From ec0bddbc5574ea5903cec8f30ed57777f14d86a8 Mon Sep 17 00:00:00 2001 From: Philipp Reisner Date: Wed, 4 May 2011 15:47:01 +0200 Subject: [PATCH] drbd: Use RCU for the drbd_tconns list Preparing removal of drbd_cfg_rwsem Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_main.c | 7 ++++--- drivers/block/drbd/drbd_nl.c | 12 +++++++----- 2 files changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 8da0e99..771b53e 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -2341,7 +2341,7 @@ static void drbd_cleanup(void) } list_for_each_entry_safe(tconn, tmp, &drbd_tconns, all_tconn) { - list_del(&tconn->all_tconn); + list_del_rcu(&tconn->all_tconn); synchronize_rcu(); kref_put(&tconn->kref, &conn_destroy); } @@ -2409,7 +2409,7 @@ struct drbd_tconn *conn_get_by_name(const char *name) return NULL; down_read(&drbd_cfg_rwsem); - list_for_each_entry(tconn, &drbd_tconns, all_tconn) { + list_for_each_entry_rcu(tconn, &drbd_tconns, all_tconn) { if (!strcmp(tconn->name, name)) { kref_get(&tconn->kref); goto found; @@ -2459,6 +2459,7 @@ void conn_free_crypto(struct drbd_tconn *tconn) tconn->int_dig_vv = NULL; } +/* caller must be under genl_lock() */ struct drbd_tconn *conn_create(const char *name) { struct drbd_tconn *tconn; @@ -2503,7 +2504,7 @@ struct drbd_tconn *conn_create(const char *name) down_write(&drbd_cfg_rwsem); kref_init(&tconn->kref); - list_add_tail(&tconn->all_tconn, &drbd_tconns); + list_add_tail_rcu(&tconn->all_tconn, &drbd_tconns); up_write(&drbd_cfg_rwsem); return tconn; diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index 5747bc6..a0cf000 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -2674,7 +2674,7 @@ int get_one_status(struct sk_buff *skb, struct netlink_callback *cb) /* synchronize with conn_create()/conn_destroy() */ down_read(&drbd_cfg_rwsem); /* revalidate iterator position */ - list_for_each_entry(tmp, &drbd_tconns, all_tconn) { + list_for_each_entry_rcu(tmp, &drbd_tconns, all_tconn) { if (pos == NULL) { /* first iteration */ pos = tmp; @@ -2692,8 +2692,8 @@ next_tconn: if (!mdev) { /* No more volumes to dump on this tconn. * Advance tconn iterator. */ - pos = list_entry(tconn->all_tconn.next, - struct drbd_tconn, all_tconn); + pos = list_entry_rcu(tconn->all_tconn.next, + struct drbd_tconn, all_tconn); /* Did we dump any volume on this tconn yet? */ if (volume != 0) { /* If we reached the end of the list, @@ -3130,7 +3130,8 @@ int drbd_adm_down(struct sk_buff *skb, struct genl_info *info) /* delete connection */ if (conn_lowest_minor(adm_ctx.tconn) < 0) { - list_del(&adm_ctx.tconn->all_tconn); + list_del_rcu(&adm_ctx.tconn->all_tconn); + synchronize_rcu(); kref_put(&adm_ctx.tconn->kref, &conn_destroy); retcode = NO_ERROR; @@ -3160,7 +3161,8 @@ int drbd_adm_delete_connection(struct sk_buff *skb, struct genl_info *info) down_write(&drbd_cfg_rwsem); if (conn_lowest_minor(adm_ctx.tconn) < 0) { - list_del(&adm_ctx.tconn->all_tconn); + list_del_rcu(&adm_ctx.tconn->all_tconn); + synchronize_rcu(); kref_put(&adm_ctx.tconn->kref, &conn_destroy); retcode = NO_ERROR; -- 2.7.4