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>
This commit is contained in:
Guvenc Gulce 2021-06-16 16:52:57 +02:00 committed by David S. Miller
parent 8c40602b4b
commit f0dd7bf5e3
5 changed files with 113 additions and 1 deletions

View File

@ -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 */

View File

@ -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] = {

View File

@ -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)

View File

@ -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;
}

View File

@ -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);