diff mbox series

[net,v3,2/2] net/smc: fix unexpected SMC_CLC_DECL_ERR_REGRMB error cause by server

Message ID a495b3c6d6cb8002a7a0e73da9b83720b9819e3a.1646227183.git.alibuda@linux.alibaba.com (mailing list archive)
State Not Applicable
Headers show
Series fix unexpected SMC_CLC_DECL_ERR_REGRMB error | expand

Commit Message

D. Wythe March 2, 2022, 1:25 p.m. UTC 
From: "D. Wythe" <alibuda@linux.alibaba.com>

The problem of SMC_CLC_DECL_ERR_REGRMB on the server is very clear.
Based on the fact that whether a new SMC connection can be accepted or
not depends on not only the limit of conn nums, but also the available
entries of rtoken. Since the rtoken release is trigger by peer, while
the conn nums is decrease by local, tons of thing can happen in this
time difference.

This only thing that needs to be mentioned is that now all connection
creations are completely protected by smc_server_lgr_pending lock, it's
enough to check only the available entries in rtokens_used_mask.

Fixes: cd6851f30386 ("smc: remote memory buffers (RMBs)")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
---
 net/smc/smc_core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index f8c9675..be7d704 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -1864,7 +1864,8 @@  int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
 		    (ini->smcd_version == SMC_V2 ||
 		     lgr->vlan_id == ini->vlan_id) &&
 		    (role == SMC_CLNT || ini->is_smcd ||
-		     lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) {
+		    (lgr->conns_num < SMC_RMBS_PER_LGR_MAX &&
+		      !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
 			/* link group found */
 			ini->first_contact_local = 0;
 			conn->lgr = lgr;