On Thu, 17 Oct 2019 at 09:47, Peter Zijlstra <[email protected]> wrote: > > On Wed, Oct 16, 2019 at 09:34:05PM +0200, Marco Elver wrote: > > On Wed, 16 Oct 2019 at 20:44, Peter Zijlstra <[email protected]> wrote: > > > > + /* > > > > + * Disable interrupts & preemptions, to ignore races due to > > > > accesses in > > > > + * threads running on the same CPU. > > > > + */ > > > > + local_irq_save(irq_flags); > > > > + preempt_disable(); > > > > > > Is there a point to that preempt_disable() here? > > > > We want to avoid being preempted while the watchpoint is set up; > > otherwise, we would report data-races for CPU-local data, which is > > incorrect. > > Disabling IRQs already very much disables preemption. There is > absolutely no point in doing preempt_disable() when the whole section > already runs with IRQs disabled.
Ah thanks for the clarification, in that case I assume it's safe to remove preempt_disable() for v2. > -- > You received this message because you are subscribed to the Google Groups > "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/kasan-dev/20191017074730.GW2328%40hirez.programming.kicks-ass.net.
