arcmsr: fix command timeout under heavy load

This patch rewrites the interrupt service routine relate function to fix
a command timeout under heavy controller load.

Signed-off-by: Ching Huang <ching2048@areca.com.tw>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 97 insertions, 101 deletions

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index b13764ca23fd..506fe7b851bc 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -1441,14 +1441,15 @@ static void arcmsr_hba_doorbell_isr(struct AdapterControlBlock *acb)
         uint32_t outbound_doorbell;
         struct MessageUnit_A __iomem *reg = acb->pmuA;
         outbound_doorbell = readl(&reg->outbound_doorbell);
-        writel(outbound_doorbell, &reg->outbound_doorbell);
-        if (outbound_doorbell & ARCMSR_OUTBOUND_IOP331_DATA_WRITE_OK) {
-                arcmsr_iop2drv_data_wrote_handle(acb);
-        }
-
-        if (outbound_doorbell & ARCMSR_OUTBOUND_IOP331_DATA_READ_OK) {
-                arcmsr_iop2drv_data_read_handle(acb);
-        }
+        do {
+                writel(outbound_doorbell, &reg->outbound_doorbell);
+                if (outbound_doorbell & ARCMSR_OUTBOUND_IOP331_DATA_WRITE_OK)
+                        arcmsr_iop2drv_data_wrote_handle(acb);
+                if (outbound_doorbell & ARCMSR_OUTBOUND_IOP331_DATA_READ_OK)
+                        arcmsr_iop2drv_data_read_handle(acb);
+                outbound_doorbell = readl(&reg->outbound_doorbell);
+        } while (outbound_doorbell & (ARCMSR_OUTBOUND_IOP331_DATA_WRITE_OK
+                | ARCMSR_OUTBOUND_IOP331_DATA_READ_OK));
 }
 static void arcmsr_hbc_doorbell_isr(struct AdapterControlBlock *pACB)
 {
@@ -1462,17 +1463,19 @@ static void arcmsr_hbc_doorbell_isr(struct AdapterControlBlock *pACB)
         *******************************************************************
         */
         outbound_doorbell = readl(&reg->outbound_doorbell);
-        writel(outbound_doorbell, &reg->outbound_doorbell_clear);/*clear interrupt*/
-        if (outbound_doorbell & ARCMSR_HBCMU_IOP2DRV_DATA_WRITE_OK) {
-                arcmsr_iop2drv_data_wrote_handle(pACB);
-        }
-        if (outbound_doorbell & ARCMSR_HBCMU_IOP2DRV_DATA_READ_OK) {
-                arcmsr_iop2drv_data_read_handle(pACB);
-        }
-        if (outbound_doorbell & ARCMSR_HBCMU_IOP2DRV_MESSAGE_CMD_DONE) {
-                arcmsr_hbc_message_isr(pACB);    /* messenger of "driver to iop commands" */
-        }
-        return;
+        do {
+                writel(outbound_doorbell, &reg->outbound_doorbell_clear);
+                readl(&reg->outbound_doorbell_clear);
+                if (outbound_doorbell & ARCMSR_HBCMU_IOP2DRV_DATA_WRITE_OK)
+                        arcmsr_iop2drv_data_wrote_handle(pACB);
+                if (outbound_doorbell & ARCMSR_HBCMU_IOP2DRV_DATA_READ_OK)
+                        arcmsr_iop2drv_data_read_handle(pACB);
+                if (outbound_doorbell & ARCMSR_HBCMU_IOP2DRV_MESSAGE_CMD_DONE)
+                        arcmsr_hbc_message_isr(pACB);
+                outbound_doorbell = readl(&reg->outbound_doorbell);
+        } while (outbound_doorbell & (ARCMSR_HBCMU_IOP2DRV_DATA_WRITE_OK
+                | ARCMSR_HBCMU_IOP2DRV_DATA_READ_OK
+                | ARCMSR_HBCMU_IOP2DRV_MESSAGE_CMD_DONE));
 }
 static void arcmsr_hba_postqueue_isr(struct AdapterControlBlock *acb)
 {
@@ -1521,21 +1524,23 @@ static void arcmsr_hbc_postqueue_isr(struct AdapterControlBlock *acb)
         /* areca cdb command done */
         /* Use correct offset and size for syncing */
 
-        while (readl(&phbcmu->host_int_status) &
-        ARCMSR_HBCMU_OUTBOUND_POSTQUEUE_ISR){
-        /* check if command done with no error*/
-        flag_ccb = readl(&phbcmu->outbound_queueport_low);
-        ccb_cdb_phy = (flag_ccb & 0xFFFFFFF0);/*frame must be 32 bytes aligned*/
-        arcmsr_cdb = (struct ARCMSR_CDB *)(acb->vir2phy_offset + ccb_cdb_phy);
-        ccb = container_of(arcmsr_cdb, struct CommandControlBlock, arcmsr_cdb);
-        error = (flag_ccb & ARCMSR_CCBREPLY_FLAG_ERROR_MODE1) ? true : false;
-        /* check if command done with no error */
-        arcmsr_drain_donequeue(acb, ccb, error);
-        if (throttling == ARCMSR_HBC_ISR_THROTTLING_LEVEL) {
-                writel(ARCMSR_HBCMU_DRV2IOP_POSTQUEUE_THROTTLING, &phbcmu->inbound_doorbell);
-                break;
-        }
-        throttling++;
+        while ((flag_ccb = readl(&phbcmu->outbound_queueport_low)) !=
+                        0xFFFFFFFF) {
+                ccb_cdb_phy = (flag_ccb & 0xFFFFFFF0);
+                arcmsr_cdb = (struct ARCMSR_CDB *)(acb->vir2phy_offset
+                        + ccb_cdb_phy);
+                ccb = container_of(arcmsr_cdb, struct CommandControlBlock,
+                        arcmsr_cdb);
+                error = (flag_ccb & ARCMSR_CCBREPLY_FLAG_ERROR_MODE1)
+                        ? true : false;
+                /* check if command done with no error */
+                arcmsr_drain_donequeue(acb, ccb, error);
+                throttling++;
+                if (throttling == ARCMSR_HBC_ISR_THROTTLING_LEVEL) {
+                        writel(ARCMSR_HBCMU_DRV2IOP_POSTQUEUE_THROTTLING,
+                                &phbcmu->inbound_doorbell);
+                        throttling = 0;
+                }
         }
 }
 /*
@@ -1584,21 +1589,22 @@ static int arcmsr_handle_hba_isr(struct AdapterControlBlock *acb)
         struct MessageUnit_A __iomem *reg = acb->pmuA;
         outbound_intstatus = readl(&reg->outbound_intstatus) &
                 acb->outbound_int_enable;
-        if (!(outbound_intstatus & ARCMSR_MU_OUTBOUND_HANDLE_INT))      {
-                return 1;
-        }
-        writel(outbound_intstatus, &reg->outbound_intstatus);
-        if (outbound_intstatus & ARCMSR_MU_OUTBOUND_DOORBELL_INT)       {
-                arcmsr_hba_doorbell_isr(acb);
-        }
-        if (outbound_intstatus & ARCMSR_MU_OUTBOUND_POSTQUEUE_INT) {
-                arcmsr_hba_postqueue_isr(acb);
-        }
-        if(outbound_intstatus & ARCMSR_MU_OUTBOUND_MESSAGE0_INT)        {
-                /* messenger of "driver to iop commands" */
-                arcmsr_hba_message_isr(acb);
-        }
-        return 0;
+        if (!(outbound_intstatus & ARCMSR_MU_OUTBOUND_HANDLE_INT))
+                return IRQ_NONE;
+        do {
+                writel(outbound_intstatus, &reg->outbound_intstatus);
+                if (outbound_intstatus & ARCMSR_MU_OUTBOUND_DOORBELL_INT)
+                        arcmsr_hba_doorbell_isr(acb);
+                if (outbound_intstatus & ARCMSR_MU_OUTBOUND_POSTQUEUE_INT)
+                        arcmsr_hba_postqueue_isr(acb);
+                if (outbound_intstatus & ARCMSR_MU_OUTBOUND_MESSAGE0_INT)
+                        arcmsr_hba_message_isr(acb);
+                outbound_intstatus = readl(&reg->outbound_intstatus) &
+                        acb->outbound_int_enable;
+        } while (outbound_intstatus & (ARCMSR_MU_OUTBOUND_DOORBELL_INT
+                | ARCMSR_MU_OUTBOUND_POSTQUEUE_INT
+                | ARCMSR_MU_OUTBOUND_MESSAGE0_INT));
+        return IRQ_HANDLED;
 }
 
 static int arcmsr_handle_hbb_isr(struct AdapterControlBlock *acb)
@@ -1608,27 +1614,25 @@ static int arcmsr_handle_hbb_isr(struct AdapterControlBlock *acb)
         outbound_doorbell = readl(reg->iop2drv_doorbell) &
                                 acb->outbound_int_enable;
         if (!outbound_doorbell)
-                return 1;
-
-        writel(~outbound_doorbell, reg->iop2drv_doorbell);
-        /*in case the last action of doorbell interrupt clearance is cached,
-        this action can push HW to write down the clear bit*/
-        readl(reg->iop2drv_doorbell);
-        writel(ARCMSR_DRV2IOP_END_OF_INTERRUPT, reg->drv2iop_doorbell);
-        if (outbound_doorbell & ARCMSR_IOP2DRV_DATA_WRITE_OK) {
-                arcmsr_iop2drv_data_wrote_handle(acb);
-        }
-        if (outbound_doorbell & ARCMSR_IOP2DRV_DATA_READ_OK) {
-                arcmsr_iop2drv_data_read_handle(acb);
-        }
-        if (outbound_doorbell & ARCMSR_IOP2DRV_CDB_DONE) {
-                arcmsr_hbb_postqueue_isr(acb);
-        }
-        if(outbound_doorbell & ARCMSR_IOP2DRV_MESSAGE_CMD_DONE) {
-                /* messenger of "driver to iop commands" */
-                arcmsr_hbb_message_isr(acb);
-        }
-        return 0;
+                return IRQ_NONE;
+        do {
+                writel(~outbound_doorbell, reg->iop2drv_doorbell);
+                writel(ARCMSR_DRV2IOP_END_OF_INTERRUPT, reg->drv2iop_doorbell);
+                if (outbound_doorbell & ARCMSR_IOP2DRV_DATA_WRITE_OK)
+                        arcmsr_iop2drv_data_wrote_handle(acb);
+                if (outbound_doorbell & ARCMSR_IOP2DRV_DATA_READ_OK)
+                        arcmsr_iop2drv_data_read_handle(acb);
+                if (outbound_doorbell & ARCMSR_IOP2DRV_CDB_DONE)
+                        arcmsr_hbb_postqueue_isr(acb);
+                if (outbound_doorbell & ARCMSR_IOP2DRV_MESSAGE_CMD_DONE)
+                        arcmsr_hbb_message_isr(acb);
+                outbound_doorbell = readl(reg->iop2drv_doorbell) &
+                        acb->outbound_int_enable;
+        } while (outbound_doorbell & (ARCMSR_IOP2DRV_DATA_WRITE_OK
+                | ARCMSR_IOP2DRV_DATA_READ_OK
+                | ARCMSR_IOP2DRV_CDB_DONE
+                | ARCMSR_IOP2DRV_MESSAGE_CMD_DONE));
+        return IRQ_HANDLED;
 }
 
 static int arcmsr_handle_hbc_isr(struct AdapterControlBlock *pACB)
@@ -1640,44 +1644,36 @@ static int arcmsr_handle_hbc_isr(struct AdapterControlBlock *pACB)
         **   check outbound intstatus
         *********************************************
         */
-        host_interrupt_status = readl(&phbcmu->host_int_status);
-        if (!host_interrupt_status) {
-                /*it must be share irq*/
-                return 1;
-        }
-        /* MU ioctl transfer doorbell interrupts*/
-        if (host_interrupt_status & ARCMSR_HBCMU_OUTBOUND_DOORBELL_ISR) {
-                arcmsr_hbc_doorbell_isr(pACB);   /* messenger of "ioctl message read write" */
-        }
-        /* MU post queue interrupts*/
-        if (host_interrupt_status & ARCMSR_HBCMU_OUTBOUND_POSTQUEUE_ISR) {
-                arcmsr_hbc_postqueue_isr(pACB);  /* messenger of "scsi commands" */
-        }
-        return 0;
+        host_interrupt_status = readl(&phbcmu->host_int_status) &
+                (ARCMSR_HBCMU_OUTBOUND_POSTQUEUE_ISR |
+                ARCMSR_HBCMU_OUTBOUND_DOORBELL_ISR);
+        if (!host_interrupt_status)
+                return IRQ_NONE;
+        do {
+                if (host_interrupt_status & ARCMSR_HBCMU_OUTBOUND_DOORBELL_ISR)
+                        arcmsr_hbc_doorbell_isr(pACB);
+                /* MU post queue interrupts*/
+                if (host_interrupt_status & ARCMSR_HBCMU_OUTBOUND_POSTQUEUE_ISR)
+                        arcmsr_hbc_postqueue_isr(pACB);
+                host_interrupt_status = readl(&phbcmu->host_int_status);
+        } while (host_interrupt_status & (ARCMSR_HBCMU_OUTBOUND_POSTQUEUE_ISR |
+                ARCMSR_HBCMU_OUTBOUND_DOORBELL_ISR));
+        return IRQ_HANDLED;
 }
 static irqreturn_t arcmsr_interrupt(struct AdapterControlBlock *acb)
 {
         switch (acb->adapter_type) {
-        case ACB_ADAPTER_TYPE_A: {
-                if (arcmsr_handle_hba_isr(acb)) {
-                        return IRQ_NONE;
-                }
-                }
+        case ACB_ADAPTER_TYPE_A:
+                return arcmsr_handle_hba_isr(acb);
                 break;
-
-        case ACB_ADAPTER_TYPE_B: {
-                if (arcmsr_handle_hbb_isr(acb)) {
-                        return IRQ_NONE;
-                }
-                }
+        case ACB_ADAPTER_TYPE_B:
+                return arcmsr_handle_hbb_isr(acb);
                 break;
-         case ACB_ADAPTER_TYPE_C: {
-                if (arcmsr_handle_hbc_isr(acb)) {
-                        return IRQ_NONE;
-                }
-                }
+        case ACB_ADAPTER_TYPE_C:
+                return arcmsr_handle_hbc_isr(acb);
+        default:
+                return IRQ_NONE;
         }
-        return IRQ_HANDLED;
 }
 
 static void arcmsr_iop_parking(struct AdapterControlBlock *acb)