On Friday 18 February 2011 15:10:47 Svatopluk Kraus wrote: > Hi, > > I try to figure out locking strategy in FreeBSD and found 'ichsmb' > device. There is a mutex which protects smb bus (ichsmb device). For > example in ichsmb_readw() in sys/dev/ichsmb/ichsmb.c, the mutex is > locked and a command is written to bus, then unbounded (but with > timeout) sleep is done (mutex is unlocked during sleep). After sleep a > word is read from bus and the mutex is unlocked. > > 1. If an use of the device IS NOT serialized by layers around then > more calls to this function (or others) can be started or even done > before the first one is finished. The mutex don't protect sms bus. > > 2. If an use of the device IS serialized by layers around then the > mutex is useless. > > Moreover, I don't mension interrupt routine which uses the mutex and > smb bus too. > > Am I right? Or did I miss something?
man sx ? struct sx ? --HPS _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
