From: Wen Gu Date: Sun, 28 Apr 2024 06:07:29 +0000 (+0800) Subject: net/smc: introduce loopback-ism for SMC intra-OS shortcut X-Git-Tag: net-accept-more-20240515~4^2~93^2~9 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=46ac64419ded7bcbe1fb8d0f4df3258384a425c2;hp=784c46f5467c3cd516e518de211e26611da5c0fb;p=linux-2.6-block.git net/smc: introduce loopback-ism for SMC intra-OS shortcut This introduces a kind of Emulated-ISM device named loopback-ism for SMCv2.1. The loopback-ism device is currently exclusive for SMC usage, and aims to provide an SMC shortcut for sockets within the same kernel, leading to improved intra-OS traffic performance. Configuration of this feature is managed through the config SMC_LO. Signed-off-by: Wen Gu Reviewed-by: Gerd Bayer Reviewed-by: Wenjia Zhang Reviewed-and-tested-by: Jan Karcher Signed-off-by: Paolo Abeni --- diff --git a/net/smc/Kconfig b/net/smc/Kconfig index 746be3996768..ba5e6a2dd2fd 100644 --- a/net/smc/Kconfig +++ b/net/smc/Kconfig @@ -20,3 +20,16 @@ config SMC_DIAG smcss. if unsure, say Y. + +config SMC_LO + bool "SMC intra-OS shortcut with loopback-ism" + depends on SMC + default n + help + SMC_LO enables the creation of an Emulated-ISM device named + loopback-ism in SMC and makes use of it for transferring data + when communication occurs within the same OS. This helps in + convenient testing of SMC-D since loopback-ism is independent + of architecture or hardware. + + if unsure, say N. diff --git a/net/smc/Makefile b/net/smc/Makefile index 875efcd126a2..2c510d543058 100644 --- a/net/smc/Makefile +++ b/net/smc/Makefile @@ -6,3 +6,4 @@ smc-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o smc_core.o smc_wr.o smc_llc.o smc-y += smc_cdc.o smc_tx.o smc_rx.o smc_close.o smc_ism.o smc_netlink.o smc_stats.o smc-y += smc_tracepoint.o smc-$(CONFIG_SYSCTL) += smc_sysctl.o +smc-$(CONFIG_SMC_LO) += smc_loopback.o diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index e8dcd28a554c..47f3bc1470bc 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -53,6 +53,7 @@ #include "smc_stats.h" #include "smc_tracepoint.h" #include "smc_sysctl.h" +#include "smc_loopback.h" static DEFINE_MUTEX(smc_server_lgr_pending); /* serialize link group * creation on server @@ -3555,15 +3556,23 @@ static int __init smc_init(void) goto out_sock; } + rc = smc_loopback_init(); + if (rc) { + pr_err("%s: smc_loopback_init fails with %d\n", __func__, rc); + goto out_ib; + } + rc = tcp_register_ulp(&smc_ulp_ops); if (rc) { pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc); - goto out_ib; + goto out_lo; } static_branch_enable(&tcp_have_smc); return 0; +out_lo: + smc_loopback_exit(); out_ib: smc_ib_unregister_client(); out_sock: @@ -3601,6 +3610,7 @@ static void __exit smc_exit(void) tcp_unregister_ulp(&smc_ulp_ops); sock_unregister(PF_SMC); smc_core_exit(); + smc_loopback_exit(); smc_ib_unregister_client(); smc_ism_exit(); destroy_workqueue(smc_close_wq); diff --git a/net/smc/smc_loopback.c b/net/smc/smc_loopback.c new file mode 100644 index 000000000000..c364e3e6e3fb --- /dev/null +++ b/net/smc/smc_loopback.