The previous patch added a new GL_ST_UNLOCK state that simply
cleared the GLF_LOCK bit, then went into the RUN state. Since the
RUN state immediately sets the GLF_LOCK again and does a few other
things, we can optimize it by putting GL_ST_UNLOCK in the middle
of the GL_ST_RUN state. This avoids unlock-then-lock and extra
checks and skips directly to the resulting promotion/demotion state.
Signed-off-by: Bob Peterson <rpete...@redhat.com>
---
fs/gfs2/glock.c | 6 ++----
fs/gfs2/glock.h | 2 +-
2 files changed, 3 insertions(+), 5 deletions(-)
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 33f4a530caf4..29e6d9a440ec 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -724,7 +724,9 @@ static void __state_machine(struct gfs2_glock *gl, int
new_state,
GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS,
&gl->gl_flags));
+ /* Fall through */
+ case GL_ST_UNLOCK:
if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
gl->gl_demote_state != gl->gl_state)
gl->gl_mch = nonblock ? GL_ST_DEMOTE_NONBLOCK :
@@ -751,10 +753,6 @@ 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);
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h
index 5bbf3118c7c3..e1a5bc2d3f76 100644
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -131,7 +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 */
+ GL_ST_UNLOCK = 9, /* Unlock the glock */
};
struct lm_lockops {
--
2.19.1
