[ Upstream commit c6b8b8eb49 ]
The system EID (SEID) is an internal EID used by SMC-D to represent the
s390 physical machine that OS is executing on. On s390 architecture, it
predefined by fixed string and part of cpuid and is enabled regardless
of whether underlay device is virtual ISM or platform firmware ISM.
However on non-s390 architectures where SMC-D can be used with virtual
ISM devices, there is no similar information to identify physical
machines, especially in virtualization scenarios. So in such cases, SEID
is forcibly disabled and the user-defined UEID will be used to represent
the communicable space.
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-and-tested-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dbc153fd3c ]
A crash was found when dumping SMC-D connections. It can be reproduced
by following steps:
- run nginx/wrk test:
smc_run nginx
smc_run wrk -t 16 -c 1000 -d <duration> -H 'Connection: Close' <URL>
- continuously dump SMC-D connections in parallel:
watch -n 1 'smcss -D'
BUG: kernel NULL pointer dereference, address: 0000000000000030
CPU: 2 PID: 7204 Comm: smcss Kdump: loaded Tainted: G E 6.7.0+ #55
RIP: 0010:__smc_diag_dump.constprop.0+0x5e5/0x620 [smc_diag]
Call Trace:
<TASK>
? __die+0x24/0x70
? page_fault_oops+0x66/0x150
? exc_page_fault+0x69/0x140
? asm_exc_page_fault+0x26/0x30
? __smc_diag_dump.constprop.0+0x5e5/0x620 [smc_diag]
? __kmalloc_node_track_caller+0x35d/0x430
? __alloc_skb+0x77/0x170
smc_diag_dump_proto+0xd0/0xf0 [smc_diag]
smc_diag_dump+0x26/0x60 [smc_diag]
netlink_dump+0x19f/0x320
__netlink_dump_start+0x1dc/0x300
smc_diag_handler_dump+0x6a/0x80 [smc_diag]
? __pfx_smc_diag_dump+0x10/0x10 [smc_diag]
sock_diag_rcv_msg+0x121/0x140
? __pfx_sock_diag_rcv_msg+0x10/0x10
netlink_rcv_skb+0x5a/0x110
sock_diag_rcv+0x28/0x40
netlink_unicast+0x22a/0x330
netlink_sendmsg+0x1f8/0x420
__sock_sendmsg+0xb0/0xc0
____sys_sendmsg+0x24e/0x300
? copy_msghdr_from_user+0x62/0x80
___sys_sendmsg+0x7c/0xd0
? __do_fault+0x34/0x160
? do_read_fault+0x5f/0x100
? do_fault+0xb0/0x110
? __handle_mm_fault+0x2b0/0x6c0
__sys_sendmsg+0x4d/0x80
do_syscall_64+0x69/0x180
entry_SYSCALL_64_after_hwframe+0x6e/0x76
It is possible that the connection is in process of being established
when we dump it. Assumed that the connection has been registered in a
link group by smc_conn_create() but the rmb_desc has not yet been
initialized by smc_buf_create(), thus causing the illegal access to
conn->rmb_desc. So fix it by checking before dump.
Fixes: 4b1b7d3b30 ("net/smc: add SMC-D diag support")
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9dbe086c69 ]
A crash was found when dumping SMC-R connections. It can be reproduced
by following steps:
- environment: two RNICs on both sides.
- run SMC-R between two sides, now a SMC_LGR_SYMMETRIC type link group
will be created.
- set the first RNIC down on either side and link group will turn to
SMC_LGR_ASYMMETRIC_LOCAL then.
- run 'smcss -R' and the crash will be triggered.
BUG: kernel NULL pointer dereference, address: 0000000000000010
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 8000000101fdd067 P4D 8000000101fdd067 PUD 10ce46067 PMD 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 3 PID: 1810 Comm: smcss Kdump: loaded Tainted: G W E 6.7.0-rc6+ #51
RIP: 0010:__smc_diag_dump.constprop.0+0x36e/0x620 [smc_diag]
Call Trace:
<TASK>
? __die+0x24/0x70
? page_fault_oops+0x66/0x150
? exc_page_fault+0x69/0x140
? asm_exc_page_fault+0x26/0x30
? __smc_diag_dump.constprop.0+0x36e/0x620 [smc_diag]
smc_diag_dump_proto+0xd0/0xf0 [smc_diag]
smc_diag_dump+0x26/0x60 [smc_diag]
netlink_dump+0x19f/0x320
__netlink_dump_start+0x1dc/0x300
smc_diag_handler_dump+0x6a/0x80 [smc_diag]
? __pfx_smc_diag_dump+0x10/0x10 [smc_diag]
sock_diag_rcv_msg+0x121/0x140
? __pfx_sock_diag_rcv_msg+0x10/0x10
netlink_rcv_skb+0x5a/0x110
sock_diag_rcv+0x28/0x40
netlink_unicast+0x22a/0x330
netlink_sendmsg+0x240/0x4a0
__sock_sendmsg+0xb0/0xc0
____sys_sendmsg+0x24e/0x300
? copy_msghdr_from_user+0x62/0x80
___sys_sendmsg+0x7c/0xd0
? __do_fault+0x34/0x1a0
? do_read_fault+0x5f/0x100
? do_fault+0xb0/0x110
__sys_sendmsg+0x4d/0x80
do_syscall_64+0x45/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
When the first RNIC is set down, the lgr->lnk[0] will be cleared and an
asymmetric link will be allocated in lgr->link[SMC_LINKS_PER_LGR_MAX - 1]
by smc_llc_alloc_alt_link(). Then when we try to dump SMC-R connections
in __smc_diag_dump(), the invalid lgr->lnk[0] will be accessed, resulting
in this issue. So fix it by accessing the right link.
