- 02 Jun, 2020 15 commits
-
-
Chuck Lever authored
The restrack ID for an rdma_cm_id is not assigned until it is associated with a device. Here's an example I captured while testing NFS/RDMA's support for DEVICE_REMOVAL. The new tracepoint name is "cm_id_attach". <...>-4261 [001] 366.581299: cm_event_handler: cm.id=0 src=0.0.0.0:45919 dst=192.168.2.55:20049 tos=0 ADDR_ERROR (1/-19) <...>-4261 [001] 366.581304: cm_event_done: cm.id=0 src=0.0.0.0:45919 dst=192.168.2.55:20049 tos=0 ADDR_ERROR consumer returns 0 <...>-1950 [000] 366.581309: cm_id_destroy: cm.id=0 src=0.0.0.0:45919 dst=192.168.2.55:20049 tos=0 <...>-7 [001] 369.589400: cm_event_handler: cm.id=0 src=0.0.0.0:49023 dst=192.168.2.55:20049 tos=0 ADDR_ERROR (1/-19) <...>-7 [001] 369.589404: cm_event_done: cm.id=0 src=0.0.0.0:49023 dst=192.168.2.55:20049 tos=0 ADDR_ERROR consumer returns 0 <...>-1950 [000] 369.589407: cm_id_destroy: cm.id=0 src=0.0.0.0:49023 dst=192.168.2.55:20049 tos=0 <...>-4261 [001] 372.597650: cm_id_attach: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 device=mlx4_0 <...>-4261 [001] 372.597652: cm_event_handler: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 ADDR_RESOLVED (0/0) <...>-4261 [001] 372.597654: cm_event_done: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 ADDR_RESOLVED consumer returns 0 <...>-4261 [001] 372.597738: cm_event_handler: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 ROUTE_RESOLVED (2/0) <...>-4261 [001] 372.597740: cm_event_done: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 ROUTE_RESOLVED consumer returns 0 <...>-4691 [007] 372.600101: cm_qp_create: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 pd.id=2 qp_type=RC send_wr=4091 recv_wr=256 qp_num=530 rc=0 <...>-4691 [007] 372.600207: cm_send_req: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 qp_num=530 <...>-185 [002] 372.601212: cm_send_mra: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 <...>-185 [002] 372.601362: cm_send_rtu: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 <...>-185 [002] 372.601372: cm_event_handler: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 ESTABLISHED (9/0) <...>-185 [002] 372.601379: cm_event_done: cm.id=0 src=192.168.2.51:47492 dst=192.168.2.55:20049 tos=0 ESTABLISHED consumer returns 0 Fixes: ed999f82 ("RDMA/cma: Add trace points in RDMA Connection Manager") Link: https://lore.kernel.org/r/20200530174934.21362.56754.stgit@manet.1015granger.netSigned-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Dan Carpenter authored
The hfi1_vnic_up() function doesn't check whether hfi1_netdev_rx_init() returns errors. In hfi1_vnic_init() we need to change the code to preserve the error code instead of returning success. Fixes: 2280740f ("IB/hfi1: Virtual Network Interface Controller (VNIC) HW support") Fixes: 4730f4a6 ("IB/hfi1: Activate the dummy netdev") Link: https://lore.kernel.org/r/20200530140224.GA1330098@mwandaSigned-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Jason Gunthorpe authored
Now that FMR support is gone, this attribute can be deleted from all places. Link: https://lore.kernel.org/r/13-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comReviewed-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Jason Gunthorpe authored
Now that FMR support is gone, this attribute can be deleted from all places. Link: https://lore.kernel.org/r/12-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comReviewed-by: Max Gurtovoy <maxg@mellanox.com> Reviewed-by: Bernard Metzler <bmt@zurich.ibm.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Max Gurtovoy authored
After removing FMR support from all the RDMA ULPs and providers, there is no need to keep FMR operation for IB devices. Link: https://lore.kernel.org/r/11-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comSigned-off-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Max Gurtovoy authored
Use FRWR method to register memory by default and remove the ancient and unsafe FMR method. Link: https://lore.kernel.org/r/10-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comSigned-off-by: Max Gurtovoy <maxg@mellanox.com> Tested-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Max Gurtovoy authored
Remove the ancient and unsafe FMR method. Link: https://lore.kernel.org/r/9-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comReviewed-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Max Gurtovoy authored
HCA's that are driven by mlx4 driver support FRWR method to register memory. Remove the ancient and unsafe FMR method. Link: https://lore.kernel.org/r/8-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comReviewed-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Jason Gunthorpe authored
The ibfmr member is never referenced, remove it. Link: https://lore.kernel.org/r/7-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comReviewed-by: Max Gurtovoy <maxg@mellanox.com> Acked-by: Shiraz Saleem <shiraz.saleem@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Jason Gunthorpe authored
The bnxt_re_fmr struct is never referenced and the max_fmr items in bnxt_qplib_dev_attr are never read. Link: https://lore.kernel.org/r/6-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comReviewed-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Gal Pressman authored
