ext4: pair trace_ext4_writepages & trace_ext4_writepages_result

Pair the two trace events to make troubeshooting writepages
easier, and it should be more convinient to write a simple script
to parse the traces.

Cc: linux-ext4@vger.kernel.org
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 94aac67b55c96b8ac5cf3ba982875361f4917beb..43015fa69c3a2f804ee06c83aec59f5112f7cdcf 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2423,16 +2423,15 @@ static int ext4_writepages(struct address_space *mapping,
         * because that could violate lock ordering on umount
         */
        if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
-               return 0;
+               goto out_writepages;
 
        if (ext4_should_journal_data(inode)) {
                struct blk_plug plug;
-               int ret;
 
                blk_start_plug(&plug);
                ret = write_cache_pages(mapping, wbc, __writepage, mapping);
                blk_finish_plug(&plug);
-               return ret;
+               goto out_writepages;
        }
 
        /*
@@ -2445,8 +2444,10 @@ static int ext4_writepages(struct address_space *mapping,
         * *never* be called, so if that ever happens, we would want
         * the stack trace.
         */
-       if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED))
-               return -EROFS;
+       if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED)) {
+               ret = -EROFS;
+               goto out_writepages;
+       }
 
        if (ext4_should_dioread_nolock(inode)) {
                /*