Fixes: f16a7dd5cf ("smc: netlink interface for SMC sockets")
Reported-by: henaumars <henaumars@sina.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=7616
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Link: https://lore.kernel.org/r/1703662835-53416-1-git-send-email-guwen@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e6d71b437a ]
We found a data corruption issue during testing of SMC-R on Redis
applications.
The benchmark has a low probability of reporting a strange error as
shown below.
"Error: Protocol error, got "\xe2" as reply type byte"
Finally, we found that the retrieved error data was as follows:
0xE2 0xD4 0xC3 0xD9 0x04 0x00 0x2C 0x20 0xA6 0x56 0x00 0x16 0x3E 0x0C
0xCB 0x04 0x02 0x01 0x00 0x00 0x20 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0xE2
It is quite obvious that this is a SMC DECLINE message, which means that
the applications received SMC protocol message.
We found that this was caused by the following situations:
client server
¦ clc proposal
------------->
¦ clc accept
<-------------
¦ clc confirm
------------->
wait llc confirm
send llc confirm
¦failed llc confirm
¦ x------
(after 2s)timeout
wait llc confirm rsp
wait decline
(after 1s) timeout
(after 2s) timeout
¦ decline
-------------->
¦ decline
<--------------
As a result, a decline message was sent in the implementation, and this
message was read from TCP by the already-fallback connection.
This patch double the client timeout as 2x of the server value,
With this simple change, the Decline messages should never cross or
collide (during Confirm link timeout).
This issue requires an immediate solution, since the protocol updates
involve a more long-term solution.
Fixes: 0fb0b02bd6 ("net/smc: adapt SMC client code to use the LLC flow")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aa96fbd6d7 ]
Note that we always hold a reference to sock when attempting
to submit close_work. Therefore, if we have successfully
canceled close_work from pending, we MUST release that reference
to avoid potential leaks.
Fixes: 42bfba9eaa ("net/smc: immediate termination for SMCD link groups")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c5bf605ba4 ]
This patch re-fix the issues mentioned by commit 22a825c541
("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()").
Blocking sending message do solve the issues though, but it also
prevents the peer to receive the final message. Besides, in logic,
whether the sndbuf_desc is NULL or not have no impact on the processing
of cdc message sending.
Hence that, this patch allows the cdc message sending but to check the
sndbuf_desc with care in smc_cdc_tx_handler().
Fixes: 22a825c541 ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5211c97294 ]
Considering scenario:
smc_cdc_rx_handler
__smc_release
sock_set_flag
smc_close_active()
sock_set_flag
__set_bit(DEAD) __set_bit(DONE)
Dues to __set_bit is not atomic, the DEAD or DONE might be lost.
if the DEAD flag lost, the state SMC_CLOSED will be never be reached
in smc_close_passive_work:
if (sock_flag(sk, SOCK_DEAD) &&
smc_close_sent_any_close(conn)) {
sk->sk_state = SMC_CLOSED;
} else {
/* just shutdown, but not yet closed locally */
sk->sk_state = SMC_APPFINCLOSEWAIT;
}
Replace sock_set_flags or __set_bit to set_bit will fix this problem.
Since set_bit is atomic.
Fixes: b38d732477 ("smc: socket closing and linkgroup cleanup")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c68681ae46 ]
If the netdevice is within a container and communicates externally
through network technologies such as VxLAN, we won't be able to find
routing information in the init_net namespace. To address this issue,
we need to add a struct net parameter to the smc_ib_find_route function.
This allow us to locate the routing information within the corresponding
net namespace, ensuring the correct completion of the SMC CLC interaction.
Fixes: e5c4744cfb ("net/smc: add SMC-Rv2 connection establishment")
Signed-off-by: Albert Huang <huangjie.albert@bytedance.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Link: https://lore.kernel.org/r/20231011074851.95280-1-huangjie.albert@bytedance.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 4abbd2e3c1 upstream.
In the smc_listen_work(), if smc_listen_prfx_check() failed,
the real reason: SMC_CLC_DECL_DIFFPREFIX was dropped, and
SMC_CLC_DECL_NOSMCDEV was returned.
Althrough this is also kind of SMC_CLC_DECL_NOSMCDEV, but return
the real reason is much friendly for debugging.
