> From: Greg KH [mailto:gregkh@xxxxxxx] > > + static atomic_t ic_channel_initcnt = ATOMIC_INIT(0); > Why is this an atomic_t? As discussed previously, I used atomic_t to handle more general case if vmbus interrupts happen on every cpu. > > + VmbusChannelOpen(newChannel, 2 * PAGE_SIZE, > > + 2 * PAGE_SIZE, NULL, 0, > > + hv_cb_utils[cnt].callback, > > + newChannel) == 0) { > > + hv_cb_utils[cnt].channel = newChannel; > > + mb(); > > What is the mb() call for? Why is it necessary? (hint, if you need it, > something else is really wrong...) It ensures the channel assignment happens before the wakeup call: osd_WaitEventSet(ic_channel_ready), if the compiler optimization re-arrange the execution order. > Something wierd happened with your indentation here, it doesn't line up > properly. That call to VmbusChannelOpen() needs to go in a full tab, > not 4 spaces. > > Please always run your patch through the checkpatch.pl script before > sending it to me. Sure, I will replace it with TAB. I already ran checkpatch.pl on this patch -- no error: staging-next-2.6> scripts/checkpatch.pl 0525-Fix-race-condition-on-IC-channel-initialization.patch total: 0 errors, 0 warnings, 71 lines checked 0525-Fix-race-condition-on-IC-channel-initialization.patch has no obvious style problems and is ready for submission. > > +struct osd_waitevent *ic_channel_ready; > > What's with the "ic_" naming scheme here? It should be "hv_" right? IC stands for "integration components", such as Shutdown, Timesync, Heartbeat, etc. > As you are using this "ic_channel_ready variable only within the > vmbus_bus_init() call, why not just make it local to there? Then > there's no need to do the create/init/wait/free sequence outside the > init call. > > The init call should just do all of this for us, right? The ic_channel_ready variable is called by VmbusChannelProcessOffer / osd_WaitEventSet(ic_channel_ready) to wake up vmbus_init(). So it's not a local variable. Thanks, - Haiyang _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
