Em Wednesday 30 July 2008 12:02:30 Michael Buesch escreveu: > On Wednesday 30 July 2008 16:53:13 Herton Ronaldo Krzesinski wrote: > > Em Wednesday 30 July 2008 10:27:26 Michael Buesch escreveu: > > > On Wednesday 30 July 2008 15:24:40 Michael Buesch wrote: <snip> > > > and the mutex name, of course. > > > > > > /* Mutex to protect the device configuration data, > > > * which is foobar and bizzbaz */ > > > struct mutex conf_mutex; > > > > Yes, it's better this way. About the lock, the problem here is you can't > > set the channel while transmitting data on 8187 (the card stops working > > util reset like the comment on the code), so we must enable tx loopback > > while setting channels, but you can't run rtl8187_config concurrently > > because one instance may be disabling tx loopback while other is still > > setting channel, or like the code is today there is a possibility that > > you set tx loopback forever. The lock could be only in that section. > > > > The comment could be: > > /* Mutex to protect the device configuration data, > > * we can't set channels concurrently */ > > I think you probably want to protect the tx-loopback (enabled or disabled) > state. That's what you're actually doing implicitely. The problem is not > any channel concurrency or something like that, but that the > tx-loopback-enable/disable is not recursive is the real thing we want to > lock here, probably. No, the issue is that I must enter in tx-loopback mode to set the channels inside rtl8187_config, to avoid transmission of packets, so the hardware doesn't halt. So that's why the lock, it must cover the entire section of "enable loopback"->"set_chan"->"disable loopback", not only the state of TX_CONF register. > > Note that I didn't read the code. > But in general you get the idea. Don't lock code, but lock state data. > (like the loopback-state data). -- []'s Herton -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
