IB/hfi1: Silence txreq allocation warnings

IB/hfi1: Silence txreq allocation warnings

The following warning can happen when a memory shortage
occurs during txreq allocation:

[10220.939246] SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
[10220.939246] Hardware name: Intel Corporation S2600WT2R/S2600WT2R, BIOS SE5C610.86B.01.01.0018.C4.072020161249 07/20/2016
[10220.939247]   cache: mnt_cache, object size: 384, buffer size: 384, default order: 2, min order: 0
[10220.939260] Workqueue: hfi0_0 _hfi1_do_send [hfi1]
[10220.939261]   node 0: slabs: 1026568, objs: 43115856, free: 0
[10220.939262] Call Trace:
[10220.939262]   node 1: slabs: 820872, objs: 34476624, free: 0
[10220.939263]  dump_stack+0x5a/0x73
[10220.939265]  warn_alloc+0x103/0x190
[10220.939267]  ? wake_all_kswapds+0x54/0x8b
[10220.939268]  __alloc_pages_slowpath+0x86c/0xa2e
[10220.939270]  ? __alloc_pages_nodemask+0x2fe/0x320
[10220.939271]  __alloc_pages_nodemask+0x2fe/0x320
[10220.939273]  new_slab+0x475/0x550
[10220.939275]  ___slab_alloc+0x36c/0x520
[10220.939287]  ? hfi1_make_rc_req+0x90/0x18b0 [hfi1]
[10220.939299]  ? __get_txreq+0x54/0x160 [hfi1]
[10220.939310]  ? hfi1_make_rc_req+0x90/0x18b0 [hfi1]
[10220.939312]  __slab_alloc+0x40/0x61
[10220.939323]  ? hfi1_make_rc_req+0x90/0x18b0 [hfi1]
[10220.939325]  kmem_cache_alloc+0x181/0x1b0
[10220.939336]  hfi1_make_rc_req+0x90/0x18b0 [hfi1]
[10220.939348]  ? hfi1_verbs_send_dma+0x386/0xa10 [hfi1]
[10220.939359]  ? find_prev_entry+0xb0/0xb0 [hfi1]
[10220.939371]  hfi1_do_send+0x1d9/0x3f0 [hfi1]
[10220.939372]  process_one_work+0x171/0x380
[10220.939374]  worker_thread+0x49/0x3f0
[10220.939375]  kthread+0xf8/0x130
[10220.939377]  ? max_active_store+0x80/0x80
[10220.939378]  ? kthread_bind+0x10/0x10
[10220.939379]  ret_from_fork+0x35/0x40
[10220.939381] SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)

The shortage is handled properly so the message isn't needed. Silence by
adding the no warn option to the slab allocation.

Fixes: 45842abbb292 ("staging/rdma/hfi1: move txreq header code")
Cc: <stable@vger.kernel.org>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>