LU-8066 obd: embed typ_kobj in obd_type

As there is a 1-1 mapping between obd_types and their ->typ_kobj, it
is simple and more normal to embed the kobj in the obd_type, rather
than allocate it separately.

This requires calling "kobject_init_and_add()" earlier, so we
open-code relevant part of class_setup_tunables() in
class_register_type(). Now class_setup_tunables() is needed only
for server side code.

With typ_kobj embedded in obd_type we change class_setup_tunables()
to return an obd_type object instead of a kobject. This way we
can use kobject_put() to cleanup the obd_type created with
class_setup_tunables(). The reason for class_setup_tunables() is
for the creation of a lightweight obd_type which is never added
to the typ_chain list to avoid potential duplicates which can
happen on single node setups with lod / lov and osp /osc.

Change-Id: Iac160e6817a7c520e4462a3fc133ddfee6a7ccdc
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/34612
Reviewed-by: Ben Evans <bevans@cray.com>
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/include/obd.h b/lustre/include/obd.h
index 44c6ced..4466d63 100644 (file)
--- a/lustre/include/obd.h
+++ b/lustre/include/obd.h
@@ -110,7 +110,7 @@ struct obd_type {
        int                      typ_refcnt;
        struct lu_device_type   *typ_lu;
        spinlock_t               obd_type_lock;
-       struct kobject          *typ_kobj;
+       struct kobject           typ_kobj;
 };
 
 struct brw_page {

diff --git a/lustre/include/obd_class.h b/lustre/include/obd_class.h
index d0e4a0d..359e7ef 100644 (file)
--- a/lustre/include/obd_class.h
+++ b/lustre/include/obd_class.h
@@ -63,7 +63,9 @@ struct lu_device_type;
 
 /* genops.c */
 struct obd_export *class_conn2export(struct lustre_handle *);
-struct kobject *class_setup_tunables(const char *name);
+#ifdef HAVE_SERVER_SUPPORT
+struct obd_type *class_setup_tunables(const char *name);
+#endif
 int class_register_type(struct obd_ops *, struct md_ops *, bool enable_proc,
                        struct lprocfs_vars *module_vars,
                        const char *nm, struct lu_device_type *ldt);

diff --git a/lustre/lod/lod_dev.c b/lustre/lod/lod_dev.c
index 96e0e2a..8285524 100644 (file)
--- a/lustre/lod/lod_dev.c
+++ b/lustre/lod/lod_dev.c
@@ -2223,13 +2223,12 @@ static struct obd_ops lod_obd_device_ops = {
        .o_pool_del     = lod_pool_del,
 };
 
-static struct obd_type sym;
+static struct obd_type *sym;
 
 static int __init lod_init(void)
 {
        struct dentry *symlink;
        struct obd_type *type;
-       struct kobject *kobj;
        struct qstr dname;
        int rc;
 
@@ -2244,6 +2243,15 @@ static int __init lod_init(void)
                return rc;
        }
 
+       sym = class_setup_tunables(LUSTRE_LOV_NAME);
+       if (IS_ERR(sym)) {
+               rc = PTR_ERR(sym);
+               /* does real "lov" already exist ? */
+               if (rc == -EEXIST)
+                       GOTO(try_proc, rc = 0);
+               GOTO(no_lov, rc);
+       }
+
        /* create "lov" entry for compatibility purposes */
        dname.name = "lov";
        dname.len = strlen(dname.name);
@@ -2256,26 +2264,11 @@ static int __init lod_init(void)
                        rc = symlink ? PTR_ERR(symlink) : -ENOMEM;
                        GOTO(no_lov, rc);
                }
-               sym.typ_debugfs_entry = symlink;
+               sym->typ_debugfs_entry = symlink;
        } else {
                dput(symlink);
        }
 
-       kobj = kset_find_obj(lustre_kset, dname.name);
-       if (kobj) {
-               kobject_put(kobj);
-               goto try_proc;
-       }
-
-       kobj = class_setup_tunables(dname.name);
-       if (IS_ERR(kobj)) {
-               rc = PTR_ERR(kobj);
-               if (sym.typ_debugfs_entry)
-                       ldebugfs_remove(&sym.typ_debugfs_entry);
-               GOTO(no_lov, rc);
-       }
-       sym.typ_kobj = kobj;
-
 try_proc:
        type = class_search_type(LUSTRE_LOV_NAME);
        if (type && type->typ_procroot)
@@ -2295,8 +2288,10 @@ no_lov:
 
