From: Mario Smarduch <m.smarduch@samsung.com>
To: "linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
mark.rutland@arm.com, Will Deacon <will.deacon@arm.com>,
Marc Zyngier <Marc.Zyngier@arm.com>,
Catalin Marinas <catalin.marinas@arm.com>,
Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: wim@iguana.be, Christoffer Dall <christoffer.dall@linaro.org>,
linux-watchdog@vger.kernel.org
Subject: arm/arm64 HARDLOCKUP Detector and PERF NMI support
Date: Sat, 09 Jan 2016 16:13:48 -0800 [thread overview]
Message-ID: <5691A23C.8060807@samsung.com> (raw)
In-Reply-To: <569199C0.9030500@samsung.com>
I'm trying to get HARDLOCKUP detector to work on arm (on foundation
model and Juno, but armv7 should have the same issue). Turns out there is no
PERF NMI support (HAVE_PERF_EVENTS_NMI), which I guess would be PMU NMI - I
tested overflow on cycle counter and PMU interrupts can be masked. HARDLOCKUP
assumes perf interrupts are non-maskable and uses the PMU to program an NMI to
detect hard lockup and that in turn drives softlockup detection.
Is there something, someplace in ARM manuals that addresses this, searched the
manuals but couldn't find anything?
Or other approaches that I'm not aware off or have floated on the mailing list.
It's a pretty important feature for some environments.
- Mario
next parent reply other threads:[~2016-01-10 0:23 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <569199C0.9030500@samsung.com>
2016-01-10 0:13 ` Mario Smarduch [this message]
2016-01-11 10:26 ` arm/arm64 HARDLOCKUP Detector and PERF NMI support Mark Rutland
2016-01-11 10:26 ` Mark Rutland
2016-01-11 11:25 ` Daniel Thompson
2016-01-11 11:25 ` Daniel Thompson
2016-01-11 20:06 ` Mario Smarduch
2016-01-11 20:06 ` Mario Smarduch
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=5691A23C.8060807@samsung.com \
--to=m.smarduch@samsung.com \
--cc=Marc.Zyngier@arm.com \
--cc=catalin.marinas@arm.com \
--cc=christoffer.dall@linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-watchdog@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=mark.rutland@arm.com \
--cc=will.deacon@arm.com \
--cc=wim@iguana.be \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.