2 files changed, 44 insertions, 16 deletions

diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c
index 3cceef4ad2b7..e9580104b6ba 100644
--- a/fs/jffs2/background.c
+++ b/fs/jffs2/background.c
@@ -95,13 +95,17 @@ static int jffs2_garbage_collect_thread(void *_c)
                         spin_unlock(&c->erase_completion_lock);
                         
 
-                /* This thread is purely an optimisation. But if it runs when
-                   other things could be running, it actually makes things a
-                   lot worse. Use yield() and put it at the back of the runqueue
-                   every time. Especially during boot, pulling an inode in
-                   with read_inode() is much preferable to having the GC thread
-                   get there first. */
-                yield();
+                /* Problem - immediately after bootup, the GCD spends a lot
+                 * of time in places like jffs2_kill_fragtree(); so much so
+                 * that userspace processes (like gdm and X) are starved
+                 * despite plenty of cond_resched()s and renicing.  Yield()
+                 * doesn't help, either (presumably because userspace and GCD
+                 * are generally competing for a higher latency resource -
+                 * disk).
+                 * This forces the GCD to slow the hell down.   Pulling an
+                 * inode in with read_inode() is much preferable to having
+                 * the GC thread get there first. */
+                schedule_timeout_interruptible(msecs_to_jiffies(50));
 
                 /* Put_super will send a SIGKILL and then wait on the sem.
                  */
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index 6ca08ad887c0..1fc1e92356ee 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -220,7 +220,7 @@ static int jffs2_add_tn_to_tree(struct jffs2_sb_info *c,
                                 struct jffs2_tmp_dnode_info *tn)
 {
         uint32_t fn_end = tn->fn->ofs + tn->fn->size;
-        struct jffs2_tmp_dnode_info *this;
+        struct jffs2_tmp_dnode_info *this, *ptn;
 
         dbg_readinode("insert fragment %#04x-%#04x, ver %u at %08x\n", tn->fn->ofs, fn_end, tn->version, ref_offset(tn->fn->raw));
 
@@ -251,11 +251,18 @@ static int jffs2_add_tn_to_tree(struct jffs2_sb_info *c,
         if (this) {
                 /* If the node is coincident with another at a lower address,
                    back up until the other node is found. It may be relevant */
-                while (this->overlapped)
-                        this = tn_prev(this);
-
-                /* First node should never be marked overlapped */
-                BUG_ON(!this);
+                while (this->overlapped) {
+                        ptn = tn_prev(this);
+                        if (!ptn) {
+                                /*
+                                 * We killed a node which set the overlapped
+                                 * flags during the scan. Fix it up.
+                                 */
+                                this->overlapped = 0;
+                                break;
+                        }
+                        this = ptn;
+                }
                 dbg_readinode("'this' found %#04x-%#04x (%s)\n", this->fn->ofs, this->fn->ofs + this->fn->size, this->fn ? "data" : "hole");
         }
 
@@ -360,7 +367,17 @@ static int jffs2_add_tn_to_tree(struct jffs2_sb_info *c,
                         }
                         if (!this->overlapped)
                                 break;
-                        this = tn_prev(this);
+
+                        ptn = tn_prev(this);
+                        if (!ptn) {
+                                /*
+                                 * We killed a node which set the overlapped
+                                 * flags during the scan. Fix it up.
+                                 */
+                                this->overlapped = 0;
+                                break;
+                        }
+                        this = ptn;
                 }
         }
 
@@ -456,8 +473,15 @@ static int jffs2_build_inode_fragtree(struct jffs2_sb_info *c,
                 eat_last(&rii->tn_root, &last->rb);
                 ver_insert(&ver_root, last);
 
-                if (unlikely(last->overlapped))
-                        continue;
+                if (unlikely(last->overlapped)) {
+                        if (pen)
+                                continue;
+                        /*
+                         * We killed a node which set the overlapped
+                         * flags during the scan. Fix it up.
+                         */
+                        last->overlapped = 0;
+                }
 
                 /* Now we have a bunch of nodes in reverse version
                    order, in the tree at ver_root. Most of the time,