On Wed, Jun 21, 2017 at 01:48:43PM -0700, Madhani, Himanshu wrote:
[...]
> + wait_queue_head_t nvme_ls_waitQ;
Can you please lower-case the 'Q' in waitQ IFF you have to re-send the series?
[...]
> + wait_queue_head_t nvme_waitQ;
Ditto
[...]
> + wait_queue_head_t nvme_waitQ;
And here as well.
> diff --git a/drivers/scsi/qla2xxx/qla_gbl.h b/drivers/scsi/qla2xxx/qla_gbl.h
> index 6fbee11c1a18..c6af45f7d5d6 100644
> --- a/drivers/scsi/qla2xxx/qla_gbl.h
> +++ b/drivers/scsi/qla2xxx/qla_gbl.h
> @@ -10,6 +10,16 @@
> #include <linux/interrupt.h>
>
> /*
> + * Global functions prototype in qla_nvme.c source file.
> + */
> +extern void qla_nvme_register_hba(scsi_qla_host_t *);
> +extern int qla_nvme_register_remote(scsi_qla_host_t *, fc_port_t *);
> +extern void qla_nvme_delete(scsi_qla_host_t *);
> +extern void qla_nvme_abort(struct qla_hw_data *, srb_t *sp);
> +extern void qla24xx_nvme_ls4_iocb(scsi_qla_host_t *, struct pt_ls4_request *,
> + struct req_que *);
You're still not convinced of the idea of headers, heh ;-)
Especially as you have a qla_nvme.h.
[...]
> + INIT_WORK(&fcport->nvme_del_work, qla_nvme_unregister_remote_port);
> + rport = kzalloc(sizeof(*rport), GFP_KERNEL);
> + if (!rport) {
> + ql_log(ql_log_warn, vha, 0x2101,
> + "%s: unable to alloc memory\n", __func__);
kzalloc() will warn you about a failed allocation, no need to double it.
See also:
http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdf
[...]
> + ret = nvme_fc_register_remoteport(vha->nvme_local_port, &rport->req,
> + &fcport->nvme_remote_port);
> + if (ret) {
> + ql_log(ql_log_warn, vha, 0x212e,
> + "Failed to register remote port. Transport returned %d\n",
> + ret);
> + return ret;
> + }
> +
> + fcport->nvme_remote_port->private = fcport;
I think I already said that in the last review, but can you please move the
fcport->nvme_remote_port->private = fcport;
assingment _above_ the nvme_fc_register_remoteport() call.
[...]
> + vha = (struct scsi_qla_host *)lport->private;
No need to cast from void *
> + ql_log(ql_log_info, vha, 0x2104,
> + "%s: handle %p, idx =%d, qsize %d\n",
> + __func__, handle, qidx, qsize);
Btw, sometime in the future you could change your ql_log() thingies to the
kernel's dyndebug facility.
[...]
> + rval = ha->isp_ops->abort_command(sp);
> + if (rval != QLA_SUCCESS)
> + ql_log(ql_log_warn, fcport->vha, 0x2125,
> + "%s: failed to abort LS command for SP:%p rval=%x\n",
> + __func__, sp, rval);
> +
> + ql_dbg(ql_dbg_io, fcport->vha, 0x212b,
> + "%s: aborted sp:%p on fcport:%p\n", __func__, sp, fcport);
If you insinst in having these two messages ("failed to abort" and "aborted")
can you at least fold it into one print statement.
> + rval = ha->isp_ops->abort_command(sp);
> + if (!rval)
> + ql_log(ql_log_warn, fcport->vha, 0x2127,
> + "%s: failed to abort command for SP:%p rval=%x\n",
> + __func__, sp, rval);
> +
> + ql_dbg(ql_dbg_io, fcport->vha, 0x2126,
> + "%s: aborted sp:%p on fcport:%p\n", __func__, sp, fcport);
Ditto.
[...]
> + /* Setup qpair pointers */
> + req = qpair->req;
> + tot_dsds = fd->sg_cnt;
> +
> + /* Acquire qpair specific lock */
> + spin_lock_irqsave(&qpair->qp_lock, flags);
> +
> + /* Check for room in outstanding command list. */
> + handle = req->current_outstanding_cmd;
I've just seen this in qla2xxx_start_scsi_mq() and
qla2xxx_dif_start_scsi_mq() and was about to send you an RFC patch. But
here it is for completeness in the nvme version as well:
You save a pointer to the req_que from you qpair and _afterwards_ you grab
the qp_lock. What prevents someone from changing the request internals
underneath you?
