Oleg Drokin <gr...@linuxhacker.ru> writes: > Thanks! > Seems there was a midair collsion with my own patch that was not as > comprehensive > wrt functions touched: https://lkml.org/lkml/2015/3/2/10
Yep, I posted this for completeness (and for your reference), but figured you'd handle it. > But on the other hand I also tried to clean up > some of the NR_CPUS usage while I was at it and this raises > this question, from me, in the code like: > > for_each_cpu_mask(i, blah) { > blah > if (something) > break; > } > if (i == NR_CPUS) > blah; > > when we are replacing for_each_cpu_mask with for_each_cpu, > what do we check the counter against now to see that the entire loop was > executed > and we did not exit prematurely? nr_cpu_ids? You want >= nr_cpu_ids here. > Also I assume we still want to get rid of direct cpumask assignments like >> mask = *cpumask_of_node(cpu_to_node(index)); Yes, but this code is wrong anyway: mask = *cpumask_of_node(cpu_to_node(index)); for (i = max; i < num_online_cpus(); i++) cpumask_clear_cpu(i, &mask); *Never* iterate to num_online_cpus(). eg. if cpus 0 and 3 are online, num_online_cpus() == 2. I'm not sure what this code is doing, but it's not doing it well :) There are several issues here. You need to handle cpus going offline (during this routine, as well as after). You need to use a cpumask_var_t, like so: cpumask_var_t mask; ... case PDB_POLICY_NEIGHBOR: if (!alloc_cpumask_var(&mask, GFP_???)) { rc = -ENOMEM; break; } ... Or get rid of the mask altogether, eg: pc->pc_npartners = -1; for_each_cpu(i, cpu_online_mask) { if (i < max) pc->pc_npartners++; } ... pidx = 0; for_each_cpu(i, cpu_online_mask) { if (i >= max) break; ppc = &ptlrpcds->pd_threads[i]; pc->pc_partners[pidx++] = ppc; ppc->pc_partners[ppc->pc_npartners++] = pc; } [ This is off the top of my head, no idea if it's right...] Thanks, Rusty. -- 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/