linux/net/smc
Li RongQing e7bed88e05 net/smc: remove unneeded atomic operations in smc_tx_sndbuf_nonempty
The commit dcd2cf5f2f ("net/smc: add autocorking support") adds an
atomic variable tx_pushing in smc_connection to make sure only one can
send to let it cork more and save CDC slot. since smc_tx_pending can be
called in the soft IRQ without checking sock_owned_by_user() at that
time, which would cause a race condition because bh_lock_sock() did
not honor sock_lock()

After commit 6b88af839d ("net/smc: don't send in the BH context if
sock_owned_by_user"), the transmission is deferred to when sock_lock()
is held by the user. Therefore, we no longer need tx_pending to hold
message.

So remove atomic variable tx_pushing and its operation, and
smc_tx_sndbuf_nonempty becomes a wrapper of __smc_tx_sndbuf_nonempty,
so rename __smc_tx_sndbuf_nonempty back to smc_tx_sndbuf_nonempty

Suggested-by: Alexandra Winter <wintera@linux.ibm.com>
Co-developed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>

diff v4: remove atomic variable tx_pushing
diff v3: improvements in the commit body and comments
diff v2: fix a typo in commit body and add net-next subject-prefix

 net/smc/smc.h    |  1 -
 net/smc/smc_tx.c | 30 +-----------------------------
 2 files changed, 1 insertion(+), 30 deletions(-)

Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-24 15:00:47 +00:00
..
af_smc.c net/smc: add sysctl for max links per lgr for SMC-R v2.1 2023-11-24 12:13:14 +00:00
Kconfig net/smc: Fix dependency of SMC on ISM 2023-10-10 11:51:41 +02:00
Makefile net/smc: fix compile warning for smc_sysctl 2022-03-07 11:59:17 +00:00
smc_cdc.c net/smc: allow cdc msg send rather than drop it with NULL sndbuf_desc 2023-11-06 10:01:07 +00:00
smc_cdc.h net/smc: fix kernel panic caused by race of smc_sock 2021-12-28 12:42:45 +00:00
smc_clc.c net/smc: add sysctl for max conns per lgr for SMC-R v2.1 2023-11-24 12:13:14 +00:00
smc_clc.h net/smc: add sysctl for max links per lgr for SMC-R v2.1 2023-11-24 12:13:14 +00:00
smc_close.c net/smc: put sk reference if close work was canceled 2023-11-06 10:01:07 +00:00
smc_close.h net/smc: remove close abort worker 2019-10-22 11:23:44 -07:00
smc_core.c net/smc: use smc_lgr_list.lock to protect smc_lgr_list.list iterate in smcr_port_add 2023-09-10 19:31:42 +01:00
smc_core.h net/smc: support max links per lgr negotiation in clc handshake 2023-08-19 12:46:53 +01:00
smc_diag.c net: fill in MODULE_DESCRIPTION()s for SOCK_DIAG modules 2023-11-19 20:09:13 +00:00
smc_ib.c net/smc: fix smc clc failed issue when netdevice not in init_net 2023-10-13 16:52:02 -07:00
smc_ib.h net/smc: fix smc clc failed issue when netdevice not in init_net 2023-10-13 16:52:02 -07:00
smc_ism.c net/smc: Introduce explicit check for v2 support 2023-03-15 08:18:35 +00:00
smc_ism.h net/smc: Register SMC-D as ISM client 2023-01-25 09:46:48 +00:00
smc_llc.c net/smc: support max links per lgr negotiation in clc handshake 2023-08-19 12:46:53 +01:00
smc_llc.h net/smc: Introduce a specific sysctl for TEST_LINK time 2022-09-22 12:58:21 +02:00
smc_netlink.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
smc_netlink.h net/smc: add support for user defined EIDs 2021-09-14 12:49:10 +01:00
smc_netns.h net/smc: introduce list of pnetids for Ethernet devices 2020-09-28 15:19:03 -07:00
smc_pnet.c net/smc: De-tangle ism and smc device initialization 2023-01-25 09:46:49 +00:00
smc_pnet.h net/smc: Use a mutex for locking "struct smc_pnettable" 2022-02-24 09:09:33 -08:00
smc_rx.c net: deal with most data-races in sk_wait_event() 2023-05-10 10:03:32 +01:00
smc_rx.h smc: add support for splice() 2018-05-04 11:45:06 -04:00
smc_stats.c smc: Drop smc_sendpage() in favour of smc_sendmsg() + MSG_SPLICE_PAGES 2023-06-24 15:50:12 -07:00
smc_stats.h net/smc: Fix pos miscalculation in statistics 2023-10-11 10:36:35 +01:00
smc_sysctl.c net/smc: add sysctl for max conns per lgr for SMC-R v2.1 2023-11-24 12:13:14 +00:00
smc_sysctl.h net/smc: add sysctl for max conns per lgr for SMC-R v2.1 2023-11-24 12:13:14 +00:00
smc_tracepoint.c net/smc: Introduce tracepoint for smcr link down 2021-11-01 13:39:14 +00:00
smc_tracepoint.h net/smc: Add net namespace for tracepoints 2022-01-02 12:07:39 +00:00
smc_tx.c net/smc: remove unneeded atomic operations in smc_tx_sndbuf_nonempty 2023-11-24 15:00:47 +00:00
smc_tx.h smc: Drop smc_sendpage() in favour of smc_sendmsg() + MSG_SPLICE_PAGES 2023-06-24 15:50:12 -07:00
smc_wr.c net/smc: Use percpu ref for wr tx reference 2023-03-17 08:59:01 +00:00
smc_wr.h net/smc: Use percpu ref for wr tx reference 2023-03-17 08:59:01 +00:00
smc.h net/smc: remove unneeded atomic operations in smc_tx_sndbuf_nonempty 2023-11-24 15:00:47 +00:00