scsi: lpfc: Fix interrupt assignments when multiple vectors are supported on same CPU

With certain platforms its possible pci_alloc_irq_vectors() may affinitize
irq vectors to multiple (all?) CPUs. The driver is currently assuming
exclusivity and vectors being doled out to different CPUs and is assigning
primary ownership of each vector to the first CPU in the mask.  The code
doesn't bother to check if the CPU already owns a vector and will
unconditionally overwrite the CPU to vector mapping. This causes the
relationships between eq's and cq's to get confused and gets worse when
CPUs start to offline. The net results are interrupts are skipped resulting
in mailbox timeouts and there are oopses in CPU offling flows.

Fix this changing up the primary vector assignment. Now assign the eq to a
CPU only if it is the CPU in the mask that does not have a prior
assignment. And once the primary ownership is assigned, break from the
loop. For CPUs that may have been set before but not the primary owner, the
lpfc_cpu_affinity_check() routine will balance the CPU to eq assignment.

Link: https://lore.kernel.org/r/20200706204230.130363-1-jsmart2021@gmail.com
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

0 files changed, 0 insertions, 0 deletions