RDMA/core: Delete useless module.h include

There is no need in include of module.h in the following files.

Link: https://lore.kernel.org/r/e412c83b45b6ebdd937886cc9c2cc7c8abcc34fa.1642960861.git.leonro@nvidia.com
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Clean up cq pool mechanism

The CQ pool mechanism had two problems:

1. The CQ pool lists were uninitialized in the device registration error
flow. As a result, all the list pointers remained NULL. This caused
the kernel to crash (in procedure ib_cq_pool_destroy) when that error
flow was taken (and unregister called). The stack trace snippet:

BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0×0000) ? not-present page
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
. . .
RIP: 0010:ib_cq_pool_destroy+0x1b/0×70 [ib_core]
. . .
Call Trace:
disable_device+0x9f/0×130 [ib_core]
__ib_unregister_device+0x35/0×90 [ib_core]
ib_register_device+0x529/0×610 [ib_core]
__mlx5_ib_add+0x3a/0×70 [mlx5_ib]
mlx5_add_device+0x87/0×1c0 [mlx5_core]
mlx5_register_interface+0x74/0xc0 [mlx5_core]
do_one_initcall+0x4b/0×1f4
do_init_module+0x5a/0×223
load_module+0x1938/0×1d40

2. At device unregister, when cleaning up the cq pool, the cq's in the
pool lists were freed, but the cq entries were left in the list.

The fix for the first issue is to initialize the cq pool lists when the
ib_device structure is allocated for a new device (in procedure
_ib_alloc_device).

The fix for the second problem is to delete cq entries from the pool lists
when cleaning up the cq pool.

In addition, procedure ib_cq_pool_destroy() is renamed to the more
appropriate name ib_cq_pool_cleanup().

Fixes: 4aa1615268a8 ("RDMA/core: Fix ordering of CQ pool destruction")
Link: https://lore.kernel.org/r/20201208073545.9723-2-leon@kernel.org
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB: Fix kernel-doc markups

Some functions have different names between their prototypes and the
kernel-doc markup.

Others need to be fixed, as kernel-doc markups should use this format:
identifier - description

Link: https://lore.kernel.org/r/78b98c41a5a0f4c0106433d305b143028a4168b0.1606823973.git.mchehab+huawei@kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/restrack: Improve readability in task name management

Use rdma_restrack_set_name() and rdma_restrack_parent_name() instead of
tricky uses of rdma_restrack_attach_task()/rdma_restrack_uadd().

This uniformly makes all restracks add'd using rdma_restrack_add().

Link: https://lore.kernel.org/r/20200922091106.2152715-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/restrack: Simplify restrack tracking in kernel flows

Have a single rdma_restrack_add() that adds an entry, there is no reason
to split the user/kernel here, the rdma_restrack_set_task() is responsible
for this difference.

This patch prepares the code to the future requirement of making restrack
is mandatory for managing ib objects.

Link: https://lore.kernel.org/r/20200922091106.2152715-5-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/restrack: Count references to the verbs objects

Refactor the restrack code to make sure the kref inside the restrack entry
properly kref's the object in which it is embedded. This slight change is
needed for future conversions of MR and QP which are refcounted before the
release and kfree.

The ideal flow from ib_core perspective as follows:
* Allocate ib_* structure with rdma_zalloc_*.
* Set everything that is known to ib_core to that newly created object.
* Initialize kref with restrack help
* Call to driver specific allocation functions.
* Insert into restrack DB
....
* Return and release restrack with restrack_put.

Largely this means a rdma_restrack_new() should be called near allocating
the containing structure.

Link: https://lore.kernel.org/r/20200922091106.2152715-4-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA: Allow fail of destroy CQ

Like any other verbs objects, CQ shouldn't fail during destroy, but
mlx5_ib didn't follow this contract with mixed IB verbs objects with
DEVX. Such mix causes to the situation where FW and kernel are fully
interdependent on the reference counting of each side.

Kernel verbs and drivers that don't have DEVX flows shouldn't fail.

