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 <guvenc@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/smc/smc_stats.c b/net/smc/smc_stats.c
index 72119d3..b3d279d 100644
--- a/net/smc/smc_stats.c
+++ b/net/smc/smc_stats.c
@@ -312,3 +312,95 @@ int smc_nl_get_stats(struct sk_buff *skb,
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;
+}