Fixes: e49300a6bf ("net/smc: add listen processing for SMC-Rv2")
Signed-off-by: Dust Li <dust.li@linux.alibaba.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Link: https://lore.kernel.org/r/20231012123729.29307-1-dust.li@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a950a5921d ]
SMC_STAT_PAYLOAD_SUB(_smc_stats, _tech, key, _len, _rc) will calculate
wrong bucket positions for payloads of exactly 4096 bytes and
(1 << (m + 12)) bytes, with m == SMC_BUF_MAX - 1.
Intended bucket distribution:
Assume l == size of payload, m == SMC_BUF_MAX - 1.
Bucket 0 : 0 < l <= 2^13
Bucket n, 1 <= n <= m-1 : 2^(n+12) < l <= 2^(n+13)
Bucket m : l > 2^(m+12)
Current solution:
_pos = fls64((l) >> 13)
[...]
_pos = (_pos < m) ? ((l == 1 << (_pos + 12)) ? _pos - 1 : _pos) : m
For l == 4096, _pos == -1, but should be _pos == 0.
For l == (1 << (m + 12)), _pos == m, but should be _pos == m - 1.
In order to avoid special treatment of these corner cases, the
calculation is adjusted. The new solution first subtracts the length by
one, and then calculates the correct bucket by shifting accordingly,
i.e. _pos = fls64((l - 1) >> 13), l > 0.
This not only fixes the issues named above, but also makes the whole
bucket assignment easier to follow.
Same is done for SMC_STAT_RMB_SIZE_SUB(_smc_stats, _tech, k, _len),
where the calculation of the bucket position is similar to the one
named above.
Fixes: e0e4b8fa53 ("net/smc: Add SMC statistics support")
Suggested-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Nils Hoppmann <niho@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6912e72483 ]
In the macro SMC_STAT_SERV_SUCC_INC, the smcd_version is used
to determin whether to increase the v1 statistic or the v2
statistic. It is correct for SMCD. But for SMCR, smcr_version
should be used.
Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bc1fb82ae1 ]
sk_getsockopt() runs locklessly. This means sk->sk_lingertime
can be read while other threads are changing its value.
Other reads also happen without socket lock being held,
and must be annotated.
Remove preprocessor logic using BITS_PER_LONG, compilers
are smart enough to figure this by themselves.
v2: fixed a clang W=1 (-Wtautological-constant-out-of-range-compare) warning
(Jakub)
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 833bac7ec3 ]
Commit 0227f058aa ("net/smc: Unbind r/w buffer size from clcsock
and make them tunable") introduced the net.smc.rmem and net.smc.wmem
sysctls to specify the size of buffers to be used for SMC type
connections. This created a regression for users that specified the
buffer size via setsockopt() as the effective buffer size was now
doubled.
Re-introduce the division by 2 in the SMC buffer create code and level
this out by duplicating the net.smc.[rw]mem values used for initializing
sk_rcvbuf/sk_sndbuf at socket creation time. This gives users of both
methods (setsockopt or sysctl) the effective buffer size that they
expect.
Initialize net.smc.[rw]mem from its own constant of 64kB, respectively.
Internal performance tests show that this value is a good compromise
between throughput/latency and memory consumption. Also, this decouples
it from any tuning that was done to net.ipv4.tcp_[rw]mem[1] before the
module for SMC protocol was loaded. Check that no more than INT_MAX / 2
is assigned to net.smc.[rw]mem, in order to avoid any overflow condition
when that is doubled for use in sk_sndbuf or sk_rcvbuf.
While at it, drop the confusing sk_buf_size variable from
__smc_buf_create and name "compressed" buffer size variables more
consistently.
Background:
Before the commit mentioned above, SMC's buffer allocator in
__smc_buf_create() always used half of the sockets' sk_rcvbuf/sk_sndbuf
value as initial value to search for appropriate buffers. If the search
resorted to using a bigger buffer when all buffers of the specified
size were busy, the duplicate of the used effective buffer size is
stored back to sk_rcvbuf/sk_sndbuf.
When available, buffers of exactly the size that a user had specified as
input to setsockopt() were used, despite setsockopt()'s documentation in
"man 7 socket" talking of a mandatory duplication:
[...]
SO_SNDBUF
Sets or gets the maximum socket send buffer in bytes.
The kernel doubles this value (to allow space for book‐
keeping overhead) when it is set using setsockopt(2),
and this doubled value is returned by getsockopt(2).
The default value is set by the
/proc/sys/net/core/wmem_default file and the maximum
allowed value is set by the /proc/sys/net/core/wmem_max
file. The minimum (doubled) value for this option is
2048.
[...]
Fixes: 0227f058aa ("net/smc: Unbind r/w buffer size from clcsock and make them tunable")
Co-developed-by: Jan Karcher <jaka@linux.ibm.com>
Signed-off-by: Jan Karcher <jaka@linux.ibm.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aff7bfed90 ]
It's clear that rmbs_lock and sndbufs_lock are aims to protect the
rmbs list or the sndbufs list.
During connection establieshment, smc_buf_get_slot() will always
be invoked, and it only performs read semantics in rmbs list and
sndbufs list.
