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author | Jacob Keller <jacob.e.keller@intel.com> | 2017-07-14 09:10:10 -0400 |
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committer | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2017-08-27 16:09:03 -0700 |
commit | 759dc4a7e605e0dc21708b0a6e0816ed0ac82641 (patch) | |
tree | b4184ae7eed8c240d95ebae1f63b8100f1c3501a /drivers/net/ethernet/intel/i40evf/i40evf_main.c | |
parent | 9254c0e34e4253c41fdcd4670b754506ce20d3eb (diff) | |
download | talos-op-linux-759dc4a7e605e0dc21708b0a6e0816ed0ac82641.tar.gz talos-op-linux-759dc4a7e605e0dc21708b0a6e0816ed0ac82641.zip |
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/i40evf/i40evf_main.c')
-rw-r--r-- | drivers/net/ethernet/intel/i40evf/i40evf_main.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/net/ethernet/intel/i40evf/i40evf_main.c b/drivers/net/ethernet/intel/i40evf/i40evf_main.c index 9ee277e87f10..1825d956bb00 100644 --- a/drivers/net/ethernet/intel/i40evf/i40evf_main.c +++ b/drivers/net/ethernet/intel/i40evf/i40evf_main.c @@ -584,8 +584,10 @@ i40evf_request_traffic_irqs(struct i40evf_adapter *adapter, char *basename) q_vector->affinity_notify.release = i40evf_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)); } return 0; @@ -1456,6 +1458,7 @@ static int i40evf_alloc_q_vectors(struct i40evf_adapter *adapter) q_vector->adapter = adapter; q_vector->vsi = &adapter->vsi; q_vector->v_idx = q_idx; + cpumask_copy(&q_vector->affinity_mask, cpu_possible_mask); netif_napi_add(adapter->netdev, &q_vector->napi, i40evf_napi_poll, NAPI_POLL_WEIGHT); } |