Like this:
CPU0 CPU1
req = qpair->req;
qla2xxx_delete_qpair(vha, qpair);
`-> ret = qla25xx_delete_req_que(vha, qpair->req);
spin_lock_irqsave(&qpair->qp_lock, flags);
handle = req->current_outstanding_cmd;
Oh and btw, neither qla2xxx_delete_qpair() nor qla25xx_delete_req_que() grab
the qp_lock.
I think this is something work re-thinking. Maybe you can identify the blocks
accessing struct members which need to be touched under a lock and extract
them into a helper function wich calls lockdep_assert_held(). No must just and
idea.
[...]
> +
> + /* Load data segments */
> + for_each_sg(sgl, sg, tot_dsds, i) {
Do you really need the whole loop under a spin_lock_irqsave()? If the sglist
has a lot of entries (i.e. becasue we couldn't cluster it) we're in risk to
trigger a NMI watchdog soft-lockup WARN_ON(). You need to grab the lock when
accessing req's members but the rest of the loop? This applies to
qla24xx_build_scsi_iocbs() for SCSI as well.
[...]
> + struct qla_qpair *qpair = (struct qla_qpair *)hw_queue_handle;
Void pointer cast. Someone really should write a coccinelle script to get rid
of 'em.
[...]
> + /* Alloc SRB structure */
> + sp = qla2xxx_get_qpair_sp(qpair, fcport, GFP_ATOMIC);
> + if (!sp)
> + return -EIO;
__blk_mq_run_hw_queue()
`-> blk_mq_sched_dispatch_requests()
`-> blk_mq_dispatch_rq_list()
`-> nvme_fc_queue_rq()
`-> nvme_fc_start_fcp_op()
`-> qla_nvme_post_cmd()
isn't called from an IRQ context and qla2xxx_get_qpair_sp() internally
uses mempool_alloc(). From mempool_alloc()'s documentation:
"Note that due to preallocation, this function *never* fails when called from
process contexts. (it might fail if called from an IRQ context.)"
mm/mempool.c:306
[...]
> + fcport = (fc_port_t *)rport->private;
Void cast.
[...]
> + rval = ha->isp_ops->abort_command(sp);
> + if (!rval) {
> + if (!qla_nvme_wait_on_command(sp))
if (!rval && !qla_nvme_wait_on_command(sp))
[...]
> + for (cnt = 1; cnt < req->num_outstanding_cmds; cnt++) {
> + sp = req->outstanding_cmds[cnt];
> + if ((sp) && ((sp->type == SRB_NVME_CMD) ||
^ parenthesis
> + (sp->type == SRB_NVME_LS)) &&
> + (sp->fcport == fcport)) {
^ parenthesis
[...]
> diff --git a/drivers/scsi/qla2xxx/qla_nvme.h b/drivers/scsi/qla2xxx/qla_nvme.h
[...]
void qla_nvme_register_hba(scsi_qla_host_t *);
int qla_nvme_register_remote(scsi_qla_host_t *, fc_port_t *);
void qla_nvme_delete(scsi_qla_host_t *);
void qla_nvme_abort(struct qla_hw_data *, srb_t *sp);
void qla24xx_nvme_ls4_iocb(scsi_qla_host_t *, struct pt_ls4_request *, struct req_que *);
[...]
> +#if (IS_ENABLED(CONFIG_NVME_FC))
> +int ql2xnvmeenable = 1;
> +#else
> +int ql2xnvmeenable;
> +#endif
> +module_param(ql2xnvmeenable, int, 0644);
> +MODULE_PARM_DESC(ql2xnvmeenable,
> + "Enables NVME support. "
> + "0 - no NVMe. Default is Y");
Default is Y IFF CONFIG_NVME_FC is enabled. Is it possible to guard the whole module
paraneter with IS_ENABLED(CONFIG_NVME_FC)? Not sure if this would break if
CONFIG_NVME_FC=n and someone does qla2xxx.ql2xnvmeenable=N.
[...]
> - if (sp->type != SRB_NVME_CMD) {
> + if ((sp->type != SRB_NVME_CMD) && (sp->type != SRB_NVME_LS)) {
http://en.cppreference.com/w/c/language/operator_precedence
> + if ((sp->type == SRB_NVME_CMD) ||
> + (sp->type == SRB_NVME_LS)) {
^^
Thanks,
Johannes
--
Johannes Thumshirn Storage
jthumshirn@xxxxxxx +49 911 74053 689
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