Based on the above considerations, we replace mutex with rw_semaphore.
Only smc_buf_get_slot() use down_read() to allow smc_buf_get_slot()
run concurrently, other part use down_write() to keep exclusive
semantics.
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 833bac7ec3 ("net/smc: Fix setsockopt and sysctl to specify same buffer size again")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 30c3c4a449 upstream.
Tuning of the effective buffer size through setsockopts was working for
SMC traffic only but not for TCP fall-back connections even before
commit 0227f058aa ("net/smc: Unbind r/w buffer size from clcsock and
make them tunable"). That change made it apparent that TCP fall-back
connections would use net.smc.[rw]mem as buffer size instead of
net.ipv4_tcp_[rw]mem.
Amend the code that copies attributes between the (TCP) clcsock and the
SMC socket and adjust buffer sizes appropriately:
- Copy over sk_userlocks so that both sockets agree on whether tuning
via setsockopt is active.
- When falling back to TCP use sk_sndbuf or sk_rcvbuf as specified with
setsockopt. Otherwise, use the sysctl value for TCP/IPv4.
- Likewise, use either values from setsockopt or from sysctl for SMC
(duplicated) on successful SMC connect.
In smc_tcp_listen_work() drop the explicit copy of buffer sizes as that
is taken care of by the attribute copy.
Fixes: 0227f058aa ("net/smc: Unbind r/w buffer size from clcsock and make them tunable")
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3c5b4d69c3 ]
sk->sk_mark is often read while another thread could change the value.
Fixes: 4a19ec5800 ("[NET]: Introducing socket mark socket option.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c308e9ec00 ]
SMCRv1 has a similar issue to SMCRv2 (see link below) that may access
invalid MRs of RMBs when construct LLC ADD LINK CONT messages.
BUG: kernel NULL pointer dereference, address: 0000000000000014
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 5 PID: 48 Comm: kworker/5:0 Kdump: loaded Tainted: G W E 6.4.0-rc3+ #49
Workqueue: events smc_llc_add_link_work [smc]
RIP: 0010:smc_llc_add_link_cont+0x160/0x270 [smc]
RSP: 0018:ffffa737801d3d50 EFLAGS: 00010286
RAX: ffff964f82144000 RBX: ffffa737801d3dd8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff964f81370c30
RBP: ffffa737801d3dd4 R08: ffff964f81370000 R09: ffffa737801d3db0
R10: 0000000000000001 R11: 0000000000000060 R12: ffff964f82e70000
R13: ffff964f81370c38 R14: ffffa737801d3dd3 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff9652bfd40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000014 CR3: 000000008fa20004 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
smc_llc_srv_rkey_exchange+0xa7/0x190 [smc]
smc_llc_srv_add_link+0x3ae/0x5a0 [smc]
smc_llc_add_link_work+0xb8/0x140 [smc]
process_one_work+0x1e5/0x3f0
worker_thread+0x4d/0x2f0
? __pfx_worker_thread+0x10/0x10
kthread+0xe5/0x120
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>
When an alernate RNIC is available in system, SMC will try to add a new
link based on the RNIC for resilience. All the RMBs in use will be mapped
to the new link. Then the RMBs' MRs corresponding to the new link will
be filled into LLC messages. For SMCRv1, they are ADD LINK CONT messages.
However smc_llc_add_link_cont() may mistakenly access to unused RMBs which
haven't been mapped to the new link and have no valid MRs, thus causing a
crash. So this patch fixes it.
Fixes: 87f88cda21 ("net/smc: rkey processing for a new link as SMC client")
Link: https://lore.kernel.org/r/1685101741-74826-3-git-send-email-guwen@linux.alibaba.com
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 71c6aa0305 ]
We encountered a crash when using SMCRv2. It is caused by a logical
error in smc_llc_fill_ext_v2().
BUG: kernel NULL pointer dereference, address: 0000000000000014
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 7 PID: 453 Comm: kworker/7:4 Kdump: loaded Tainted: G W E 6.4.0-rc3+ #44
Workqueue: events smc_llc_add_link_work [smc]
RIP: 0010:smc_llc_fill_ext_v2+0x117/0x280 [smc]
RSP: 0018:ffffacb5c064bd88 EFLAGS: 00010282
RAX: ffff9a6bc1c3c02c RBX: ffff9a6be3558000 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000000a
RBP: ffffacb5c064bdb8 R08: 0000000000000040 R09: 000000000000000c
R10: ffff9a6bc0910300 R11: 0000000000000002 R12: 0000000000000000
R13: 0000000000000002 R14: ffff9a6bc1c3c02c R15: ffff9a6be3558250
FS: 0000000000000000(0000) GS:ffff9a6eefdc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000014 CR3: 000000010b078003 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
smc_llc_send_add_link+0x1ae/0x2f0 [smc]
smc_llc_srv_add_link+0x2c9/0x5a0 [smc]
? cc_mkenc+0x40/0x60
smc_llc_add_link_work+0xb8/0x140 [smc]
process_one_work+0x1e5/0x3f0
worker_thread+0x4d/0x2f0
? __pfx_worker_thread+0x10/0x10
kthread+0xe5/0x120
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>
When an alernate RNIC is available in system, SMC will try to add a new
link based on the RNIC for resilience. All the RMBs in use will be mapped
to the new link. Then the RMBs' MRs corresponding to the new link will be
filled into SMCRv2 LLC ADD LINK messages.
