From 43fac4d97a1a30085f1cae61aa565e5e7e5e5d7d Mon Sep 17 00:00:00 2001 From: Anirban Chakraborty Date: Wed, 10 Jun 2009 13:55:11 -0700 Subject: [PATCH] [SCSI] qla2xxx: Resolve a performance issue in interrupt Reverted back a change in qla*_intr_handler code that caused an increase in cpu cycles by allowing interrupts to occur while the instance hardware lock was being held. Fix by taking the lock in irqsave mode. Reported-and-tested-by: Douglas W. Styner Signed-off-by: Anirban Chakraborty Signed-off-by: James Bottomley --- drivers/scsi/qla2xxx/qla_isr.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c index c8d0a17..245e7af 100644 --- a/drivers/scsi/qla2xxx/qla_isr.c +++ b/drivers/scsi/qla2xxx/qla_isr.c @@ -37,6 +37,7 @@ qla2100_intr_handler(int irq, void *dev_id) uint16_t hccr; uint16_t mb[4]; struct rsp_que *rsp; + unsigned long flags; rsp = (struct rsp_que *) dev_id; if (!rsp) { @@ -49,7 +50,7 @@ qla2100_intr_handler(int irq, void *dev_id) reg = &ha->iobase->isp; status = 0; - spin_lock(&ha->hardware_lock); + spin_lock_irqsave(&ha->hardware_lock, flags); vha = pci_get_drvdata(ha->pdev); for (iter = 50; iter--; ) { hccr = RD_REG_WORD(®->hccr); @@ -101,7 +102,7 @@ qla2100_intr_handler(int irq, void *dev_id) RD_REG_WORD(®->hccr); } } - spin_unlock(&ha->hardware_lock); + spin_unlock_irqrestore(&ha->hardware_lock, flags); if (test_bit(MBX_INTR_WAIT, &ha->mbx_cmd_flags) && (status & MBX_INTERRUPT) && ha->flags.mbox_int) { @@ -133,6 +134,7 @@ qla2300_intr_handler(int irq, void *dev_id) uint16_t mb[4]; struct rsp_que *rsp; struct qla_hw_data *ha; + unsigned long flags; rsp = (struct rsp_que *) dev_id; if (!rsp) { @@ -145,7 +147,7 @@ qla2300_intr_handler(int irq, void *dev_id) reg = &ha->iobase->isp; status = 0; - spin_lock(&ha->hardware_lock); + spin_lock_irqsave(&ha->hardware_lock, flags); vha = pci_get_drvdata(ha->pdev); for (iter = 50; iter--; ) { stat = RD_REG_DWORD(®->u.isp2300.host_status); @@ -216,7 +218,7 @@ qla2300_intr_handler(int irq, void *dev_id) WRT_REG_WORD(®->hccr, HCCR_CLR_RISC_INT); RD_REG_WORD_RELAXED(®->hccr); } - spin_unlock(&ha->hardware_lock); + spin_unlock_irqrestore(&ha->hardware_lock, flags); if (test_bit(MBX_INTR_WAIT, &ha->mbx_cmd_flags) && (status & MBX_INTERRUPT) && ha->flags.mbox_int) { @@ -1626,6 +1628,7 @@ qla24xx_intr_handler(int irq, void *dev_id) uint32_t hccr; uint16_t mb[4]; struct rsp_que *rsp; + unsigned long flags; rsp = (struct rsp_que *) dev_id; if (!rsp) { @@ -1638,7 +1641,7 @@ qla24xx_intr_handler(int irq, void *dev_id) reg = &ha->iobase->isp24; status = 0; - spin_lock(&ha->hardware_lock); + spin_lock_irqsave(&ha->hardware_lock, flags); vha = pci_get_drvdata(ha->pdev); for (iter = 50; iter--; ) { stat = RD_REG_DWORD(®->host_status); @@ -1688,7 +1691,7 @@ qla24xx_intr_handler(int irq, void *dev_id) WRT_REG_DWORD(®->hccr, HCCRX_CLR_RISC_INT); RD_REG_DWORD_RELAXED(®->hccr); } - spin_unlock(&ha->hardware_lock); + spin_unlock_irqrestore(&ha->hardware_lock, flags); if (test_bit(MBX_INTR_WAIT, &ha->mbx_cmd_flags) && (status & MBX_INTERRUPT) && ha->flags.mbox_int) { -- 2.7.4