LU-3059 lu: shrink lu_object by 8 bytes on x86_64

Remove the lo_depth member from struct lu_object.  This field is never
set and only read in lu_object_print().  Remove the lo_flags member.
This field was only used in lu_object_alloc() and can be replaced with
an on-stack mask to keep trace of which layers have been allocated.

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: I998cfda0234f4c418227c9ba640850a78ca7893e
Reviewed-on: http://review.whamcloud.com/5890
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/include/lu_object.h b/lustre/include/lu_object.h
index 85dcbfa..bd0e58d 100644 (file)
--- a/lustre/include/lu_object.h
+++ b/lustre/include/lu_object.h
@@ -398,17 +398,6 @@ static inline int lu_device_is_md(const struct lu_device *d)
 }
 
 /**
- * Flags for the object layers.
- */
-enum lu_object_flags {
-        /**
-         * this flags is set if lu_object_operations::loo_object_init() has
-         * been called for this layer. Used by lu_object_alloc().
-         */
-        LU_OBJECT_ALLOCATED = (1 << 0)
-};
-
-/**
  * Common object attributes.
  */
 struct lu_attr {
@@ -485,14 +474,6 @@ struct lu_object {
          * Linkage into list of all layers.
          */
         cfs_list_t                         lo_linkage;
-        /**
-         * Depth. Top level layer depth is 0.
-         */
-        int                                lo_depth;
-       /**
-        * Flags from enum lu_object_flags.
-        */
-       __u32                                   lo_flags;
        /**
         * Link to the device, for debugging.
         */

diff --git a/lustre/obdclass/lu_object.c b/lustre/obdclass/lu_object.c
index ba45a0d..cb2da24 100644 (file)
--- a/lustre/obdclass/lu_object.c
+++ b/lustre/obdclass/lu_object.c
@@ -195,16 +195,18 @@ EXPORT_SYMBOL(lu_object_unhash);
  * struct lu_device_operations definition.
  */
 static struct lu_object *lu_object_alloc(const struct lu_env *env,
-                                         struct lu_device *dev,
-                                         const struct lu_fid *f,
-                                         const struct lu_object_conf *conf)
-{
-        struct lu_object *scan;
-        struct lu_object *top;
-        cfs_list_t *layers;
-        int clean;
-        int result;
-        ENTRY;
+                                        struct lu_device *dev,
+                                        const struct lu_fid *f,
+                                        const struct lu_object_conf *conf)
+{
+       struct lu_object *scan;
+       struct lu_object *top;
+       cfs_list_t *layers;
+       unsigned int init_mask = 0;
+       unsigned int init_flag;
+       int clean;
+       int result;
+       ENTRY;
 
        /*
         * Create top-level object slice. This will also create
@@ -221,25 +223,29 @@ static struct lu_object *lu_object_alloc(const struct lu_env *env,
          */
         top->lo_header->loh_fid = *f;
         layers = &top->lo_header->loh_layers;
-        do {
-                /*
-                 * Call ->loo_object_init() repeatedly, until no more new
-                 * object slices are created.
-                 */
-                clean = 1;
-                cfs_list_for_each_entry(scan, layers, lo_linkage) {
-                        if (scan->lo_flags & LU_OBJECT_ALLOCATED)
-                                continue;
-                        clean = 0;
-                        scan->lo_header = top->lo_header;
-                        result = scan->lo_ops->loo_object_init(env, scan, conf);
-                        if (result != 0) {
-                                lu_object_free(env, top);
-                                RETURN(ERR_PTR(result));
-                        }
-                        scan->lo_flags |= LU_OBJECT_ALLOCATED;
-                }
-        } while (!clean);
+
+       do {
+               /*
+                * Call ->loo_object_init() repeatedly, until no more new
+                * object slices are created.
+                */
+               clean = 1;
+               init_flag = 1;
+               cfs_list_for_each_entry(scan, layers, lo_linkage) {
+                       if (init_mask & init_flag)
+                               goto next;
+                       clean = 0;
+                       scan->lo_header = top->lo_header;
+                       result = scan->lo_ops->loo_object_init(env, scan, conf);
+                       if (result != 0) {
+                               lu_object_free(env, top);
+                               RETURN(ERR_PTR(result));
+                       }
+                       init_mask |= init_flag;
+next:
+                       init_flag <<= 1;
+               }
+       } while (!clean);
 
         cfs_list_for_each_entry_reverse(scan, layers, lo_linkage) {
                 if (scan->lo_ops->loo_object_start != NULL) {
@@ -486,28 +492,30 @@ EXPORT_SYMBOL(lu_object_header_print);
  * Print human readable representation of the \a o to the \a printer.
  */
 void lu_object_print(const struct lu_env *env, void *cookie,
-                     lu_printer_t printer, const struct lu_object *o)
+                    lu_printer_t printer, const struct lu_object *o)
 {
-        static const char ruler[] = "........................................";
-        struct lu_object_header *top;
-        int depth;
+       static const char ruler[] = "........................................";
+       struct lu_object_header *top;
+       int depth = 4;
 
-        top = o->lo_header;
-        lu_object_header_print(env, cookie, printer, top);
-        (*printer)(env, cookie, "{ \n");
-        cfs_list_for_each_entry(o, &top->loh_layers, lo_linkage) {
-                depth = o->lo_depth + 4;
+       top = o->lo_header;
+       lu_object_header_print(env, cookie, printer, top);
+       (*printer)(env, cookie, "{\n");
 
-                /*
-                 * print `.' \a depth times followed by type name and address
-                 */
-                (*printer)(env, cookie, "%*.*s%s@%p", depth, depth, ruler,
-                           o->lo_dev->ld_type->ldt_name, o);
-                if (o->lo_ops->loo_object_print != NULL)
-                        o->lo_ops->loo_object_print(env, cookie, printer, o);
-                (*printer)(env, cookie, "\n");
-        }
-        (*printer)(env, cookie, "} header@%p\n", top);
+       cfs_list_for_each_entry(o, &top->loh_layers, lo_linkage) {
+               /*
+                * print `.' \a depth times followed by type name and address
+                */
+               (*printer)(env, cookie, "%*.*s%s@%p", depth, depth, ruler,
+                          o->lo_dev->ld_type->ldt_name, o);
+
+               if (o->lo_ops->loo_object_print != NULL)
+                       (*o->lo_ops->loo_object_print)(env, cookie, printer, o);
+
+               (*printer)(env, cookie, "\n");
+       }
+
+       (*printer)(env, cookie, "} header@%p\n", top);
 }
 EXPORT_SYMBOL(lu_object_print);