scsi: lpfc: Beef up stat counters for debug

If log verbose in not turned on, its hard to tell when certain error
paths get hit. Add stats counters and corresponding logic to
debugfs/sysfs to aid und

scsi: lpfc: Beef up stat counters for debug

If log verbose in not turned on, its hard to tell when certain error
paths get hit. Add stats counters and corresponding logic to
debugfs/sysfs to aid understanding what paths were traversed.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: Increase SCSI CQ and WQ sizes.

Increased the sizes of the SCSI WQ's and CQ's so that SCSI operation is
similar to that used by NVME. However, size increase restricted only to
those newer

scsi: lpfc: Increase SCSI CQ and WQ sizes.

Increased the sizes of the SCSI WQ's and CQ's so that SCSI operation is
similar to that used by NVME. However, size increase restricted only to
those newer adapters that can support the larger WQE size, thus bigger
queue sizes.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: Fix random heartbeat timeouts during heavy IO

NVME targets appear to randomly disconnect from the initiator when
running heavy IO.

The error is due to the host aggregate (across all con

scsi: lpfc: Fix random heartbeat timeouts during heavy IO

NVME targets appear to randomly disconnect from the initiator when
running heavy IO.

The error is due to the host aggregate (across all controllers) io load
was beyond the maximum exchange count for nvme on the adapter. The
driver was properly returning a resource busy status, but the io load
was so great heartbeat commands would be bounced and not have a
successful retry within the fuzz amount for the nvme heartbeat (yes, a
very high io load!). Thus the target was terminating the controller due
to a keep alive failure.

Resolve by reserving a few exchanges (by counters) which can be used
when the adapter is out of normal exchanges and the command is a NVME
heartbeat command. As counters are used, while the reserved command is
outstanding, as soon as any other exchange completes, the counters are
adjusted and the reserved count is replenished. The heartbeat completes
execution in a normal fashion.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: Correct driver deregistrations with host nvme transport

The driver's interaction with the host nvme transport has been incorrect
for a while. The driver did not wait for the unregister c

scsi: lpfc: Correct driver deregistrations with host nvme transport

The driver's interaction with the host nvme transport has been incorrect
for a while. The driver did not wait for the unregister callbacks
(waited only 5 jiffies). Thus the driver may remove objects that may be
referenced by subsequent abort commands from the transport, and the
actual unregister callback was effectively a noop. This was especially
problematic if the driver was unloaded.

The driver now waits for the unregister callbacks, as it should, before
continuing with teardown.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: Expand WQE capability of every NVME hardware queue

Hardware queues are a fast staging area to push commands into the
adapter. The adapter should drain them extremely quickly. However,
u

scsi: lpfc: Expand WQE capability of every NVME hardware queue

Hardware queues are a fast staging area to push commands into the
adapter. The adapter should drain them extremely quickly. However,
under heavy io load, the host cpu is pushing commands faster than the
drain rate of the adapter causing the driver to resource busy commands.

Enlarge the hardware queue (wq & cq) to support a larger number of queue
entries (4x the prior size) before backpressure. Enlarging the queue
requires larger contiguous buffers (16k) per logical page for the
hardware. This changed calling sequences that were expecting 4K page
sizes that now must pass a parameter with the page sizes. It also
required use of a new version of an adapter command that can vary the
page size values.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: Fix transition nvme-i rport handling to nport only.

As the devloss API was implemented in the nvmei driver, an evaluation of
the nvme transport and the lpfc driver showed dual management

scsi: lpfc: Fix transition nvme-i rport handling to nport only.

As the devloss API was implemented in the nvmei driver, an evaluation of
the nvme transport and the lpfc driver showed dual management of the
rports. This creates a bug possibility when the thread count and SAN
size increases.

The nvmei driver code was based on a very early transport and was not
revisited until the devloss API was introduced.

Remove the listhead in the driver's rport data structure and the
listhead in the driver's lport data structure. Remove all rport_list
traversal. Convert the driver to use the nrport (nvme rport) pointer
that is now NULL or nonNULL depending on a devloss action. Convert
debugfs and nvme_info in sysfs to use the fc_nodes list in the vport.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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lpfc: Fix memory corruption of the lpfc_ncmd->list pointers

lpfc was changing the private pointer that is set/maintained by
the nvme_fc transport. This caused two issues: a) the transport, on
teardo

lpfc: Fix memory corruption of the lpfc_ncmd->list pointers

lpfc was changing the private pointer that is set/maintained by
the nvme_fc transport. This caused two issues: a) the transport, on
teardown may erroneous attempt to free whatever address was set;
and b) lfpc uses any value set in lpfc_nvme_fcp_abort() and
assumes its a valid io request.

