LU-56 lnet: code cleanup for lib-md.c

This patch just did some code cleanup for lib-md.c, it's an
intermediate patch for LNet SMP improvements.

Signed-off-by: Liang Zhen <liang@whamcloud.com>
Change-Id: I5d162852008284ae08f3b9e7935c9251b245fb5c
Reviewed-on: http://review.whamcloud.com/3010
Tested-by: Hudson
Reviewed-by: Doug Oucharek <doug@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Bobi Jam <bobijam@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>

diff --git a/lnet/lnet/lib-md.c b/lnet/lnet/lib-md.c
index 137299c..87b2613 100644 (file)
--- a/lnet/lnet/lib-md.c
+++ b/lnet/lnet/lib-md.c
@@ -80,42 +80,20 @@ lnet_md_unlink(lnet_libmd_t *md)
        lnet_md_free_locked(md);
 }
 
        lnet_md_free_locked(md);
 }
 

-/* must be called with LNET_LOCK held */

 static int
 static int

-lib_md_build(lnet_libmd_t *lmd, lnet_md_t *umd, int unlink)
+lnet_md_build(lnet_libmd_t *lmd, lnet_md_t *umd, int unlink)

 {
 {

-        lnet_eq_t   *eq = NULL;

         int          i;
         unsigned int niov;
         int          total_length = 0;
 
         int          i;
         unsigned int niov;
         int          total_length = 0;
 

-        /* NB we are passed an allocated, but uninitialised/active md.
-         * if we return success, caller may lnet_md_unlink() it.
-         * otherwise caller may only lnet_md_free() it.
-         */
-
-        if (!LNetHandleIsInvalid (umd->eq_handle)) {
-                eq = lnet_handle2eq(&umd->eq_handle);
-                if (eq == NULL)
-                        return -ENOENT;
-        }
-
-        /* This implementation doesn't know how to create START events or
-         * disable END events.  Best to LASSERT our caller is compliant so
-         * we find out quickly...  */
-        /*  TODO - reevaluate what should be here in light of 
-         * the removal of the start and end events
-         * maybe there we shouldn't even allow LNET_EQ_NONE!)
-        LASSERT (eq == NULL);
-         */
-

         lmd->md_me = NULL;
         lmd->md_start = umd->start;
         lmd->md_offset = 0;
         lmd->md_max_size = umd->max_size;
         lmd->md_options = umd->options;
         lmd->md_user_ptr = umd->user_ptr;
         lmd->md_me = NULL;
         lmd->md_start = umd->start;
         lmd->md_offset = 0;
         lmd->md_max_size = umd->max_size;
         lmd->md_options = umd->options;
         lmd->md_user_ptr = umd->user_ptr;

-        lmd->md_eq = eq;
+       lmd->md_eq = NULL;

         lmd->md_threshold = umd->threshold;
         lmd->md_refcount = 0;
         lmd->md_flags = (unlink == LNET_UNLINK) ? LNET_MD_FLAG_AUTO_UNLINK : 0;
         lmd->md_threshold = umd->threshold;
         lmd->md_refcount = 0;
         lmd->md_flags = (unlink == LNET_UNLINK) ? LNET_MD_FLAG_AUTO_UNLINK : 0;


@@ -180,13 +158,40 @@ lib_md_build(lnet_libmd_t *lmd, lnet_md_t *umd, int unlink)
                         return -EINVAL;
         }
 
                         return -EINVAL;
         }
 

-        if (eq != NULL)
-                eq->eq_refcount++;
+       return 0;
+}

 
 