Remove a few leftovers from FMR functionality which are no longer used. Link: https://lore.kernel.org/r/5-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comSigned-off-by: Gal Pressman <galpress@amazon.com> Signed-off-by: Max Gurtovoy <maxg@mellanox.com> Acked-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Max Gurtovoy authored
This ancient and unsafe method for memory registration is no longer used by any RDMA based ULP. Remove the FMR pool API from the core driver. Link: https://lore.kernel.org/r/4-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comSigned-off-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Max Gurtovoy authored
Use FRWR method for memory registration by default and remove the ancient and unsafe FMR method. Link: https://lore.kernel.org/r/3-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comSigned-off-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Max Gurtovoy authored
FMR is not supported on most recent RDMA devices (that use fast memory registration mechanism). Also, FMR was recently removed from NFS/RDMA ULP. Link: https://lore.kernel.org/r/2-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comSigned-off-by: Max Gurtovoy <maxg@mellanox.com> Reviewed-by: Israel Rukshin <israelr@mellanox.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Israel Rukshin authored
FMR is not supported on most recent RDMA devices (that use fast memory registration mechanism). Also, FMR was recently removed from NFS/RDMA ULP. Link: https://lore.kernel.org/r/1-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.comSigned-off-by: Israel Rukshin <israelr@mellanox.com> Signed-off-by: Max Gurtovoy <maxg@mellanox.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
- 29 May, 2020 11 commits
-
-
Yamin Friedman authored
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.comSigned-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>
-
Yamin Friedman authored
A pre-step for adding shared CQs. Add the infrastructure to prevent shared CQ users from altering the CQ configurations. For now all cqs are marked as private (non-shared). The core driver should use the new force functions to perform resize/destroy/moderation changes that are not allowed for users of shared CQs. Link: https://lore.kernel.org/r/1590568495-101621-2-git-send-email-yaminf@mellanox.comSigned-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>
-
Qiushi Wu authored
kobject_init_and_add() takes reference even when it fails. If this function returns an error, kobject_put() must be called to properly clean up the memory associated with the object. Previous commit b8eb7183 ("net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject") fixed a similar problem. Link: https://lore.kernel.org/r/20200528030231.9082-1-wu000273@umn.eduSigned-off-by: Qiushi Wu <wu000273@umn.edu> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Colin Ian King authored
There is a spelling mistake in an error message. Fix it. Link: https://lore.kernel.org/r/20200528110709.400935-1-colin.king@canonical.comSigned-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Jason Gunthorpe authored
No reason to open code this. Link: https://lore.kernel.org/r/0-v1-0bc346e08476+585-drop_offsetofend_jgg@mellanox.comSigned-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Colin Ian King authored
The pointer raq is being assigned twice. Fix this by removing one of the redundant assignments. Fixes: 14ba8730 ("RDMA/hns: Remove redundant type cast for general pointers") Link: https://lore.kernel.org/r/20200528150427.420624-1-colin.king@canonical.com Addressses-Coverity: ("Evaluation order violation") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Mark Zhang authored
The mlx5 VF driver doesn't set QP tx port affinity because it doesn't know if the lag is active or not, since the "lag_active" works only for PF interfaces. In this case for VF interfaces only one lag is used which brings performance issue. Add a lag_tx_port_affinity CAP bit; When it is enabled and "num_lag_ports > 1", then driver always set QP tx affinity, regardless of lag state. Link: https://lore.kernel.org/r/20200527055014.355093-1-leon@kernel.orgSigned-off-by: Mark Zhang <markz@mellanox.com> Reviewed-by: Maor Gottlieb <maorg@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Bart Van Assche authored
The ib_srpt driver limits max_send_sge to 16. Since that is a workaround for an mlx4 bug that has been fixed, increase max_send_sge. See also commit f95ccffc ("IB/mlx4: Use 4K pages for kernel QP's WQE buffer"). Link: https://lore.kernel.org/r/20200525172212.14413-5-bvanassche@acm.orgSigned-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Bart Van Assche authored
Since srpt_post_recv() always sets num_sge to 1, reduce the max_recv_sge parameter that is used at queue pair allocation time to 1. Link: https://lore.kernel.org/r/20200525172212.14413-4-bvanassche@acm.orgSigned-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Bart Van Assche authored
Since the session name by itself is not sufficient to uniquely identify a queue pair, include the queue pair number. Show the ASCII channel state name instead of the numeric value. This change makes the ib_srpt debug output more consistent. Link: https://lore.kernel.org/r/20200525172212.14413-3-bvanassche@acm.orgSigned-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Bart Van Assche authored
