From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <46D30203.9070001@domain.hid> Date: Mon, 27 Aug 2007 18:55:31 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <10837d740708262338w2def2f9er8fd2ca589e681992@domain.hid> <46D2A840.8040301@domain.hid> <10837d740708270654j3bf3849aq3eef304a7cf502a5@domain.hid> In-Reply-To: <10837d740708270654j3bf3849aq3eef304a7cf502a5@domain.hid> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigC009678F7EEF8CD5CCE06779" Sender: jan.kiszka@domain.hid Subject: Re: [Adeos-main] RT ISR re-entrance List-Id: General discussion about Adeos List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?GB2312?B?1cW+pw==?= <2hang.j1ng.home@domain.hid> Cc: adeos-main@gna.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigC009678F7EEF8CD5CCE06779 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: quoted-printable =D5=C5=BE=A7 wrote: > hi, >=20 > Thank you for your reply! >=20 > 2007/8/27, Jan Kiszka : >> ?? wrote: >>> hi all, >>> >>> In SMP system, an edge triggerred interrupt may be dispatched to >> multiple >>> cpus, so the RT ISR of this interrupt may be involved on multiple cpu= s >> at >>> the same time. The question comes: is RT ISR need to be reentrant as >>> designed or do I miss something? >> Good question. I would say: yes, it's the I-pipe user's job to take ca= re >> of re-entrance safety. >> >> Vanilla Linux prevents this via the IRQ_INPROGRESS flag. Xenomai 2.4 a= nd >> since 2.3.2 achieves re-entrance protection for the registered driver >> handler by holding the IRQ-related spinlock while calling into that >> handler. >=20 >=20 > AFAIK, Xenomai 2.3.3 simply uses the IRQ dispatcher of i-pipe and do no= t > supply its own dispatcher. The Xenomai nucleus does dispatch - to the registered handler(s). >=20 > Still, this isn't something the user should build his system >> upon. It is rather recommended for determinism and efficiency reasons = to >> assign RT IRQs to a specific CPU. >=20 >=20 > Good suggestion=A3=A1Thanks again! >=20 > HTH, >> Jan >> >> >> Jan --------------enigC009678F7EEF8CD5CCE06779 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFG0wIDniDOoMHTA+kRAni0AJ99QWlQVVJbKtL5Tnua9Oy26BF3gACfXN6z 9S4949JNOKTUo1SPpkkjzoc= =2ro/ -----END PGP SIGNATURE----- --------------enigC009678F7EEF8CD5CCE06779--