[PATCH 20/58] [GFS2] Use atomic_t for journal free blocks counter

swhiteho
2008-01-21T10:09:24Z

From: Steven Whitehouse <swhiteho@redhat.com>

This patch changes the counter which keeps track of the free
blocks in the journal to an atomic_t in preparation for the
following patch which will update the log reservation code.

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

diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 911822d..7ae0206 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -595,7 +595,7 @@ struct gfs2_sbd {
struct list_head sd_log_le_databuf;
struct list_head sd_log_le_ordered;

- unsigned int sd_log_blks_free;
+ atomic_t sd_log_blks_free;
struct mutex sd_log_reserve_mutex;

u64 sd_log_sequence;
diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index d246843..9192398 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -301,7 +301,7 @@ int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)

mutex_lock(&sdp->sd_log_reserve_mutex);
gfs2_log_lock(sdp);
- while(sdp->sd_log_blks_free <= (blks + reserved_blks)) {
+ while(atomic_read(&sdp->sd_log_blks_free) <= (blks + reserved_blks)) {
gfs2_log_unlock(sdp);
gfs2_ail1_empty(sdp, 0);
gfs2_log_flush(sdp, NULL);
@@ -310,7 +310,7 @@ int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
gfs2_ail1_start(sdp, 0);
gfs2_log_lock(sdp);
}
- sdp->sd_log_blks_free -= blks;
+ atomic_sub(blks, &sdp->sd_log_blks_free);
gfs2_log_unlock(sdp);
mutex_unlock(&sdp->sd_log_reserve_mutex);

@@ -330,9 +330,9 @@ void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
{

gfs2_log_lock(sdp);
- sdp->sd_log_blks_free += blks;
+ atomic_add(blks, &sdp->sd_log_blks_free);
gfs2_assert_withdraw(sdp,
- sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
+ atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks);
gfs2_log_unlock(sdp);
up_read(&sdp->sd_log_flush_lock);
}
@@ -559,8 +559,8 @@ static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
ail2_empty(sdp, new_tail);

gfs2_log_lock(sdp);
- sdp->sd_log_blks_free += dist;
- gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
+ atomic_add(dist, &sdp->sd_log_blks_free);
+ gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks);
gfs2_log_unlock(sdp);

sdp->sd_log_tail = new_tail;
@@ -733,7 +733,7 @@ void __gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
log_flush_commit(sdp);
else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
gfs2_log_lock(sdp);
- sdp->sd_log_blks_free--; /* Adjust for unreserved buffer */
+ atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
gfs2_log_unlock(sdp);
log_write_header(sdp, 0, PULL);
}
@@ -773,12 +773,12 @@ static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
reserved = calc_reserved(sdp);
- old = sdp->sd_log_blks_free;
- sdp->sd_log_blks_free += tr->tr_reserved -
- (reserved - sdp->sd_log_blks_reserved);
+ old = atomic_read(&sdp->sd_log_blks_free);
+ atomic_add(tr->tr_reserved - (reserved - sdp->sd_log_blks_reserved),
+ &sdp->sd_log_blks_free);

- gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old);
- gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <=
+ gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) >= old);
+ gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
sdp->sd_jdesc->jd_blocks);

sdp->sd_log_blks_reserved = reserved;
@@ -831,7 +831,7 @@ void gfs2_log_shutdown(struct gfs2_sbd *sdp)
log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT,
(sdp->sd_log_tail == current_tail(sdp)) ? 0 : PULL);

- gfs2_assert_warn(sdp, sdp->sd_log_blks_free == sdp->sd_jdesc->jd_blocks);
+ gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));

diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 52aaba9..1bba6ac 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -339,7 +339,7 @@ static int init_journal(struct gfs2_sbd *sdp, int undo)

if (sdp->sd_args.ar_spectator) {
sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
- sdp->sd_log_blks_free = sdp->sd_jdesc->jd_blocks;
+ atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
} else {
if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
fs_err(sdp, "can't mount journal #%u\n",
@@ -376,7 +376,7 @@ static int init_journal(struct gfs2_sbd *sdp, int undo)
sdp->sd_jdesc->jd_jid, error);
goto fail_jinode_gh;
}
- sdp->sd_log_blks_free = sdp->sd_jdesc->jd_blocks;
+ atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
}

if (sdp->sd_lockstruct.ls_first) {
--
1.5.1.2