-        /* It's good; let handle2md succeed and add to active mds */
-       lnet_res_lh_initialize(&the_lnet.ln_md_container, &lmd->md_lh);
-       LASSERT(cfs_list_empty(&lmd->md_list));
-       cfs_list_add(&lmd->md_list, &the_lnet.ln_md_container.rec_active);
+/* must be called with resource lock held */
+static int
+lnet_md_link(lnet_libmd_t *md, lnet_handle_eq_t eq_handle)
+{
+       struct lnet_res_container *container = &the_lnet.ln_md_container;
+
+       /* NB we are passed an allocated, but inactive md.
+        * if we return success, caller may lnet_md_unlink() it.
+        * otherwise caller may only lnet_md_free() it.
+        */
+       /* This implementation doesn't know how to create START events or
+        * disable END events.  Best to LASSERT our caller is compliant so
+        * we find out quickly...  */
+       /*  TODO - reevaluate what should be here in light of
+        * the removal of the start and end events
+        * maybe there we shouldn't even allow LNET_EQ_NONE!)
+        * LASSERT (eq == NULL);
+        */
+       if (!LNetHandleIsInvalid(eq_handle)) {
+               md->md_eq = lnet_handle2eq(&eq_handle);
+
+               if (md->md_eq == NULL)
+                       return -ENOENT;
+
+               md->md_eq->eq_refcount++;
+       }
+
+       lnet_res_lh_initialize(container, &md->md_lh);
+
+       LASSERT(cfs_list_empty(&md->md_list));
+       cfs_list_add(&md->md_list, &container->rec_active);

 
        return 0;
 }
 
        return 0;
 }


@@ -277,35 +282,41 @@ LNetMDAttach(lnet_handle_me_t meh, lnet_md_t umd,
         if (md == NULL)
                 return -ENOMEM;
 
         if (md == NULL)
                 return -ENOMEM;
 

-        LNET_LOCK();
+       rc = lnet_md_build(md, &umd, unlink);
+
+       LNET_LOCK();
+       if (rc != 0)
+               goto failed;

 
         me = lnet_handle2me(&meh);
 
         me = lnet_handle2me(&meh);

-        if (me == NULL) {
-                rc = -ENOENT;
-        } else if (me->me_md != NULL) {
+       if (me == NULL)
+               rc = -ENOENT;
+       else if (me->me_md != NULL)

                 rc = -EBUSY;
                 rc = -EBUSY;

-        } else {
-                rc = lib_md_build(md, &umd, unlink);
-                if (rc == 0) {
-                       the_lnet.ln_portals[me->me_portal]->ptl_ml_version++;
+       else
+               rc = lnet_md_link(md, umd.eq_handle);

 
 

-                        me->me_md = md;
-                        md->md_me = me;
+       if (rc != 0)
+               goto failed;

 
 

-                        lnet_md2handle(handle, md);
+       the_lnet.ln_portals[me->me_portal]->ptl_ml_version++;

 
 

-                        /* check if this MD matches any blocked msgs */
-                        lnet_match_blocked_msg(md);   /* expects LNET_LOCK held */
+       me->me_md = md;
+       md->md_me = me;

 
 

-                        LNET_UNLOCK();
-                        return (0);
-                }
-        }
+       lnet_md2handle(handle, md);
+
+       /* check if this MD matches any blocked msgs */
+       lnet_match_blocked_msg(md);   /* expects LNET_LOCK held */

 
 

+       LNET_UNLOCK();
+       return 0;
+
+ failed:

        lnet_md_free_locked(md);
 
        lnet_md_free_locked(md);
 

-        LNET_UNLOCK();
-        return (rc);
+       LNET_UNLOCK();
+       return rc;

 }
 
 /**
 }
 
 /**


@@ -345,21 +356,26 @@ LNetMDBind(lnet_md_t umd, lnet_unlink_t unlink, lnet_handle_md_t *handle)
         if (md == NULL)
                 return -ENOMEM;
 
         if (md == NULL)
                 return -ENOMEM;
 

-        LNET_LOCK();
+       rc = lnet_md_build(md, &umd, unlink);

 
 

-        rc = lib_md_build(md, &umd, unlink);
+       LNET_LOCK();
+       if (rc != 0)
+               goto failed;

 
 

-        if (rc == 0) {
-                lnet_md2handle(handle, md);
+       rc = lnet_md_link(md, umd.eq_handle);
+       if (rc != 0)
+               goto failed;

 
 

-                LNET_UNLOCK();
-                return (0);
-        }
+       lnet_md2handle(handle, md);

 
 

+       LNET_UNLOCK();
+       return 0;
+
+ failed:

        lnet_md_free_locked(md);
 
        lnet_md_free_locked(md);
 

-        LNET_UNLOCK();
-        return (rc);
+       LNET_UNLOCK();
+       return rc;

 }
 
 /**
 }
 
 /**