[SCSI] advansys: Improve interrupt handler

Pass the Scsi_Host to the interrupt handler, rather than polling all
hosts for each interrupt.
Return IRQ_NONE if we didn't handle this interrupt
Don't set the IRQF_DISABLED flag; this is not a fast-executing interrupt
handler.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

diff --git a/drivers/scsi/advansys.c b/drivers/scsi/advansys.c
index 6d11076bbd0228e10cfa4d8ddd2fe1791c3c384a..a407ff34199d48b6890f27caac8fe12a922e5c0b 100644 (file)
--- a/drivers/scsi/advansys.c
+++ b/drivers/scsi/advansys.c
@@ -3951,7 +3951,6 @@ static PortAddr _asc_def_iop_base[];
  * advansys.h contains function prototypes for functions global to Linux.
  */
 
-static irqreturn_t advansys_interrupt(int, void *);
 static int advansys_slave_configure(struct scsi_device *);
 static void asc_scsi_done_list(struct scsi_cmnd *);
 static int asc_execute_scsi_cmnd(struct scsi_cmnd *);
@@ -4684,89 +4683,76 @@ static struct scsi_host_template driver_template = {
  */
 static irqreturn_t advansys_interrupt(int irq, void *dev_id)
 {
-       ulong flags;
-       int i;
-       asc_board_t *boardp;
+       unsigned long flags;
        struct scsi_cmnd *done_scp = NULL, *last_scp = NULL;
        struct scsi_cmnd *new_last_scp;
-       struct Scsi_Host *shost;
+       struct Scsi_Host *shost = dev_id;
+       asc_board_t *boardp = ASC_BOARDP(shost);
+       irqreturn_t result = IRQ_NONE;
 
-       ASC_DBG(1, "advansys_interrupt: begin\n");
+       ASC_DBG1(2, "advansys_interrupt: boardp 0x%p\n", boardp);
+       spin_lock_irqsave(&boardp->lock, flags);
+       if (ASC_NARROW_BOARD(boardp)) {
+               /*
+                * Narrow Board
+                */
+               if (AscIsIntPending(shost->io_port)) {
+                       result = IRQ_HANDLED;
+                       ASC_STATS(shost, interrupt);
+                       ASC_DBG(1, "advansys_interrupt: before AscISR()\n");
+                       AscISR(&boardp->dvc_var.asc_dvc_var);
+               }
+       } else {
+               /*
+                * Wide Board
+                */
+               ASC_DBG(1, "advansys_interrupt: before AdvISR()\n");
+               if (AdvISR(&boardp->dvc_var.adv_dvc_var)) {
+                       result = IRQ_HANDLED;
+                       ASC_STATS(shost, interrupt);
+               }
+       }
 
        /*
-        * Check for interrupts on all boards.
-        * AscISR() will call asc_isr_callback().
-        */
-       for (i = 0; i < asc_board_count; i++) {
-               shost = asc_host[i];
-               boardp = ASC_BOARDP(shost);
-               ASC_DBG2(2, "advansys_interrupt: i %d, boardp 0x%lx\n",
-                        i, (ulong)boardp);
-               spin_lock_irqsave(&boardp->lock, flags);
-               if (ASC_NARROW_BOARD(boardp)) {
-                       /*
-                        * Narrow Board
-                        */
-                       if (AscIsIntPending(shost->io_port)) {
-                               ASC_STATS(shost, interrupt);
-                               ASC_DBG(1,
-                                       "advansys_interrupt: before AscISR()\n");
-                               AscISR(&boardp->dvc_var.asc_dvc_var);
-                       }
-               } else {
-                       /*
-                        * Wide Board
-                        */
-                       ASC_DBG(1, "advansys_interrupt: before AdvISR()\n");
-                       if (AdvISR(&boardp->dvc_var.adv_dvc_var)) {
-                               ASC_STATS(shost, interrupt);
-                       }
+        * Start waiting requests and create a list of completed requests.
+        *
+        * If a reset request is being performed for the board, the reset
+        * handler will complete pending requests after it has completed.
+        */
+       if ((boardp->flags & ASC_HOST_IN_RESET) == 0) {
+               ASC_DBG2(1, "advansys_interrupt: done_scp 0x%p, "
+                        "last_scp 0x%p\n", done_scp, last_scp);
+
+               /* Start any waiting commands for the board. */
+               if (!ASC_QUEUE_EMPTY(&boardp->waiting)) {
+                       ASC_DBG(1, "advansys_interrupt: before "
+                               "asc_execute_queue()\n");
+                       asc_execute_queue(&boardp->waiting);
                }
 
                /*
-                * Start waiting requests and create a list of completed requests.
+                * Add to the list of requests that must be completed.
                 *
-                * If a reset request is being performed for the board, the reset
-                * handler will complete pending requests after it has completed.
+                * 'done_scp' will always be NULL on the first iteration of
+                * this loop. 'last_scp' is set at the same time as 'done_scp'.
                 */
-               if ((boardp->flags & ASC_HOST_IN_RESET) == 0) {
-                       ASC_DBG2(1,
-                                "advansys_interrupt: done_scp 0x%lx, last_scp 0x%lx\n",
-                                (ulong)done_scp, (ulong)last_scp);
-
-                       /* Start any waiting commands for the board. */
-                       if (!ASC_QUEUE_EMPTY(&boardp->waiting)) {
-                               ASC_DBG(1,
-                                       "advansys_interrupt: before asc_execute_queue()\n");
-                               asc_execute_queue(&boardp->waiting);
-                       }
-
-                       /*
-                        * Add to the list of requests that must be completed.
-                        *
-                        * 'done_scp' will always be NULL on the first iteration
-                        * of this loop. 'last_scp' is set at the same time as
-                        * 'done_scp'.
-                        */
-                       if (done_scp == NULL) {
-                               done_scp =
-                                   asc_dequeue_list(&boardp->done, &last_scp,
-                                                    ASC_TID_ALL);
-                       } else {
-                               ASC_ASSERT(last_scp != NULL);
-                               last_scp->host_scribble =
-                                   (unsigned char *)asc_dequeue_list(&boardp->
-                                                                     done,
-                                                                     &new_last_scp,
-                                                                     ASC_TID_ALL);
-                               if (new_last_scp != NULL) {
-                                       ASC_ASSERT(REQPNEXT(last_scp) != NULL);
-                                       last_scp = new_last_scp;
-                               }
+               if (done_scp == NULL) {
+                       done_scp = asc_dequeue_list(&boardp->done,
+                                               &last_scp, ASC_TID_ALL);
+               } else {
+                       ASC_ASSERT(last_scp != NULL);
+                       last_scp->host_scribble =
+                           (unsigned char *)asc_dequeue_list(&boardp->
+                                                             done,
+                                                             &new_last_scp,
+                                                             ASC_TID_ALL);
+                       if (new_last_scp != NULL) {
+                               ASC_ASSERT(REQPNEXT(last_scp) != NULL);
+                               last_scp = new_last_scp;
                        }
                }
-               spin_unlock_irqrestore(&boardp->lock, flags);
        }
+       spin_unlock_irqrestore(&boardp->lock, flags);
 
        /*
         * If interrupts were enabled on entry, then they
@@ -4778,7 +4764,7 @@ static irqreturn_t advansys_interrupt(int irq, void *dev_id)
        asc_scsi_done_list(done_scp);
 
        ASC_DBG(1, "advansys_interrupt: end\n");
-       return IRQ_HANDLED;
+       return result;
 }
 
