingo Molnar
2013-02-07 19:23 ` [PATCH 5/5] perf, x86: Move NMI clearing to end of PMI handler after the counter registers are reset Andi Kleen
2013-02-12  8:43   ` Ingo Molnar
2013-02-12 15:14     ` Andi Kleen
2013-02-13  9:10       ` Ingo Molnar [this message]
  -- strict thread matches above, loose matches on Subject: below --
2013-02-18 18:48 Basic perf PMU support for Haswell v8 Andi Kleen
2013-02-18 18:48 ` [PATCH 5/5] perf, x86: Move NMI clearing to end of PMI handler after the counter registers are reset Andi Kleen
2013-02-13 16:08 Basic perf PMU support for Haswell v7 Andi Kleen
2013-02-13 16:08 ` [PATCH 5/5] perf, x86: Move NMI clearing to end of PMI handler after the counter registers are reset Andi Kleen
2013-02-12 22:04 Basic perf PMU support for Haswell v6 Andi Kleen
2013-02-12 22:04 ` [PATCH 5/5] perf, x86: Move NMI clearing to end of PMI handler after the counter registers are reset Andi Kleen
2013-02-05  1:49 Basic perf PMU support for Haswell v4 Andi Kleen
2013-02-05  1:49 ` [PATCH 5/5] perf, x86: Move NMI clearing to end of PMI handler after the counter registers are reset Andi Kleen
2013-02-02  1:54 Basic perf PMU support for Haswell v3 Andi Kleen
2013-02-02  1:54 ` [PATCH 5/5] perf, x86: Move NMI clearing to end of PMI handler after the counter registers are reset Andi Kleen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20130213091022.GB7630@gmail.com \
    --to=mingo@kernel.org \
    --cc=a.p.zijlstra@chello.nl \
    --cc=acme@infradead.org \
    --cc=ak@linux.intel.com \
    --cc=andi@firstfloor.org \
    --cc=eranian@google.com \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).