From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [PATCH] net/mlx5: Fix mlx5_get_vector_affinity function Date: Sat, 5 May 2018 07:38:38 -0700 Message-ID: <20180505143838.GA12621@roeck-us.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org To: Israel Rukshin Cc: Max Gurtovoy , Matan Barak , Doug Ledford , linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Thomas Gleixner List-Id: linux-rdma@vger.kernel.org On Thu, Apr 12, 2018 at 09:49:11AM +0000, Israel Rukshin wrote: > Adding the vector offset when calling to mlx5_vector2eqn() is wrong. > This is because mlx5_vector2eqn() checks if EQ index is equal to vector number > and the fact that the internal completion vectors that mlx5 allocates > don't get an EQ index. > > The second problem here is that using effective_affinity_mask gives the same > CPU for different vectors. > This leads to unmapped queues when calling it from blk_mq_rdma_map_queues(). > This doesn't happen when using affinity_hint mask. > Except that affinity_hint is only defined if SMP is enabled. Without: include/linux/mlx5/driver.h: In function ‘mlx5_get_vector_affinity_hint’: include/linux/mlx5/driver.h:1299:13: error: ‘struct irq_desc’ has no member named ‘affinity_hint’ Note that this is the only use of affinity_hint outside kernel/irq. Don't other drivers have similar problems ? Guenter > Fixes: 2572cf57d75a ("mlx5: fix mlx5_get_vector_affinity to start from completion vector 0") > Fixes: 05e0cc84e00c ("net/mlx5: Fix get vector affinity helper function") > Signed-off-by: Israel Rukshin > Reviewed-by: Max Gurtovoy > Reviewed-by: Sagi Grimberg > --- > drivers/infiniband/hw/mlx5/main.c | 2 +- > include/linux/mlx5/driver.h | 12 +++--------- > 2 files changed, 4 insertions(+), 10 deletions(-) > > diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c > index daa919e5a442..241cf4ff9901 100644 > --- a/drivers/infiniband/hw/mlx5/main.c > +++ b/drivers/infiniband/hw/mlx5/main.c > @@ -4757,7 +4757,7 @@ mlx5_ib_get_vector_affinity(struct ib_device *ibdev, int comp_vector) > { > struct mlx5_ib_dev *dev = to_mdev(ibdev); > > - return mlx5_get_vector_affinity(dev->mdev, comp_vector); > + return mlx5_get_vector_affinity_hint(dev->mdev, comp_vector); > } > > /* The mlx5_ib_multiport_mutex should be held when calling this function */ > diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h > index 767d193c269a..2a156c5dfadd 100644 > --- a/include/linux/mlx5/driver.h > +++ b/include/linux/mlx5/driver.h > @@ -1284,25 +1284,19 @@ enum { > }; > > static inline const struct cpumask * > -mlx5_get_vector_affinity(struct mlx5_core_dev *dev, int vector) > +mlx5_get_vector_affinity_hint(struct mlx5_core_dev *dev, int vector) > { > - const struct cpumask *mask; > struct irq_desc *desc; > unsigned int irq; > int eqn; > int err; > > - err = mlx5_vector2eqn(dev, MLX5_EQ_VEC_COMP_BASE + vector, &eqn, &irq); > + err = mlx5_vector2eqn(dev, vector, &eqn, &irq); > if (err) > return NULL; > > desc = irq_to_desc(irq); > -#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK > - mask = irq_data_get_effective_affinity_mask(&desc->irq_data); > -#else > - mask = desc->irq_common_data.affinity; > -#endif > - return mask; > + return desc->affinity_hint; > } > > #endif /* MLX5_DRIVER_H */ > -- > 2.7.4