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Shared Memory Communications Direct over loopback-ism device. + * + * Functions for loopback-ism device. + * + * Copyright (c) 2024, Alibaba Inc. + * + * Author: Wen Gu + * Tony Lu + * + */ + +#include +#include +#include + +#include "smc_ism.h" +#include "smc_loopback.h" + +static const char smc_lo_dev_name[] = "loopback-ism"; +static struct smc_lo_dev *lo_dev; + +static const struct smcd_ops lo_ops = { + .query_remote_gid = NULL, + .register_dmb = NULL, + .unregister_dmb = NULL, + .add_vlan_id = NULL, + .del_vlan_id = NULL, + .set_vlan_required = NULL, + .reset_vlan_required = NULL, + .signal_event = NULL, + .move_data = NULL, + .supports_v2 = NULL, + .get_local_gid = NULL, + .get_chid = NULL, + .get_dev = NULL, +}; + +static struct smcd_dev *smcd_lo_alloc_dev(const struct smcd_ops *ops, + int max_dmbs) +{ + struct smcd_dev *smcd; + + smcd = kzalloc(sizeof(*smcd), GFP_KERNEL); + if (!smcd) + return NULL; + + smcd->conn = kcalloc(max_dmbs, sizeof(struct smc_connection *), + GFP_KERNEL); + if (!smcd->conn) + goto out_smcd; + + smcd->ops = ops; + + spin_lock_init(&smcd->lock); + spin_lock_init(&smcd->lgr_lock); + INIT_LIST_HEAD(&smcd->vlan); + INIT_LIST_HEAD(&smcd->lgr_list); + init_waitqueue_head(&smcd->lgrs_deleted); + return smcd; + +out_smcd: + kfree(smcd); + return NULL; +} + +static int smcd_lo_register_dev(struct smc_lo_dev *ldev) +{ + struct smcd_dev *smcd; + + smcd = smcd_lo_alloc_dev(&lo_ops, SMC_LO_MAX_DMBS); + if (!smcd) + return -ENOMEM; + ldev->smcd = smcd; + smcd->priv = ldev; + + /* TODO: + * register loopback-ism to smcd_dev list. + */ + return 0; +} + +static void smcd_lo_unregister_dev(struct smc_lo_dev *ldev) +{ + struct smcd_dev *smcd = ldev->smcd; + + /* TODO: + * unregister loopback-ism from smcd_dev list. + */ + kfree(smcd->conn); + kfree(smcd); +} + +static int smc_lo_dev_init(struct smc_lo_dev *ldev) +{ + return smcd_lo_register_dev(ldev); +} + +static void smc_lo_dev_exit(struct smc_lo_dev *ldev) +{ + smcd_lo_unregister_dev(ldev); +} + +static void smc_lo_dev_release(struct device *dev) +{ + struct smc_lo_dev *ldev = + container_of(dev, struct smc_lo_dev, dev); + + kfree(ldev); +} + +static int smc_lo_dev_probe(void) +{ + struct smc_lo_dev *ldev; + int ret; + + ldev = kzalloc(sizeof(*ldev), GFP_KERNEL); + if (!ldev) + return -ENOMEM; + + ldev->dev.parent = NULL; + ldev->dev.release = smc_lo_dev_release; + device_initialize(&ldev->dev); + dev_set_name(&ldev->dev, smc_lo_dev_name); + + ret = smc_lo_dev_init(ldev); + if (ret) + goto free_dev; + + lo_dev = ldev; /* global loopback device */ + return 0; + +free_dev: + put_device(&ldev->dev); + return ret; +} + +static void smc_lo_dev_remove(void) +{ + if (!lo_dev) + return; + + smc_lo_dev_exit(lo_dev); + put_device(&lo_dev->dev); /* device_initialize in smc_lo_dev_probe */ +} + +int smc_loopback_init(void) +{ + return smc_lo_dev_probe(); +} + +void smc_loopback_exit(void) +{ + smc_lo_dev_remove(); +} diff --git a/net/smc/smc_loopback.h b/net/smc/smc_loopback.h new file mode 100644 index 000000000000..7fc4b374bc82 --- /dev/null +++ b/net/smc/smc_loopback.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Shared Memory Communications Direct over loopback-ism device. + * + * SMC-D loopback-ism device structure definitions. + * + * Copyright (c) 2024, Alibaba Inc. + * + * Author: Wen Gu + * Tony Lu + * + */ + +#ifndef _SMC_LOOPBACK_H +#define _SMC_LOOPBACK_H + +#include +#include +#include + +#if IS_ENABLED(CONFIG_SMC_LO) +#define SMC_LO_MAX_DMBS 5000 + +struct smc_lo_dev { + struct smcd_dev *smcd; + struct device dev; +}; + +int smc_loopback_init(void); +void smc_loopback_exit(void); +#else +static inline int smc_loopback_init(void) +{ + return 0; +} + +static inline void smc_loopback_exit(void) +{ +} +#endif + +#endif /* _SMC_LOOPBACK_H */