Re: [Ext2-devel] [PATCH] concurrent block allocation for ext2 against 2.5.64

[Andreas Dilger]

On Mar 13, 2003  11:55 +0300, Alex Tomas wrote:
> as Andrew said, concurrent balloc for ext3 is useless because of BKL.
> and I saw it in benchmarks. but it may be useful for ext2.

Sadly, we are constantly diverging the ext2/ext3 codebases.  Lots of
features are going into ext3, but lots of fixes/improvements are only
going into ext2.  Is ext3 holding BKL for doing journal_start() still?

Looking at ext3_prepare_write() we grab the BKL for doing journal_start()
and for journal_stop(), but I don't _think_ we need BKL for journal_stop()
do we?  We may or may not need it for the journal_data case, but that is
not even working right now I think.

It also seems we are getting BKL in ext3_truncate(), which likely isn't
needed past journal_start(), although we do need to have superblock-only
lock for ext3_orphan_add/del.

Cheers, Andreas
--
Andreas Dilger
http://sourceforge.net/projects/ext2resize/
http://www-mddsp.enel.ucalgary.ca/People/adilger/