Fixes: e39afe3d6dbd ("RDMA: Convert CQ allocations to be under core responsibility")
Link: https://lore.kernel.org/r/20200907120921.476363-7-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Delete function indirection for alloc/free kernel CQ

The ib_alloc_cq*() and ib_free_cq*() are solely kernel verbs to manage CQs
and doesn't need extra indirection just to call same functions with
constant parameter NULL as udata.

Link: https://lore.kernel.org/r/20200907120921.476363-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Fix unsafe linked list traversal after failing to allocate CQ

It's not safe to access the next CQ in list_for_each_entry() after
invoking ib_free_cq(), because the CQ has already been freed in current
iteration. It should be replaced by list_for_each_entry_safe().

Fixes: c7ff819aefea ("RDMA/core: Introduce shared CQ pool API")
Link: https://lore.kernel.org/r/1598963935-32335-1-git-send-email-liweihang@huawei.com
Signed-off-by: Xi Wang <wangxi11@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Free DIM memory in error unwind

The memory allocated for the DIM wasn't freed in in error unwind path, fix
it by calling to rdma_dim_destroy().

Fixes: da6629793aa6 ("RDMA/core: Provide RDMA DIM support for ULPs")
Link: https://lore.kernel.org/r/20200730082719.1582397-4-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com <mailto:maxg@mellanox.com>>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Stop DIM before destroying CQ

HW destroy operation should be last operation after all possible CQ users
completed their work, so move DIM work cancellation before such destroy
call.

Fixes: da6629793aa6 ("RDMA/core: Provide RDMA DIM support for ULPs")
Link: https://lore.kernel.org/r/20200730082719.1582397-3-leon@kernel.org
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Introduce shared CQ pool API

Allow a ULP to ask the core to provide a completion queue based on a
least-used search on a per-device CQ pools. The device CQ pools grow in a
lazy fashion when more CQs are requested.

This feature reduces the amount of interrupts when using many QPs. Using
shared CQs allows for more effcient completion handling. It also reduces
the amount of overhead needed for CQ contexts.

Test setup:
Intel(R) Xeon(R) Platinum 8176M CPU @ 2.10GHz servers.
Running NVMeoF 4KB read IOs over ConnectX-5EX across Spectrum switch.
TX-depth = 32. The patch was applied in the nvme driver on both the target
and initiator. Four controllers are accessed from each core. In the
current test case we have exposed sixteen NVMe namespaces using four
different subsystems (four namespaces per subsystem) from one NVM port.
Each controller allocated X queues (RDMA QPs) and attached to Y CQs.
Before this series we had X == Y, i.e for four controllers we've created
total of 4X QPs and 4X CQs. In the shared case, we've created 4X QPs and
only X CQs which means that we have four controllers that share a
completion queue per core. Until fourteen cores there is no significant
change in performance and the number of interrupts per second is less than
a million in the current case.
==================================================
|Cores|Current KIOPs |Shared KIOPs |improvement|
|-----|---------------|--------------|-----------|
|14 |2332 |2723 |16.7% |
|-----|---------------|--------------|-----------|
|20 |2086 |2712 |30% |
|-----|---------------|--------------|-----------|
|28 |1971 |2669 |35.4% |
|=================================================
|Cores|Current avg lat|Shared avg lat|improvement|
|-----|---------------|--------------|-----------|
|14 |767us |657us |14.3% |
|-----|---------------|--------------|-----------|
|20 |1225us |943us |23% |
|-----|---------------|--------------|-----------|
|28 |1816us |1341us |26.1% |
========================================================
|Cores|Current interrupts|Shared interrupts|improvement|
|-----|------------------|-----------------|-----------|
|14 |1.6M/sec |0.4M/sec |72% |
|-----|------------------|-----------------|-----------|
|20 |2.8M/sec |0.6M/sec |72.4% |
|-----|------------------|-----------------|-----------|
|28 |2.9M/sec |0.8M/sec |63.4% |
====================================================================
|Cores|Current 99.99th PCTL lat|Shared 99.99th PCTL lat|improvement|
|-----|------------------------|-----------------------|-----------|
|14 |67ms |6ms |90.9% |
|-----|------------------------|-----------------------|-----------|
|20 |5ms |6ms |-10% |
|-----|------------------------|-----------------------|-----------|
|28 |8.7ms |6ms |25.9% |
|===================================================================

Performance improvement with sixteen disks (sixteen CQs per core) is
comparable.