However, smc_llc_fill_ext_v2() mistakenly accesses to unused RMBs which
haven't been mapped to the new link and have no valid MRs, thus causing
a crash. So this patch fixes the logic.
Fixes: b4ba4652b3 ("net/smc: extend LLC layer for SMC-Rv2")
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b24aa141c2 ]
When finding the first RMB of link group, it should start from the
current RMB list whose index is 0. So fix it.
Fixes: b4ba4652b3 ("net/smc: extend LLC layer for SMC-Rv2")
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 3511227167 upstream.
We found a crash when using SMCRv2 with 2 Mellanox ConnectX-4. It
can be reproduced by:
- smc_run nginx
- smc_run wrk -t 32 -c 500 -d 30 http://<ip>:<port>
BUG: kernel NULL pointer dereference, address: 0000000000000014
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 8000000108713067 P4D 8000000108713067 PUD 151127067 PMD 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 4 PID: 2441 Comm: kworker/4:249 Kdump: loaded Tainted: G W E 6.4.0-rc1+ #42
Workqueue: smc_hs_wq smc_listen_work [smc]
RIP: 0010:smc_clc_send_confirm_accept+0x284/0x580 [smc]
RSP: 0018:ffffb8294b2d7c78 EFLAGS: 00010a06
RAX: ffff8f1873238880 RBX: ffffb8294b2d7dc8 RCX: 0000000000000000
RDX: 00000000000000b4 RSI: 0000000000000001 RDI: 0000000000b40c00
RBP: ffffb8294b2d7db8 R08: ffff8f1815c5860c R09: 0000000000000000
R10: 0000000000000400 R11: 0000000000000000 R12: ffff8f1846f56180
R13: ffff8f1815c5860c R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8f1aefd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000014 CR3: 00000001027a0001 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
? mlx5_ib_map_mr_sg+0xa1/0xd0 [mlx5_ib]
? smcr_buf_map_link+0x24b/0x290 [smc]
? __smc_buf_create+0x4ee/0x9b0 [smc]
smc_clc_send_accept+0x4c/0xb0 [smc]
smc_listen_work+0x346/0x650 [smc]
? __schedule+0x279/0x820
process_one_work+0x1e5/0x3f0
worker_thread+0x4d/0x2f0
? __pfx_worker_thread+0x10/0x10
kthread+0xe5/0x120
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>
During the CLC handshake, server sequentially tries available SMCRv2
and SMCRv1 devices in smc_listen_work().
If an SMCRv2 device is found. SMCv2 based link group and link will be
assigned to the connection. Then assumed that some buffer assignment
errors happen later in the CLC handshake, such as RMB registration
failure, server will give up SMCRv2 and try SMCRv1 device instead. But
the resources assigned to the connection won't be reset.
When server tries SMCRv1 device, the connection creation process will
be executed again. Since conn->lnk has been assigned when trying SMCRv2,
it will not be set to the correct SMCRv1 link in
smcr_lgr_conn_assign_link(). So in such situation, conn->lgr points to
correct SMCRv1 link group but conn->lnk points to the SMCRv2 link
mistakenly.
Then in smc_clc_send_confirm_accept(), conn->rmb_desc->mr[link->link_idx]
will be accessed. Since the link->link_idx is not correct, the related
MR may not have been initialized, so crash happens.
| Try SMCRv2 device first
| |-> conn->lgr: assign existed SMCRv2 link group;
| |-> conn->link: assign existed SMCRv2 link (link_idx may be 1 in SMC_LGR_SYMMETRIC);
| |-> sndbuf & RMB creation fails, quit;
|
| Try SMCRv1 device then
| |-> conn->lgr: create SMCRv1 link group and assign;
| |-> conn->link: keep SMCRv2 link mistakenly;
| |-> sndbuf & RMB creation succeed, only RMB->mr[link_idx = 0]
| initialized.
|
| Then smc_clc_send_confirm_accept() accesses
| conn->rmb_desc->mr[conn->link->link_idx, which is 1], then crash.
v
This patch tries to fix this by cleaning conn->lnk before assigning
link. In addition, it is better to reset the connection and clean the
resources assigned if trying SMCRv2 failed in buffer creation or
registration.
Fixes: e49300a6bf ("net/smc: add listen processing for SMC-Rv2")
Link: https://lore.kernel.org/r/20220523055056.2078994-1-liuyacan@corp.netease.com/
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 22a825c541 ]
When performing a stress test on SMC-R by rmmod mlx5_ib driver
during the wrk/nginx test, we found that there is a probability
of triggering a panic while terminating all link groups.
