[PATCH 06/51] [GFS2] Move some code inside the log lock

swhiteho
2007-10-04T09:19:30Z

From: Bob Peterson <rpeterso@redhat.com>

This is the first of five patches for bug #248176:

There were still some critical variables being manipulated outside
the log_lock spinlock. That usually resulted in a hang.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 3b395c4..a0371f8 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -117,7 +117,7 @@ static void buf_lo_before_commit(struct gfs2_sbd *sdp)
struct buffer_head *bh;
struct gfs2_log_descriptor *ld;
struct gfs2_bufdata *bd1 = NULL, *bd2;
- unsigned int total = sdp->sd_log_num_buf;
+ unsigned int total;
unsigned int offset = BUF_OFFSET;
unsigned int limit;
unsigned int num;
@@ -127,12 +127,16 @@ static void buf_lo_before_commit(struct gfs2_sbd *sdp)
limit = buf_limit(sdp);
/* for 4k blocks, limit = 503 */

+ gfs2_log_lock(sdp);
+ total = sdp->sd_log_num_buf;
bd1 = bd2 = list_prepare_entry(bd1, &sdp->sd_log_le_buf, bd_le.le_list);
while(total) {
num = total;
if (total > limit)
num = limit;
+ gfs2_log_unlock(sdp);
bh = gfs2_log_get_buf(sdp);
+ gfs2_log_lock(sdp);
ld = (struct gfs2_log_descriptor *)bh->b_data;
ptr = (__be64 *)(bh->b_data + offset);
ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
@@ -152,21 +156,27 @@ static void buf_lo_before_commit(struct gfs2_sbd *sdp)
break;
}

+ gfs2_log_unlock(sdp);
set_buffer_dirty(bh);
ll_rw_block(WRITE, 1, &bh);
+ gfs2_log_lock(sdp);

n = 0;
list_for_each_entry_continue(bd2, &sdp->sd_log_le_buf,
bd_le.le_list) {
+ gfs2_log_unlock(sdp);
bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
set_buffer_dirty(bh);
ll_rw_block(WRITE, 1, &bh);
+ gfs2_log_lock(sdp);
if (++n >= num)
break;
}

+ BUG_ON(total < num);
total -= num;
}
+ gfs2_log_unlock(sdp);
}

static void buf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
@@ -524,7 +534,7 @@ static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
struct gfs2_log_descriptor *ld;
unsigned int limit;
unsigned int total_dbuf;
- unsigned int total_jdata = sdp->sd_log_num_jdata;
+ unsigned int total_jdata;
unsigned int num, n;
__be64 *ptr = NULL;

@@ -536,6 +546,7 @@ static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
*/
gfs2_log_lock(sdp);
total_dbuf = sdp->sd_log_num_databuf;
+ total_jdata = sdp->sd_log_num_jdata;
bd2 = bd1 = list_prepare_entry(bd1, &sdp->sd_log_le_databuf,
bd_le.le_list);
while(total_dbuf) {
@@ -621,10 +632,10 @@ static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
}
gfs2_log_unlock(sdp);
if (bh) {
- set_buffer_mapped(bh);
set_buffer_dirty(bh);
ll_rw_block(WRITE, 1, &bh);
bh = NULL;
+ ptr = NULL;
}
n = 0;
gfs2_log_lock(sdp);
--
1.5.1.2