performance/stat-prefetch: lookup path in create if it is not already looked up.

Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 284 (performance actually decreases for 'ls -l' on a directory containing large number of files with stat-prefetch loaded)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=284

1 files changed, 88 insertions, 24 deletions

diff --git a/xlators/performance/stat-prefetch/src/stat-prefetch.c b/xlators/performance/stat-prefetch/src/stat-prefetch.c
index 12101963d..73efb7d96 100644
--- a/xlators/performance/stat-prefetch/src/stat-prefetch.c
+++ b/xlators/performance/stat-prefetch/src/stat-prefetch.c
@@ -1155,51 +1155,115 @@ out:
 
 
 int32_t
+sp_create_helper (call_frame_t *frame,	xlator_t *this,	loc_t *loc,
+                  int32_t flags, mode_t mode, fd_t *fd)
+{
+        uint64_t        value     = 0;
+        sp_inode_ctx_t *inode_ctx = NULL;
+        int32_t         ret       = 0, op_ret = -1, op_errno = -1;
+        
+        ret = inode_ctx_get (loc->inode, this, &value);
+        if (ret == -1) {
+                gf_log (this->name, GF_LOG_DEBUG, "context not set in inode "
+                        "(%p)", loc->inode);
+                op_errno = EINVAL;
+                goto unwind;
+        }
+
+        inode_ctx = (sp_inode_ctx_t *)(long) value;
+        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, inode_ctx, unwind, op_errno,
+                                        EINVAL);
+
+        LOCK (&inode_ctx->lock);
+        {
+                op_ret = inode_ctx->op_ret;
+                op_errno = inode_ctx->op_errno;
+        }
+        UNLOCK (&inode_ctx->lock);
+
+        if ((op_ret == -1) && (op_errno != ENOENT)) {
+                goto unwind;
+        }
+
+        STACK_WIND (frame, sp_create_cbk, FIRST_CHILD(this),
+                    FIRST_CHILD(this)->fops->create, loc, flags, mode, fd);
+
+        return 0;
+
+unwind:
+        SP_STACK_UNWIND (frame, -1, op_errno, NULL);
+        return 0;
+}
+
+
+int32_t
 sp_create (call_frame_t *frame,	xlator_t *this,	loc_t *loc, int32_t flags,
            mode_t mode, fd_t *fd)
 {
-        sp_local_t *local     = NULL;
-        int32_t     ret       = -1;
-        int32_t     op_errno  = -1;
+        sp_local_t     *local        = NULL;
+        int32_t         op_errno     = -1, ret = -1;
+        call_stub_t    *stub         = NULL;
+        char            can_wind     = 0, need_lookup = 0, need_unwind = 1;
 
-        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc, unwind, op_errno,
+        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc, out, op_errno,
                                         EINVAL);
-        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->parent, unwind,
+        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->parent, out,
                                         op_errno, EINVAL);
-        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->path, unwind, op_errno,
+        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->path, out, op_errno,
                                         EINVAL);
-        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->name, unwind, op_errno,
+        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->name, out, op_errno,
                                         EINVAL);
-        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->inode, unwind,
+        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, loc->inode, out,
                                         op_errno, EINVAL);
 
         ret = sp_cache_remove_parent_entry (frame, this, (char *)loc->path);
         if (ret == -1) {
                 op_errno = errno;
                 gf_log (this->name, GF_LOG_ERROR, "%s", strerror (op_errno));
-                goto unwind;
+                goto out;
         }
 
-        local = CALLOC (1, sizeof (*local));
-        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, local, unwind, op_errno,
-                                        ENOMEM);
+        stub = fop_create_stub (frame, sp_create_helper, loc, flags, mode, fd);
+        if (stub == NULL) {
+                op_errno = ENOMEM;
+                gf_log (this->name, GF_LOG_ERROR, "out of memory");
+                goto out;
+        }
 
-        frame->local = local;
+        sp_process_inode_ctx (frame, this, loc, stub, &need_unwind,
+                              &need_lookup, &can_wind, &op_errno);
 
-        ret = loc_copy (&local->loc, loc);
-        if (ret == -1) {
-                op_errno = errno;
-                gf_log (this->name, GF_LOG_ERROR, "%s", strerror (op_errno));
-                goto unwind;
-        }
+out:
+        if (need_unwind) {
+                SP_STACK_UNWIND (frame, -1, op_errno, NULL);
+        } else if (need_lookup) {
+                STACK_WIND (frame, sp_lookup_cbk, FIRST_CHILD(this),
+                            FIRST_CHILD(this)->fops->lookup, loc, NULL);
+        } else if (can_wind) {
+                if (frame->local == NULL) {
+                        need_unwind = 1;
 
-	STACK_WIND (frame, sp_create_cbk, FIRST_CHILD(this),
-                    FIRST_CHILD(this)->fops->create, loc, flags, mode, fd);
+                        local = CALLOC (1, sizeof (*local));
+                        GF_VALIDATE_OR_GOTO_WITH_ERROR (this->name, local,
+                                                        out, op_errno,
+                                                        ENOMEM);
 
-        return 0;
+                        frame->local = local;
 
-unwind:
-        SP_STACK_UNWIND (frame, -1, op_errno, fd);
+                        ret = loc_copy (&local->loc, loc);
+                        if (ret == -1) {
+                                op_errno = errno;
+                                gf_log (this->name, GF_LOG_ERROR, "%s",
+                                        strerror (op_errno));
+                                goto out;
+                        }
+                }
+
+                STACK_WIND (frame, sp_create_cbk, FIRST_CHILD(this),
+                            FIRST_CHILD(this)->fops->create, loc, flags,
+                            mode, fd);
+        }
+        
         return 0;
 }