Messages in this thread | | | From | Roland Dreier <> | Date | Thu, 13 Jan 2005 07:32:15 -0800 | Subject | Re: [openib-general] [PATCH][5/18] InfiniBand/mthca: add needed rmb() in event queue poll |
| |
Michael> Since we are using the eqe here, it seems that Michael> read_barrier_depends shall be sufficient (as well as in Michael> the cq case)?
Michael> However, I see that read_barrier_depends is a nop on ppc, Michael> and the comment indicates that problems were seen on ppc Michael> 970. What gives? do I misunderstand what a dependency Michael> is?
There is no dependency between the EQE ownership field and the rest of the EQE, so read_barrier_depends() is not sufficient. I think you are misunderstanding what a dependency is. The comments in asm-i386/system.h or http://lse.sourceforge.net/locking/wmbdd.html may help clear things up.
- R. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |