Re: [PATCH net-next v3 00/10] optimize the parallelism of SMC-R connections

Jan Karcher
2022-10-21T11:57:33Z

On 20/10/2022 09:00, D. Wythe wrote:
>
> Hi Jan,
>
> Sorry for the long delay, The main purpose of v3 is to put optimizes
> also works on SMC-D, dues to the environment,
> I can only tests it in SMC-R, so please help us to verify the stability
> and functional in SMC-D,
> Thanks a lot.
>
> If you have any problems, please let us know.
>
> Besides, PATCH bug fixes need to be reordered. After the code review
> passes and the SMC-D test goes stable, I will adjust it
> in next serial.
>
>

Hi D. Wythe,

thank you again for your submission. I ran the first tests and here are
my findings:

For SMC-R we are facing problems during unloading of the smc module:

vvvvvvvvvv

[root@testsys10 ~]# dmesg -C
[root@testsys10 ~]# dmesg
[root@testsys10 ~]# rmmod ism
[root@testsys10 ~]# rmmod smc_diag
[root@testsys10 ~]# dmesg
[ 51.671365] smc: removing smcd device 1522:00:00.0
[root@testsys10 ~]# rmmod smc
[root@testsys10 ~]# dmesg
[ 51.671365] smc: removing smcd device 1522:00:00.0
[ 65.378445] NET: Unregistered PF_SMC protocol family
[ 65.378463] ------------[ cut here ]------------
[ 65.378465] WARNING: CPU: 0 PID: 1155 at kernel/workqueue.c:3066
__flush_work.isra.0+0x28a/0x298
[ 65.378476] Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6
nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct
nft_chain_nat nf_nat mlx5_ib nf_conntrack ib_uverbs nf_defrag_ipv6
nf_defrag_ipv4 ip_set nf_tables nfnetlink mlx5_core smc(-) ib_core
vfio_ccw s390_trng mdev vfio_iommu_type1 vfio sch_fq_codel configfs
ghash_s390 prng chacha_s390 libchacha aes_s390 des_s390 libdes
sha3_512_s390 sha3_256_s390 sha512_s390 sha256_s390 sha1_s390 sha_common
pkey zcrypt rng_core autofs4 [last unloaded: smc_diag]
[ 65.378509] CPU: 0 PID: 1155 Comm: rmmod Not tainted
6.1.0-rc1-00035-g9980a965416f #4
[ 65.378514] Hardware name: IBM 8561 T01 701 (z/VM 7.2.0)
[ 65.378517] Krnl PSW : 0704c00180000000 00000000f9d5f17e
(__flush_work.isra.0+0x28e/0x298)
[ 65.378523] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0
PM:0 RI:0 EA:3
[ 65.380675] Krnl GPRS: 8000000000000001 0000000000000000
000003ff7fd40270 0000000000000000
[ 65.380683] 0000038000c73d70 000e002100000000
0000000000000000 0000000000000001
[ 65.380686] 0000038000c73d70 0000000000000000
000003ff7fd40270 000003ff7fd40270
[ 65.380688] 000000009b8d2100 000003ffe38f98f8
0000038000c73cd0 0000038000c73c30
[ 65.380697] Krnl Code: 00000000f9d5f172: a7780000 lhi
%r7,0
00000000f9d5f176: a7f4ff7b brc
15,00000000f9d5f06c
#00000000f9d5f17a: af000000 mc 0,0
>00000000f9d5f17e: a7780000 lhi
%r7,0
00000000f9d5f182: a7f4ff75 brc
15,00000000f9d5f06c
00000000f9d5f186: 0707 bcr
0,%r7
00000000f9d5f188: c004005daa34 brcl
0,00000000fa9145f0
00000000f9d5f18e: ebaff0680024 stmg
%r10,%r15,104(%r15)
[ 65.380773] Call Trace:
[ 65.380774] [<00000000f9d5f17e>] __flush_work.isra.0+0x28e/0x298
[ 65.380779] [<00000000f9d61228>] __cancel_work_timer+0x130/0x1c0
[ 65.380782] [<00000000fa46b1b4>] rhashtable_free_and_destroy+0x2c/0x170
[ 65.380787] [<000003ff7fd3a08e>] smc_exit+0x3e/0x1b8 [smc]
[ 65.380804] [<00000000f9de946a>] __do_sys_delete_module+0x1a2/0x298
[ 65.380809] [<00000000fa8f85ac>] __do_syscall+0x1d4/0x200
[ 65.380814] [<00000000fa907722>] system_call+0x82/0xb0
[ 65.380817] Last Breaking-Event-Address:
[ 65.380818] [<00000000f9d5ef24>] __flush_work.isra.0+0x34/0x298
[ 65.380820] ---[ end trace 0000000000000000 ]---
[ 65.380828] smc: removing ib device mlx5_0
[ 65.380833] smc: removing ib device mlx5_1

