"Peter T. Breuer" wrote: > > "A month of sundays ago Neil Brown wrote:" > > On Monday February 24, Paul.Clements@SteelEye.com wrote: > So it might be enough to chain all the mirror bh's through > bh->b_this_page. That's an interesting idea. I looked through the code and I have some questions: What if the user is waiting on a page and not a buffer (not sure if that can/will happen). In that case, we'd be artificially causing him to wait when it wasn't necessary. Suppose all the I/O for a page really was complete, but we kept the user waiting until all the mirror I/Os (including ones to backup devices) for that page had completed. Another thing I'm not sure about is whether it's safe for raid1 to modify the b_this_page field (for a buffer that was passed in from above)...we'd at least have to insert our values into the existing list. Is it safe to modify the list without any locks held? > I believe that currently this field is just set to "1" in > raid1_make_request(). Yeah, I sure wish I knew who did that and why. I wonder if someone had a clever plan to use that field at some point, but never got around to it. Setting that field to something besides a real address sure does seem odd...and I can't see that it's ever used anywhere. -- Paul - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
