[PATCH v2 2/4] mpt3sas: Fix for Crusader to achieve product targets with SAS devices.

From: Chaitra P B
Date: Fri Jan 20 2017 - 09:43:06 EST


Small glitch/degraded performance in Crusader is improved with SAS
drives by removing unnecessary spinlocks while clearing scsi command
in drivers internal lookup table.

Signed-off-by: Chaitra P B <chaitra.basappa@xxxxxxxxxxxx>
Signed-off-by: Suganath Prabu S <suganath-prabu.subramani@xxxxxxxxxxxx>
---
drivers/scsi/mpt3sas/mpt3sas_base.c | 1 +
drivers/scsi/mpt3sas/mpt3sas_base.h | 1 +
drivers/scsi/mpt3sas/mpt3sas_ctl.c | 4 +++-
drivers/scsi/mpt3sas/mpt3sas_scsih.c | 31 ++++++++++++++++++++++++++++---
4 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index f00ef88..722fab9 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -5522,6 +5522,7 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPTER *ioc)
goto out_free_resources;

ioc->non_operational_loop = 0;
+ ioc->got_task_abort_from_ioctl = 0;
return 0;

out_free_resources:
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
index dcb33f4..83cfa16 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.h
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
@@ -1000,6 +1000,7 @@ struct MPT3SAS_ADAPTER {
u8 broadcast_aen_busy;
u16 broadcast_aen_pending;
u8 shost_recovery;
+ u8 got_task_abort_from_ioctl;

struct mutex reset_in_progress_mutex;
spinlock_t ioc_reset_in_progress_lock;
diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
index 95f0f24..02fe1c4 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
@@ -826,16 +826,18 @@ _ctl_do_mpt_command(struct MPT3SAS_ADAPTER *ioc, struct mpt3_ioctl_command karg,
"TASK_MGMT: handle(0x%04x), task_type(0x%02x)\n",
ioc->name,
le16_to_cpu(tm_request->DevHandle), tm_request->TaskType));
-
+ ioc->got_task_abort_from_ioctl = 1;
if (tm_request->TaskType ==
MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK ||
tm_request->TaskType ==
MPI2_SCSITASKMGMT_TASKTYPE_QUERY_TASK) {
if (_ctl_set_task_mid(ioc, &karg, tm_request)) {
mpt3sas_base_free_smid(ioc, smid);
+ ioc->got_task_abort_from_ioctl = 0;
goto out;
}
}
+ ioc->got_task_abort_from_ioctl = 0;

if (test_bit(device_handle, ioc->device_remove_in_progress)) {
dtmprintk(ioc, pr_info(MPT3SAS_FMT
diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
index 0f71f4a..217e0fe 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -1074,6 +1074,26 @@ _scsih_scsi_lookup_get(struct MPT3SAS_ADAPTER *ioc, u16 smid)
}

/**
+ * _scsih_scsi_lookup_get_clear_without_lock - returns scmd entry without
+ * holding any lock.
+ * @ioc: per adapter object
+ * @smid: system request message index
+ *
+ * Returns the smid stored scmd pointer.
+ * Then will dereference the stored scmd pointer.
+ */
+static inline struct scsi_cmnd *
+_scsih_scsi_lookup_get_clear_without_lock(struct MPT3SAS_ADAPTER *ioc,
+ u16 smid)
+{
+ struct scsi_cmnd *scmd = NULL;
+
+ swap(scmd, ioc->scsi_lookup[smid - 1].scmd);
+
+ return scmd;
+}
+
+/**
* _scsih_scsi_lookup_get_clear - returns scmd entry
* @ioc: per adapter object
* @smid: system request message index
@@ -1088,8 +1108,7 @@ _scsih_scsi_lookup_get_clear(struct MPT3SAS_ADAPTER *ioc, u16 smid)
struct scsi_cmnd *scmd;

spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
- scmd = ioc->scsi_lookup[smid - 1].scmd;
- ioc->scsi_lookup[smid - 1].scmd = NULL;
+ scmd = _scsih_scsi_lookup_get_clear_without_lock(ioc, smid);
spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags);

return scmd;
@@ -4659,7 +4678,13 @@ _scsih_io_done(struct MPT3SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply)
unsigned long flags;

mpi_reply = mpt3sas_base_get_reply_virt_addr(ioc, reply);
- scmd = _scsih_scsi_lookup_get_clear(ioc, smid);
+
+ if (ioc->broadcast_aen_busy || ioc->pci_error_recovery ||
+ ioc->got_task_abort_from_ioctl)
+ scmd = _scsih_scsi_lookup_get_clear(ioc, smid);
+ else
+ scmd = _scsih_scsi_lookup_get_clear_without_lock(ioc, smid);
+
if (scmd == NULL)
return 1;

--
1.7.1