[SCSI] ipr: Reduce interrupt lock time

Reduce the amount of time the host lock is held in the interrupt handler
for improved performance.

[jejb: fix up checkpatch noise]
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index b2994e2cf01762181bcb5e4b1d209b95ce7a4b14..07b14ba6906ab53578fc5c1a28d2b0464ec68b83 100644 (file)
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -565,6 +565,23 @@ static void ipr_trc_hook(struct ipr_cmnd *ipr_cmd,
 #define ipr_trc_hook(ipr_cmd, type, add_data) do { } while(0)
 #endif
 
+/**
+ * ipr_lock_and_done - Acquire lock and complete command
+ * @ipr_cmd:   ipr command struct
+ *
+ * Return value:
+ *     none
+ **/
+static void ipr_lock_and_done(struct ipr_cmnd *ipr_cmd)
+{
+       unsigned long lock_flags;
+       struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;
+
+       spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);
+       ipr_cmd->done(ipr_cmd);
+       spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
+}
+
 /**
  * ipr_reinit_ipr_cmnd - Re-initialize an IPR Cmnd block for reuse
  * @ipr_cmd:   ipr command struct
@@ -611,11 +628,13 @@ static void ipr_reinit_ipr_cmnd(struct ipr_cmnd *ipr_cmd)
  * Return value:
  *     none
  **/
-static void ipr_init_ipr_cmnd(struct ipr_cmnd *ipr_cmd)
+static void ipr_init_ipr_cmnd(struct ipr_cmnd *ipr_cmd,
+                             void (*fast_done) (struct ipr_cmnd *))
 {
        ipr_reinit_ipr_cmnd(ipr_cmd);
        ipr_cmd->u.scratch = 0;
        ipr_cmd->sibling = NULL;
+       ipr_cmd->fast_done = fast_done;
        init_timer(&ipr_cmd->timer);
 }
 
@@ -648,7 +667,7 @@ static
 struct ipr_cmnd *ipr_get_free_ipr_cmnd(struct ipr_ioa_cfg *ioa_cfg)
 {
        struct ipr_cmnd *ipr_cmd = __ipr_get_free_ipr_cmnd(ioa_cfg);
-       ipr_init_ipr_cmnd(ipr_cmd);
+       ipr_init_ipr_cmnd(ipr_cmd, ipr_lock_and_done);
        return ipr_cmd;
 }
 
@@ -5130,8 +5149,9 @@ static irqreturn_t ipr_isr(int irq, void *devp)
        u16 cmd_index;
        int num_hrrq = 0;
        int irq_none = 0;
-       struct ipr_cmnd *ipr_cmd;
+       struct ipr_cmnd *ipr_cmd, *temp;
        irqreturn_t rc = IRQ_NONE;
+       LIST_HEAD(doneq);
 
        spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);
 
@@ -5152,8 +5172,8 @@ static irqreturn_t ipr_isr(int irq, void *devp)
 
                        if (unlikely(cmd_index >= IPR_NUM_CMD_BLKS)) {
                                ipr_isr_eh(ioa_cfg, "Invalid response handle from IOA");
-                               spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
-                               return IRQ_HANDLED;
+                               rc = IRQ_HANDLED;
+                               goto unlock_out;
                        }
 
                        ipr_cmd = ioa_cfg->ipr_cmnd_list[cmd_index];
@@ -5162,9 +5182,7 @@ static irqreturn_t ipr_isr(int irq, void *devp)
 
                        ipr_trc_hook(ipr_cmd, IPR_TRACE_FINISH, ioasc);
 
-                       list_del(&ipr_cmd->queue);
-                       del_timer(&ipr_cmd->timer);
-                       ipr_cmd->done(ipr_cmd);
+                       list_move_tail(&ipr_cmd->queue, &doneq);
 
                        rc = IRQ_HANDLED;
 
@@ -5194,8 +5212,8 @@ static irqreturn_t ipr_isr(int irq, void *devp)
                } else if (num_hrrq == IPR_MAX_HRRQ_RETRIES &&
                           int_reg & IPR_PCII_HRRQ_UPDATED) {
                        ipr_isr_eh(ioa_cfg, "Error clearing HRRQ");
-                       spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
-                       return IRQ_HANDLED;
+                       rc = IRQ_HANDLED;
+                       goto unlock_out;
                } else
                        break;
        }
@@ -5203,7 +5221,14 @@ static irqreturn_t ipr_isr(int irq, void *devp)
        if (unlikely(rc == IRQ_NONE))
                rc = ipr_handle_other_interrupt(ioa_cfg, int_reg);
 
+unlock_out:
        spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
+       list_for_each_entry_safe(ipr_cmd, temp, &doneq, queue) {
+               list_del(&ipr_cmd->queue);
+               del_timer(&ipr_cmd->timer);
+               ipr_cmd->fast_done(ipr_cmd);
+       }
+
        return rc;
 }
 
@@ -5784,15 +5809,22 @@ static void ipr_scsi_done(struct ipr_cmnd *ipr_cmd)
        struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;
        struct scsi_cmnd *scsi_cmd = ipr_cmd->scsi_cmd;
        u32 ioasc = be32_to_cpu(ipr_cmd->s.ioasa.hdr.ioasc);
+       unsigned long lock_flags;
 
        scsi_set_resid(scsi_cmd, be32_to_cpu(ipr_cmd->s.ioasa.hdr.residual_data_len));
 
        if (likely(IPR_IOASC_SENSE_KEY(ioasc) == 0)) {
-               scsi_dma_unmap(ipr_cmd->scsi_cmd);
+               scsi_dma_unmap(scsi_cmd);
+
+               spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);
                list_add_tail(&ipr_cmd->queue, &ioa_cfg->free_q);
                scsi_cmd->scsi_done(scsi_cmd);
-       } else
+               spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
+       } else {
+               spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);
                ipr_erp_start(ioa_cfg, ipr_cmd);
+               spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
+       }
 }
 
 /**
@@ -5848,12 +5880,12 @@ static int ipr_queuecommand(struct Scsi_Host *shost,
        ipr_cmd = __ipr_get_free_ipr_cmnd(ioa_cfg);
        spin_unlock_irqrestore(shost->host_lock, lock_flags);
 
-       ipr_init_ipr_cmnd(ipr_cmd);
+       ipr_init_ipr_cmnd(ipr_cmd, ipr_scsi_done);
        ioarcb = &ipr_cmd->ioarcb;
 
        memcpy(ioarcb->cmd_pkt.cdb, scsi_cmd->cmnd, scsi_cmd->cmd_len);
        ipr_cmd->scsi_cmd = scsi_cmd;
-       ipr_cmd->done = ipr_scsi_done;
+       ipr_cmd->done = ipr_scsi_eh_done;
 
        if (ipr_is_gscsi(res) || ipr_is_vset_device(res)) {
                if (scsi_cmd->underflow == 0)

diff --git a/drivers/scsi/ipr.h b/drivers/scsi/ipr.h
index 153b8bd91d1ef825952ec70fec861fea0e8d5fea..f69e4b385b9ad20b3a322794f840c0bcf845e68c 100644 (file)
--- a/drivers/scsi/ipr.h
+++ b/drivers/scsi/ipr.h
@@ -1525,6 +1525,7 @@ struct ipr_cmnd {
        struct ata_queued_cmd *qc;
        struct completion completion;
        struct timer_list timer;
+       void (*fast_done) (struct ipr_cmnd *);
        void (*done) (struct ipr_cmnd *);
        int (*job_step) (struct ipr_cmnd *);
        int (*job_step_failed) (struct ipr_cmnd *);