Commit 30b53668 authored by Guvenc Gulce's avatar Guvenc Gulce Committed by Litao Jiao
Browse files

net/smc: Add netlink support for SMC fallback statistics 

mainline inclusion
from mainline-v5.14-rc1
commit f0dd7bf5
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I78IFM
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=f0dd7bf5e33066e554442c509ef6351728b95b51



--------------------------------

Add support to collect more detailed SMC fallback reason statistics and
provide these statistics to user space on the netlink interface.

Signed-off-by: default avatarGuvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: default avatarKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarYingyu Zeng <zengyingyu@sangfor.com.cn>
parent 0ead8062

include/uapi/linux/smc.h

+14 −0
Original line number Diff line number Diff line
@@ -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 */

net/smc/smc_netlink.c

+5 −0
Original line number Diff line number Diff line
@@ -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] = {

net/smc/smc_netlink.h

+1 −1
Original line number Diff line number Diff line
@@ -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)

net/smc/smc_stats.c

+92 −0
Original line number Diff line number Diff line
@@ -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;

}

net/smc/smc_stats.h

+1 −0
Original line number Diff line number Diff line
@@ -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);