Commit ab0d7566 authored by Bob Peterson's avatar Bob Peterson Committed by Steven Whitehouse
Browse files

[GFS2] Eliminate gl_req_bh 



This patch further reduces the memory needs of GFS2 by
eliminating the gl_req_bh variable from struct gfs2_glock.

Signed-off-by: default avatarBob Peterson <rpeterso@redhat.com>
Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
parent 110acf38

fs/gfs2/glock.c

+51 −56
Original line number Diff line number Diff line
@@ -338,7 +338,6 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, 
	gl->gl_ip = 0;

	gl->gl_ops = glops;

	gl->gl_req_gh = NULL;

	gl->gl_req_bh = NULL;

	gl->gl_vn = 0;

	gl->gl_stamp = jiffies;

	gl->gl_tchange = jiffies;
@@ -743,6 +742,50 @@ static void state_change(struct gfs2_glock *gl, unsigned int new_state) 
	gl->gl_tchange = jiffies;

}



/**

 * drop_bh - Called after a lock module unlock completes

 * @gl: the glock

 * @ret: the return status

 *

 * Doesn't wake up the process waiting on the struct gfs2_holder (if any)

 * Doesn't drop the reference on the glock the top half took out

 *

 */



static void drop_bh(struct gfs2_glock *gl, unsigned int ret)

{

	struct gfs2_sbd *sdp = gl->gl_sbd;

	const struct gfs2_glock_operations *glops = gl->gl_ops;

	struct gfs2_holder *gh = gl->gl_req_gh;



	gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));

	gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));

	gfs2_assert_warn(sdp, !ret);



	state_change(gl, LM_ST_UNLOCKED);



	if (glops->go_inval)

		glops->go_inval(gl, DIO_METADATA);



	if (gh) {

		spin_lock(&gl->gl_spin);

		list_del_init(&gh->gh_list);

		gh->gh_error = 0;

		spin_unlock(&gl->gl_spin);

	}



	spin_lock(&gl->gl_spin);

	gfs2_demote_wake(gl);

	gl->gl_req_gh = NULL;

	clear_bit(GLF_LOCK, &gl->gl_flags);

	spin_unlock(&gl->gl_spin);



	gfs2_glock_put(gl);



	if (gh)

		gfs2_holder_wake(gh);

}



/**

 * xmote_bh - Called after the lock module is done acquiring a lock

 * @gl: The glock in question
@@ -758,6 +801,11 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) 
	int prev_state = gl->gl_state;

	int op_done = 1;



	if ((ret & LM_OUT_ST_MASK) == LM_ST_UNLOCKED) {

		drop_bh(gl, ret);

		return;

	}



	gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));

	gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));

	gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC));
@@ -783,7 +831,6 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) 
		} else {

			spin_lock(&gl->gl_spin);

			if (gl->gl_state != gl->gl_demote_state) {

				gl->gl_req_bh = NULL;

				spin_unlock(&gl->gl_spin);

				gfs2_glock_drop_th(gl);

				gfs2_glock_put(gl);
@@ -825,7 +872,6 @@ out: 
	if (op_done) {

		spin_lock(&gl->gl_spin);

		gl->gl_req_gh = NULL;

		gl->gl_req_bh = NULL;

		clear_bit(GLF_LOCK, &gl->gl_flags);

		spin_unlock(&gl->gl_spin);

	}
@@ -864,7 +910,6 @@ static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh) 
	gfs2_assert_warn(sdp, state != gl->gl_state);



	gfs2_glock_hold(gl);

	gl->gl_req_bh = xmote_bh;



	lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags);
@@ -877,51 +922,6 @@ static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh) 
		xmote_bh(gl, lck_ret);

}



/**

 * drop_bh - Called after a lock module unlock completes

 * @gl: the glock

 * @ret: the return status

 *

 * Doesn't wake up the process waiting on the struct gfs2_holder (if any)

 * Doesn't drop the reference on the glock the top half took out

 *

 */



static void drop_bh(struct gfs2_glock *gl, unsigned int ret)

