[GFS2] Use atomic_t for journal free blocks counter

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 (file)
--- 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 (file)
--- 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 (file)
--- 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) {