diff options
| author | Karen Higgins <karen.higgins@qlogic.com> | 2013-01-20 23:51:00 -0500 |
|---|---|---|
| committer | James Bottomley <JBottomley@Parallels.com> | 2013-01-30 13:47:16 +1100 |
| commit | 5b1c1bff07d579f8a7b672d4e5262d52eba5ef01 (patch) | |
| tree | 83b802ffe3e95af2c8e2ecfc1fc907143149f274 /drivers/scsi/qla4xxx/ql4_mbx.c | |
| parent | ff4108dce9e82acbde8e8b1899aaa4d91bf504b7 (diff) | |
| download | linux-5b1c1bff07d579f8a7b672d4e5262d52eba5ef01.tar.bz2 | |
[SCSI] qla4xxx: Throttle active IOCBs to firmware limits
Problem:
QLA4xxx firmware may assert if given more IOCBs than it can handle.
Solution:
The driver was updated to throttle the number of active IOCBs based
on the total number of IOCB buffers received from get_firmware_status
mbx_sts[2].
Signed-off-by: Karen Higgins <karen.higgins@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/qla4xxx/ql4_mbx.c')
| -rw-r--r-- | drivers/scsi/qla4xxx/ql4_mbx.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/drivers/scsi/qla4xxx/ql4_mbx.c b/drivers/scsi/qla4xxx/ql4_mbx.c index 1c57c227c808..81e738d61ec0 100644 --- a/drivers/scsi/qla4xxx/ql4_mbx.c +++ b/drivers/scsi/qla4xxx/ql4_mbx.c @@ -697,8 +697,24 @@ int qla4xxx_get_firmware_status(struct scsi_qla_host * ha) return QLA_ERROR; } - ql4_printk(KERN_INFO, ha, "%ld firmware IOCBs available (%d).\n", - ha->host_no, mbox_sts[2]); + /* High-water mark of IOCBs */ + ha->iocb_hiwat = mbox_sts[2]; + DEBUG2(ql4_printk(KERN_INFO, ha, + "%s: firmware IOCBs available = %d\n", __func__, + ha->iocb_hiwat)); + + if (ha->iocb_hiwat > IOCB_HIWAT_CUSHION) + ha->iocb_hiwat -= IOCB_HIWAT_CUSHION; + + /* Ideally, we should not enter this code, as the # of firmware + * IOCBs is hard-coded in the firmware. We set a default + * iocb_hiwat here just in case */ + if (ha->iocb_hiwat == 0) { + ha->iocb_hiwat = REQUEST_QUEUE_DEPTH / 4; + DEBUG2(ql4_printk(KERN_WARNING, ha, + "%s: Setting IOCB's to = %d\n", __func__, + ha->iocb_hiwat)); + } return QLA_SUCCESS; } |