On Thu, Sep 13 2007, Linus Torvalds wrote: > > > On Thu, 13 Sep 2007, Jens Axboe wrote: > > > > My bad, I think I added the smp_mb__before_clear_bit() when it was > > __test_and_set_bit() like in the first hunk. > > Ahh, that wouldn't work at all. The "__test_and_set_bit()" thing isn't > atomic at all, and no amount of memory barriers around it would help > (you'd need to use real locking, but at that point the memory barriers are > pointless anyway).
Hence the change, it looks like an oversight from when we didn't allow sharing of tag maps (then the queue lock provided adequate protection). > > + /* > > + * Ensure ordering between ->tag_index[tag] clear and tag clear > > + */ > > + smp_mb__after_clear_bit(); > > You still left this one. But never mind - I already edited your original > patch and it's in my tree with both of those things removed. I took at look at the committed patch and it looks fine, thanks Linus. -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
