From 6e40de8b6b3cfa7288bb4a1fee2c7173f53b7345 Mon Sep 17 00:00:00 2001 From: Tyrel Datwyler Date: Thu, 2 May 2019 19:50:57 -0500 Subject: scsi: ibmvscsi: redo driver work thread to use enum action states The current implemenation relies on two flags in the driver's private host structure to signal the need for a host reset or to reenable the CRQ after a LPAR migration. This patch does away with those flags and introduces a single action flag and defined enums for the supported kthread work actions. Lastly, the if/else logic is replaced with a switch statement. Signed-off-by: Tyrel Datwyler Signed-off-by: Martin K. Petersen --- drivers/scsi/ibmvscsi/ibmvscsi.c | 61 +++++++++++++++++++++++++++------------- 1 file changed, 42 insertions(+), 19 deletions(-) (limited to 'drivers/scsi/ibmvscsi/ibmvscsi.c') diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c index 65fc8ca962c5..8df82c58e7b9 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -828,7 +828,7 @@ static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata) atomic_set(&hostdata->request_limit, 0); purge_requests(hostdata, DID_ERROR); - hostdata->reset_crq = 1; + hostdata->action = IBMVSCSI_HOST_ACTION_RESET; wake_up(&hostdata->work_wait_q); } @@ -1797,7 +1797,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq, /* We need to re-setup the interpartition connection */ dev_info(hostdata->dev, "Re-enabling adapter!\n"); hostdata->client_migrated = 1; - hostdata->reenable_crq = 1; + hostdata->action = IBMVSCSI_HOST_ACTION_REENABLE; purge_requests(hostdata, DID_REQUEUE); wake_up(&hostdata->work_wait_q); } else { @@ -2116,48 +2116,71 @@ static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev) static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata) { + unsigned long flags; int rc; char *action = "reset"; - if (hostdata->reset_crq) { - smp_rmb(); - hostdata->reset_crq = 0; - + spin_lock_irqsave(hostdata->host->host_lock, flags); + switch (hostdata->action) { + case IBMVSCSI_HOST_ACTION_NONE: + break; + case IBMVSCSI_HOST_ACTION_RESET: + spin_unlock_irqrestore(hostdata->host->host_lock, flags); rc = ibmvscsi_reset_crq_queue(&hostdata->queue, hostdata); + spin_lock_irqsave(hostdata->host->host_lock, flags); if (!rc) rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0); vio_enable_interrupts(to_vio_dev(hostdata->dev)); - } else if (hostdata->reenable_crq) { - smp_rmb(); + break; + case IBMVSCSI_HOST_ACTION_REENABLE: action = "enable"; + spin_unlock_irqrestore(hostdata->host->host_lock, flags); rc = ibmvscsi_reenable_crq_queue(&hostdata->queue, hostdata); - hostdata->reenable_crq = 0; + spin_lock_irqsave(hostdata->host->host_lock, flags); if (!rc) rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0); - } else - return; + break; + default: + break; + } + + hostdata->action = IBMVSCSI_HOST_ACTION_NONE; if (rc) { atomic_set(&hostdata->request_limit, -1); dev_err(hostdata->dev, "error after %s\n", action); } + spin_unlock_irqrestore(hostdata->host->host_lock, flags); scsi_unblock_requests(hostdata->host); } -static int ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata) +static int __ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata) { if (kthread_should_stop()) return 1; - else if (hostdata->reset_crq) { - smp_rmb(); - return 1; - } else if (hostdata->reenable_crq) { - smp_rmb(); - return 1; + switch (hostdata->action) { + case IBMVSCSI_HOST_ACTION_NONE: + return 0; + case IBMVSCSI_HOST_ACTION_RESET: + case IBMVSCSI_HOST_ACTION_REENABLE: + default: + break; } - return 0; + return 1; +} + +static int ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata) +{ + unsigned long flags; + int rc; + + spin_lock_irqsave(hostdata->host->host_lock, flags); + rc = __ibmvscsi_work_to_do(hostdata); + spin_unlock_irqrestore(hostdata->host->host_lock, flags); + + return rc; } static int ibmvscsi_work(void *data) -- cgit v1.2.3