^^^^^^^^^^

For SMC-D it seems like your decisionmaker is causing some troubles
(crash). I did not have the time yet to look into it, i still dump you
the console log - maybe you're seeing the problem faster then me:

vvvvvvvvvv

[ 135.528259] smc-tests: test_cs_security started
[ 136.397056] illegal operation: 0001 ilc:1 [#1] SMP
[ 136.397064] Modules linked in: tcp_diag inet_diag ism mlx5_ib
ib_uverbs mlx5_core smc_diag smc ib_core vmur nft_fib_inet nft_fib_
ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6
nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defra
g_ipv6 nf_defrag_ipv4 ip_set nf_tab
[ 136.397093] CPU: 0 PID: 9 Comm: kworker/0:1 Not tainted
6.1.0-rc1-00035-g1c11cab281ca #4
[ 136.397098] Hardware name: IBM 8561 T01 701 (z/VM 7.2.0)
[ 136.397100] Workqueue: smc_hs_wq smc_listen_work [smc]
[ 136.397123] Krnl PSW : 0704e00180000000 0000000000000002 (0x2)
[ 136.397128] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2
PM:0 RI:0 EA:3
[ 136.397133] Krnl GPRS: 0000000000000001 0000000000000000
00000000a5670600 0000000000000000

[ 136.398410] 0000000000000000 000003ff7feee620
00000000000000c8 0000000000000000
[ 136.398417] 000003ff7feed2b8 00000000a5670600
000003ff7feed168 000003ff7fed1628
[ 136.398420] 0000000080334200 0000000000000001
000003ff7fed3ab0 0000037fffb5fa30
[ 136.398425] Krnl Code:#0000000000000000: 0000 illegal
[ 136.398425] >0000000000000002: 0000 illegal
[ 136.398425] 0000000000000004: 0000 illegal
[ 136.398425] 0000000000000006: 0000 illegal
[ 136.398425] 0000000000000008: 0000 illegal
[ 136.398425] 000000000000000a: 0000 illegal
[ 136.398425] 000000000000000c: 0000 illegal
[ 136.398425] 000000000000000e: 0000 illegal
[ 136.398465] Call Trace:
[ 136.398469] [<0000000000000002>] 0x2
[ 136.398472] ([<00000001790fdbde>] release_sock+0x6e/0xd8)
[ 136.398482] [<000003ff7fed746a>] smc_conn_create+0xc2/0x9d8 [smc]
01: HCPGSP2629I The virtual machine is placed in CP mode due to a SIGP
stop from CPU 01.
01: HCPGSP2629I The virtual machine is placed in CP mode due to a SIGP
stop from CPU 00.

[ 136.408436] [<000003ff7fec8206>]
smc_find_ism_v2_device_serv+0x186/0x288 [smc]
[ 136.408444] [<000003ff7fec8336>] smc_listen_find_device+0x2e/0x370 [smc]
[ 136.408452] [<000003ff7fecaa8a>] smc_listen_work+0x2ca/0x580 [smc]
[ 136.408459] [<00000001788481e8>] process_one_work+0x200/0x458
[ 136.408466] [<000000017884896e>] worker_thread+0x66/0x480
[ 136.408470] [<0000000178851888>] kthread+0x108/0x110
[ 136.408474] [<00000001787d72cc>] __ret_from_fork+0x3c/0x58
[ 136.408478] [<00000001793ef75a>] ret_from_fork+0xa/0x40
[ 136.408484] Last Breaking-Event-Address:
[ 136.408486] [<000003ff7fed3aae>]
smc_get_or_create_lgr_decision_maker.constprop.0+0xe6/0x398 [smc]
[ 136.408495] Kernel panic - not syncing: Fatal exception in interrupt

^^^^^^^^^^

- Jan