diff options
| author | Jacob Keller <jacob.e.keller@intel.com> | 2017-07-14 16:10:10 +0300 |
|---|---|---|
| committer | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2017-08-28 02:09:03 +0300 |
| commit | 759dc4a7e605e0dc21708b0a6e0816ed0ac82641 (patch) | |
| tree | b4184ae7eed8c240d95ebae1f63b8100f1c3501a /drivers/net/ethernet/intel/i40e | |
| parent | 9254c0e34e4253c41fdcd4670b754506ce20d3eb (diff) | |
| download | linux-759dc4a7e605e0dc21708b0a6e0816ed0ac82641.tar.xz | |
i40e: initialize our affinity_mask based on cpu_possible_mask
On older kernels a call to irq_set_affinity_hint does not guarantee that
the IRQ affinity will be set. If nothing else on the system sets the IRQ
affinity this can result in a bug in the i40e_napi_poll() routine where
we notice that our interrupt fired on the "wrong" CPU according to our
internal affinity_mask variable.
This results in a bug where we continuously tell NAPI to stop polling to
move the interrupt to a new CPU, but the CPU never changes because our
affinity mask does not match the actual mask setup for the IRQ.
The root problem is a mismatched affinity mask value. So lets initialize
the value to cpu_possible_mask instead. This ensures that prior to the
first time we get an IRQ affinity notification we'll have the mask set
to include every possible CPU.
We use cpu_possible_mask instead of cpu_online_mask since the former is
almost certainly never going to change, while the later might change
after we've made a copy.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net/ethernet/intel/i40e')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_main.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index 7366e7c7f399..6498da8806cb 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -2881,7 +2881,7 @@ static void i40e_config_xps_tx_ring(struct i40e_ring *ring) if ((vsi->tc_config.numtc <= 1) && !test_and_set_bit(__I40E_TX_XPS_INIT_DONE, &ring->state)) { netif_set_xps_queue(ring->netdev, - &ring->q_vector->affinity_mask, + get_cpu_mask(ring->q_vector->v_idx), ring->queue_index); } @@ -3506,8 +3506,10 @@ static int i40e_vsi_request_irq_msix(struct i40e_vsi *vsi, char *basename) q_vector->affinity_notify.notify = i40e_irq_affinity_notify; q_vector->affinity_notify.release = i40e_irq_affinity_release; irq_set_affinity_notifier(irq_num, &q_vector->affinity_notify); - /* assign the mask for this irq */ - irq_set_affinity_hint(irq_num, &q_vector->affinity_mask); + /* get_cpu_mask returns a static constant mask with + * a permanent lifetime so it's ok to use here. + */ + irq_set_affinity_hint(irq_num, get_cpu_mask(q_vector->v_idx)); } vsi->irqs_ready = true; @@ -4289,7 +4291,7 @@ static void i40e_vsi_free_irq(struct i40e_vsi *vsi) /* clear the affinity notifier in the IRQ descriptor */ irq_set_affinity_notifier(irq_num, NULL); - /* clear the affinity_mask in the IRQ descriptor */ + /* remove our suggested affinity mask for this IRQ */ irq_set_affinity_hint(irq_num, NULL); synchronize_irq(irq_num); free_irq(irq_num, vsi->q_vectors[i]); @@ -8235,7 +8237,7 @@ static int i40e_vsi_alloc_q_vector(struct i40e_vsi *vsi, int v_idx, int cpu) q_vector->vsi = vsi; q_vector->v_idx = v_idx; - cpumask_set_cpu(cpu, &q_vector->affinity_mask); + cpumask_copy(&q_vector->affinity_mask, cpu_possible_mask); if (vsi->netdev) netif_napi_add(vsi->netdev, &q_vector->napi, |