Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20200407063345.4484-1-Jason@zx2c4.com> <20200407063345.4484-3-Jason@zx2c4.com>
 <0e189a4fe1e69b08afc859ce83623a0e5ea0c08b.camel@linux.intel.com>
In-Reply-To: <0e189a4fe1e69b08afc859ce83623a0e5ea0c08b.camel@linux.intel.com>
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
Date:   Mon, 13 Apr 2020 22:21:08 -0600
Message-ID: <CAHmME9pigvAgK3Bje6DkFEcdyWwi7-C7D6QEo4YiH_cbJvxqhQ@mail.gmail.com>
Subject: Re: [PATCH 3/3] x86/mce/therm_throt: allow disabling the thermal
 vector altogether
To:     Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, linux-edac@vger.kernel.org,
        X86 ML <x86@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        bberg@redhat.com, bp@suse.de
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Apr 13, 2020 at 9:38 PM Srinivas Pandruvada
<srinivas.pandruvada@linux.intel.com> wrote:
>
> On Tue, 2020-04-07 at 00:33 -0600, Jason A. Donenfeld wrote:
> > The thermal IRQ handler uses 1.21% CPU on my system when it's hot
> > from
> > compiling things. Indeed looking at /proc/interrupts reveals quite a
> > lot
> I am curious why you are hitting threshold frequently?
> What is rdmsr 0x1a2

5640000

> > of events coming in. Beyond logging them, the existing drivers on the
> > system don't appear to do very much that I'm interested in. So, add a
> > way to disable this entirely so that I can regain precious CPU
> > cycles.
> It is showing amount of time system is running in a constrained
> environment. Lots of real time and HPC folks really care about this.

Which is why this patch adds an option, not a full removal or
something. Real time and HPC people can keep their expensive
interrupt. Other people with different varieties of system can disable
it.