gfs2: Clean up on-stack transactions

Replace the TR_ALLOCED flag by its inverse, TR_ONSTACK: that way, the flag only
needs to be set in the exceptional case of on-stack transactions.  Split off
__gfs2_trans_begin from gfs2_trans_begin and use it to replace the open-coded
version in gfs2_ail_empty_gl.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index fd1f52f..a067924 100644 (file)
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -86,16 +86,12 @@ static int gfs2_ail_empty_gl(struct gfs2_glock *gl)
 {
        struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
        struct gfs2_trans tr;
+       unsigned int revokes;
        int ret;
 
-       memset(&tr, 0, sizeof(tr));
-       INIT_LIST_HEAD(&tr.tr_buf);
-       INIT_LIST_HEAD(&tr.tr_databuf);
-       INIT_LIST_HEAD(&tr.tr_ail1_list);
-       INIT_LIST_HEAD(&tr.tr_ail2_list);
-       tr.tr_revokes = atomic_read(&gl->gl_ail_count);
+       revokes = atomic_read(&gl->gl_ail_count);
 
-       if (!tr.tr_revokes) {
+       if (!revokes) {
                bool have_revokes;
                bool log_in_flight;
 
@@ -122,23 +118,14 @@ static int gfs2_ail_empty_gl(struct gfs2_glock *gl)
                return 0;
        }
 
-       /* A shortened, inline version of gfs2_trans_begin()
-         * tr->alloced is not set since the transaction structure is
-         * on the stack */
-       tr.tr_reserved = 1 + gfs2_struct2blk(sdp, tr.tr_revokes);
-       tr.tr_ip = _RET_IP_;
-       sb_start_intwrite(sdp->sd_vfs);
-       ret = gfs2_log_reserve(sdp, tr.tr_reserved);
-       if (ret < 0) {
-               sb_end_intwrite(sdp->sd_vfs);
-               return ret;
-       }
-       WARN_ON_ONCE(current->journal_info);
-       current->journal_info = &tr;
-
-       __gfs2_ail_flush(gl, 0, tr.tr_revokes);
-
+       memset(&tr, 0, sizeof(tr));
+       set_bit(TR_ONSTACK, &tr.tr_flags);
+       ret = __gfs2_trans_begin(&tr, sdp, 0, revokes, _RET_IP_);
+       if (ret)
+               goto flush;
+       __gfs2_ail_flush(gl, 0, revokes);
        gfs2_trans_end(sdp);
+
 flush:
        gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
                       GFS2_LFC_AIL_EMPTY_GL);

diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 8e1ab8e..c3f6dd3 100644 (file)
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -490,7 +490,7 @@ struct gfs2_quota_data {
 enum {
        TR_TOUCHED = 1,
        TR_ATTACHED = 2,
-       TR_ALLOCED = 3,
+       TR_ONSTACK = 3,
 };
 
 struct gfs2_trans {

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index e4dc23a..0fceb60 100644 (file)
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -1114,7 +1114,7 @@ static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
        if (sdp->sd_log_tr) {
                gfs2_merge_trans(sdp, tr);
        } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
-               gfs2_assert_withdraw(sdp, test_bit(TR_ALLOCED, &tr->tr_flags));
+               gfs2_assert_withdraw(sdp, !test_bit(TR_ONSTACK, &tr->tr_flags));
                sdp->sd_log_tr = tr;
                set_bit(TR_ATTACHED, &tr->tr_flags);
        }

diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c
index ae040b5..db29ca2 100644 (file)
--- a/fs/gfs2/trans.c
+++ b/fs/gfs2/trans.c
@@ -37,10 +37,10 @@ static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr)
                tr->tr_num_revoke, tr->tr_num_revoke_rm);
 }
 
-int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
-                    unsigned int revokes)
+int __gfs2_trans_begin(struct gfs2_trans *tr, struct gfs2_sbd *sdp,
+                      unsigned int blocks, unsigned int revokes,
+                      unsigned long ip)
 {
-       struct gfs2_trans *tr;
        int error;
 
        if (current->journal_info) {
@@ -52,15 +52,10 @@ int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
        if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
                return -EROFS;
 
-       tr = kmem_cache_zalloc(gfs2_trans_cachep, GFP_NOFS);
-       if (!tr)
-               return -ENOMEM;
-
-       tr->tr_ip = _RET_IP_;
+       tr->tr_ip = ip;
        tr->tr_blocks = blocks;
        tr->tr_revokes = revokes;
        tr->tr_reserved = 1;
-       set_bit(TR_ALLOCED, &tr->tr_flags);
        if (blocks)
                tr->tr_reserved += 6 + blocks;
        if (revokes)
@@ -74,17 +69,28 @@ int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
        sb_start_intwrite(sdp->sd_vfs);
 
        error = gfs2_log_reserve(sdp, tr->tr_reserved);
-       if (error)
-               goto fail;
+       if (error) {
+               sb_end_intwrite(sdp->sd_vfs);
+               return error;
+       }
 
        current->journal_info = tr;
 
        return 0;
+}
 
-fail:
-       sb_end_intwrite(sdp->sd_vfs);
-       kmem_cache_free(gfs2_trans_cachep, tr);
+int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
+                    unsigned int revokes)
+{
+       struct gfs2_trans *tr;
+       int error;
 
+       tr = kmem_cache_zalloc(gfs2_trans_cachep, GFP_NOFS);
+       if (!tr)
+               return -ENOMEM;
+       error = __gfs2_trans_begin(tr, sdp, blocks, revokes, _RET_IP_);
+       if (error)
+               kmem_cache_free(gfs2_trans_cachep, tr);
        return error;
 }
 
@@ -92,13 +98,12 @@ void gfs2_trans_end(struct gfs2_sbd *sdp)
 {
        struct gfs2_trans *tr = current->journal_info;
        s64 nbuf;
-       int alloced = test_bit(TR_ALLOCED, &tr->tr_flags);
 
        current->journal_info = NULL;
 
        if (!test_bit(TR_TOUCHED, &tr->tr_flags)) {
                gfs2_log_release(sdp, tr->tr_reserved);
-               if (alloced)
+               if (!test_bit(TR_ONSTACK, &tr->tr_flags))
                        gfs2_trans_free(sdp, tr);
                sb_end_intwrite(sdp->sd_vfs);
                return;
@@ -113,7 +118,8 @@ void gfs2_trans_end(struct gfs2_sbd *sdp)
                gfs2_print_trans(sdp, tr);
 
        gfs2_log_commit(sdp, tr);
-       if (alloced && !test_bit(TR_ATTACHED, &tr->tr_flags))
+       if (!test_bit(TR_ONSTACK, &tr->tr_flags) &&
+           !test_bit(TR_ATTACHED, &tr->tr_flags))
                gfs2_trans_free(sdp, tr);
        up_read(&sdp->sd_log_flush_lock);
 

diff --git a/fs/gfs2/trans.h b/fs/gfs2/trans.h
index 83199ce..55f2530 100644 (file)
--- a/fs/gfs2/trans.h
+++ b/fs/gfs2/trans.h
@@ -34,6 +34,9 @@ static inline unsigned int gfs2_rg_blocks(const struct gfs2_inode *ip, unsigned
        return rgd->rd_length;
 }
 
+extern int __gfs2_trans_begin(struct gfs2_trans *tr, struct gfs2_sbd *sdp,
+                             unsigned int blocks, unsigned int revokes,
+                             unsigned long ip);
 extern int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
                            unsigned int revokes);