* Sasha Levin (levinsasha928@xxxxxxxxx) wrote: > On 09/04/2012 07:01 PM, Mathieu Desnoyers wrote: > >> #define do_for_each_ftrace_rec(pg, rec) \ > >> > for (pg = ftrace_pages_start, rec = &pg->records[pg->index]; \ > >> > pg && rec == &pg->records[pg->index]; \ > >> > pg = pg->next) \ > >> > for (rec = pg->records; rec < &pg->records[pg->index]; rec++) > > Maybe in some cases there might be ways to combine the two loops into > > one ? I'm not seeing exactly how to do it for this one, but it should > > not be impossible. If the inner loop condition can be moved to the outer > > loop, and if we use (blah ? loop1_conf : loop2_cond) to test for > > different conditions depending on the context, and do the same for the > > 3rd argument of the for() loop. The details elude me for now though, so > > maybe it's complete non-sense ;) > > > > It might not be that useful for do_for_each_ftrace_rec, but if we can do > > it for the hash table iterator, it might be worth it. > > So I think that for the hash iterator it might actually be simpler. > > My solution to making 'break' work in the iterator is: > > for (bkt = 0, node = NULL; bkt < HASH_SIZE(name) && node == NULL; bkt++) > hlist_for_each_entry(obj, node, &name[bkt], member) > > We initialize our node loop cursor with NULL in the external loop, and the > external loop will have a new condition to loop while that cursor is NULL. > > My logic is that we can only 'break' when we are iterating over an object in the > internal loop. If we're iterating over an object in that loop then 'node != NULL'. > > This way, if we broke from within the internal loop, the external loop will see > node as not NULL, and so it will stop looping itself. On the other hand, if the > internal loop has actually ended, then node will be NULL, and the outer loop > will keep running. > > Is there anything I've missed? This sounds good. Unless I'm missing something too. Thanks! Mathieu > > > Thanks, > Sasha -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