 /*
@@ -17764,7 +17750,7 @@ advansys_board_found(int iop, struct device *dev, int bus_type)
        ASC_DVC_VAR *asc_dvc_varp = NULL;
        ADV_DVC_VAR *adv_dvc_varp = NULL;
        adv_sgblk_t *sgp = NULL;
-       int share_irq = FALSE;
+       int share_irq;
        int iolen = 0;
        ADV_PADDR pci_memory_address;
        int warn_code, err_code;
@@ -17918,15 +17904,15 @@ advansys_board_found(int iop, struct device *dev, int bus_type)
 #ifdef CONFIG_ISA
                case ASC_IS_ISA:
                        shost->unchecked_isa_dma = TRUE;
-                       share_irq = FALSE;
+                       share_irq = 0;
                        break;
                case ASC_IS_VL:
                        shost->unchecked_isa_dma = FALSE;
-                       share_irq = FALSE;
+                       share_irq = 0;
                        break;
                case ASC_IS_EISA:
                        shost->unchecked_isa_dma = FALSE;
-                       share_irq = TRUE;
+                       share_irq = IRQF_SHARED;
                        break;
 #endif /* CONFIG_ISA */
 #ifdef CONFIG_PCI
@@ -17937,7 +17923,7 @@ advansys_board_found(int iop, struct device *dev, int bus_type)
                                         PCI_SLOT(pdev->devfn),
                                         PCI_FUNC(pdev->devfn));
                        shost->unchecked_isa_dma = FALSE;
-                       share_irq = TRUE;
+                       share_irq = IRQF_SHARED;
                        break;
 #endif /* CONFIG_PCI */
                default:
@@ -17945,7 +17931,7 @@ advansys_board_found(int iop, struct device *dev, int bus_type)
                            ("advansys_board_found: board %d: unknown adapter type: %d\n",
                             boardp->id, asc_dvc_varp->bus_type);
                        shost->unchecked_isa_dma = TRUE;
-                       share_irq = FALSE;
+                       share_irq = 0;
                        break;
                }
        } else {
@@ -17961,7 +17947,7 @@ advansys_board_found(int iop, struct device *dev, int bus_type)
                                 PCI_SLOT(pdev->devfn),
                                 PCI_FUNC(pdev->devfn));
                shost->unchecked_isa_dma = FALSE;
-               share_irq = TRUE;
+               share_irq = IRQF_SHARED;
 #endif /* CONFIG_PCI */
        }
 
@@ -18425,25 +18411,11 @@ advansys_board_found(int iop, struct device *dev, int bus_type)
 
        /* Register IRQ Number. */
        ASC_DBG1(2, "advansys_board_found: request_irq() %d\n", shost->irq);
-       /*
-        * If request_irq() fails with the IRQF_DISABLED flag set,
-        * then try again without the IRQF_DISABLED flag set. This
-        * allows IRQ sharing to work even with other drivers that
-        * do not set the IRQF_DISABLED flag.
-        *
-        * If IRQF_DISABLED is not set, then interrupts are enabled
-        * before the driver interrupt function is called.
-        */
-       if (((ret = request_irq(shost->irq, advansys_interrupt,
-                               IRQF_DISABLED | (share_irq ==
-                                                TRUE ?
-                                                IRQF_SHARED :
-                                                0), "advansys", boardp)) != 0)
-           &&
-           ((ret =
-             request_irq(shost->irq, advansys_interrupt,
-                         (share_irq == TRUE ? IRQF_SHARED : 0),
-                         "advansys", boardp)) != 0)) {
+
+       ret = request_irq(shost->irq, advansys_interrupt, share_irq,
+                         "advansys", shost);
+
+       if (ret) {
                if (ret == -EBUSY) {
                        ASC_PRINT2
                            ("advansys_board_found: board %d: request_irq(): IRQ 0x%x already in use.\n",
@@ -18644,7 +18616,7 @@ advansys_board_found(int iop, struct device *dev, int bus_type)
 #ifdef CONFIG_PROC_FS
                kfree(boardp->prtbuf);
 #endif /* CONFIG_PROC_FS */
-               free_irq(shost->irq, boardp);
+               free_irq(shost->irq, shost);
                scsi_unregister(shost);
                asc_board_count--;
                return NULL;
@@ -18960,7 +18932,7 @@ static int advansys_release(struct Scsi_Host *shost)
 
        ASC_DBG(1, "advansys_release: begin\n");
        boardp = ASC_BOARDP(shost);
-       free_irq(shost->irq, boardp);
+       free_irq(shost->irq, shost);
        if (shost->dma_channel != NO_ISA_DMA) {
                ASC_DBG(1, "advansys_release: free_dma()\n");
                free_dma(shost->dma_channel);