Link: https://lore.kernel.org/r/1590568495-101621-3-git-send-email-yaminf@mellanox.com
Signed-off-by: Yamin Friedman <yaminf@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Trace points for diagnosing completion queue issues

Sample trace events:

kworker/u29:0-300 [007] 120.042217: cq_alloc: cq.id=4 nr_cqe=161 comp_vector=2 poll_ctx=WORKQUEUE
<idle>-0 [002] 120.056292: cq_schedule: cq.id=4
kworker/2:1H-482 [002] 120.056402: cq_process: cq.id=4 wake-up took 109 [us] from interrupt
kworker/2:1H-482 [002] 120.056407: cq_poll: cq.id=4 requested 16, returned 1
<idle>-0 [002] 120.067503: cq_schedule: cq.id=4
kworker/2:1H-482 [002] 120.067537: cq_process: cq.id=4 wake-up took 34 [us] from interrupt
kworker/2:1H-482 [002] 120.067541: cq_poll: cq.id=4 requested 16, returned 1
<idle>-0 [002] 120.067657: cq_schedule: cq.id=4
kworker/2:1H-482 [002] 120.067672: cq_process: cq.id=4 wake-up took 15 [us] from interrupt
kworker/2:1H-482 [002] 120.067674: cq_poll: cq.id=4 requested 16, returned 1

...

systemd-1 [002] 122.392653: cq_schedule: cq.id=4
kworker/2:1H-482 [002] 122.392688: cq_process: cq.id=4 wake-up took 35 [us] from interrupt
kworker/2:1H-482 [002] 122.392693: cq_poll: cq.id=4 requested 16, returned 16
kworker/2:1H-482 [002] 122.392836: cq_poll: cq.id=4 requested 16, returned 16
kworker/2:1H-482 [002] 122.392970: cq_poll: cq.id=4 requested 16, returned 16
kworker/2:1H-482 [002] 122.393083: cq_poll: cq.id=4 requested 16, returned 16
kworker/2:1H-482 [002] 122.393195: cq_poll: cq.id=4 requested 16, returned 3

Several features to note in this output:
- The WCE count and context type are reported at allocation time
- The CPU and kworker for each CQ is evident
- The CQ's restracker ID is tagged on each trace event
- CQ poll scheduling latency is measured
- Details about how often single completions occur versus multiple
completions are evident
- The cost of the ULP's completion handler is recorded

Link: https://lore.kernel.org/r/20191218201815.30584.3481.stgit@manet.1015granger.net
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

rdma: Enable ib_alloc_cq to spread work over a device's comp_vectors

Send and Receive completion is handled on a single CPU selected at
the time each Completion Queue is allocated. Typically this is when
an initiator instantiates an RDMA transport, or when a target
accepts an RDMA connection.

Some ULPs cannot open a connection per CPU to spread completion
workload across available CPUs and MSI vectors. For such ULPs,
provide an API that allows the RDMA core to select a completion
vector based on the device's complement of available comp_vecs.

ULPs that invoke ib_alloc_cq() with only comp_vector 0 are converted
to use the new API so that their completion workloads interfere less
with each other.

Suggested-by: Håkon Bugge <haakon.bugge@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Cc: <linux-cifs@vger.kernel.org>
Cc: <v9fs-developer@lists.sourceforge.net>
Link: https://lore.kernel.org/r/20190729171923.13428.52555.stgit@manet.1015granger.net
Signed-off-by: Doug Ledford <dledford@redhat.com>

RDMA/core: Fix -Wunused-const-variable warnings

The commit below introduced a few compilation warnings.

