Before this patch, function run_queue would do special processing
before calling the state machine for the blocking and non-blocking
demote-in-progress cases. This function rolls those functions into
the state machine, which will allow us to eventually simplify with
later patches.
Signed-off-by: Bob Peterson <rpete...@redhat.com>
---
fs/gfs2/glock.c | 44 +++++++++++++++++++++++++++++---------------
fs/gfs2/glock.h | 2 ++
2 files changed, 31 insertions(+), 15 deletions(-)
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 8dc98d069afa..023e2186b374 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -631,21 +631,9 @@ __acquires(&gl->gl_lockref.lock)
if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
gl->gl_demote_state != gl->gl_state) {
- if (find_first_holder(gl)) {
- clear_bit(GLF_LOCK, &gl->gl_flags);
- smp_mb__after_atomic();
- return;
- }
- if (nonblock) {
- clear_bit(GLF_LOCK, &gl->gl_flags);
- smp_mb__after_atomic();
- gl->gl_lockref.count++;
- __gfs2_glock_queue_work(gl, 0);
- return;
- }
- set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
- GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
- gl->gl_target = gl->gl_demote_state;
+ __state_machine(gl, nonblock ? GL_ST_DEMOTE_NONBLOCK :
+ GL_ST_BLOCKING_DEMOTE);
+ return;
} else {
if (test_bit(GLF_DEMOTE, &gl->gl_flags))
gfs2_demote_wake(gl);
@@ -713,6 +701,32 @@ static void __state_machine(struct gfs2_glock *gl, int
new_state)
if (ret == -EAGAIN)
gl->gl_mch = GL_ST_FINISH_XMOTE;
break;
+
+ case GL_ST_BLOCKING_DEMOTE:
+ gl->gl_mch = GL_ST_IDLE;
+ if (find_first_holder(gl)) {
+ clear_bit(GLF_LOCK, &gl->gl_flags);
+ smp_mb__after_atomic();
+ break;
+ }
+ set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
+ GLOCK_BUG_ON(gl, gl->gl_demote_state ==
LM_ST_EXCLUSIVE);
+ gl->gl_target = gl->gl_demote_state;
+ gl->gl_mch = GL_ST_DO_XMOTE;
+ break;
+
+ case GL_ST_DEMOTE_NONBLOCK:
+ gl->gl_mch = GL_ST_IDLE;
+ if (find_first_holder(gl)) {
+ clear_bit(GLF_LOCK, &gl->gl_flags);
+ smp_mb__after_atomic();
+ break;
+ }
+ clear_bit(GLF_LOCK, &gl->gl_flags);
+ smp_mb__after_atomic();
+ gl->gl_lockref.count++;
+ __gfs2_glock_queue_work(gl, 0);
+ break;
}
} while (gl->gl_mch != GL_ST_IDLE);
}
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h
index 8333bbc5a197..c8b704a73638 100644
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -126,6 +126,8 @@ enum gl_machine_states {
GL_ST_DO_XMOTE = 2, /* Promote or demote a waiter */
GL_ST_DO_XMOTE_UNLOCK = 3, /* Promote or demote a waiter after a failed
state change attempt from dlm. */
+ GL_ST_DEMOTE_NONBLOCK = 4, /* Demote is in progress - non-blocking */
+ GL_ST_BLOCKING_DEMOTE = 5, /* Demote is in progress - blocking */
};
struct lm_lockops {
--
2.19.1