 static void __exit lod_exit(void)
 {
-       ldebugfs_remove(&sym.typ_debugfs_entry);
-       kobject_put(sym.typ_kobj);
+       if (!IS_ERR_OR_NULL(sym)) {
+               ldebugfs_remove(&sym->typ_debugfs_entry);
+               kobject_put(&sym->typ_kobj);
+       }
        class_unregister_type(LUSTRE_LOD_NAME);
        lu_kmem_fini(lod_caches);
 }

diff --git a/lustre/mdd/mdd_lproc.c b/lustre/mdd/mdd_lproc.c
index e53283b..d17d3c9 100644 (file)
--- a/lustre/mdd/mdd_lproc.c
+++ b/lustre/mdd/mdd_lproc.c
@@ -590,7 +590,7 @@ int mdd_procfs_init(struct mdd_device *mdd, const char *name)
 
        init_completion(&mdd->mdd_kobj_unregister);
        rc = kobject_init_and_add(&mdd->mdd_kobj, &mdd->mdd_ktype,
-                                 type->typ_kobj, "%s", name);
+                                 &type->typ_kobj, "%s", name);
        if (rc)
                return rc;
 

diff --git a/lustre/obdclass/dt_object.c b/lustre/obdclass/dt_object.c
index 9cacbe8..5cea5a6 100644 (file)
--- a/lustre/obdclass/dt_object.c
+++ b/lustre/obdclass/dt_object.c
@@ -1265,7 +1265,7 @@ int dt_tunables_init(struct dt_device *dt, struct obd_type *type,
        dt->dd_ktype.release = dt_sysfs_release;
 
        init_completion(&dt->dd_kobj_unregister);
-       rc = kobject_init_and_add(&dt->dd_kobj, &dt->dd_ktype, type->typ_kobj,
+       rc = kobject_init_and_add(&dt->dd_kobj, &dt->dd_ktype, &type->typ_kobj,
                                  "%s", name);
        if (rc)
                return rc;

diff --git a/lustre/obdclass/genops.c b/lustre/obdclass/genops.c
index 0a840c9..9508495 100644 (file)
--- a/lustre/obdclass/genops.c
+++ b/lustre/obdclass/genops.c
@@ -160,7 +160,9 @@ void class_put_type(struct obd_type *type)
 
 static void class_sysfs_release(struct kobject *kobj)
 {
-       OBD_FREE(kobj, sizeof(*kobj));
+       struct obd_type *type = container_of(kobj, struct obd_type, typ_kobj);
+
+       OBD_FREE(type, sizeof(*type));
 }
 
 static struct kobj_type class_ktype = {
@@ -168,30 +170,34 @@ static struct kobj_type class_ktype = {
        .release        = class_sysfs_release,
 };
 
-struct kobject *class_setup_tunables(const char *name)
+#ifdef HAVE_SERVER_SUPPORT
+struct obd_type *class_setup_tunables(const char *name)
 {
+       struct obd_type *type;
        struct kobject *kobj;
        int rc;
 
-#ifdef HAVE_SERVER_SUPPORT
        kobj = kset_find_obj(lustre_kset, name);
-       if (kobj)
-               return kobj;
-#endif
-       OBD_ALLOC(kobj, sizeof(*kobj));
-       if (!kobj)
+       if (kobj) {
+               kobject_put(kobj);
+               return ERR_PTR(-EEXIST);
+       }
+
+       OBD_ALLOC(type, sizeof(*type));
+       if (!type)
                return ERR_PTR(-ENOMEM);
 
-       kobj->kset = lustre_kset;
-       kobject_init(kobj, &class_ktype);
-       rc = kobject_add(kobj, &lustre_kset->kobj, "%s", name);
+       type->typ_kobj.kset = lustre_kset;
+       kobject_init(&type->typ_kobj, &class_ktype);
+       rc = kobject_add(&type->typ_kobj, &lustre_kset->kobj, "%s", name);
        if (rc) {
-               kobject_put(kobj);
+               kobject_put(&type->typ_kobj);
                return ERR_PTR(rc);
        }
-       return kobj;
+       return type;
 }
 EXPORT_SYMBOL(class_setup_tunables);
+#endif /* HAVE_SERVER_SUPPORT */
 
 #define CLASS_MAX_NAME 1024
 
@@ -201,9 +207,9 @@ int class_register_type(struct obd_ops *dt_ops, struct md_ops *md_ops,
 {
        struct obd_type *type;
 #ifdef HAVE_SERVER_SUPPORT
-       struct qstr dname;
+       struct kobject *kobj;
 #endif /* HAVE_SERVER_SUPPORT */
-       int rc = 0;
+       int rc;
 
