[PATCH v4 11/14] scsi: lpfc: Use irq_set_affinity

From: Nitesh Narayan Lal
Date: Mon Jul 19 2021 - 14:29:07 EST


The driver uses irq_set_affinity_hint to set the affinity for the lpfc
interrupts to a mask corresponding to the local NUMA node to avoid
performance overhead on AMD architectures.

However, irq_set_affinity_hint() setting the affinity is an undocumented
side effect that this function also sets the affinity under the hood.
To remove this side effect irq_set_affinity_hint() has been marked as
deprecated and new interfaces have been introduced.

Also, as per the commit dcaa21367938 ("scsi: lpfc: Change default IRQ model
on AMD architectures"):
"On AMD architecture, revert the irq allocation to the normal style
(non-managed) and then use irq_set_affinity_hint() to set the cpu affinity
and disable user-space rebalancing."
we don't really need to set the affinity_hint as user-space rebalancing for
the lpfc interrupts is not desired.

Hence, replace the irq_set_affinity_hint() with irq_set_affinity() which
only applies the affinity for the interrupts.

Signed-off-by: Nitesh Narayan Lal <nitesh@xxxxxxxxxx>
---
drivers/scsi/lpfc/lpfc_init.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 5983e05b648f..8a16bacb8c93 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -11455,7 +11455,7 @@ lpfc_irq_set_aff(struct lpfc_hba_eq_hdl *eqhdl, unsigned int cpu)
cpumask_clear(&eqhdl->aff_mask);
cpumask_set_cpu(cpu, &eqhdl->aff_mask);
irq_set_status_flags(eqhdl->irq, IRQ_NO_BALANCING);
- irq_set_affinity_hint(eqhdl->irq, &eqhdl->aff_mask);
+ irq_set_affinity(eqhdl->irq, &eqhdl->aff_mask);
}

/**
@@ -11744,7 +11744,6 @@ lpfc_sli4_enable_msix(struct lpfc_hba *phba)
for (--index; index >= 0; index--) {
eqhdl = lpfc_get_eq_hdl(index);
lpfc_irq_clear_aff(eqhdl);
- irq_set_affinity_hint(eqhdl->irq, NULL);
free_irq(eqhdl->irq, eqhdl);
}

@@ -11905,7 +11904,6 @@ lpfc_sli4_disable_intr(struct lpfc_hba *phba)
for (index = 0; index < phba->cfg_irq_chann; index++) {
eqhdl = lpfc_get_eq_hdl(index);
lpfc_irq_clear_aff(eqhdl);
- irq_set_affinity_hint(eqhdl->irq, NULL);
free_irq(eqhdl->irq, eqhdl);
}
} else {
--
2.27.0