On 27/07/2023 02:15, Ming Lei wrote:
hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -2550,6 +2550,9 @@ static int interrupt_preinit_v3_hw(struct hisi_hba *hisi_hba)
hisi_hba->cq_nvecs = vectors - BASE_VECTORS_V3_HW - hisi_hba->iopoll_q_cnt;
+ if (hisi_hba->cq_nvecs > scsi_max_nr_hw_queues())
+ hisi_hba->cq_nvecs = scsi_max_nr_hw_queues();
+
shost->nr_hw_queues = hisi_hba->cq_nvecs + hisi_hba->iopoll_q_cnt;
For other drivers you limit the max MSI vectors which we try to allocate
according to scsi_max_nr_hw_queues(), but here you continue to alloc the
same max vectors but then limit the driver's completion queue count. Why not
limit the max MSI vectors also here?
Ah, checking again, I think that this driver always allocates maximum
possible MSI due to arm interrupt controller driver bug - see comment at
top of function interrupt_preinit_v3_hw(). IIRC, there was a problem if
we remove and re-insert the device driver that the GIC ITS fails to
allocate MSI unless all MSI were previously allocated.
Xiang Chen can confirm.
Good catch!
I guess it is because of the following line:
hisi_hba->cq_nvecs = vectors - BASE_VECTORS_V3_HW - hisi_hba->iopoll_q_cnt;
I am a bit confused why hisi_sas_v3 takes ->iopoll_q_cnt into account
allocated msi vectors? ->iopoll_q_cnt supposes to not consume msi
vectors, so I think we need the following fix first:
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
index 20e1607c6282..032c13ce8373 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -2549,7 +2549,7 @@ static int interrupt_preinit_v3_hw(struct hisi_hba *hisi_hba)
return -ENOENT;
- hisi_hba->cq_nvecs = vectors - BASE_VECTORS_V3_HW - hisi_hba->iopoll_q_cnt;
+ hisi_hba->cq_nvecs = vectors - BASE_VECTORS_V3_HW;
shost->nr_hw_queues = hisi_hba->cq_nvecs + hisi_hba->iopoll_q_cnt;
Thanks,
John
