LU-9210 statahead: missing barrier before wake_up

[fs/lustre-release.git] / lustre / llite / statahead.c

diff --git a/lustre/llite/statahead.c b/lustre/llite/statahead.c
index 8b63dc2..c11c682 100644 (file)
--- a/lustre/llite/statahead.c
+++ b/lustre/llite/statahead.c
@@ -23,7 +23,7 @@
  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2011, 2015, Intel Corporation.
+ * Copyright (c) 2011, 2016, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -179,8 +179,8 @@ static inline int is_omitted_entry(struct ll_statahead_info *sai, __u64 index)
 
 /* allocate sa_entry and hash it to allow scanner process to find it */
 static struct sa_entry *
-sa_alloc(struct ll_statahead_info *sai, __u64 index, const char *name, int len,
-        const struct lu_fid *fid)
+sa_alloc(struct dentry *parent, struct ll_statahead_info *sai, __u64 index,
+        const char *name, int len, const struct lu_fid *fid)
 {
        struct ll_inode_info *lli;
        struct sa_entry *entry;
@@ -203,7 +203,7 @@ sa_alloc(struct ll_statahead_info *sai, __u64 index, const char *name, int len,
        dname = (char *)entry + sizeof(struct sa_entry);
        memcpy(dname, name, len);
        dname[len] = 0;
-       entry->se_qstr.hash = full_name_hash(name, len);
+       entry->se_qstr.hash = ll_full_name_hash(parent, name, len);
        entry->se_qstr.len = len;
        entry->se_qstr.name = dname;
        entry->se_fid = *fid;
@@ -506,6 +506,18 @@ static void ll_agl_trigger(struct inode *inode, struct ll_statahead_info *sai)
                 RETURN_EXIT;
         }
 
+       /* In case of restore, the MDT has the right size and has already
+        * sent it back without granting the layout lock, inode is up-to-date.
+        * Then AGL (async glimpse lock) is useless.
+        * Also to glimpse we need the layout, in case of a runninh restore
+        * the MDT holds the layout lock so the glimpse will block up to the
+        * end of restore (statahead/agl will block) */
+       if (ll_file_test_flag(lli, LLIF_FILE_RESTORING)) {
+               lli->lli_agl_index = 0;
+               iput(inode);
+               RETURN_EXIT;
+       }
+
         /* Someone is in glimpse (sync or async), do nothing. */
        rc = down_write_trylock(&lli->lli_glimpse_sem);
         if (rc == 0) {
@@ -701,6 +713,8 @@ static int ll_statahead_interpret(struct ptlrpc_request *req,
                list_add_tail(&entry->se_list, &sai->sai_interim_entries);
        }
        sai->sai_replied++;
+
+       smp_mb();
        if (waitq != NULL)
                wake_up(waitq);
        spin_unlock(&lli->lli_sa_lock);
@@ -834,7 +848,7 @@ static void sa_statahead(struct dentry *parent, const char *name, int len,
        int rc;
        ENTRY;
 
-       entry = sa_alloc(sai, sai->sai_index, name, len, fid);
+       entry = sa_alloc(parent, sai, sai->sai_index, name, len, fid);
        if (IS_ERR(entry))
                RETURN_EXIT;
 
@@ -990,8 +1004,6 @@ static int ll_statahead_thread(void *arg)
        if (IS_ERR(op_data))
                GOTO(out, rc = PTR_ERR(op_data));
 
-       op_data->op_max_pages = ll_i2sbi(dir)->ll_md_brw_pages;
-
        if (sbi->ll_flags & LL_SBI_AGL_ENABLED)
                ll_start_agl(parent, sai);
 
@@ -1233,8 +1245,12 @@ void ll_deauthorize_statahead(struct inode *dir, void *key)
                /*
                 * statahead thread may not quit yet because it needs to cache
                 * entries, now it's time to tell it to quit.
+                *
+                * In case sai is released, wake_up() is called inside spinlock,
+                * so we have to call smp_mb() explicitely to serialize ops.
                 */
                thread_set_flags(&sai->sai_thread, SVC_STOPPING);
+               smp_mb();
                wake_up(&sai->sai_thread.t_ctl_waitq);
        }
        spin_unlock(&lli->lli_sa_lock);
@@ -1274,7 +1290,6 @@ static int is_first_dirent(struct inode *dir, struct dentry *dentry)
        /**
         *FIXME choose the start offset of the readdir
         */
-       op_data->op_max_pages = ll_i2sbi(dir)->ll_md_brw_pages;
 
        ll_dir_chain_init(&chain);
        page = ll_get_dir_page(dir, op_data, 0, &chain);