Hi! On Sat, Feb 27, 2010 at 11:05:32AM +0530, Kumar Gopalpet-B05799 wrote: [...] > Understood, and thanks for the explanation. Am I correct in saying that > this is > due to the out-of-order execution capability on powerpc ?
Nope, that was just a logic issue in the driver. Though, with the patch, the eieio() is needed so that compiler (or CPU) won't reorder lstatus and skbuff writes. > I have one more question, why don't we use use atomic_t for num_txbdfree > and > completely do away with spin_locks in gfar_clean_tx_ring() and > gfar_start_xmit(). > In an non-SMP, scenario I would feel there is absolutely no requirement > of spin_locks > and in case of SMP atomic operation would be much more safer on powerpc > rather than spin_locks. > > What is your suggestion ? I think that's a good idea. However, in start_xmit() we'll have to keep the spinlock anyway since it also protects from gfar_error(), which can modify regs->tstat. Thanks! -- Anton Vorontsov email: cbouatmai...@gmail.com irc://irc.freenode.net/bd2 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
