[PATCH 0/3] scsi: scsi-mq: don't hold host_busy in IO path

Ming Lei
2018-04-20T06:59:14Z

Hi,

This patches removes the expensive atomic opeation on host-wide counter
of .host_busy for scsi-mq, and it is observed that IOPS can be increased by
15% with this change in IO test over scsi_debug.

Ming Lei (3):
scsi: introduce scsi_host_busy()
scsi: read host_busy via scsi_host_busy()
scsi: avoid to hold host-wide counter of host_busy for scsi_mq

drivers/scsi/advansys.c | 8 ++++----
drivers/scsi/hosts.c | 32 +++++++++++++++++++++++++++++++
drivers/scsi/libsas/sas_scsi_host.c | 4 ++--
drivers/scsi/megaraid/megaraid_sas_base.c | 2 +-
drivers/scsi/mpt3sas/mpt3sas_base.c | 4 ++--
drivers/scsi/qlogicpti.c | 2 +-
drivers/scsi/scsi.c | 2 +-
drivers/scsi/scsi_error.c | 6 +++---
drivers/scsi/scsi_lib.c | 23 ++++++++++++++++------
drivers/scsi/scsi_sysfs.c | 2 +-
include/scsi/scsi_host.h | 1 +
11 files changed, 65 insertions(+), 21 deletions(-)

Cc: Omar Sandoval <osandov@fb.com>,
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
Cc: James Bottomley <james.bottomley@hansenpartnership.com>,
Cc: Christoph Hellwig <hch@lst.de>,
Cc: Don Brace <don.brace@microsemi.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Laurence Oberman <loberman@redhat.com>

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