This issue dues to the race between smc_smcr_terminate_all()
and smc_buf_create().
smc_smcr_terminate_all
smc_buf_create
/* init */
conn->sndbuf_desc = NULL;
...
__smc_lgr_terminate
smc_conn_kill
smc_close_abort
smc_cdc_get_slot_and_msg_send
__softirqentry_text_start
smc_wr_tx_process_cqe
smc_cdc_tx_handler
READ(conn->sndbuf_desc->len);
/* panic dues to NULL sndbuf_desc */
conn->sndbuf_desc = xxx;
This patch tries to fix the issue by always to check the sndbuf_desc
before send any cdc msg, to make sure that no null pointer is
seen during cqe processing.
Fixes: 0b29ec6436 ("net/smc: immediate termination for SMCR link groups")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Link: https://lore.kernel.org/r/1678263432-17329-1-git-send-email-alibuda@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ce7ca79471 ]
Before determining whether the msg has unsupported options, it has been
prematurely terminated by the wrong status check.
For the application, the general usages of MSG_FASTOPEN likes
fd = socket(...)
/* rather than connect */
sendto(fd, data, len, MSG_FASTOPEN)
Hence, We need to check the flag before state check, because the sock
state here is always SMC_INIT when applications tries MSG_FASTOPEN.
Once we found unsupported options, fallback it to TCP.
Fixes: ee9dfbef02 ("net/smc: handle sockopts forcing fallback")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
v2 -> v1: Optimize code style
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 475f9ff63e ]
There is a certain probability that following
exceptions will occur in the wrk benchmark test:
Running 10s test @ http://11.213.45.6:80
8 threads and 64 connections
Thread Stats Avg Stdev Max +/- Stdev
Latency 3.72ms 13.94ms 245.33ms 94.17%
Req/Sec 1.96k 713.67 5.41k 75.16%
155262 requests in 10.10s, 23.10MB read
Non-2xx or 3xx responses: 3
We will find that the error is HTTP 400 error, which is a serious
exception in our test, which means the application data was
corrupted.
Consider the following scenarios:
CPU0 CPU1
buf_desc->used = 0;
cmpxchg(buf_desc->used, 0, 1)
deal_with(buf_desc)
memset(buf_desc->cpu_addr,0);
This will cause the data received by a victim connection to be cleared,
thus triggering an HTTP 400 error in the server.
This patch exchange the order between clear used and memset, add
barrier to ensure memory consistency.
Fixes: 1c5526968e ("net/smc: Clear memory when release and reuse buffer")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e40b801b36 ]
There is a certain chance to trigger the following panic:
PID: 5900 TASK: ffff88c1c8af4100 CPU: 1 COMMAND: "kworker/1:48"
#0 [ffff9456c1cc79a0] machine_kexec at ffffffff870665b7
#1 [ffff9456c1cc79f0] __crash_kexec at ffffffff871b4c7a
#2 [ffff9456c1cc7ab0] crash_kexec at ffffffff871b5b60
#3 [ffff9456c1cc7ac0] oops_end at ffffffff87026ce7
#4 [ffff9456c1cc7ae0] page_fault_oops at ffffffff87075715
#5 [ffff9456c1cc7b58] exc_page_fault at ffffffff87ad0654
#6 [ffff9456c1cc7b80] asm_exc_page_fault at ffffffff87c00b62
[exception RIP: ib_alloc_mr+19]
RIP: ffffffffc0c9cce3 RSP: ffff9456c1cc7c38 RFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000004
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88c1ea281d00 R8: 000000020a34ffff R9: ffff88c1350bbb20
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000010 R14: ffff88c1ab040a50 R15: ffff88c1ea281d00
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#7 [ffff9456c1cc7c60] smc_ib_get_memory_region at ffffffffc0aff6df [smc]
#8 [ffff9456c1cc7c88] smcr_buf_map_link at ffffffffc0b0278c [smc]
#9 [ffff9456c1cc7ce0] __smc_buf_create at ffffffffc0b03586 [smc]
The reason here is that when the server tries to create a second link,
smc_llc_srv_add_link() has no protection and may add a new link to
link group. This breaks the security environment protected by
llc_conf_mutex.
Fixes: 2d2209f201 ("net/smc: first part of add link processing as SMC server")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit de4eda9de2 ]
READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.
Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Stable-dep-of: 6dd88fd59d ("vhost-scsi: unbreak any layout for response")
Signed-off-by: Sasha Levin <sashal@kernel.org>
In smc_init(), register_pernet_subsys(&smc_net_stat_ops) is called
without any error handling.
If it fails, registering of &smc_net_ops won't be reverted.
And if smc_nl_init() fails, &smc_net_stat_ops itself won't be reverted.
This leaves wild ops in subsystem linkedlist and when another module
tries to call register_pernet_operations() it triggers page fault:
BUG: unable to handle page fault for address: fffffbfff81b964c
RIP: 0010:register_pernet_operations+0x1b9/0x5f0
Call Trace:
<TASK>
register_pernet_subsys+0x29/0x40
ebtables_init+0x58/0x1000 [ebtables]
...
