From 73c900aa3660dae2050af456d1031d098ab4cb1d Mon Sep 17 00:00:00 2001 From: Gregory Detal Date: Mon, 13 May 2024 18:13:28 -0700 Subject: mptcp: add net.mptcp.available_schedulers The sysctl lists the available schedulers that can be set using net.mptcp.scheduler similarly to net.ipv4.tcp_available_congestion_control. Signed-off-by: Gregory Detal Reviewed-by: Mat Martineau Tested-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Signed-off-by: Mat Martineau Link: https://lore.kernel.org/r/20240514011335.176158-5-martineau@kernel.org Signed-off-by: Jakub Kicinski --- include/net/mptcp.h | 3 +++ net/mptcp/ctrl.c | 27 ++++++++++++++++++++++++++- net/mptcp/protocol.h | 1 + net/mptcp/sched.c | 22 ++++++++++++++++++++++ 4 files changed, 52 insertions(+), 1 deletion(-) diff --git a/include/net/mptcp.h b/include/net/mptcp.h index fb996124b3d5..0bc4ab03f487 100644 --- a/include/net/mptcp.h +++ b/include/net/mptcp.h @@ -97,6 +97,9 @@ struct mptcp_out_options { }; #define MPTCP_SCHED_NAME_MAX 16 +#define MPTCP_SCHED_MAX 128 +#define MPTCP_SCHED_BUF_MAX (MPTCP_SCHED_NAME_MAX * MPTCP_SCHED_MAX) + #define MPTCP_SUBFLOWS_MAX 8 struct mptcp_sched_data { diff --git a/net/mptcp/ctrl.c b/net/mptcp/ctrl.c index 49abf80b3fad..542555ba474c 100644 --- a/net/mptcp/ctrl.c +++ b/net/mptcp/ctrl.c @@ -133,6 +133,24 @@ static int proc_scheduler(struct ctl_table *ctl, int write, return ret; } +static int proc_available_schedulers(struct ctl_table *ctl, + int write, void *buffer, + size_t *lenp, loff_t *ppos) +{ + struct ctl_table tbl = { .maxlen = MPTCP_SCHED_BUF_MAX, }; + int ret; + + tbl.data = kmalloc(tbl.maxlen, GFP_USER); + if (!tbl.data) + return -ENOMEM; + + mptcp_get_available_schedulers(tbl.data, MPTCP_SCHED_BUF_MAX); + ret = proc_dostring(&tbl, write, buffer, lenp, ppos); + kfree(tbl.data); + + return ret; +} + static struct ctl_table mptcp_sysctl_table[] = { { .procname = "enabled", @@ -187,6 +205,12 @@ static struct ctl_table mptcp_sysctl_table[] = { .mode = 0644, .proc_handler = proc_scheduler, }, + { + .procname = "available_schedulers", + .maxlen = MPTCP_SCHED_BUF_MAX, + .mode = 0644, + .proc_handler = proc_available_schedulers, + }, { .procname = "close_timeout", .maxlen = sizeof(unsigned int), @@ -214,7 +238,8 @@ static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) table[4].data = &pernet->stale_loss_cnt; table[5].data = &pernet->pm_type; table[6].data = &pernet->scheduler; - table[7].data = &pernet->close_timeout; + /* table[7] is for available_schedulers which is read-only info */ + table[8].data = &pernet->close_timeout; hdr = register_net_sysctl_sz(net, MPTCP_SYSCTL_PATH, table, ARRAY_SIZE(mptcp_sysctl_table)); diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 4dcce3641d1d..39fc47e6b88a 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -686,6 +686,7 @@ unsigned int mptcp_stale_loss_cnt(const struct net *net); unsigned int mptcp_close_timeout(const struct sock *sk); int mptcp_get_pm_type(const struct net *net); const char *mptcp_get_scheduler(const struct net *net); +void mptcp_get_available_schedulers(char *buf, size_t maxlen); void __mptcp_subflow_fully_established(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, const struct mptcp_options_received *mp_opt); diff --git a/net/mptcp/sched.c b/net/mptcp/sched.c index 4ab0693c069c..4a7fd0508ad2 100644 --- a/net/mptcp/sched.c +++ b/net/mptcp/sched.c @@ -51,6 +51,28 @@ struct mptcp_sched_ops *mptcp_sched_find(const char *name) return ret; } +/* Build string with list of available scheduler values. + * Similar to tcp_get_available_congestion_control() + */ +void mptcp_get_available_schedulers(char *buf, size_t maxlen) +{ + struct mptcp_sched_ops *sched; + size_t offs = 0; + + rcu_read_lock(); + spin_lock(&mptcp_sched_list_lock); + list_for_each_entry_rcu(sched, &mptcp_sched_list, list) { + offs += snprintf(buf + offs, maxlen - offs, + "%s%s", + offs == 0 ? "" : " ", sched->name); + + if (WARN_ON_ONCE(offs >= maxlen)) + break; + } + spin_unlock(&mptcp_sched_list_lock); + rcu_read_unlock(); +} + int mptcp_register_scheduler(struct mptcp_sched_ops *sched) { if (!sched->get_subflow) -- cgit v1.2.3