[Cluster-devel] [PATCH 12/13] GFS2: Add new GL_ST_UNLOCK state to reduce calls to the __ version

[Bob Peterson]

Before this patch, the truncate code called __state_machine but
only did the unlock of GLF_UNLOCK. This patch adds a new state
GL_ST_UNLOCK does the same thing, thus allowing it to call the
regular state_machine function. This reduces the calls to the
helper.

Signed-off-by: Bob Peterson <rpeterso at redhat.com>
---
 fs/gfs2/glock.c | 11 ++++++-----
 fs/gfs2/glock.h |  1 +
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 22ddeda90199..33f4a530caf4 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -750,6 +750,11 @@ static void __state_machine(struct gfs2_glock *gl, int new_state,
 			}
 			gl->gl_mch = GL_ST_RUN;
 			break;
+
+		case GL_ST_UNLOCK:
+			clear_bit(GLF_LOCK, &gl->gl_flags);
+			gl->gl_mch = GL_ST_RUN;
+			break;
 		}
 	} while (gl->gl_mch != GL_ST_IDLE || new_state != GL_ST_IDLE);
 
@@ -774,7 +779,6 @@ static void __state_machine(struct gfs2_glock *gl, int new_state,
  * @gl: pointer to the glock we are transitioning
  * @new_state: The new state we need to execute
  *
- * Just like __state_machine but it acquires the gl_lockref lock
  */
 static void state_machine(struct gfs2_glock *gl, int new_state,
 			  const int nonblock)
@@ -1734,10 +1738,7 @@ void gfs2_glock_finish_truncate(struct gfs2_inode *ip)
 	ret = gfs2_truncatei_resume(ip);
 	gfs2_assert_withdraw(gl->gl_name.ln_sbd, ret == 0);
 
-	spin_lock(&gl->gl_lockref.lock);
-	clear_bit(GLF_LOCK, &gl->gl_flags);
-	__state_machine(gl, GL_ST_RUN, 1);
-	spin_unlock(&gl->gl_lockref.lock);
+	state_machine(gl, GL_ST_UNLOCK, 1);
 }
 
 static const char *state2str(unsigned state)
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h
index 0b1dffb92e8a..5bbf3118c7c3 100644
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -131,6 +131,7 @@ enum gl_machine_states {
 	GL_ST_PROMOTE = 6,	   /* Promote the lock */
 	GL_ST_RUN = 7,		/* "Run" or progress the lock */
 	GL_ST_WORK = 8,		/* Perform general glock work */
+	GL_ST_UNLOCK = 9,	/* Unlock then run */
 };
 
 struct lm_lockops {
-- 
2.19.1