Fixes: 194730a9be ("net/smc: Make SMC statistics network namespace aware")
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Link: https://lore.kernel.org/r/20221101093722.127223-1-chenzhongjin@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If smc_wr_alloc_lgr_mem() fails then return an error code. Don't return
success.
Fixes: 8799e310fb ("net/smc: add v2 support to the work request layer")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, SMC uses smc->sk.sk_{rcv|snd}buf to create buffers for
send buffer and RMB. And the values of buffer size are from tcp_{w|r}mem
in clcsock.
The buffer size from TCP socket doesn't fit SMC well. Generally, buffers
are usually larger than TCP for SMC-R/-D to get higher performance, for
they are different underlay devices and paths.
So this patch unbinds buffer size from TCP, and introduces two sysctl
knobs to tune them independently. Also, these knobs are per net
namespace and work for containers.
Signed-off-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
SMC-R tests the viability of link by sending out TEST_LINK LLC
messages over RoCE fabric when connections on link have been
idle for a time longer than keepalive interval (testlink time).
But using tcp_keepalive_time as testlink time maybe not quite
suitable because it is default no less than two hours[1], which
is too long for single link to find peer dead. The active host
will still use peer-dead link (QP) sending messages, and can't
find out until get IB_WC_RETRY_EXC_ERR error CQEs, which takes
more time than TEST_LINK timeout (SMC_LLC_WAIT_TIME) normally.
So this patch introduces a independent sysctl for SMC-R to set
link keepalive time, in order to detect link down in time. The
default value is 30 seconds.
[1] https://www.rfc-editor.org/rfc/rfc1122#page-101
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
There might be a potential race between SMC-R buffer map and
link group termination.
smc_smcr_terminate_all() | smc_connect_rdma()
--------------------------------------------------------------
| smc_conn_create()
for links in smcibdev |
schedule links down |
| smc_buf_create()
| \- smcr_buf_map_usable_links()
| \- no usable links found,
| (rmb->mr = NULL)
|
| smc_clc_send_confirm()
| \- access conn->rmb_desc->mr[]->rkey
| (panic)
During reboot and IB device module remove, all links will be set
down and no usable links remain in link groups. In such situation
smcr_buf_map_usable_links() should return an error and stop the
CLC flow accessing to uninitialized mr.
Fixes: b9247544c1 ("net/smc: convert static link ID instances to support multiple links")
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Link: https://lore.kernel.org/r/1663656189-32090-1-git-send-email-guwen@linux.alibaba.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
drivers/net/ethernet/freescale/fec.h
7d650df99d ("net: fec: add pm_qos support on imx6q platform")
40c79ce13b ("net: fec: add stop mode support for imx8 platform")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
For passive connections, the refcount increment has been done in
smc_clcsock_accept()-->smc_sock_alloc().
Fixes: 3b2dec2603 ("net/smc: restructure client and server code in af_smc")
Signed-off-by: Yacan Liu <liuyacan@corp.netease.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220830152314.838736-1-liuyacan@corp.netease.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
We had historically not checked that genlmsghdr.reserved
is 0 on input which prevents us from using those precious
bytes in the future.
One use case would be to extend the cmd field, which is
currently just 8 bits wide and 256 is not a lot of commands
for some core families.
To make sure that new families do the right thing by default
put the onus of opting out of validation on existing families.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel)
Signed-off-by: David S. Miller <davem@davemloft.net>
Previously, the smc and smc_diag modules were automatically loaded as
dependencies of the ism module whenever an ISM device was present.
With the pending rework of the ISM API, the smc module will no longer
automatically be loaded in presence of an ISM device. Usage of an AF_SMC
socket will still trigger loading of the smc modules, but usage of a
netlink socket will not.
This is addressed by setting the correct module aliases.
Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Wenjia Zhang < wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the DMBE bits, which are passed on individually in ism_move() as
parameter idx, available to the receiver.
Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Wenjia Zhang < wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reworked signature of the function to retrieve the system EID: No plausible
reason to use a double pointer. And neither to pass in the device as an
argument, as this identifier is by definition per system, not per device.
Plus some minor consistency edits.
Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Wenjia Zhang < wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This struct is used in a single place only, and its usage generates
inefficient code. Time to clean up!
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-and-tested-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Wenjia Zhang < wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While reading sysctl_tcp_keepalive_(time|probes|intvl), they can be changed
concurrently. Thus, we need to add READ_ONCE() to their readers.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend SMC-R link group netlink attribute SMC_GEN_LGR_SMCR.
Introduce SMC_NLA_LGR_R_BUF_TYPE to show the buffer type of
SMC-R link group.
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On long-running enterprise production servers, high-order contiguous
memory pages are usually very rare and in most cases we can only get
fragmented pages.
When replacing TCP with SMC-R in such production scenarios, attempting
to allocate high-order physically contiguous sndbufs and RMBs may result
in frequent memory compaction, which will cause unexpected hung issue
and further stability risks.
So this patch is aimed to allow SMC-R link group to use virtually
contiguous sndbufs and RMBs to avoid potential issues mentioned above.