Correct issue by properly defining a context structure for lpfc.
Lpfc also updated to clear the private context structure on io
completion.

Since this bug caused scrutiny of the way lpfc moves local request
structures between lists, also cleaned up list_del()'s to
list_del_inits()'s.

This is a nvme-specific bug. The patch was cut against the
linux-block tree, for-4.12/block tree. It should be pulled in through
that tree.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

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Remove unused defines for NVME PostBuf.

These defines for the posting of buffers for nvmet target were not used.

Removing the unused defines.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com

Remove unused defines for NVME PostBuf.

These defines for the posting of buffers for nvmet target were not used.

Removing the unused defines.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

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Standardize nvme SGL segment count

Standardize default SGL segment count for nvme target and initiator

The driver needs to make them the same for clarity.

Signed-off-by: Dick Kennedy <dick.kennedy

Standardize nvme SGL segment count

Standardize default SGL segment count for nvme target and initiator

The driver needs to make them the same for clarity.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

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scsi: lpfc: add NVME exchange aborts

previous code did little more than log a message.

This patch adds abort path support, modeled after the SCSI code paths.
Currently addresses only the initiator

scsi: lpfc: add NVME exchange aborts

previous code did little more than log a message.

This patch adds abort path support, modeled after the SCSI code paths.
Currently addresses only the initiator path. Target path under
development, but stubbed out.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: Update copyrights

Update copyrights to 2017 for all files touched in this patch set

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broad

scsi: lpfc: Update copyrights

Update copyrights to 2017 for all files touched in this patch set

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

scsi: lpfc: NVME Initiator: Add debugfs support

NVME Initiator: Add debugfs support

Adds debugfs snippets to cover the new NVME initiator functionality

Signed-off-by: Dick Kennedy <dick.kennedy@br

scsi: lpfc: NVME Initiator: Add debugfs support

NVME Initiator: Add debugfs support

Adds debugfs snippets to cover the new NVME initiator functionality

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: NVME Initiator: bind to nvme_fc api

NVME Initiator: Tie in to NVME Fabrics nvme_fc LLDD initiator api

Adds the routines to:
- register and deregister the FC port as a nvme-fc initiator

scsi: lpfc: NVME Initiator: bind to nvme_fc api

NVME Initiator: Tie in to NVME Fabrics nvme_fc LLDD initiator api

Adds the routines to:
- register and deregister the FC port as a nvme-fc initiator localport
- register and deregister remote FC ports as a nvme-fc remoteport
- binding of nvme queues to adapter WQs
- send/perform NVME LS's
- send/perform NVME FCP initiator io operations

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

scsi: lpfc: NVME Initiator: Base modifications

NVME Initiator: Base modifications

This patch adds base modifications for NVME initiator support.

The base modifications consist of:
- Formal split o

scsi: lpfc: NVME Initiator: Base modifications

NVME Initiator: Base modifications

This patch adds base modifications for NVME initiator support.

The base modifications consist of:
- Formal split of SLI3 rings from SLI-4 WQs (sometimes referred to as
rings as well) as implementation now widely varies between the two.
- Addition of configuration modes:
SCSI initiator only; NVME initiator only; NVME target only; and
SCSI and NVME initiator.
The configuration mode drives overall adapter configuration,
offloads enabled, and resource splits.
NVME support is only available on SLI-4 devices and newer fw.
- Implements the following based on configuration mode:
- Exchange resources are split by protocol; Obviously, if only
1 mode, then no split occurs. Default is 50/50. module attribute
allows tuning.
- Pools and config parameters are separated per-protocol
- Each protocol has it's own set of queues, but share interrupt
vectors.
SCSI:
SLI3 devices have few queues and the original style of queue
allocation remains.
SLI4 devices piggy back on an "io-channel" concept that
eventually needs to merge with scsi-mq/blk-mq support (it is
underway). For now, the paradigm continues as it existed
prior. io channel allocates N msix and N WQs (N=4 default)
and either round robins or uses cpu # modulo N for scheduling.
A bunch of module parameters allow the configuration to be
tuned.
NVME (initiator):
Allocates an msix per cpu (or whatever pci_alloc_irq_vectors
gets)
Allocates a WQ per cpu, and maps the WQs to msix on a WQ #
modulo msix vector count basis.
Module parameters exist to cap/control the config if desired.
- Each protocol has its own buffer and dma pools.

