btrfs-progs: skip mounted fs when deal with umounted ones for fi show

Stalling problems may happen when exec balance & fi show cmds concurrently.

With the following commit:
        commit 915902c500
        btrfs-progs: fix device missing of btrfs fi show with seed devices

The fi show cmd will bother the mounted fs when only umounted fs should
be handled after @btrfs_can_kernel() has finished showing all mounted ones.

We could skip the mounted fs after @btrfs_can_kernel() is done, then tasks
keeps going on mounted fs while fi show continues on umounted ones separately.

Reported-by: Petr Janecek <janecek@ucw.cz>
Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index 70223d8..b1fb402 100644 (file)
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -53,6 +53,15 @@ struct seen_fsid {
 
 static struct seen_fsid *seen_fsid_hash[SEEN_FSID_HASH_SIZE] = {NULL,};
 
+static int is_seen_fsid(u8 *fsid)
+{
+       u8 hash = fsid[0];
+       int slot = hash % SEEN_FSID_HASH_SIZE;
+       struct seen_fsid *seen = seen_fsid_hash[slot];
+
+       return seen ? 1 : 0;
+}
+
 static int add_seen_fsid(u8 *fsid)
 {
        u8 hash = fsid[0];
@@ -766,6 +775,10 @@ static int map_seed_devices(struct list_head *all_uuids,
                        *found = 1;
                }
 
+               /* skip all fs already shown as mounted fs */
+               if (is_seen_fsid(cur_fs->fsid))
+                       continue;
+
                fs_copy = malloc(sizeof(*fs_copy));
                if (!fs_copy) {
                        ret = -ENOMEM;