[Cluster-devel] cluster/gfs-kernel/src/gfs inode.h ops_export.c

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

Here is a proposed patch for GFS2 to remove the local exclusive flag. In
the other places it was used, mutex's are always held earlier in the
call path, so it appears redundant.

Also, the GFS2 holders were setting local exclusive in any case where
the requested lock was LM_ST_EXCLUSIVE. So the other places in the glock
code where the flag was tested have been replaced with tests for the
lock state being LM_ST_EXCLUSIVE in order to ensure the logic is the
same as before.

Steve.


diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 4381469..14577fd 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -396,10 +396,6 @@ void gfs2_holder_init(struct gfs2_glock 
 	gh->gh_error = 0;
 	gh->gh_iflags = 0;
 	init_completion(&gh->gh_wait);
-
-	if (gh->gh_state == LM_ST_EXCLUSIVE)
-		gh->gh_flags |= GL_LOCAL_EXCL;
-
 	gfs2_glock_hold(gl);
 }
 
@@ -417,9 +413,6 @@ void gfs2_holder_reinit(unsigned int sta
 {
 	gh->gh_state = state;
 	gh->gh_flags = flags;
-	if (gh->gh_state == LM_ST_EXCLUSIVE)
-		gh->gh_flags |= GL_LOCAL_EXCL;
-
 	gh->gh_iflags &= 1 << HIF_ALLOCED;
 	gh->gh_ip = (unsigned long)__builtin_return_address(0);
 }
@@ -537,11 +530,11 @@ static int rq_promote(struct gfs2_holder
 		set_bit(GLF_LOCK, &gl->gl_flags);
 	} else {
 		struct gfs2_holder *next_gh;
-		if (gh->gh_flags & GL_LOCAL_EXCL)
+		if (gh->gh_state == LM_ST_EXCLUSIVE)
 			return 1;
 		next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder,
 				     gh_list);
-		if (next_gh->gh_flags & GL_LOCAL_EXCL)
+		if (next_gh->gh_state == LM_ST_EXCLUSIVE)
 			 return 1;
 	}
 
@@ -1470,10 +1463,7 @@ static int glock_compare(const void *arg
 		return 1;
 	if (a->ln_number < b->ln_number)
 		return -1;
-	if (gh_a->gh_state == LM_ST_SHARED && gh_b->gh_state == LM_ST_EXCLUSIVE)
-		return 1;
-	if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && (gh_b->gh_flags & GL_LOCAL_EXCL))
-		return 1;
+	BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type);
 	return 0;
 }
 
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h
index fb39108..bdcbfbd 100644
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -20,7 +20,6 @@ #define LM_FLAG_NOEXP		0x00000004
 #define LM_FLAG_ANY		0x00000008
 #define LM_FLAG_PRIORITY	0x00000010 */
 
-#define GL_LOCAL_EXCL		0x00000020
 #define GL_ASYNC		0x00000040
 #define GL_EXACT		0x00000080
 #define GL_SKIP			0x00000100
diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index b068d10..094adda 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -295,7 +295,7 @@ static int inode_go_lock(struct gfs2_hol
 
 	if ((ip->i_di.di_flags & GFS2_DIF_TRUNC_IN_PROG) &&
 	    (gl->gl_state == LM_ST_EXCLUSIVE) &&
-	    (gh->gh_flags & GL_LOCAL_EXCL))
+	    (gh->gh_state == LM_ST_EXCLUSIVE))
 		error = gfs2_truncatei_resume(ip);
 
 	return error;
diff --git a/fs/gfs2/ops_export.c b/fs/gfs2/ops_export.c
index 6ea979c..0453cbe 100644
--- a/fs/gfs2/ops_export.c
+++ b/fs/gfs2/ops_export.c
@@ -217,8 +217,7 @@ static struct dentry *gfs2_get_dentry(st
 	}
 
 	error = gfs2_glock_nq_num(sdp, inum->no_addr, &gfs2_inode_glops,
-				  LM_ST_SHARED, LM_FLAG_ANY | GL_LOCAL_EXCL,
-				  &i_gh);
+				  LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
 	if (error)
 		return ERR_PTR(error);
 
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 43a24f2..6b5b138 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -359,8 +359,7 @@ int gfs2_jindex_hold(struct gfs2_sbd *sd
 	mutex_lock(&sdp->sd_jindex_mutex);
 
 	for (;;) {
-		error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
-					   GL_LOCAL_EXCL, ji_gh);
+		error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
 		if (error)
 			break;
 
@@ -529,8 +528,7 @@ int gfs2_make_fs_rw(struct gfs2_sbd *sdp
 	struct gfs2_log_header_host head;
 	int error;
 
-	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
-				   GL_LOCAL_EXCL, &t_gh);
+	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
 	if (error)
 		return error;
 
@@ -583,9 +581,8 @@ int gfs2_make_fs_ro(struct gfs2_sbd *sdp
 	gfs2_quota_sync(sdp);
 	gfs2_statfs_sync(sdp);
 
-	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
-				GL_LOCAL_EXCL | GL_NOCACHE,
-				&t_gh);
+	error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
+				   &t_gh);
 	if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 		return error;