Messages in this thread | | | Date | Tue, 13 Aug 2019 07:30:27 -0700 | From | "" <> | Subject | Re: [PATCH] RISC-V: Issue a local tlb flush if possible. |
| |
On Tue, Aug 13, 2019 at 12:15:15AM +0000, Atish Patra wrote: > I thought if it recieves an empty cpumask, then it should at least do a > local flush is the expected behavior. Are you saying that we should > just skip all and return ?
How could we ever receive an empty cpu mask? I think it could only be empty without the current cpu. At least that is my reading of the callers and a few other implementations.
> > if (!cpumask || cpumask_test_cpu(cpu, cpumask) { > > if ((start == 0 && size == -1) || size > PAGE_SIZE) > > local_flush_tlb_all(); > > else if (size == PAGE_SIZE) > > local_flush_tlb_page(start); > > cpumask_clear_cpu(cpuid, cpumask); > > This will modify the original cpumask which is not correct. clear part > has to be done on hmask to avoid a copy.
Indeed. But looking at the x86 tlbflush implementation it seems like we could use cpumask_any_but() to avoid having to modify the passed in cpumask.
| |