        ENTRY;
        /* sanity check */
@@ -214,11 +220,36 @@ int class_register_type(struct obd_ops *dt_ops, struct md_ops *md_ops,
                 RETURN(-EEXIST);
         }
 
-        rc = -ENOMEM;
+#ifdef HAVE_SERVER_SUPPORT
+       kobj = kset_find_obj(lustre_kset, name);
+       if (kobj) {
+               type = container_of(kobj, struct obd_type, typ_kobj);
+
+               goto dir_exist;
+       }
+#endif /* HAVE_SERVER_SUPPORT */
+
         OBD_ALLOC(type, sizeof(*type));
         if (type == NULL)
-                RETURN(rc);
+               RETURN(-ENOMEM);
+
+       type->typ_kobj.kset = lustre_kset;
+       rc = kobject_init_and_add(&type->typ_kobj, &class_ktype,
+                                 &lustre_kset->kobj, "%s", name);
+       if (rc)
+               GOTO(failed, rc);
 
+       type->typ_debugfs_entry = ldebugfs_register(name, debugfs_lustre_root,
+                                                   vars, type);
+       if (IS_ERR_OR_NULL(type->typ_debugfs_entry)) {
+               rc = type->typ_debugfs_entry ? PTR_ERR(type->typ_debugfs_entry)
+                                            : -ENOMEM;
+               type->typ_debugfs_entry = NULL;
+               GOTO(failed, rc);
+       }
+#ifdef HAVE_SERVER_SUPPORT
+dir_exist:
+#endif /* HAVE_SERVER_SUPPORT */
         OBD_ALLOC_PTR(type->typ_dt_ops);
         OBD_ALLOC_PTR(type->typ_md_ops);
         OBD_ALLOC(type->typ_name, strlen(name) + 1);
@@ -236,7 +267,7 @@ int class_register_type(struct obd_ops *dt_ops, struct md_ops *md_ops,
        spin_lock_init(&type->obd_type_lock);
 
 #ifdef CONFIG_PROC_FS
-       if (enable_proc) {
+       if (enable_proc && !type->typ_procroot) {
                type->typ_procroot = lprocfs_register(type->typ_name,
                                                      proc_lustre_root,
                                                      NULL, type);
@@ -247,42 +278,11 @@ int class_register_type(struct obd_ops *dt_ops, struct md_ops *md_ops,
                }
        }
 #endif
-#ifdef HAVE_SERVER_SUPPORT
-       dname.name = name;
-       dname.len = strlen(dname.name);
-       dname.hash = ll_full_name_hash(debugfs_lustre_root, dname.name,
-                                      dname.len);
-       type->typ_debugfs_entry = d_lookup(debugfs_lustre_root, &dname);
-       if (type->typ_debugfs_entry) {
-               dput(type->typ_debugfs_entry);
-               type->typ_sym_filter = true;
-               goto dir_exist;
-       }
-#endif /* HAVE_SERVER_SUPPORT */
-
-       type->typ_debugfs_entry = ldebugfs_register(type->typ_name,
-                                                   debugfs_lustre_root,
-                                                   vars, type);
-       if (IS_ERR_OR_NULL(type->typ_debugfs_entry)) {
-               rc = type->typ_debugfs_entry ? PTR_ERR(type->typ_debugfs_entry)
-                                            : -ENOMEM;
-               type->typ_debugfs_entry = NULL;
-               GOTO(failed, rc);
-       }
-#ifdef HAVE_SERVER_SUPPORT
-dir_exist:
-#endif
-       type->typ_kobj = class_setup_tunables(type->typ_name);
-       if (IS_ERR(type->typ_kobj))
-               GOTO(failed, rc = PTR_ERR(type->typ_kobj));
-
        if (ldt) {
                type->typ_lu = ldt;
                rc = lu_device_type_init(ldt);
-               if (rc) {
-                       kobject_put(type->typ_kobj);
+               if (rc)
                        GOTO(failed, rc);
-               }
        }
 
        spin_lock(&obd_types_lock);
@@ -309,8 +309,9 @@ failed:
                 OBD_FREE_PTR(type->typ_md_ops);
         if (type->typ_dt_ops != NULL)
                 OBD_FREE_PTR(type->typ_dt_ops);
-        OBD_FREE(type, sizeof(*type));
-        RETURN(rc);
+       kobject_put(&type->typ_kobj);
+
+       RETURN(rc);
 }
 EXPORT_SYMBOL(class_register_type);
 
@@ -333,8 +334,6 @@ int class_unregister_type(const char *name)
                 RETURN(-EBUSY);
         }
 
