ORNL-24 skip unnecessary client obj hash lookup

The client-side object will be initialized when inode is established
in memory. Such object will be inserted into global hash table for
further using. The caller follows "lookup-alloc-lookup-insert". It is
standard, but maybe unnecessary for some cases. If it is sure that
there is only one caller will insert the new established object, then
we can skip the two lookup, and "alloc-insert" directly.

Signed-off-by: Fan Yong <yong.fan@whamcloud.com>
Change-Id: Ie173c57627b2e5b4ed9b8a93f368d88ba8e54c31
Reviewed-on: http://review.whamcloud.com/1225
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: Jinshan Xiong <jay@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/include/lu_object.h b/lustre/include/lu_object.h
index 2b9424f..ae21d70 100644 (file)
--- a/lustre/include/lu_object.h
+++ b/lustre/include/lu_object.h
@@ -30,6 +30,9 @@
  * Use is subject to license terms.
  */
 /*
+ * Copyright (c) 2011 Whamcloud, Inc.
+ */
+/*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  */
@@ -169,11 +172,23 @@ struct lu_device_operations {
 };
 
 /**
+ * For lu_object_conf flags
+ */
+typedef enum {
+        /* Currently, only used for client-side object initialization. */
+        LOC_F_NEW = 0x1,
+} loc_flags_t;
+
+/**
  * Object configuration, describing particulars of object being created. On
  * server this is not used, as server objects are full identified by fid. On
  * client configuration contains struct lustre_md.
  */
 struct lu_object_conf {
+        /**
+         * Some hints for obj find and alloc.
+         */
+        loc_flags_t     loc_flags;
 };
 
 /**

diff --git a/lustre/lclient/lcommon_cl.c b/lustre/lclient/lcommon_cl.c
index b083a89..f1fe4dd 100644 (file)
--- a/lustre/lclient/lcommon_cl.c
+++ b/lustre/lclient/lcommon_cl.c
@@ -30,6 +30,9 @@
  * Use is subject to license terms.
  */
 /*
+ * Copyright (c) 2011 Whamcloud, Inc.
+ */
+/*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  *
@@ -1158,7 +1161,7 @@ int cl_inode_init(struct inode *inode, struct lustre_md *md)
         struct cl_object     *clob;
         struct lu_site       *site;
         struct lu_fid        *fid;
-        const struct cl_object_conf conf = {
+        struct cl_object_conf conf = {
                 .coc_inode = inode,
                 .u = {
                         .coc_md    = md
@@ -1167,7 +1170,6 @@ int cl_inode_init(struct inode *inode, struct lustre_md *md)
         int result = 0;
         int refcheck;
 
-        /* LASSERT(inode->i_state & I_NEW); */
         LASSERT(md->body->valid & OBD_MD_FLID);
 
         if (!S_ISREG(cl_inode_mode(inode)))
@@ -1183,6 +1185,14 @@ int cl_inode_init(struct inode *inode, struct lustre_md *md)
         LASSERT(fid_is_sane(fid));
 
         if (lli->lli_clob == NULL) {
+                /* clob is slave of inode, empty lli_clob means for new inode,
+                 * there is no clob in cache with the given fid, so it is
+                 * unnecessary to perform lookup-alloc-lookup-insert, just
+                 * alloc and insert directly. */
+#ifdef __KERNEL__
+                LASSERT(inode->i_state & I_NEW);
+#endif
+                conf.coc_lu.loc_flags = LOC_F_NEW;
                 clob = cl_object_find(env, lu2cl_dev(site->ls_top_dev),
                                       fid, &conf);
                 if (!IS_ERR(clob)) {

diff --git a/lustre/obdclass/lu_object.c b/lustre/obdclass/lu_object.c
index f143f9b..3f1e5e7 100644 (file)
--- a/lustre/obdclass/lu_object.c
+++ b/lustre/obdclass/lu_object.c
@@ -30,6 +30,9 @@
  * Use is subject to license terms.
  */
 /*
+ * Copyright (c) 2011 Whamcloud, Inc.
+ */
+/*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  *
@@ -543,6 +546,30 @@ struct lu_object *lu_object_find(const struct lu_env *env,
 }
 EXPORT_SYMBOL(lu_object_find);
 
+static struct lu_object *lu_object_new(const struct lu_env *env,
+                                       struct lu_device *dev,
+                                       const struct lu_fid *f,
+                                       const struct lu_object_conf *conf)
+{
+        struct lu_object        *o;
+        cfs_hash_t              *hs;
+        cfs_hash_bd_t            bd;
+        struct lu_site_bkt_data *bkt;
+
+        o = lu_object_alloc(env, dev, f, conf);
+        if (unlikely(IS_ERR(o)))
+                return o;
+
+        hs = dev->ld_site->ls_obj_hash;
+        cfs_hash_bd_get_and_lock(hs, (void *)f, &bd, 1);
+        bkt = cfs_hash_bd_extra_get(hs, &bd);
+        cfs_hash_bd_add_locked(hs, &bd, &o->lo_header->loh_hash);
+        cfs_list_add_tail(&o->lo_header->loh_lru, &bkt->lsb_lru);
+        bkt->lsb_busy++;
+        cfs_hash_bd_unlock(hs, &bd, 1);
+        return o;
+}
+
 /**
  * Core logic of lu_object_find*() functions.
  */
@@ -572,9 +599,16 @@ static struct lu_object *lu_object_find_try(const struct lu_env *env,
          *     - unlock index;
          *     - return object.
          *
+         * For "LOC_F_NEW" case, we are sure the object is new established.
+         * It is unnecessary to perform lookup-alloc-lookup-insert, instead,
+         * just alloc and insert directly.
+         *
          * If dying object is found during index search, add @waiter to the
          * site wait-queue and return ERR_PTR(-EAGAIN).
          */
+        if (conf != NULL && conf->loc_flags & LOC_F_NEW)
+                return lu_object_new(env, dev, f, conf);
+
         s  = dev->ld_site;
         hs = s->ls_obj_hash;
         cfs_hash_bd_get_and_lock(hs, (void *)f, &bd, 1);