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Date: Fri, 16 Mar 2007 09:17:17 -0400
From: Aniruddha Bohra <bohra@cs.rutgers.edu>
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Subject: ether_input question
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Hi,
 In two drivers, fxp and em, the assumptions about entering the 
ether_input routine are different.
 From em_rxeof:

#ifdef DEVICE_POLLING
 EM_UNLOCK()
(*ifp->if_input)()
EM_UNLOCK()
#else
  (*ifp->if_input)()
#endif

While in fxp:

FXP_UNLOCK()
(*ifp->if_input)()
FXP_LOCK()


My question is :
Does ether_input() assume it is the only thread executing the code? If 
it is the case, what is the
reason for dropping the lock in the DEVICE_POLLING case?

Thanks
Aniruddha