Commit a0a62ee1 authored by Ursula Braun's avatar Ursula Braun Committed by Jakub Kicinski
Browse files

net/smc: separate locks for SMCD and SMCR link group lists 



This patch introduces separate locks for the split SMCD and SMCR
link group lists.

Signed-off-by: default avatarUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: default avatarKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
parent a2351c5d

include/net/smc.h

+1 −0
Original line number Diff line number Diff line
@@ -76,6 +76,7 @@ struct smcd_dev { 
	u8 pnetid[SMC_MAX_PNETID_LEN];

	bool pnetid_by_user;

	struct list_head lgr_list;

	spinlock_t lgr_lock;

};



struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,

net/smc/smc_core.c

+42 −15
Original line number Diff line number Diff line
@@ -42,6 +42,19 @@ static struct smc_lgr_list smc_lgr_list = { /* established link groups */ 
static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,

			 struct smc_buf_desc *buf_desc);



/* return head of link group list and its lock for a given link group */

static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,

						  spinlock_t **lgr_lock)

{

	if (lgr->is_smcd) {

		*lgr_lock = &lgr->smcd->lgr_lock;

		return &lgr->smcd->lgr_list;

	}



	*lgr_lock = &smc_lgr_list.lock;

	return &smc_lgr_list.list;

}



static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)

{

	/* client link group creation always follows the server link group
@@ -157,19 +170,21 @@ static void smc_lgr_free_work(struct work_struct *work) 
	struct smc_link_group *lgr = container_of(to_delayed_work(work),

						  struct smc_link_group,

						  free_work);

	spinlock_t *lgr_lock;

	bool conns;



	spin_lock_bh(&smc_lgr_list.lock);

	smc_lgr_list_head(lgr, &lgr_lock);

	spin_lock_bh(lgr_lock);

	read_lock_bh(&lgr->conns_lock);

	conns = RB_EMPTY_ROOT(&lgr->conns_all);

	read_unlock_bh(&lgr->conns_lock);

	if (!conns) { /* number of lgr connections is no longer zero */

		spin_unlock_bh(&smc_lgr_list.lock);

		spin_unlock_bh(lgr_lock);

		return;

	}

	if (!list_empty(&lgr->list))

		list_del_init(&lgr->list); /* remove from smc_lgr_list */

	spin_unlock_bh(&smc_lgr_list.lock);

	spin_unlock_bh(lgr_lock);



	if (!lgr->is_smcd && !lgr->terminating)	{

		struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
@@ -200,6 +215,7 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) 
	struct smc_link_group *lgr;

	struct list_head *lgr_list;

	struct smc_link *lnk;

	spinlock_t *lgr_lock;

	u8 rndvec[3];

	int rc = 0;

	int i;
@@ -235,6 +251,7 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) 
		lgr->peer_gid = ini->ism_gid;

		lgr->smcd = ini->ism_dev;

		lgr_list = &ini->ism_dev->lgr_list;

		lgr_lock = &lgr->smcd->lgr_lock;

	} else {

		/* SMC-R specific settings */

		lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
@@ -248,6 +265,7 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) 
		lnk->smcibdev = ini->ib_dev;

		lnk->ibport = ini->ib_port;

		lgr_list = &smc_lgr_list.list;

		lgr_lock = &smc_lgr_list.lock;

		lnk->path_mtu =

			ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;

		if (!ini->ib_dev->initialized)
@@ -277,9 +295,9 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini) 
			goto destroy_qp;

	}

	smc->conn.lgr = lgr;

	spin_lock_bh(&smc_lgr_list.lock);

	spin_lock_bh(lgr_lock);

	list_add(&lgr->list, lgr_list);

	spin_unlock_bh(&smc_lgr_list.lock);

	spin_unlock_bh(lgr_lock);

	return 0;



destroy_qp:
@@ -442,11 +460,15 @@ static void smc_lgr_free(struct smc_link_group *lgr) 


void smc_lgr_forget(struct smc_link_group *lgr)

{

	spin_lock_bh(&smc_lgr_list.lock);

	struct list_head *lgr_list;

	spinlock_t *lgr_lock;



	lgr_list = smc_lgr_list_head(lgr, &lgr_lock);

	spin_lock_bh(lgr_lock);

	/* do not use this link group for new connections */

	if (!list_empty(&lgr->list))

		list_del_init(&lgr->list);

	spin_unlock_bh(&smc_lgr_list.lock);

	if (!list_empty(lgr_list))

		list_del_init(lgr_list);

	spin_unlock_bh(lgr_lock);

}



/* terminate linkgroup abnormally */
@@ -487,9 +509,12 @@ static void __smc_lgr_terminate(struct smc_link_group *lgr) 


void smc_lgr_terminate(struct smc_link_group *lgr)

{

	spin_lock_bh(&smc_lgr_list.lock);

	spinlock_t *lgr_lock;



	smc_lgr_list_head(lgr, &lgr_lock);

	spin_lock_bh(lgr_lock);

	__smc_lgr_terminate(lgr);

	spin_unlock_bh(&smc_lgr_list.lock);

	spin_unlock_bh(lgr_lock);

}



/* Called when IB port is terminated */
@@ -514,7 +539,7 @@ void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan) 
	LIST_HEAD(lgr_free_list);



	/* run common cleanup function and build free list */

	spin_lock_bh(&smc_lgr_list.lock);

	spin_lock_bh(&dev->lgr_lock);

	list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {

		if ((!peer_gid || lgr->peer_gid == peer_gid) &&

		    (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
@@ -522,7 +547,7 @@ void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan) 
			list_move(&lgr->list, &lgr_free_list);

		}

	}

	spin_unlock_bh(&smc_lgr_list.lock);

	spin_unlock_bh(&dev->lgr_lock);



	/* cancel the regular free workers and actually free lgrs */

	list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
@@ -609,9 +634,11 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) 
	struct list_head *lgr_list;

	struct smc_link_group *lgr;

	enum smc_lgr_role role;

	spinlock_t *lgr_lock;

	int rc = 0;



	lgr_list = ini->is_smcd ? &ini->ism_dev->lgr_list : &smc_lgr_list.list;

	lgr_lock = ini->is_smcd ? &ini->ism_dev->lgr_lock : &smc_lgr_list.lock;

	ini->cln_first_contact = SMC_FIRST_CONTACT;

	role = smc->listen_smc ? SMC_SERV : SMC_CLNT;

	if (role == SMC_CLNT && ini->srv_first_contact)
@@ -619,7 +646,7 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) 
		goto create;



	/* determine if an existing link group can be reused */

	spin_lock_bh(&smc_lgr_list.lock);

	spin_lock_bh(lgr_lock);

	list_for_each_entry(lgr, lgr_list, list) {

		write_lock_bh(&lgr->conns_lock);

		if ((ini->is_smcd ?
@@ -640,7 +667,7 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) 
		}

		write_unlock_bh(&lgr->conns_lock);

	}

	spin_unlock_bh(&smc_lgr_list.lock);

	spin_unlock_bh(lgr_lock);



	if (role == SMC_CLNT && !ini->srv_first_contact &&

	    ini->cln_first_contact == SMC_FIRST_CONTACT) {

net/smc/smc_ism.c

+1 −0
Original line number Diff line number Diff line
@@ -286,6 +286,7 @@ struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name, 
	smc_pnetid_by_dev_port(parent, 0, smcd->pnetid);



	spin_lock_init(&smcd->lock);

	spin_lock_init(&smcd->lgr_lock);

	INIT_LIST_HEAD(&smcd->vlan);

	INIT_LIST_HEAD(&smcd->lgr_list);

	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",