mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-27 21:03:32 +00:00
3538026230
[ Upstream commit ea785a1a57 ]
According to the man page of TCP_CORK [1], if set, don't send out
partial frames. All queued partial frames are sent when option is
cleared again.
When applications call setsockopt to disable TCP_CORK, this call is
protected by lock_sock(), and tries to mod_delayed_work() to 0, in order
to send pending data right now. However, the delayed work smc_tx_work is
also protected by lock_sock(). There introduces lock contention for
sending data.
To fix it, send pending data directly which acts like TCP, without
lock_sock() protected in the context of setsockopt (already lock_sock()ed),
and cancel unnecessary dealyed work, which is protected by lock.
[1] https://linux.die.net/man/7/tcp
Signed-off-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
40 lines
1.1 KiB
C
40 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Shared Memory Communications over RDMA (SMC-R) and RoCE
|
|
*
|
|
* Manage send buffer
|
|
*
|
|
* Copyright IBM Corp. 2016
|
|
*
|
|
* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
|
|
*/
|
|
|
|
#ifndef SMC_TX_H
|
|
#define SMC_TX_H
|
|
|
|
#include <linux/socket.h>
|
|
#include <linux/types.h>
|
|
|
|
#include "smc.h"
|
|
#include "smc_cdc.h"
|
|
|
|
static inline int smc_tx_prepared_sends(struct smc_connection *conn)
|
|
{
|
|
union smc_host_cursor sent, prep;
|
|
|
|
smc_curs_copy(&sent, &conn->tx_curs_sent, conn);
|
|
smc_curs_copy(&prep, &conn->tx_curs_prep, conn);
|
|
return smc_curs_diff(conn->sndbuf_desc->len, &sent, &prep);
|
|
}
|
|
|
|
void smc_tx_pending(struct smc_connection *conn);
|
|
void smc_tx_work(struct work_struct *work);
|
|
void smc_tx_init(struct smc_sock *smc);
|
|
int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len);
|
|
int smc_tx_sndbuf_nonempty(struct smc_connection *conn);
|
|
void smc_tx_sndbuf_nonfull(struct smc_sock *smc);
|
|
void smc_tx_consumer_update(struct smc_connection *conn, bool force);
|
|
int smcd_tx_ism_write(struct smc_connection *conn, void *data, size_t len,
|
|
u32 offset, int signal);
|
|
|
|
#endif /* SMC_TX_H */
|