Keith Owens wrote: > > On Thu, 18 Apr 2002 13:37:14 +0400, > "Gleb O. Raiko" <raiko@niisi.msk.ru> wrote: > >If you really hate this behaviour and want to change it, I guess just > >linear serach is OK. > > Performance matters for these tables. It is worth doing one sort at > boot time to let the kernel run faster all the time. For some tables > (ia64 unwind) the API mandates that the table be in ascending order. > No, performance doesn't matter here. First, we are speaking about DBE exception which slowdowns performance. Second, get/put_dbe are used for peripherial accesses which are slow anyway. Third, do you really want to speed up probe routines where those macros are used? I guess, not. Then, how many addresses you have in your dbe_table, 1000 or 6 ? I guess the latter. In the worst case, linear search requires 12 comparisons, while binary search takes 6. 6 extra comparisons is nothing in the dbe handler. If you have more than 6 addresses in the table, just replace macros by routines and get exactly 6. And 6 comparisons, btw, there is no need for loop, just 6 if-statements. I dont't know about other tables and other arches. Perhaps, they need sorting of some tables. But, definetely, sorting isn't required for mips dbe/unaligned access tables. Regards, Gleb.
