From mboxrd@z Thu Jan 1 00:00:00 1970 From: peterz@infradead.org Date: Thu, 24 Sep 2020 10:40:29 +0200 Subject: [Intel-wired-lan] [PATCH v2 1/4] sched/isolation: API to get housekeeping online CPUs In-Reply-To: <20200923181126.223766-2-nitesh@redhat.com> References: <20200923181126.223766-1-nitesh@redhat.com> <20200923181126.223766-2-nitesh@redhat.com> Message-ID: <20200924084029.GC1362448@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: 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 > --- > 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.