Skip to content

Commit

Permalink
net/smc: asymmetric link tagging
Browse files Browse the repository at this point in the history 
New connections must not be assigned to asymmetric links. Add asymmetric
link tagging using new link variable link_is_asym. The new helpers
smcr_lgr_set_type() and smcr_lgr_set_type_asym() are called to set the
state of the link group, and tag all links accordingly.
smcr_lgr_conn_assign_link() respects the link tagging and will not
assign new connections to links tagged as asymmetric link.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Karsten Graul authored and David S. Miller committed May 4, 2020
1 parent 56bc3b2 commit ad6c111
Show file tree
Hide file tree
Showing 3 changed files with 41 additions and 9 deletions.
26 changes: 23 additions & 3 deletions net/smc/smc_core.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -132,7 +132,7 @@ static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
struct smc_link *lnk = &conn->lgr->lnk[i];

if (lnk->state != expected)
if (lnk->state != expected || lnk->link_is_asym)
continue;
if (conn->lgr->role == SMC_CLNT) {
conn->lnk = lnk; /* temporary, SMC server assigns link*/
Expand All @@ -143,7 +143,8 @@ static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
struct smc_link *lnk2;

lnk2 = &conn->lgr->lnk[j];
if (lnk2->state == expected) {
if (lnk2->state == expected &&
!lnk2->link_is_asym) {
conn->lnk = lnk2;
break;
}
Expand Down Expand Up @@ -1030,6 +1031,25 @@ void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
}
}

/* set new lgr type and clear all asymmetric link tagging */
void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
{
int i;

for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
if (smc_link_usable(&lgr->lnk[i]))
lgr->lnk[i].link_is_asym = false;
lgr->type = new_type;
}

/* set new lgr type and tag a link as asymmetric */
void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
enum smc_lgr_type new_type, int asym_lnk_idx)
{
smcr_lgr_set_type(lgr, new_type);
lgr->lnk[asym_lnk_idx].link_is_asym = true;
}

/* abort connection, abort_work scheduled from tasklet context */
static void smc_conn_abort_work(struct work_struct *work)
{
Expand Down Expand Up @@ -1123,7 +1143,7 @@ static void smcr_link_down(struct smc_link *lnk)
smcr_link_clear(lnk);
return;
}
lgr->type = SMC_LGR_SINGLE;
smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
del_link_id = lnk->link_id;

if (lgr->role == SMC_SERV) {
Expand Down
4 changes: 4 additions & 0 deletions net/smc/smc_core.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -117,6 +117,7 @@ struct smc_link {
u8 peer_gid[SMC_GID_SIZE]; /* gid of peer*/
u8 link_id; /* unique # within link group */
u8 link_idx; /* index in lgr link array */
u8 link_is_asym; /* is link asymmetric? */
struct smc_link_group *lgr; /* parent link group */
struct work_struct link_down_wrk; /* wrk to bring link down */

Expand Down Expand Up @@ -380,6 +381,9 @@ int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
void smcr_link_clear(struct smc_link *lnk);
int smcr_buf_map_lgr(struct smc_link *lnk);
int smcr_buf_reg_lgr(struct smc_link *lnk);
void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type);
void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
enum smc_lgr_type new_type, int asym_lnk_idx);
int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc);
struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
struct smc_link *from_lnk, bool is_dev_err);
Expand Down
20 changes: 14 additions & 6 deletions net/smc/smc_llc.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -796,7 +796,11 @@ static int smc_llc_cli_conf_link(struct smc_link *link,
return -ENOLINK;
}
smc_llc_link_active(link_new);
lgr->type = lgr_new_t;
if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)
smcr_lgr_set_type_asym(lgr, lgr_new_t, link_new->link_idx);
else
smcr_lgr_set_type(lgr, lgr_new_t);
return 0;
}

Expand Down Expand Up @@ -1038,7 +1042,11 @@ static int smc_llc_srv_conf_link(struct smc_link *link,
return -ENOLINK;
}
smc_llc_link_active(link_new);
lgr->type = lgr_new_t;
if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)
smcr_lgr_set_type_asym(lgr, lgr_new_t, link_new->link_idx);
else
smcr_lgr_set_type(lgr, lgr_new_t);
smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
return 0;
}
Expand Down Expand Up @@ -1223,9 +1231,9 @@ static void smc_llc_process_cli_delete_link(struct smc_link_group *lgr)
if (lnk_del == lnk_asym) {
/* expected deletion of asym link, don't change lgr state */
} else if (active_links == 1) {
lgr->type = SMC_LGR_SINGLE;
smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
} else if (!active_links) {
lgr->type = SMC_LGR_NONE;
smcr_lgr_set_type(lgr, SMC_LGR_NONE);
smc_lgr_terminate_sched(lgr);
}
out_unlock:
Expand Down Expand Up @@ -1314,9 +1322,9 @@ static void smc_llc_process_srv_delete_link(struct smc_link_group *lgr)

active_links = smc_llc_active_link_count(lgr);
if (active_links == 1) {
lgr->type = SMC_LGR_SINGLE;
smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
} else if (!active_links) {
lgr->type = SMC_LGR_NONE;
smcr_lgr_set_type(lgr, SMC_LGR_NONE);
smc_lgr_terminate_sched(lgr);
}

Expand Down

0 comments on commit ad6c111

Please sign in to comment.