On Tue, 15 Apr 2014, Paul E. McKenney wrote: > Hello, Christoph, > > I have a patch that currently uses __this_cpu_inc_return() to increment a > per-CPU variable, but without preemption disabled. Of course, given that > preemption is enabled, it might well end up picking up one CPU's counter, > adding one to it, then storing the result into some other CPU's counter. > But this is OK, the test can be probabilistic. And when I run this > against v3.14 and earlier, it works fine.
We introduced raw_cpu_inc_return to squish these warnings. > This is arguably better than the original __this_cpu_read() because it > avoids overflow, but I thought I should check to see if there was some > better way to do this. If this is supposed to be totally race safe then you must disable preemption. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
