From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <47C02848.70604@domain.hid> Date: Sat, 23 Feb 2008 15:06:00 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <47BF446E.50300@domain.hid> In-Reply-To: <47BF446E.50300@domain.hid> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigB6F1FB0F1A8D9B5E4BAD75B7" Sender: jan.kiszka@domain.hid Subject: Re: [Xenomai-help] gpioirqbench: measuring external interrupt latencies List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wolfgang Grandegger Cc: xenomai-help This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigB6F1FB0F1A8D9B5E4BAD75B7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Wolfgang Grandegger wrote: > Hello, >=20 > I'm proud to announce "gpioirqbench", a benchmark tool to measure > external interrupt latencies. It is derived from Jan's irqbench [1] for= > the PC. Instead of using the serial or parallel port, it uses GPIO pins= > on embedded systems. It measures the time between the generation of an > interrupt triggered by a GPIO pin and the reply by either the interrupt= > service routine, a kernel-space task or a user-space task. As reply, > another GPIO pin will be toggled. The setup consists of two systems, th= e > log host and the test target. The log host triggers the interrupt on th= e > test target and measures the latency. This benchmark is primarily for > Xenomai/RTDM, but it can also be used for plain Linux or even Linux-rt > (with the real-time preemption patch). Nice stuff! Still I have a few conceptual questions: :-> 1. Why do you need a Xenomai measurement host? On first glance, you are just spinning on the reply for the RT target. Why not use plain Linux for this to increase portability? Most beautiful would be a pure userspace approach like for irqbench. What prevents this here? 2. Do you see a chance to integrate the target'S GPIO interface into the exiting irqbench backend? That would make it easy to merge the Xenomai version into the tree. Jan --------------enigB6F1FB0F1A8D9B5E4BAD75B7 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFHwChLniDOoMHTA+kRAs+jAJ9jUJfmoLU1wkEQXuF3XHYUs/2xngCfdjhy IJGENDH9aRF8nr2Xj/CI4UQ= =QbjH -----END PGP SIGNATURE----- --------------enigB6F1FB0F1A8D9B5E4BAD75B7--