-       kobject_put(type->typ_kobj);
-
        /* we do not use type->typ_procroot as for compatibility purposes
         * other modules can share names (i.e. lod can use lov entry). so
         * we can't reference pointer as it can get invalided when another
@@ -363,8 +362,9 @@ int class_unregister_type(const char *name)
                 OBD_FREE_PTR(type->typ_dt_ops);
         if (type->typ_md_ops != NULL)
                 OBD_FREE_PTR(type->typ_md_ops);
-        OBD_FREE(type, sizeof(*type));
-        RETURN(0);
+       kobject_put(&type->typ_kobj);
+
+       RETURN(0);
 } /* class_unregister_type */
 EXPORT_SYMBOL(class_unregister_type);
 

diff --git a/lustre/obdclass/lprocfs_status.c b/lustre/obdclass/lprocfs_status.c
index aa2925a..6c5d61f 100644 (file)
--- a/lustre/obdclass/lprocfs_status.c
+++ b/lustre/obdclass/lprocfs_status.c
@@ -1204,7 +1204,7 @@ int lprocfs_obd_setup(struct obd_device *obd, bool uuid_only)
        obd->obd_ktype.sysfs_ops = &lustre_sysfs_ops;
        obd->obd_ktype.release = obd_sysfs_release;
 
-       obd->obd_kset.kobj.parent = obd->obd_type->typ_kobj;
+       obd->obd_kset.kobj.parent = &obd->obd_type->typ_kobj;
        obd->obd_kset.kobj.ktype = &obd->obd_ktype;
        init_completion(&obd->obd_kobj_unregister);
        rc = kset_register(&obd->obd_kset);

diff --git a/lustre/osp/osp_dev.c b/lustre/osp/osp_dev.c
index b6e88ce..0aaf162 100644 (file)
--- a/lustre/osp/osp_dev.c
+++ b/lustre/osp/osp_dev.c
@@ -1881,7 +1881,7 @@ static struct obd_ops osp_obd_device_ops = {
        .o_fid_alloc    = osp_fid_alloc,
 };
 
-static struct obd_type sym;
+static struct obd_type *sym;
 
 /**
  * Initialize OSP module.
@@ -1899,7 +1899,6 @@ static int __init osp_init(void)
 {
        struct dentry *symlink;
        struct obd_type *type;
-       struct kobject *kobj;
        struct qstr dname;
        int rc;
 
@@ -1922,6 +1921,15 @@ static int __init osp_init(void)
                return rc;
        }
 
+       sym = class_setup_tunables(LUSTRE_OSC_NAME);
+       if (IS_ERR(sym)) {
+               rc = PTR_ERR(sym);
+               /* does real "osc" already exist ? */
+               if (rc == -EEXIST)
+                       GOTO(try_proc, rc = 0);
+               GOTO(no_osc, rc);
+       }
+
        /* create "osc" entry for compatibility purposes */
        dname.name = "osc";
        dname.len = strlen(dname.name);
@@ -1934,26 +1942,11 @@ static int __init osp_init(void)
                        rc = symlink ? PTR_ERR(symlink) : -ENOMEM;
                        GOTO(no_osc, rc);
                }
-               sym.typ_debugfs_entry = symlink;
+               sym->typ_debugfs_entry = symlink;
        } else {
                dput(symlink);
        }
 
-       kobj = kset_find_obj(lustre_kset, dname.name);
-       if (kobj) {
-               kobject_put(kobj);
-               goto try_proc;
-       }
-
-       kobj = class_setup_tunables(dname.name);
-       if (IS_ERR(kobj)) {
-               rc = PTR_ERR(kobj);
-               if (sym.typ_debugfs_entry)
-                       ldebugfs_remove(&sym.typ_debugfs_entry);
-               GOTO(no_osc, rc);
-       }
-       sym.typ_kobj = kobj;
-
 try_proc:
        type = class_search_type(LUSTRE_OSC_NAME);
        if (type != NULL && type->typ_procroot != NULL)
@@ -1979,8 +1972,10 @@ no_osc:
  */
 static void __exit osp_exit(void)
 {
-       ldebugfs_remove(&sym.typ_debugfs_entry);
-       kobject_put(sym.typ_kobj);
+       if (!IS_ERR_OR_NULL(sym)) {
+               ldebugfs_remove(&sym->typ_debugfs_entry);
+               kobject_put(&sym->typ_kobj);
+       }
        class_unregister_type(LUSTRE_LWP_NAME);
        class_unregister_type(LUSTRE_OSP_NAME);
        lu_kmem_fini(osp_caches);