From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Simmons Date: Sun, 24 Feb 2019 17:00:58 +0000 (GMT) Subject: [lustre-devel] [PATCH 06/37] lustre: obd_type: discard obd_types linked list. In-Reply-To: <155053494516.24125.10480743535229018309.stgit@noble.brown> References: <155053473693.24125.6976971762921761309.stgit@noble.brown> <155053494516.24125.10480743535229018309.stgit@noble.brown> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org > As all obd_types are kobjects in the lustre_kset kset, > they are linked together in that kset and don't > need any extra linkage. > > As kset_find_obj() returns a counted reference, we need > to put that reference when done. > > Signed-off-by: NeilBrown > --- > drivers/staging/lustre/lustre/include/obd.h | 1 - > drivers/staging/lustre/lustre/obdclass/genops.c | 41 +++++++++++------------ > 2 files changed, 19 insertions(+), 23 deletions(-) > > diff --git a/drivers/staging/lustre/lustre/include/obd.h b/drivers/staging/lustre/lustre/include/obd.h > index 3aa9cc889949..50f33f400075 100644 > --- a/drivers/staging/lustre/lustre/include/obd.h > +++ b/drivers/staging/lustre/lustre/include/obd.h > @@ -99,7 +99,6 @@ struct obd_info { > }; > > struct obd_type { > - struct list_head typ_chain; > struct obd_ops *typ_dt_ops; > struct md_ops *typ_md_ops; > struct dentry *typ_debugfs_entry; > diff --git a/drivers/staging/lustre/lustre/obdclass/genops.c b/drivers/staging/lustre/lustre/obdclass/genops.c > index 32581f1a92ac..775e4fa4f6a8 100644 > --- a/drivers/staging/lustre/lustre/obdclass/genops.c > +++ b/drivers/staging/lustre/lustre/obdclass/genops.c > @@ -42,8 +42,6 @@ > #include > #include > > -static DEFINE_SPINLOCK(obd_types_lock); > -static LIST_HEAD(obd_types); > DEFINE_RWLOCK(obd_dev_lock); > static struct obd_device *obd_devs[MAX_OBD_DEVICES]; > > @@ -88,22 +86,19 @@ static void obd_device_free(struct obd_device *obd) > > static struct obd_type *class_search_type(const char *name) > { > - struct obd_type *type; > + struct kobject *kobj = kset_find_obj(lustre_kset, name); > + > + if (kobj) > + return container_of(kobj, struct obd_type, typ_kobj); > > - spin_lock(&obd_types_lock); > - list_for_each_entry(type, &obd_types, typ_chain) { > - if (strcmp(type->typ_name, name) == 0) { > - spin_unlock(&obd_types_lock); > - return type; > - } > - } > - spin_unlock(&obd_types_lock); > return NULL; > } > > static struct obd_type *class_get_type(const char *name) > { > - struct obd_type *type = class_search_type(name); > + struct obd_type *type; > + > + type = class_search_type(name); > > if (!type) { > const char *modname = name; > @@ -121,6 +116,11 @@ static struct obd_type *class_get_type(const char *name) > type->typ_refcnt++; > try_module_get(type->typ_dt_ops->owner); > spin_unlock(&type->obd_type_lock); > + /* class_search_type() returned a counted reference, > + * but we don't need that count any more as > + * we have one through typ_refcnt. > + */ > + kobject_put(&type->typ_kobj); > } > return type; > } > @@ -143,10 +143,6 @@ static void class_sysfs_release(struct kobject *kobj) > if (type->typ_lu) > lu_device_type_fini(type->typ_lu); > > - spin_lock(&obd_types_lock); > - list_del(&type->typ_chain); > - spin_unlock(&obd_types_lock); > - > kfree(type->typ_md_ops); > kfree(type->typ_dt_ops); > kfree(type); > @@ -169,8 +165,10 @@ int class_register_type(struct obd_ops *dt_ops, struct md_ops *md_ops, > /* sanity check */ > LASSERT(strnlen(name, CLASS_MAX_NAME) < CLASS_MAX_NAME); > > - if (class_search_type(name)) { > + type = class_search_type(name); > + if (type) { > CDEBUG(D_IOCTL, "Type %s already registered\n", name); > + kobject_put(&type->typ_kobj); > return -EEXIST; > } > > @@ -181,7 +179,6 @@ int class_register_type(struct obd_ops *dt_ops, struct md_ops *md_ops, > > type->typ_kobj.kset = lustre_kset; > kobject_init(&type->typ_kobj, &class_ktype); > - INIT_LIST_HEAD(&type->typ_chain); > > type->typ_dt_ops = kzalloc(sizeof(*type->typ_dt_ops), GFP_NOFS); > type->typ_md_ops = kzalloc(sizeof(*type->typ_md_ops), GFP_NOFS); > @@ -210,10 +207,6 @@ int class_register_type(struct obd_ops *dt_ops, struct md_ops *md_ops, > goto failed; > } > > - spin_lock(&obd_types_lock); > - list_add(&type->typ_chain, &obd_types); > - spin_unlock(&obd_types_lock); > - > return 0; > > failed: > @@ -238,9 +231,13 @@ int class_unregister_type(const char *name) > /* Remove ops, but leave the name for debugging */ > kfree(type->typ_dt_ops); > kfree(type->typ_md_ops); > + kobject_put(&type->typ_kobj); > return -EBUSY; > } > > + /* Put the ref returned by class_search_type() */ > + kobject_put(&type->typ_kobj); > + /* Put the final ref */ > kobject_put(&type->typ_kobj); This last part needs to be kobject_del(&type->typ_kobj); but that will be handled in the early patch. > return 0; > > >