Increase the flexibility of the SRP initiator driver by making the channel count configurable per target instead of only providing a kernel module parameter for configuring the channel count. Link: https://lore.kernel.org/r/20200525172212.14413-2-bvanassche@acm.orgSigned-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
- 27 May, 2020 14 commits
-
-
Leon Romanovsky authored
After users sets the ECE option, FW will return the agreed/supported bits through an output structures of modify QP stages for regular QPs or through create QP for the DCT. Link: https://lore.kernel.org/r/20200526115440.205922-9-leon@kernel.orgReviewed-by: Mark Zhang <markz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
The most common way to set ECE option will be during modify QP command in INIT2RTR, RTR2RTS and RTS2RTS stages, so update mlx5 to support it. The new bit in the comp_mask is needed to mark that kernel supports ECE and can receive data instead of "reserved" field in the struct mlx5_ib_modify_qp. Link: https://lore.kernel.org/r/20200526115440.205922-8-leon@kernel.orgReviewed-by: Mark Zhang <markz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
Instead of hand crafted mlx5_qp_context and mlx5_qp_path use common MLX5_SET() macros. Link: https://lore.kernel.org/r/20200526115440.205922-7-leon@kernel.orgReviewed-by: Maor Gottlieb <maorg@mellanox.com> Reviewed-by: Mark Zhang <markz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
As a preparation to removal hand crafted mlx5_qp_context, convert query_qp_attr() to use proper MLX5_GET() macros. Link: https://lore.kernel.org/r/20200526115440.205922-6-leon@kernel.orgReviewed-by: Mark Zhang <markz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
As a preparation to removal hand crafted mlx5_qp_context, convert counter code to use mlx5_cmd_exec_in() directly. Link: https://lore.kernel.org/r/20200526115440.205922-5-leon@kernel.orgReviewed-by: Mark Zhang <markz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
Allow users to ask creation of QPs with specific ECE options. Such early set even before RDMA-CM connection is established is useful if user knows exactly which option he needs. Link: https://lore.kernel.org/r/20200526115440.205922-4-leon@kernel.orgReviewed-by: Mark Zhang <markz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
Supported ECE options are returned from FW in the create_qp phase and zero means that field is not valid. Such default value allows us to reuse reserved field without worries about comp_mask. Update create QP API to return ECE options. Link: https://lore.kernel.org/r/20200526115440.205922-3-leon@kernel.orgReviewed-by: Mark Zhang <markz@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
IBTA declares "vendor option not supported" reject reason in REJ messages if passive side doesn't want to accept proposed ECE options. Due to the fact that ECE is managed by userspace, there is a need to let users to provide such rejected reason. Link: https://lore.kernel.org/r/20200526103304.196371-7-leon@kernel.orgSigned-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
The rdma_accept() is called by both passive and active sides of CMID connection to mark readiness to start data transfer. For passive side, this is called explicitly, for active side, it is called implicitly while receiving REP message. Provide ECE data to rdma_accept function needed for passive side to send that REP message. Link: https://lore.kernel.org/r/20200526103304.196371-6-leon@kernel.orgSigned-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
ECE parameters are exchanged through REQ->REP/SIDR_REP messages, this patch adds the data to provide to other side of CMID communication channel. Link: https://lore.kernel.org/r/20200526103304.196371-5-leon@kernel.orgSigned-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
Passive side of CMID connection receives ECE request through REQ message and needs to respond with relevant REP message which will be forwarded to active side. The UCMA events interface is responsible for such communication with the user space (librdmacm). Extend it to provide ECE wire data. Link: https://lore.kernel.org/r/20200526103304.196371-4-leon@kernel.orgSigned-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
Active side of CMID initiates connection through librdmacm's rdma_connect() and kernel's ucma_connect(). Extend UCMA interface to handle those new parameters. Link: https://lore.kernel.org/r/20200526103304.196371-3-leon@kernel.orgSigned-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Leon Romanovsky authored
Extend REQ (request for communications), REP (reply to request for communication), rejected reason and SIDR_REP (service ID resolution response) structures with hardware vendor ID bits according to IBTA v1.4. Link: https://lore.kernel.org/r/20200526103304.196371-2-leon@kernel.orgSigned-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-
Jason Gunthorpe authored
From the mlx5-next branch at git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux Required for dependencies in following patches * branch 'mellanox/mlx5-next': net/mlx5: Add ability to read and write ECE options net/mlx5: Add support for RDMA TX FT headers modifying net/mlx5: Move iseg access helper routines close to mlx5_core driver net/mlx5: Cleanup mlx5_ifc_fte_match_set_misc2_bits Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-