Bob Peterson wrote:
Part of the problem was that inodes were being recycled
before their buffers were flushed to the journal logs.
Set aside "after this patch, the problem goes away" thing ...
I haven't checked previous three patches yet so I may not have the
overall picture ... but why adding the journal flush spin lock here
could prevent the new inode to get re-used before its associated buffer
are flushed to the logs ? Could you elaborate more ?
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index b93ac45..2d7f7ea 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -865,12 +865,15 @@ static struct inode *try_rgrp_unlink(struct gfs2_rgrpd
*rgd, u64 *last_unlinked)
struct inode *inode;
u32 goal = 0, block;
u64 no_addr;
+ struct gfs2_sbd *sdp = rgd->rd_sbd;
for(;;) {
if (goal >= rgd->rd_data)
break;
+ down_write(&sdp->sd_log_flush_lock);
block = rgblk_search(rgd, goal, GFS2_BLKST_UNLINKED,
GFS2_BLKST_UNLINKED);
+ up_write(&sdp->sd_log_flush_lock);
if (block == BFITNOENT)
break;
My concern is that GFS2's usage of sd_log_flush_lock has been very
abused lately. The journal logic is gradually becoming difficult to
understand and maintain. With this change, we move a local spin lock
(that belongs to log.c) into another sub-component (rgrp). Intuitively,
this is not right.
-- Wendy
