From f0dd7bf5e33066e554442c509ef6351728b95b51 Mon Sep 17 00:00:00 2001 From: Guvenc Gulce Date: Wed, 16 Jun 2021 16:52:57 +0200 Subject: [PATCH] net/smc: Add netlink support for SMC fallback statistics Add support to collect more detailed SMC fallback reason statistics and provide these statistics to user space on the netlink interface. Signed-off-by: Guvenc Gulce Signed-off-by: Karsten Graul Signed-off-by: David S. Miller --- include/uapi/linux/smc.h | 14 ++++++++ net/smc/smc_netlink.c | 5 +++ net/smc/smc_netlink.h | 2 +- net/smc/smc_stats.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++ net/smc/smc_stats.h | 1 + 5 files changed, 113 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/smc.h b/include/uapi/linux/smc.h index f32f11b30963..0f7f87c70baf 100644 --- a/include/uapi/linux/smc.h +++ b/include/uapi/linux/smc.h @@ -48,6 +48,7 @@ enum { SMC_NETLINK_GET_DEV_SMCD, SMC_NETLINK_GET_DEV_SMCR, SMC_NETLINK_GET_STATS, + SMC_NETLINK_GET_FBACK_STATS, }; /* SMC_GENL_FAMILY top level attributes */ @@ -60,6 +61,7 @@ enum { SMC_GEN_DEV_SMCD, /* nest */ SMC_GEN_DEV_SMCR, /* nest */ SMC_GEN_STATS, /* nest */ + SMC_GEN_FBACK_STATS, /* nest */ __SMC_GEN_MAX, SMC_GEN_MAX = __SMC_GEN_MAX - 1 }; @@ -228,4 +230,16 @@ enum { __SMC_NLA_STATS_MAX, SMC_NLA_STATS_MAX = __SMC_NLA_STATS_MAX - 1 }; + +/* SMC_GEN_FBACK_STATS attributes */ +enum { + SMC_NLA_FBACK_STATS_PAD, + SMC_NLA_FBACK_STATS_TYPE, /* u8 */ + SMC_NLA_FBACK_STATS_SRV_CNT, /* u64 */ + SMC_NLA_FBACK_STATS_CLNT_CNT, /* u64 */ + SMC_NLA_FBACK_STATS_RSN_CODE, /* u32 */ + SMC_NLA_FBACK_STATS_RSN_CNT, /* u16 */ + __SMC_NLA_FBACK_STATS_MAX, + SMC_NLA_FBACK_STATS_MAX = __SMC_NLA_FBACK_STATS_MAX - 1 +}; #endif /* _UAPI_LINUX_SMC_H */ diff --git a/net/smc/smc_netlink.c b/net/smc/smc_netlink.c index 30e30b23370f..6fb6f96c1d17 100644 --- a/net/smc/smc_netlink.c +++ b/net/smc/smc_netlink.c @@ -61,6 +61,11 @@ static const struct genl_ops smc_gen_nl_ops[] = { /* can be retrieved by unprivileged users */ .dumpit = smc_nl_get_stats, }, + { + .cmd = SMC_NETLINK_GET_FBACK_STATS, + /* can be retrieved by unprivileged users */ + .dumpit = smc_nl_get_fback_stats, + }, }; static const struct nla_policy smc_gen_nl_policy[2] = { diff --git a/net/smc/smc_netlink.h b/net/smc/smc_netlink.h index 3477265cba6c..5ce2c0a89ccd 100644 --- a/net/smc/smc_netlink.h +++ b/net/smc/smc_netlink.h @@ -18,7 +18,7 @@ extern struct genl_family smc_gen_nl_family; struct smc_nl_dmp_ctx { - int pos[2]; + int pos[3]; }; static inline struct smc_nl_dmp_ctx *smc_nl_dmp_ctx(struct netlink_callback *c) diff --git a/net/smc/smc_stats.c b/net/smc/smc_stats.c index 72119d3d8558..b3d279d29c52 100644 --- a/net/smc/smc_stats.c +++ b/net/smc/smc_stats.c @@ -312,3 +312,95 @@ errnest: errmsg: return skb->len; } + +static int smc_nl_get_fback_details(struct sk_buff *skb, + struct netlink_callback *cb, int pos, + bool is_srv) +{ + struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); + int cnt_reported = cb_ctx->pos[2]; + struct smc_stats_fback *trgt_arr; + struct nlattr *attrs; + int rc = 0; + void *nlh; + + if (is_srv) + trgt_arr = &fback_rsn.srv[0]; + else + trgt_arr = &fback_rsn.clnt[0]; + if (!trgt_arr[pos].fback_code) + return -ENODATA; + nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &smc_gen_nl_family, NLM_F_MULTI, + SMC_NETLINK_GET_FBACK_STATS); + if (!nlh) + goto errmsg; + attrs = nla_nest_start(skb, SMC_GEN_FBACK_STATS); + if (!attrs) + goto errout; + if (nla_put_u8(skb, SMC_NLA_FBACK_STATS_TYPE, is_srv)) + goto errattr; + if (!cnt_reported) { + if (nla_put_u64_64bit(skb, SMC_NLA_FBACK_STATS_SRV_CNT, + fback_rsn.srv_fback_cnt, + SMC_NLA_FBACK_STATS_PAD)) + goto errattr; + if (nla_put_u64_64bit(skb, SMC_NLA_FBACK_STATS_CLNT_CNT, + fback_rsn.clnt_fback_cnt, + SMC_NLA_FBACK_STATS_PAD)) + goto errattr; + cnt_reported = 1; + } + + if (nla_put_u32(skb, SMC_NLA_FBACK_STATS_RSN_CODE, + trgt_arr[pos].fback_code)) + goto errattr; + if (nla_put_u16(skb, SMC_NLA_FBACK_STATS_RSN_CNT, + trgt_arr[pos].count)) + goto errattr; + + cb_ctx->pos[2] = cnt_reported; + nla_nest_end(skb, attrs); + genlmsg_end(skb, nlh); + return rc; + +errattr: + nla_nest_cancel(skb, attrs); +errout: + genlmsg_cancel(skb, nlh); +errmsg: + return -EMSGSIZE; +} + +int smc_nl_get_fback_stats(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); + int rc_srv = 0, rc_clnt = 0, k; + int skip_serv = cb_ctx->pos[1]; + int snum = cb_ctx->pos[0]; + bool is_srv = true; + + mutex_lock(&smc_stat_fback_rsn); + for (k = 0; k < SMC_MAX_FBACK_RSN_CNT; k++) { + if (k < snum) + continue; + if (!skip_serv) { + rc_srv = smc_nl_get_fback_details(skb, cb, k, is_srv); + if (rc_srv && rc_srv != ENODATA) + break; + } else { + skip_serv = 0; + } + rc_clnt = smc_nl_get_fback_details(skb, cb, k, !is_srv); + if (rc_clnt && rc_clnt != ENODATA) { + skip_serv = 1; + break; + } + if (rc_clnt == ENODATA && rc_srv == ENODATA) + break; + } + mutex_unlock(&smc_stat_fback_rsn); + cb_ctx->pos[1] = skip_serv; + cb_ctx->pos[0] = k; + return skb->len; +} diff --git a/net/smc/smc_stats.h b/net/smc/smc_stats.h index 84baaca59eaf..7c35b22d9e29 100644 --- a/net/smc/smc_stats.h +++ b/net/smc/smc_stats.h @@ -248,6 +248,7 @@ do { \ while (0) int smc_nl_get_stats(struct sk_buff *skb, struct netlink_callback *cb); +int smc_nl_get_fback_stats(struct sk_buff *skb, struct netlink_callback *cb); int smc_stats_init(void) __init; void smc_stats_exit(void); -- 2.11.0