From: Ursula Braun <ubraun@xxxxxxxxxxxxx>
Usually link groups are freed delayed to enable quick connection
creation for a follow-on SMC socket. Terminated link groups are
freed faster. This patch makes sure, fast schedule of link group
freeing is not rescheduled by a delayed schedule. And it makes sure
link group freeing is not rescheduled, if the real freeing is already
running.
Signed-off-by: Ursula Braun <ubraun@xxxxxxxxxxxxx>
Signed-off-by: Karsten Graul <kgraul@xxxxxxxxxxxxx>
---
net/smc/smc_core.c | 47 +++++++++++++++++++++++++++++-----------------
net/smc/smc_core.h | 2 ++
2 files changed, 32 insertions(+), 17 deletions(-)
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 1f58cd82928c..e7e9dbcd7d8b 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -61,14 +61,21 @@ static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
* creation. For client use a somewhat higher removal delay time,
* otherwise there is a risk of out-of-sync link groups.
*/
- mod_delayed_work(system_wq, &lgr->free_work,
- (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
- SMC_LGR_FREE_DELAY_CLNT : SMC_LGR_FREE_DELAY_SERV);
+ if (!lgr->freeing && !lgr->freefast) {
+ mod_delayed_work(system_wq, &lgr->free_work,
+ (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
+ SMC_LGR_FREE_DELAY_CLNT :
+ SMC_LGR_FREE_DELAY_SERV);
+ }
}
void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr)
{
- mod_delayed_work(system_wq, &lgr->free_work, SMC_LGR_FREE_DELAY_FAST);
+ if (!lgr->freeing && !lgr->freefast) {
+ lgr->freefast = 1;
+ mod_delayed_work(system_wq, &lgr->free_work,
+ SMC_LGR_FREE_DELAY_FAST);
+ }
}
/* Register connection's alert token in our lookup structure.
@@ -171,10 +178,15 @@ static void smc_lgr_free_work(struct work_struct *work)
struct smc_link_group,
free_work);
spinlock_t *lgr_lock;
+ struct smc_link *lnk;
bool conns;
smc_lgr_list_head(lgr, &lgr_lock);
spin_lock_bh(lgr_lock);
+ if (lgr->freeing) {
+ spin_unlock_bh(lgr_lock);
+ return;
+ }
read_lock_bh(&lgr->conns_lock);
conns = RB_EMPTY_ROOT(&lgr->conns_all);
read_unlock_bh(&lgr->conns_lock);
@@ -183,29 +195,27 @@ static void smc_lgr_free_work(struct work_struct *work)
return;
}
list_del_init(&lgr->list); /* remove from smc_lgr_list */
- spin_unlock_bh(lgr_lock);
+ lnk = &lgr->lnk[SMC_SINGLE_LINK];
if (!lgr->is_smcd && !lgr->terminating) {
- struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
-
/* try to send del link msg, on error free lgr immediately */
if (lnk->state == SMC_LNK_ACTIVE &&
!smc_link_send_delete(lnk)) {
/* reschedule in case we never receive a response */
smc_lgr_schedule_free_work(lgr);
+ spin_unlock_bh(lgr_lock);
return;
}
}
+ lgr->freeing = 1; /* this instance does the freeing, no new schedule */
+ spin_unlock_bh(lgr_lock);
+ cancel_delayed_work(&lgr->free_work);
- if (!delayed_work_pending(&lgr->free_work)) {
- struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
-
- if (!lgr->is_smcd && lnk->state != SMC_LNK_INACTIVE)
- smc_llc_link_inactive(lnk);
- if (lgr->is_smcd)
- smc_ism_signal_shutdown(lgr);
- smc_lgr_free(lgr);
- }
+ if (!lgr->is_smcd && lnk->state != SMC_LNK_INACTIVE)
+ smc_llc_link_inactive(lnk);
+ if (lgr->is_smcd)
+ smc_ism_signal_shutdown(lgr);
+ smc_lgr_free(lgr);
}
/* create a new SMC link group */
@@ -233,6 +243,9 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
}
lgr->is_smcd = ini->is_smcd;
lgr->sync_err = 0;
+ lgr->terminating = 0;
+ lgr->freefast = 0;
+ lgr->freeing = 0;
lgr->vlan_id = ini->vlan_id;
rwlock_init(&lgr->sndbufs_lock);
rwlock_init(&lgr->rmbs_lock);
@@ -513,7 +526,7 @@ static void __smc_lgr_terminate(struct smc_link_group *lgr)
read_unlock_bh(&lgr->conns_lock);
if (!lgr->is_smcd)
wake_up(&lgr->lnk[SMC_SINGLE_LINK].wr_reg_wait);
- smc_lgr_schedule_free_work(lgr);
+ smc_lgr_schedule_free_work_fast(lgr);
}
/* unlink and terminate link group */
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index c00ac61dc129..12c2818b293f 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -204,6 +204,8 @@ struct smc_link_group {
struct delayed_work free_work; /* delayed freeing of an lgr */
u8 sync_err : 1; /* lgr no longer fits to peer */
u8 terminating : 1;/* lgr is terminating */
+ u8 freefast : 1; /* free worker scheduled fast */
+ u8 freeing : 1; /* lgr is being freed */
bool is_smcd; /* SMC-R or SMC-D */
union {
--
2.17.1
