diff options
| author | Quinn Tran <qutran@marvell.com> | 2020-09-04 06:51:26 +0200 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2020-09-23 00:42:49 +0200 |
| commit | 89c72f4245a8510ffdb0d1980944210b8bc6e49f (patch) | |
| tree | b81139c7985687e4aa13cba9d4e81114e61a97ab /drivers/scsi/qla2xxx/qla_dfs.c | |
| parent | scsi: qla2xxx: Add rport fields in debugfs (diff) | |
| download | linux-89c72f4245a8510ffdb0d1980944210b8bc6e49f.tar.xz linux-89c72f4245a8510ffdb0d1980944210b8bc6e49f.zip | |
scsi: qla2xxx: Add IOCB resource tracking
This patch tracks number of IOCB resources used in the I/O fast path. If
the number of used IOCBs reach a high water limit, driver would return the
I/O as busy and let upper layer retry. This prevents over subscription of
IOCB resources where any future error recovery command is unable to cut
through. Enable IOCB throttling by default.
Link: https://lore.kernel.org/r/20200904045128.23631-12-njavali@marvell.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/qla2xxx/qla_dfs.c')
| -rw-r--r-- | drivers/scsi/qla2xxx/qla_dfs.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/scsi/qla2xxx/qla_dfs.c b/drivers/scsi/qla2xxx/qla_dfs.c index 118f2b223531..6f5f18fc974a 100644 --- a/drivers/scsi/qla2xxx/qla_dfs.c +++ b/drivers/scsi/qla2xxx/qla_dfs.c @@ -261,6 +261,8 @@ qla_dfs_fw_resource_cnt_show(struct seq_file *s, void *unused) struct scsi_qla_host *vha = s->private; uint16_t mb[MAX_IOCB_MB_REG]; int rc; + struct qla_hw_data *ha = vha->hw; + u16 iocbs_used, i; rc = qla24xx_res_count_wait(vha, mb, SIZEOF_IOCB_MB_REG); if (rc != QLA_SUCCESS) { @@ -285,6 +287,18 @@ qla_dfs_fw_resource_cnt_show(struct seq_file *s, void *unused) mb[23]); } + if (ql2xenforce_iocb_limit) { + /* lock is not require. It's an estimate. */ + iocbs_used = ha->base_qpair->fwres.iocbs_used; + for (i = 0; i < ha->max_qpairs; i++) { + if (ha->queue_pair_map[i]) + iocbs_used += ha->queue_pair_map[i]->fwres.iocbs_used; + } + + seq_printf(s, "Driver: estimate iocb used [%d] high water limit [%d]\n", + iocbs_used, ha->base_qpair->fwres.iocbs_limit); + } + return 0; } |