I apologize for the size of the patch.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>

----
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

lpfc: nvmet: Add support for NVME LS request hosthandle

As the nvmet layer does not have the concept of a remoteport object, which
can be used to identify the entity on the other end of

lpfc: nvmet: Add support for NVME LS request hosthandle

As the nvmet layer does not have the concept of a remoteport object, which
can be used to identify the entity on the other end of the fabric that is
to receive an LS, the hosthandle was introduced. The driver passes the
hosthandle, a value representative of the remote port, with a ls request
receive. The LS request will create the association. The transport will
remember the hosthandle for the association, and if there is a need to
initiate a LS request to the remote port for the association, the
hosthandle will be used. When the driver loses connectivity with the
remote port, it needs to notify the transport that the hosthandle is no
longer valid, allowing the transport to terminate associations related to
the hosthandle.

This patch adds support to the driver for the hosthandle. The driver will
use the ndlp pointer of the remote port for the hosthandle in calls to
nvmet_fc_rcv_ls_req(). The discovery engine is updated to invalidate the
hosthandle whenever connectivity with the remote port is lost.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

lpfc: Refactor Send LS Response support

Currently, the ability to send an NVME LS response is limited to the nvmet
(controller/target) side of the driver. In preparation of both the nvm

lpfc: Refactor Send LS Response support

Currently, the ability to send an NVME LS response is limited to the nvmet
(controller/target) side of the driver. In preparation of both the nvme
and nvmet sides supporting Send LS Response, rework the existing send
ls_rsp and ls_rsp completion routines such that there is common code that
can be used by both sides.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

lpfc: Refactor Send LS Abort support

Send LS Abort support is needed when Send LS Request is supported.

Currently, the ability to abort an NVME LS request is limited to the nvme

lpfc: Refactor Send LS Abort support

Send LS Abort support is needed when Send LS Request is supported.

Currently, the ability to abort an NVME LS request is limited to the nvme
(host) side of the driver. In preparation of both the nvme and nvmet sides
supporting Send LS Abort, rework the existing ls_req abort routines such
that there is common code that can be used by both sides.

While refactoring it was seen the logic in the abort routine was incorrect.
It attempted to abort all NVME LS's on the indicated port. As such, the
routine was reworked to abort only the NVME LS request that was specified.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

lpfc: Refactor Send LS Request support

Currently, the ability to send an NVME LS request is limited to the nvme
(host) side of the driver. In preparation of both the nvme and nvmet side

lpfc: Refactor Send LS Request support

Currently, the ability to send an NVME LS request is limited to the nvme
(host) side of the driver. In preparation of both the nvme and nvmet sides
support Send LS Request, rework the existing send ls_req and ls_req
completion routines such that there is common code that can be used by
both sides.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

lpfc: Refactor NVME LS receive handling

In preparation for supporting both intiator mode and target mode
receiving NVME LS's, commonize the existing NVME LS request receive
handling

lpfc: Refactor NVME LS receive handling

In preparation for supporting both intiator mode and target mode
receiving NVME LS's, commonize the existing NVME LS request receive
handling found in the base driver and in the nvmet side.

Using the original lpfc_nvmet_unsol_ls_event() and
lpfc_nvme_unsol_ls_buffer() routines as a templates, commonize the
reception of an NVME LS request. The common routine will validate the LS
request, that it was received from a logged-in node, and allocate a
lpfc_async_xchg_ctx that is used to manage the LS request. The role of
the port is then inspected to determine which handler is to receive the
LS - nvme or nvmet. As such, the nvmet handler is tied back in. A handler
is created in nvme and is stubbed out.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

lpfc: Commonize lpfc_async_xchg_ctx state and flag definitions

The last step of commonization is to remove the 'T' suffix from
state and flag field definitions. This is minor, but remov

lpfc: Commonize lpfc_async_xchg_ctx state and flag definitions

The last step of commonization is to remove the 'T' suffix from
state and flag field definitions. This is minor, but removes the
mental association that it solely applies to nvmet use.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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lpfc: Refactor nvmet_rcv_ctx to create lpfc_async_xchg_ctx

To support FC-NVME-2 support (actually FC-NVME (rev 1) with Ammendment 1),
both the nvme (host) and nvmet (controller/target) s

lpfc: Refactor nvmet_rcv_ctx to create lpfc_async_xchg_ctx

To support FC-NVME-2 support (actually FC-NVME (rev 1) with Ammendment 1),
both the nvme (host) and nvmet (controller/target) sides will need to be
able to receive LS requests. Currently, this support is in the nvmet side
only. To prepare for both sides supporting LS receive, rename
lpfc_nvmet_rcv_ctx to lpfc_async_xchg_ctx and commonize the definition.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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lpfc: Refactor lpfc nvme headers

A lot of files in lpfc include nvme headers, building up relationships that
require a file to change for its headers when there is no other change
ne

lpfc: Refactor lpfc nvme headers

A lot of files in lpfc include nvme headers, building up relationships that
require a file to change for its headers when there is no other change
necessary. It would be better to localize the nvme headers.