Whether to use physically or virtually contiguous buffers can be set
by sysctl smcr_buf_type.
Note that using virtually contiguous buffers will bring an acceptable
performance regression, which can be mainly divided into two parts:
1) regression in data path, which is brought by additional address
translation of sndbuf by RNIC in Tx. But in general, translating
address through MTT is fast.
Taking 256KB sndbuf and RMB as an example, the comparisons in qperf
latency and bandwidth test with physically and virtually contiguous
buffers are as follows:
- client:
smc_run taskset -c <cpu> qperf <server> -oo msg_size:1:64K:*2\
-t 5 -vu tcp_{bw|lat}
- server:
smc_run taskset -c <cpu> qperf
[latency]
msgsize tcp smcr smcr-use-virt-buf
1 11.17 us 7.56 us 7.51 us (-0.67%)
2 10.65 us 7.74 us 7.56 us (-2.31%)
4 11.11 us 7.52 us 7.59 us ( 0.84%)
8 10.83 us 7.55 us 7.51 us (-0.48%)
16 11.21 us 7.46 us 7.51 us ( 0.71%)
32 10.65 us 7.53 us 7.58 us ( 0.61%)
64 10.95 us 7.74 us 7.80 us ( 0.76%)
128 11.14 us 7.83 us 7.87 us ( 0.47%)
256 10.97 us 7.94 us 7.92 us (-0.28%)
512 11.23 us 7.94 us 8.20 us ( 3.25%)
1024 11.60 us 8.12 us 8.20 us ( 0.96%)
2048 14.04 us 8.30 us 8.51 us ( 2.49%)
4096 16.88 us 9.13 us 9.07 us (-0.64%)
8192 22.50 us 10.56 us 11.22 us ( 6.26%)
16384 28.99 us 12.88 us 13.83 us ( 7.37%)
32768 40.13 us 16.76 us 16.95 us ( 1.16%)
65536 68.70 us 24.68 us 24.85 us ( 0.68%)
[bandwidth]
msgsize tcp smcr smcr-use-virt-buf
1 1.65 MB/s 1.59 MB/s 1.53 MB/s (-3.88%)
2 3.32 MB/s 3.17 MB/s 3.08 MB/s (-2.67%)
4 6.66 MB/s 6.33 MB/s 6.09 MB/s (-3.85%)
8 13.67 MB/s 13.45 MB/s 11.97 MB/s (-10.99%)
16 25.36 MB/s 27.15 MB/s 24.16 MB/s (-11.01%)
32 48.22 MB/s 54.24 MB/s 49.41 MB/s (-8.89%)
64 106.79 MB/s 107.32 MB/s 99.05 MB/s (-7.71%)
128 210.21 MB/s 202.46 MB/s 201.02 MB/s (-0.71%)
256 400.81 MB/s 416.81 MB/s 393.52 MB/s (-5.59%)
512 746.49 MB/s 834.12 MB/s 809.99 MB/s (-2.89%)
1024 1292.33 MB/s 1641.96 MB/s 1571.82 MB/s (-4.27%)
2048 2007.64 MB/s 2760.44 MB/s 2717.68 MB/s (-1.55%)
4096 2665.17 MB/s 4157.44 MB/s 4070.76 MB/s (-2.09%)
8192 3159.72 MB/s 4361.57 MB/s 4270.65 MB/s (-2.08%)
16384 4186.70 MB/s 4574.13 MB/s 4501.17 MB/s (-1.60%)
32768 4093.21 MB/s 4487.42 MB/s 4322.43 MB/s (-3.68%)
65536 4057.14 MB/s 4735.61 MB/s 4555.17 MB/s (-3.81%)
2) regression in buffer initialization and destruction path, which is
brought by additional MR operations of sndbufs. But thanks to link
group buffer reuse mechanism, the impact of this kind of regression
decreases as times of buffer reuse increases.
Taking 256KB sndbuf and RMB as an example, latency of some key SMC-R
buffer-related function obtained by bpftrace are as follows:
Function Phys-bufs Virt-bufs
smcr_new_buf_create() 67154 ns 79164 ns
smc_ib_buf_map_sg() 525 ns 928 ns
smc_ib_get_memory_region() 162294 ns 161191 ns
smc_wr_reg_send() 9957 ns 9635 ns
smc_ib_put_memory_region() 203548 ns 198374 ns
smc_ib_buf_unmap_sg() 508 ns 1158 ns
------------
Test environment notes:
1. Above tests run on 2 VMs within the same Host.
2. The NIC is ConnectX-4Lx, using SRIOV and passing through 2 VFs to
the each VM respectively.
3. VMs' vCPUs are binded to different physical CPUs, and the binded
physical CPUs are isolated by `isolcpus=xxx` cmdline.
4. NICs' queue number are set to 1.
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces a new SMC-R specific element buf_type
in struct smc_link_group, for recording the value of sysctl
smcr_buf_type when link group is created.
New created link group will create and reuse buffers of the
type specified by buf_type.
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet