Date: Mon, 19 Feb 2001 20:30:58 -0800 (PST) From: Luigi Rizzo <rizzo@aciri.org> To: imp@FreeBSD.org (Warner Losh) Cc: cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/pci if_dc.c Message-ID: <200102200430.f1K4UxW42792@iguana.aciri.org> In-Reply-To: <200102200421.f1K4LSZ48854@freefall.freebsd.org> from Warner Losh at "Feb 19, 2001 8:21:28 pm"
next in thread | previous in thread | raw e-mail | index | archive | help
> imp 2001/02/19 20:21:28 PST
>
> Modified files:
> sys/pci if_dc.c
> Log:
> Add DC_UNLOCK before first return. This caused returns when dc was on
> a shared interrupt.
sorry for missing that -- but i wonder, can't we just move
the test
if ( (CSR_READ_4(sc, DC_ISR) & DC_INTRS) == 0)
return ;
before the call to DC_LOCK and the assignment to ifp ?
We are just reading from the register here, and the only
possible race that i can think of is someone removing the
descriptor under our feed, which i presume cannot occur.
The whole point of the above patch was avoid paying big cost
when we are called for no reason.
cheers
luigi
----------------------------------+-----------------------------------------
Luigi RIZZO, luigi@iet.unipi.it . ACIRI/ICSI (on leave from Univ. di Pisa)
http://www.iet.unipi.it/~luigi/ . 1947 Center St, Berkeley CA 94704
Phone: (510) 666 2927
----------------------------------+-----------------------------------------
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe cvs-all" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200102200430.f1K4UxW42792>