On Wed, Sep 23, 2020 at 02:11:23PM -0400, Nitesh Narayan Lal wrote: > Introduce a new API hk_num_online_cpus(), that can be used to > retrieve the number of online housekeeping CPUs that are meant to handle > managed IRQ jobs. > > This API is introduced for the drivers that were previously relying only > on num_online_cpus() to determine the number of MSIX vectors to create. > In an RT environment with large isolated but fewer housekeeping CPUs this > was leading to a situation where an attempt to move all of the vectors > corresponding to isolated CPUs to housekeeping CPUs were failing due to > per CPU vector limit. > > Signed-off-by: Nitesh Narayan Lal <nitesh@xxxxxxxxxx> > --- > include/linux/sched/isolation.h | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h > index cc9f393e2a70..2e96b626e02e 100644 > --- a/include/linux/sched/isolation.h > +++ b/include/linux/sched/isolation.h > @@ -57,4 +57,17 @@ static inline bool housekeeping_cpu(int cpu, enum hk_flags flags) > return true; > } > > +static inline unsigned int hk_num_online_cpus(void) This breaks with the established naming of that header.
