This is a note to let you know that I've just added the patch titled
scsi: megaraid_sas: Load balance completions across all MSI-X
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-megaraid_sas-load-balance-completions-across-al.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 55ce88cf3cd84bb969f14dda7cd9030faffd71b6
Author: Shivasharan S <shivasharan.srikanteshwara@xxxxxxxxxxxx>
Date: Tue May 7 10:05:36 2019 -0700
scsi: megaraid_sas: Load balance completions across all MSI-X
[ Upstream commit 1d15d9098ad12b0021ac5a6b851f26d1ab021e5a ]
Driver will use "reply descriptor post queues" in round robin fashion when
the combined MSI-X mode is not enabled. With this IO completions are
distributed and load balanced across all the available reply descriptor
post queues equally.
This is enabled only if combined MSI-X mode is not enabled in firmware.
This improves performance and also fixes soft lockups.
When load balancing is enabled, IRQ affinity from driver needs to be
disabled.
Signed-off-by: Kashyap Desai <kashyap.desai@xxxxxxxxxxxx>
Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@xxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Stable-dep-of: 0b0747d507bf ("scsi: megaraid_sas: Fix deadlock on firmware crashdump")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index 67d356d847176..80ae48b65b608 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -2193,6 +2193,7 @@ struct megasas_instance {
u32 secure_jbod_support;
u32 support_morethan256jbod; /* FW support for more than 256 PD/JBOD */
bool use_seqnum_jbod_fp; /* Added for PD sequence */
+ bool smp_affinity_enable;
spinlock_t crashdump_lock;
struct megasas_register_set __iomem *reg_set;
@@ -2210,6 +2211,7 @@ struct megasas_instance {
u16 ldio_threshold;
u16 cur_can_queue;
u32 max_sectors_per_req;
+ bool msix_load_balance;
struct megasas_aen_event *ev;
struct megasas_cmd **cmd_list;
@@ -2246,6 +2248,7 @@ struct megasas_instance {
atomic_t sge_holes_type1;
atomic_t sge_holes_type2;
atomic_t sge_holes_type3;
+ atomic64_t total_io_count;
struct megasas_instance_template *instancet;
struct tasklet_struct isr_tasklet;
diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 8d1df03386b4f..2b6b6d3deba86 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -5101,6 +5101,7 @@ megasas_setup_irqs_msix(struct megasas_instance *instance, u8 is_probe)
&instance->irq_context[j]);
/* Retry irq register for IO_APIC*/
instance->msix_vectors = 0;
+ instance->msix_load_balance = false;
if (is_probe) {
pci_free_irq_vectors(instance->pdev);
return megasas_setup_irqs_ioapic(instance);
@@ -5109,6 +5110,7 @@ megasas_setup_irqs_msix(struct megasas_instance *instance, u8 is_probe)
}
}
}
+
return 0;
}
@@ -5364,6 +5366,12 @@ static int megasas_init_fw(struct megasas_instance *instance)
if (rdpq_enable)
instance->is_rdpq = (scratch_pad_2 & MR_RDPQ_MODE_OFFSET) ?
1 : 0;
+
+ if (!instance->msix_combined) {
+ instance->msix_load_balance = true;
+ instance->smp_affinity_enable = false;
+ }
+
fw_msix_count = instance->msix_vectors;
/* Save 1-15 reply post index address to local memory
* Index 0 is already saved from reg offset
@@ -5382,17 +5390,20 @@ static int megasas_init_fw(struct megasas_instance *instance)
instance->msix_vectors);
} else /* MFI adapters */
instance->msix_vectors = 1;
+
/* Don't bother allocating more MSI-X vectors than cpus */
instance->msix_vectors = min(instance->msix_vectors,
(unsigned int)num_online_cpus());
- if (smp_affinity_enable)
+ if (instance->smp_affinity_enable)
irq_flags |= PCI_IRQ_AFFINITY;
i = pci_alloc_irq_vectors(instance->pdev, 1,
instance->msix_vectors, irq_flags);
- if (i > 0)
+ if (i > 0) {
instance->msix_vectors = i;
- else
+ } else {
instance->msix_vectors = 0;
+ instance->msix_load_balance = false;
+ }
}
/*
* MSI-X host index 0 is common for all adapter.
@@ -6447,6 +6458,7 @@ static inline void megasas_init_ctrl_params(struct megasas_instance *instance)
INIT_LIST_HEAD(&instance->internal_reset_pending_q);
atomic_set(&instance->fw_outstanding, 0);
+ atomic64_set(&instance->total_io_count, 0);
init_waitqueue_head(&instance->int_cmd_wait_q);
init_waitqueue_head(&instance->abort_cmd_wait_q);
@@ -6469,6 +6481,8 @@ static inline void megasas_init_ctrl_params(struct megasas_instance *instance)
instance->last_time = 0;
instance->disableOnlineCtrlReset = 1;
instance->UnevenSpanSupport = 0;
+ instance->smp_affinity_enable = smp_affinity_enable ? true : false;
+ instance->msix_load_balance = false;
if (instance->adapter_type != MFI_SERIES) {
INIT_WORK(&instance->work_init, megasas_fusion_ocr_wq);
@@ -6818,7 +6832,7 @@ megasas_resume(struct pci_dev *pdev)
/* Now re-enable MSI-X */
if (instance->msix_vectors) {
irq_flags = PCI_IRQ_MSIX;
- if (smp_affinity_enable)
+ if (instance->smp_affinity_enable)
irq_flags |= PCI_IRQ_AFFINITY;
}
rval = pci_alloc_irq_vectors(instance->pdev, 1,
diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index b400167f9ad42..294e1a3a6adfa 100644
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -2641,8 +2641,13 @@ megasas_build_ldio_fusion(struct megasas_instance *instance,
fp_possible = (io_info.fpOkForIo > 0) ? true : false;
}
- cmd->request_desc->SCSIIO.MSIxIndex =
- instance->reply_map[raw_smp_processor_id()];
+ if (instance->msix_load_balance)
+ cmd->request_desc->SCSIIO.MSIxIndex =
+ (mega_mod64(atomic64_add_return(1, &instance->total_io_count),
+ instance->msix_vectors));
+ else
+ cmd->request_desc->SCSIIO.MSIxIndex =
+ instance->reply_map[raw_smp_processor_id()];
praid_context = &io_request->RaidContext;
@@ -2969,8 +2974,13 @@ megasas_build_syspd_fusion(struct megasas_instance *instance,
cmd->request_desc->SCSIIO.DevHandle = io_request->DevHandle;
- cmd->request_desc->SCSIIO.MSIxIndex =
- instance->reply_map[raw_smp_processor_id()];
+ if (instance->msix_load_balance)
+ cmd->request_desc->SCSIIO.MSIxIndex =
+ (mega_mod64(atomic64_add_return(1, &instance->total_io_count),
+ instance->msix_vectors));
+ else
+ cmd->request_desc->SCSIIO.MSIxIndex =
+ instance->reply_map[raw_smp_processor_id()];
if (!fp_possible) {
/* system pd firmware path */
