Date: Tue, 16 Dec 2008 06:10:04 GMT From: Warner Losh <imp@bsdimp.com> To: freebsd-bugs@FreeBSD.org Subject: Re: kern/118093: firewire bus reset hogs CPU, causing data to be lost Message-ID: <200812160610.mBG6A4we085419@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
The following reply was made to PR kern/118093; it has been noted by GNATS. From: Warner Losh <imp@bsdimp.com> To: freebsd@sopwith.solgatos.com Cc: freebsd-firewire@FreeBSD.org, freebsd-drivers@FreeBSD.org, bug-followup@FreeBSD.org Subject: Re: kern/118093: firewire bus reset hogs CPU, causing data to be lost Date: Mon, 15 Dec 2008 23:01:30 -0700 (MST) > I found the source of this problem. When a firewire bus resets, > the firewire driver prints a few lines to the console, > using printf(9) and device_printf(9). I suspect that these are > running at splfw aka splimp, locking out other i/o. This can't be the case. There's no SPL involved at all. Maybe removing the printfs causes an interrupt to be serviced faster, resulting in what appears to be better performance... > Commenting out the *printf() calls fixes the problem, but that > isn't a good solution. > > Would changing the *printf() calls to log(9) calls be safe? > ("safe" meaning other i/o doesn't get locked out) > > Ah, for the good old days when 19200 baud seemed fast... > _______________________________________________ > freebsd-drivers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-drivers > To unsubscribe, send any mail to "freebsd-drivers-unsubscribe@freebsd.org" > >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200812160610.mBG6A4we085419>