[PATCH net-next v2 06/15] net/smc: Add diagnostic information to link structure

Karsten Graul
2020-11-03T10:25:54Z

During link creation add network and ib-device name to
link structure. This is needed for diagnostic purposes.

When diagnostic information is gathered, we need to traverse
device, linkgroup and link structures, to be able to do that
we need to hold a spinlock for the linkgroup list, without this
diagnostic information in link structure, another device list
mutex holding would be necessary to dereference the device
pointer in the link structure which would be impossible when
holding a spinlock already.

Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
---
net/smc/smc_core.c | 10 ++++++++++
net/smc/smc_core.h | 3 +++
2 files changed, 13 insertions(+)

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index da94725deb09..28fc583d9033 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -303,6 +303,15 @@ static u8 smcr_next_link_id(struct smc_link_group *lgr)
return link_id;
}

+static inline void smcr_copy_dev_info_to_link(struct smc_link *link)
+{
+ struct smc_ib_device *smcibdev = link->smcibdev;
+
+ memcpy(link->ibname, smcibdev->ibdev->name, sizeof(link->ibname));
+ memcpy(link->ndevname, smcibdev->netdev[link->ibport - 1],
+ sizeof(link->ndevname));
+}
+
int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
u8 link_idx, struct smc_init_info *ini)
{
@@ -317,6 +326,7 @@ int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
lnk->smcibdev = ini->ib_dev;
lnk->ibport = ini->ib_port;
atomic_inc(&ini->ib_dev->lnk_cnt_by_port[ini->ib_port - 1]);
+ smcr_copy_dev_info_to_link(lnk);
lnk->path_mtu = ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;
atomic_set(&lnk->conn_cnt, 0);
smc_llc_link_set_uid(lnk);
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 83a88a4635db..bd16d63c5222 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -124,6 +124,9 @@ struct smc_link {
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 */
+ /* Diagnostic relevant link information */
+ u8 ibname[IB_DEVICE_NAME_MAX];/* ib device name */
+ u8 ndevname[IFNAMSIZ];/* network device name */

enum smc_link_state state; /* state of link */
struct delayed_work llc_testlink_wrk; /* testlink worker */
--
2.17.1