[PATCH V2 3/3] scsi: mptxsas: offload IRQ execution

From: Sinan Kaya
Date: Sun Nov 08 2015 - 20:58:49 EST


The mpt2sas and mpt3sas drivers are spinning forever in
their IRQ handlers if there are a lot of jobs queued up
by the PCIe card. This handler is causing spikes for
the rest of the system and sluggish behavior.

Marking all MSI interrupts as non-shared and moving the
MSI interrupts to thread context. This relexes the rest
of the system execution.

Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
drivers/scsi/mpt2sas/mpt2sas_base.c | 12 ++++++++----
drivers/scsi/mpt3sas/mpt3sas_base.c | 13 +++++++++----
2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index c61c82a..b619a0e 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -1359,14 +1359,18 @@ _base_request_irq(struct MPT2SAS_ADAPTER *ioc, u8 index, u32 vector)
cpumask_clear(reply_q->affinity_hint);

atomic_set(&reply_q->busy, 0);
- if (ioc->msix_enable)
+ if (ioc->msix_enable) {
snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d-msix%d",
MPT2SAS_DRIVER_NAME, ioc->id, index);
- else
+ r = request_threaded_irq(vector, NULL, _base_interrupt,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ reply_q->name, reply_q);
+ } else {
snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d",
MPT2SAS_DRIVER_NAME, ioc->id);
- r = request_irq(vector, _base_interrupt, IRQF_SHARED, reply_q->name,
- reply_q);
+ r = request_irq(vector, _base_interrupt, IRQF_SHARED,
+ reply_q->name, reply_q);
+ }
if (r) {
printk(MPT2SAS_ERR_FMT "unable to allocate interrupt %d!\n",
reply_q->name, vector);
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 6dc391c..62bee43 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -1661,14 +1661,19 @@ _base_request_irq(struct MPT3SAS_ADAPTER *ioc, u8 index, u32 vector)
cpumask_clear(reply_q->affinity_hint);

atomic_set(&reply_q->busy, 0);
- if (ioc->msix_enable)
+ if (ioc->msix_enable) {
snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d-msix%d",
MPT3SAS_DRIVER_NAME, ioc->id, index);
- else
+
+ r = request_threaded_irq(vector, NULL, _base_interrupt,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ reply_q->name, reply_q);
+ } else {
snprintf(reply_q->name, MPT_NAME_LENGTH, "%s%d",
MPT3SAS_DRIVER_NAME, ioc->id);
- r = request_irq(vector, _base_interrupt, IRQF_SHARED, reply_q->name,
- reply_q);
+ r = request_irq(vector, _base_interrupt, IRQF_SHARED,
+ reply_q->name, reply_q);
+ }
if (r) {
pr_err(MPT3SAS_FMT "unable to allocate interrupt %d!\n",
reply_q->name, vector);
--
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project

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