[SCSI] ibmvfc: Fix dropped interrupts

This patch fixes a problem of possible dropped interrupts. Currently,
the ibmvfc driver has a race condition where after ibmvfc_interrupt
gets run, the platform code clears the interrupt. This can result in
lost interrupts and, in worst case scenarios, result in command
timeouts. Fix this by implementing a tasklet similar to what the
ibmvscsi driver does so that interrupt processing is no longer done in
the actual interrupt handler, which eliminates the race.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h
index b21e071b9862..70107522e3a9 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.h
+++ b/drivers/scsi/ibmvscsi/ibmvfc.h
@@ -684,6 +684,7 @@ struct ibmvfc_host {
         char partition_name[97];
         void (*job_step) (struct ibmvfc_host *);
         struct task_struct *work_thread;
+        struct tasklet_struct tasklet;
         wait_queue_head_t init_wait_q;
         wait_queue_head_t work_wait_q;
 };