There is also no need for separate nvme (initiator) and nvmet (tgt)
header files.

Refactor the inclusion of nvme headers so that all nvme items are
included by lpfc_nvme.h

Merge lpfc_nvmet.h into lpfc_nvme.h so that there is a single header used
by both the nvme and nvmet sides. This prepares for structure sharing
between the two roles. Prep to add shared function prototypes for upcoming
shared routines.

Signed-off-by: Paul Ely <paul.ely@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
"This is mostly update of the usual drivers: arcmsr, qla2xxx, lp

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
"This is mostly update of the usual drivers: arcmsr, qla2xxx, lpfc,
hisi_sas, target/iscsi and target/core.

Additionally Christoph refactored gdth as part of the dma changes. The
major mid-layer change this time is the removal of bidi commands and
with them the whole of the osd/exofs driver and filesystem. This is a
major simplification for block and mq in particular"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (240 commits)
scsi: cxgb4i: validate tcp sequence number only if chip version <= T5
scsi: cxgb4i: get pf number from lldi->pf
scsi: core: replace GFP_ATOMIC with GFP_KERNEL in scsi_scan.c
scsi: mpt3sas: Add missing breaks in switch statements
scsi: aacraid: Fix missing break in switch statement
scsi: kill command serial number
scsi: csiostor: drop serial_number usage
scsi: mvumi: use request tag instead of serial_number
scsi: dpt_i2o: remove serial number usage
scsi: st: osst: Remove negative constant left-shifts
scsi: ufs-bsg: Allow reading descriptors
scsi: ufs: Allow reading descriptor via raw upiu
scsi: ufs-bsg: Change the calling convention for write descriptor
scsi: ufs: Remove unused device quirks
Revert "scsi: ufs: disable vccq if it's not needed by UFS device"
scsi: megaraid_sas: Remove a bunch of set but not used variables
scsi: clean obsolete return values of eh_timed_out
scsi: sd: Optimal I/O size should be a multiple of physical block size
scsi: MAINTAINERS: SCSI initiator and target tweaks
scsi: fcoe: make use of fip_mode enum complete
...

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scsi: lpfc: Update 12.2.0.0 file copyrights to 2019

For files modified as part of 12.2.0.0 patches, update copyright to 2019

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>

scsi: lpfc: Update 12.2.0.0 file copyrights to 2019

For files modified as part of 12.2.0.0 patches, update copyright to 2019

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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scsi: lpfc: Adapt partitioned XRI lists to efficient sharing

The XRI get/put lists were partitioned per hardware queue. However, the
adapter rarely had sufficient resources to give a lar

scsi: lpfc: Adapt partitioned XRI lists to efficient sharing

The XRI get/put lists were partitioned per hardware queue. However, the
adapter rarely had sufficient resources to give a large number of resources
per queue. As such, it became common for a cpu to encounter a lack of XRI
resource and request the upper io stack to retry after returning a BUSY
condition. This occurred even though other cpus were idle and not using
their resources.

Create as efficient a scheme as possible to move resources to the cpus that
need them. Each cpu maintains a small private pool which it allocates from
for io. There is a watermark that the cpu attempts to keep in the private
pool. The private pool, when empty, pulls from a global pool from the
cpu. When the cpu's global pool is empty it will pull from other cpu's
global pool. As there many cpu global pools (1 per cpu or hardware queue
count) and as each cpu selects what cpu to pull from at different rates and
at different times, it creates a radomizing effect that minimizes the
number of cpu's that will contend with each other when the steal XRI's from
another cpu's global pool.

On io completion, a cpu will push the XRI back on to its private pool. A
watermark level is maintained for the private pool such that when it is
exceeded it will move XRI's to the CPU global pool so that other cpu's may
allocate them.

On NVME, as heartbeat commands are critical to get placed on the wire, a
single expedite pool is maintained. When a heartbeat is to be sent, it will
allocate an XRI from the expedite pool rather than the normal cpu
private/global pools. On any io completion, if a reduction in the expedite
pools is seen, it will be replenished before the XRI is placed on the cpu
private pool.

Statistics are added to aid understanding the XRI levels on each cpu and
their behaviors.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...