On Thu, 5 Oct 2017 10:37:59 -0500 Julia Cartwright <ju...@ni.com> wrote:
> On Thu, Oct 05, 2017 at 05:27:30PM +0200, Thomas Gleixner wrote: > > On Thu, 5 Oct 2017, Julia Cartwright wrote: > > > On Tue, Oct 03, 2017 at 12:49:19PM -0300, Arnaldo Carvalho de Melo wrote: > > > > > > > - preempt_disable(); > > > > + preempt_disable_nort(); > > > > this_cpu_inc(*sc->buffers_allocated); > > > > > > Have you tried this on RT w/ CONFIG_DEBUG_PREEMPT? I believe that the > > > this_cpu_* operations perform a preemption check, which we'd trip. > > > > Good point. Changing this to migrate_disable() would do the trick. > > Wouldn't we still trip the preempt check even with migration disabled? > In another thread I asked the same question: should the preemption > checks here be converted to migration-checks in RT? Is it a "preemption check"? Getting a cpu # should only care about migration. This isn't the same as a rcu_sched check is it? That does care about preemption. -- Steve
