From 9c8cce8e416b3286720379b5efa1c7fa81b2ec36 Mon Sep 17 00:00:00 2001 From: Robert Love Date: Fri, 1 Apr 2011 16:06:14 -0700 Subject: [PATCH] [SCSI] libfc: Move host_lock usage into ramp_up/down routines The host_lock is still used to protect the can_queue value in the Scsi_Host, but it doesn't need to be held and released by each caller. This patch moves the lock usage into the fc_fcp_can_queue_ramp_up and fc_fcp_can_queue_ramp_down routines. Signed-off-by: Robert Love Tested-by: Ross Brattain Signed-off-by: James Bottomley --- drivers/scsi/libfc/fc_fcp.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c index 5b799a37ad09..3591b872dd0e 100644 --- a/drivers/scsi/libfc/fc_fcp.c +++ b/drivers/scsi/libfc/fc_fcp.c @@ -335,22 +335,23 @@ static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp) /** * fc_fcp_can_queue_ramp_up() - increases can_queue * @lport: lport to ramp up can_queue - * - * Locking notes: Called with Scsi_Host lock held */ static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); + unsigned long flags; int can_queue; + spin_lock_irqsave(lport->host->host_lock, flags); + if (si->last_can_queue_ramp_up_time && (time_before(jiffies, si->last_can_queue_ramp_up_time + FC_CAN_QUEUE_PERIOD))) - return; + goto unlock; if (time_before(jiffies, si->last_can_queue_ramp_down_time + FC_CAN_QUEUE_PERIOD)) - return; + goto unlock; si->last_can_queue_ramp_up_time = jiffies; @@ -362,6 +363,9 @@ static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport) lport->host->can_queue = can_queue; shost_printk(KERN_ERR, lport->host, "libfc: increased " "can_queue to %d.\n", can_queue); + +unlock: + spin_unlock_irqrestore(lport->host->host_lock, flags); } /** @@ -373,18 +377,19 @@ static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport) * commands complete or timeout, then try again with a reduced * can_queue. Eventually we will hit the point where we run * on all reserved structs. - * - * Locking notes: Called with Scsi_Host lock held */ static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); + unsigned long flags; int can_queue; + spin_lock_irqsave(lport->host->host_lock, flags); + if (si->last_can_queue_ramp_down_time && (time_before(jiffies, si->last_can_queue_ramp_down_time + FC_CAN_QUEUE_PERIOD))) - return; + goto unlock; si->last_can_queue_ramp_down_time = jiffies; @@ -395,6 +400,9 @@ static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport) lport->host->can_queue = can_queue; shost_printk(KERN_ERR, lport->host, "libfc: Could not allocate frame.\n" "Reducing can_queue to %d.\n", can_queue); + +unlock: + spin_unlock_irqrestore(lport->host->host_lock, flags); } /* @@ -409,16 +417,13 @@ static inline struct fc_frame *fc_fcp_frame_alloc(struct fc_lport *lport, size_t len) { struct fc_frame *fp; - unsigned long flags; fp = fc_frame_alloc(lport, len); if (likely(fp)) return fp; /* error case */ - spin_lock_irqsave(lport->host->host_lock, flags); fc_fcp_can_queue_ramp_down(lport); - spin_unlock_irqrestore(lport->host->host_lock, flags); return NULL; }