{

	struct gfs2_sbd *sdp = gl->gl_sbd;

	const struct gfs2_glock_operations *glops = gl->gl_ops;

	struct gfs2_holder *gh = gl->gl_req_gh;



	gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));

	gfs2_assert_warn(sdp, list_empty(&gl->gl_holders));

	gfs2_assert_warn(sdp, !ret);



	state_change(gl, LM_ST_UNLOCKED);



	if (glops->go_inval)

		glops->go_inval(gl, DIO_METADATA);



	if (gh) {

		spin_lock(&gl->gl_spin);

		list_del_init(&gh->gh_list);

		gh->gh_error = 0;

		spin_unlock(&gl->gl_spin);

	}



	spin_lock(&gl->gl_spin);

	gfs2_demote_wake(gl);

	gl->gl_req_gh = NULL;

	gl->gl_req_bh = NULL;

	clear_bit(GLF_LOCK, &gl->gl_flags);

	spin_unlock(&gl->gl_spin);



	gfs2_glock_put(gl);



	if (gh)

		gfs2_holder_wake(gh);

}



/**

 * gfs2_glock_drop_th - call into the lock module to unlock a lock

 * @gl: the glock
@@ -942,7 +942,6 @@ static void gfs2_glock_drop_th(struct gfs2_glock *gl) 
	gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED);



	gfs2_glock_hold(gl);

	gl->gl_req_bh = drop_bh;



	ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state);
@@ -971,8 +970,7 @@ static void do_cancels(struct gfs2_holder *gh) 
	while (gl->gl_req_gh != gh &&

	       !test_bit(HIF_HOLDER, &gh->gh_iflags) &&

	       !list_empty(&gh->gh_list)) {

		if (gl->gl_req_bh && !(gl->gl_req_gh &&

				     (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) {

		if (!(gl->gl_req_gh && (gl->gl_req_gh->gh_flags & GL_NOCANCEL))) {

			spin_unlock(&gl->gl_spin);

			gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock);

			msleep(100);
@@ -1042,7 +1040,6 @@ static int glock_wait_internal(struct gfs2_holder *gh) 


		spin_lock(&gl->gl_spin);

		gl->gl_req_gh = NULL;

		gl->gl_req_bh = NULL;

		clear_bit(GLF_LOCK, &gl->gl_flags);

		run_queue(gl);

		spin_unlock(&gl->gl_spin);
@@ -1535,8 +1532,7 @@ void gfs2_glock_cb(void *cb_data, unsigned int type, void *data) 
		gl = gfs2_glock_find(sdp, &async->lc_name);

		if (gfs2_assert_warn(sdp, gl))

			return;

		if (!gfs2_assert_warn(sdp, gl->gl_req_bh))

			gl->gl_req_bh(gl, async->lc_ret);

		xmote_bh(gl, async->lc_ret);

		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)

			gfs2_glock_put(gl);

		up_read(&gfs2_umount_flush_sem);
@@ -1898,7 +1894,6 @@ static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl) 
		print_dbg(gi, "  gl_owner = -1\n");

	print_dbg(gi, "  gl_ip = %lu\n", gl->gl_ip);

	print_dbg(gi, "  req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no");

	print_dbg(gi, "  req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no");

	print_dbg(gi, "  lvb_count = %d\n", atomic_read(&gl->gl_lvb_count));

	print_dbg(gi, "  object = %s\n", (gl->gl_object) ? "yes" : "no");

	print_dbg(gi, "  reclaim = %s\n",

fs/gfs2/incore.h

+0 −1
Original line number Diff line number Diff line
@@ -191,7 +191,6 @@ struct gfs2_glock { 
	const struct gfs2_glock_operations *gl_ops;



	struct gfs2_holder *gl_req_gh;

	gfs2_glop_bh_t gl_req_bh;



	void *gl_lock;

	char *gl_lvb;

CRA Git | Maintained and supported by SUSTech CRA and CCSE