"Julio M. Merino Vidal" <[EMAIL PROTECTED]> writes: > Similarly, and if I understood it correctly, the PDA (Per-processor > Data Area) also aims to do the above, but at the moment it only > contains some fields and is not defined in all platforms. There are > still a lot of usages of the percpu functionality (such as, e.g., in > kernel/sched.c).
PDA is an earlier version of percpu; it still can be more efficiently accessed so it is kept for some low level code. > As far as I can tell, the advantage of percpu is that you can define > new "fields" anywhere in the code and independently from the rest of > the system. - Independent maintenance as you noted - Fast access and relatively compact code - Avoids false sharing by keeping cache lines of different CPUs separate - Doesn't waste a lot of memory in padding like NR_CPUs arrays usually need to to avoid the previous point. Any replacement that doesn't have these properties too will probably be not useful. -Andi - 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/