[GFS2] Remove local exclusive glock mode

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

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 (i.e. LM_ST_EXCLUSIVE is always locally exclusive as well
as globally exclusive).

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

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 8e4b55a2bd773dc1c59175697501ee52166f9ac3..1345c3d44ede133ff9bf9f940ad949844b15fb7d 100644 (file)
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -391,10 +391,6 @@ void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
        gh->gh_flags = flags;
        gh->gh_error = 0;
        gh->gh_iflags = 0;
-
-       if (gh->gh_state == LM_ST_EXCLUSIVE)
-               gh->gh_flags |= GL_LOCAL_EXCL;
-
        gfs2_glock_hold(gl);
 }
 
@@ -412,9 +408,6 @@ void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *
 {
        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);
 }
@@ -557,11 +550,11 @@ static int rq_promote(struct gfs2_holder *gh)
                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;
        }
 
@@ -1363,10 +1356,7 @@ static int glock_compare(const void *arg_a, const void *arg_b)
                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 ddc56dc4ec9fe59d4902d323e8458d253edb7073..1eaeacdd14a44a66448beb717863e0b35fbed6b2 100644 (file)
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -20,7 +20,6 @@
 #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 e4da26fe406fa05feaf7e71563c71aa6464a3489..dda68586f7575f6b8309ef7a8658d89d4680e936 100644 (file)
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -295,7 +295,7 @@ static int inode_go_lock(struct gfs2_holder *gh)
 
        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 fbf55063928fbc40cd32e6073c663c8581aeb000..4855e8cca62269e01b1c5e70433771747c64b95c 100644 (file)
--- a/fs/gfs2/ops_export.c
+++ b/fs/gfs2/ops_export.c
@@ -216,8 +216,7 @@ static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_obj)
        }
 
        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 ce5353ac8f3dfdde8ff402371ae9780f72e8e3d7..70f424fcf1cdb8468c825367aead70c48a462254 100644 (file)
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -354,8 +354,7 @@ int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
        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;
 
@@ -524,8 +523,7 @@ 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;
 
@@ -578,9 +576,8 @@ 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;