Re: kern/118093: firewire bus reset hogs CPU, causing data to be lost
"M. Warner Losh" <[email protected]>
| Newsgroups | gmane.os.freebsd.devel.firewire |
|---|---|
| Message-ID | <[email protected]> |
In message: <[email protected]> Dieter <[email protected]> writes: : Sean> Which file in dev/firewire are you looking at? : : fwohci.c and firewire.c : : examples: : : printf("non CYCLEMASTER mode\n"); : : device_printf(fc->dev, "Initiate bus reset\n"); : : ------------------- : : Warner> This can't be the case. There's no SPL involved at all. Maybe : Warner> removing the printfs causes an interrupt to be serviced faster, : Warner> resulting in what appears to be better performance... : : With the printfs, Ethernet is not getting serviced. This : is repeatable and easily reproduced. Without the printfs, : it seems ok. : : If it isn't spl, what is locking out Ethernet? interrupt storm? In old-spl-locked drivers, often times the interrupt would be masked while certain operations happened. In new mutex-locked freebsd, there's no way to block the interrupts, so sometimes old code gets into an interrupt storm, which starves other things. Not sure why printf would trigger this, however... Warner _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-firewire To unsubscribe, send any mail to "[email protected]"