diff options
| author |   Dmitry Bogdanov <d.bogdanov@yadro.com> | 2021-09-14 13:55:39 +0300 |
|---|---|---|
| committer |   Martin K. Petersen <martin.petersen@oracle.com> | 2021-09-22 00:04:56 -0400 |
| commit | e76b7c5e25a1fa818bb3e727873a899cc89f5196 (patch) | |
| tree | 4b5faf223d55af02c8bc96c973dee6bccdb2763e | |
| parent | scsi: efct: Fix nport free (diff) | |
| download | linux-dev-e76b7c5e25a1fa818bb3e727873a899cc89f5196.tar.xz linux-dev-e76b7c5e25a1fa818bb3e727873a899cc89f5196.zip | |
scsi: efct: Decrease area under spinlock
Under the session level spinlock node->active_ios_lock in
efct_scsi_io_alloc() we are taking another spinlock for the port. This
leads to contention between sessions and even between I/Os in the same
session.
Reduce the locked region to active_ios list for which active_ios_lock is
intended. Spinlock CPU usage decreases from 18% down to 13%. IOPS are
increased from 220 kIOPS to 264 kIOPS for one LUN.
Link: https://lore.kernel.org/r/20210914105539.6942-4-d.bogdanov@yadro.com
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Ram Vegesna <ram.vegesna@broadcom.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| -rw-r--r-- | drivers/scsi/elx/efct/efct_scsi.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/scsi/elx/efct/efct_scsi.c b/drivers/scsi/elx/efct/efct_scsi.c index 40fb3a724c76..8535bb7eabd8 100644 --- a/drivers/scsi/elx/efct/efct_scsi.c +++ b/drivers/scsi/elx/efct/efct_scsi.c @@ -38,8 +38,6 @@ efct_scsi_io_alloc(struct efct_node *node) xport = efct->xport; - spin_lock_irqsave(&node->active_ios_lock, flags); - io = efct_io_pool_io_alloc(efct->xport->io_pool); if (!io) { efc_log_err(efct, "IO alloc Failed\n"); @@ -66,6 +64,7 @@ efct_scsi_io_alloc(struct efct_node *node) /* Add to node's active_ios list */ INIT_LIST_HEAD(&io->list_entry); + spin_lock_irqsave(&node->active_ios_lock, flags); list_add(&io->list_entry, &node->active_ios); spin_unlock_irqrestore(&node->active_ios_lock, flags); |