In file included from ./include/rdma/ib_verbs.h:64,
from ./include/linux/mlx5/device.h:37,
from ./include/linux/mlx5/driver.h:51,
from drivers/net/ethernet/mellanox/mlx5/core/uar.c:36:
./include/linux/dim.h:378:1: warning: 'rdma_dim_prof' defined but not
used [-Wunused-const-variable=]
rdma_dim_prof[RDMA_DIM_PARAMS_NUM_PROFILES] = {
^~~~~~~~~~~~~
In file included from ./include/rdma/ib_verbs.h:64,
from ./include/linux/mlx5/device.h:37,
from ./include/linux/mlx5/driver.h:51,
from
drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:37:
./include/linux/dim.h:378:1: warning: 'rdma_dim_prof' defined but not
used [-Wunused-const-variable=]
rdma_dim_prof[RDMA_DIM_PARAMS_NUM_PROFILES] = {
^~~~~~~~~~~~~

Since only ib_cq_rdma_dim_work() in drivers/infiniband/core/cq.c uses it,
just move the definition over there.

Fixes: f4915455dcf0 ("linux/dim: Implement RDMA adaptive moderation (DIM)")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Provide RDMA DIM support for ULPs

Added the interface in the infiniband driver that applies the rdma_dim
adaptive moderation. There is now a special function for allocating an
ib_cq that uses rdma_dim.

Performance improvement (ConnectX-5 100GbE, x86) running FIO benchmark over
NVMf between two equal end-hosts with 56 cores across a Mellanox switch
using null_blk device:

READS without DIM:
blk size | BW | IOPS | 99th percentile latency | 99.99th latency
512B | 3.8GiB/s | 7.7M | 1401 usec | 2442 usec
4k | 7.0GiB/s | 1.8M | 4817 usec | 6587 usec
64k | 10.7GiB/s| 175k | 9896 usec | 10028 usec

IO WRITES without DIM:
blk size | BW | IOPS | 99th percentile latency | 99.99th latency
512B | 3.6GiB/s | 7.5M | 1434 usec | 2474 usec
4k | 6.3GiB/s | 1.6M | 938 usec | 1221 usec
64k | 10.7GiB/s| 175k | 8979 usec | 12780 usec

IO READS with DIM:
blk size | BW | IOPS | 99th percentile latency | 99.99th latency
512B | 4GiB/s | 8.2M | 816 usec | 889 usec
4k | 10.1GiB/s| 2.65M| 3359 usec | 5080 usec
64k | 10.7GiB/s| 175k | 9896 usec | 10028 usec

IO WRITES with DIM:
blk size | BW | IOPS | 99th percentile latency | 99.99th latency
512B | 3.9GiB/s | 8.1M | 799 usec | 922 usec
4k | 9.6GiB/s | 2.5M | 717 usec | 1004 usec
64k | 10.7GiB/s| 176k | 8586 usec | 12256 usec

The rdma_dim algorithm was designed to measure the effectiveness of
moderation on the flow in a general way and thus should be appropriate
for all RDMA storage protocols.

rdma_dim is configured to be the default option based on performance
improvement seen after extensive tests.

Signed-off-by: Yamin Friedman <yaminf@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA: Convert CQ allocations to be under core responsibility

Ensure that CQ is allocated and freed by IB/core and not by drivers.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Gal Pressman <galpress@amazon.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Tested-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

RDMA: Clean destroy CQ in drivers do not return errors

Like all other destroy commands, .destroy_cq() call is not supposed
to fail. In all flows, the attempt to return earlier caused to memory
leaks.

This patch converts .destroy_cq() to do not return any errors.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Gal Pressman <galpress@amazon.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation this program
is distributed in the hope it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 263 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

RDMA/core: Fix doc typo

Use the correct function names.

Fixes: c4367a26357b ("IB: Pass uverbs_attr_bundle down ib_x destroy path")
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB: Pass only ib_udata in function prototypes

Now when ib_udata is passed to all the driver's object create/destroy APIs
the ib_udata will carry the ib_ucontext for every user command. There is
no need to also pass the ib_ucontext via the functions prototypes.

Make ib_udata the only argument psssed.

Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB: Pass uverbs_attr_bundle down ib_x destroy path

The uverbs_attr_bundle with the ucontext is sent down to the drivers ib_x
destroy path as ib_udata. The next patch will use the ib_udata to free the
drivers destroy path from the dependency in 'uobject->context' as we
already did for the create path.

Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/restrack: Resource-tracker should not use uobject pointers

Having uobject pointer embedded in ib core objects is not aligned with a
future shared ib_x model. The resource tracker only does this to keep
track of user/kernel objects - track this directly instead.

Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA: Start use ib_device_ops

Make all the required change to start use the ib_device_ops structure.

Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/restrack: Consolidate task name updates in one place

Unify task update and kernel name set in one place.

Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Reviewed-by: Yossi Itigin <yosefe@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/core: Add an unbound WQ type to the new CQ API

The upstream kernel commit cited below modified the workqueue in the
new CQ API to be bound to a specific CPU (instead of being unbound).
This caused ALL users of the new CQ API to use the same bound WQ.

Specifically, MAD handling was severely delayed when the CPU bound
to the WQ was busy handling (higher priority) interrupts.

This caused a delay in the MAD "heartbeat" response handling,
which resulted in ports being incorrectly classified as "down".

To fix this, add a new "unbound" WQ type to the new CQ API, so that users
have the option to choose either a bound WQ or an unbound WQ.

For MADs, choose the new "unbound" WQ.

Fixes: b7363e67b23e ("IB/device: Convert ib-comp-wq to be CPU-bound")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.m>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Reduce poll batch for direct cq polling

Fix warning limit for kernel stack consumption:

drivers/infiniband/core/cq.c: In function 'ib_process_cq_direct':
drivers/infiniband/core/cq.c:78:1: error: the frame size of 1032 bytes
is larger than 1024 bytes [-Werror=frame-larger-than=]

Using smaller ib_wc array on the stack brings us comfortably below that
limit again.

Fixes: 246d8b184c10 ("IB/cq: Don't force IB_POLL_DIRECT poll context for ib_process_cq_direct")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Sergey Gorenko <sergeygo@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Add resource tracking for create and destroy CQs

Track create and destroy operations of CQ objects.

Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Save kernel caller name when creating PD and CQ objects

The KBUILD_MODNAME variable contains the module name and it is known for
kernel users during compilation, so let's reuse it to track the owners.

Followup patches will store this for resource tracking.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/cq: Don't force IB_POLL_DIRECT poll context for ib_process_cq_direct

polling the completion queue directly does not interfere
with the existing polling logic, hence drop the requirement.
Be aware that running ib_process_cq_direct with non IB_POLL_DIRECT
CQ may trigger concurrent CQ processing.

This can be used for polling mode ULPs.

Cc: Bart Van Assche <bart.vanassche@wdc.com>
Reported-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
[maxg: added wcs array argument to __ib_process_cq]
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/cq: Don't process more than the given budget

The caller might not want this overhead.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Protect against self-requeue of a cq work item

We need to make sure that the cq work item does not
run when we are destroying the cq. Unlike flush_work,
cancel_work_sync protects against self-requeue of the
work item (which we can do in ib_cq_poll_work).

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>--
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Add support for draining IB_POLL_DIRECT completion queues

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Steve Wise <swise@opengridcomputing.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Fix typo in comment

Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB: add a proper completion queue abstraction

This adds an abstraction that allows ULPs to simply pass a completion
object and completion callback with each submitted WR and let the RDMA
core handle the nitty gritty details of how to handle completion
interrupts and poll the CQ.

In detail there is a new ib_cqe structure which just contains the
completion callback, and which can be used to get at the containing
object using container_of. It is pointed to by the WR and WC as an
alternative to the wr_id field, similar to how many ULPs already use
the field to store a pointer using casts.

A driver using the new completion callbacks allocates it's CQs using
the new ib_create_cq API, which in addition to the number of CQEs and
the completion vectors also takes a mode on how we poll for CQEs.
Three modes are available: direct for drivers that never take CQ
interrupts and just poll for them, softirq to poll from softirq context
using the to be renamed blk-iopoll infrastructure which takes care of
rearming and budgeting, or a workqueue for consumer who want to be
called from user context.

Thanks a lot to Sagi Grimberg who helped reviewing the API, wrote
the current version of the workqueue code because my two previous
attempts sucked too much and converted the iSER initiator to the new
API.

Signed-off-by: Christoph Hellwig <hch@lst.de>