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-rw-r--r--fs/gfs2/glock.c233
-rw-r--r--fs/gfs2/glock.h2
-rw-r--r--fs/gfs2/incore.h8
-rw-r--r--fs/gfs2/main.c1
-rw-r--r--fs/gfs2/ops_super.c28
5 files changed, 93 insertions, 179 deletions
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index a3a24f2e99d2..e7075945b051 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -54,7 +54,7 @@ struct glock_iter {
typedef void (*glock_examiner) (struct gfs2_glock * gl);
static int gfs2_dump_lockstate(struct gfs2_sbd *sdp);
-static void gfs2_glock_xmote_th(struct gfs2_holder *gh);
+static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh);
static void gfs2_glock_drop_th(struct gfs2_glock *gl);
static DECLARE_RWSEM(gfs2_umount_flush_sem);
static struct dentry *gfs2_root;
@@ -212,7 +212,6 @@ int gfs2_glock_put(struct gfs2_glock *gl)
gfs2_assert(sdp, list_empty(&gl->gl_reclaim));
gfs2_assert(sdp, list_empty(&gl->gl_holders));
gfs2_assert(sdp, list_empty(&gl->gl_waiters1));
- gfs2_assert(sdp, list_empty(&gl->gl_waiters2));
gfs2_assert(sdp, list_empty(&gl->gl_waiters3));
glock_free(gl);
rv = 1;
@@ -399,7 +398,7 @@ void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *
{
gh->gh_state = state;
gh->gh_flags = flags;
- gh->gh_iflags &= 1 << HIF_ALLOCED;
+ gh->gh_iflags = 0;
gh->gh_ip = (unsigned long)__builtin_return_address(0);
}
@@ -416,54 +415,8 @@ void gfs2_holder_uninit(struct gfs2_holder *gh)
gh->gh_ip = 0;
}
-/**
- * gfs2_holder_get - get a struct gfs2_holder structure
- * @gl: the glock
- * @state: the state we're requesting
- * @flags: the modifier flags
- * @gfp_flags:
- *
- * Figure out how big an impact this function has. Either:
- * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd
- * 2) Leave it like it is
- *
- * Returns: the holder structure, NULL on ENOMEM
- */
-
-static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl,
- unsigned int state,
- int flags, gfp_t gfp_flags)
-{
- struct gfs2_holder *gh;
-
- gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags);
- if (!gh)
- return NULL;
-
- gfs2_holder_init(gl, state, flags, gh);
- set_bit(HIF_ALLOCED, &gh->gh_iflags);
- gh->gh_ip = (unsigned long)__builtin_return_address(0);
- return gh;
-}
-
-/**
- * gfs2_holder_put - get rid of a struct gfs2_holder structure
- * @gh: the holder structure
- *
- */
-
-static void gfs2_holder_put(struct gfs2_holder *gh)
-{
- gfs2_holder_uninit(gh);
- kfree(gh);
-}
-
-static void gfs2_holder_dispose_or_wake(struct gfs2_holder *gh)
+static void gfs2_holder_wake(struct gfs2_holder *gh)
{
- if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) {
- gfs2_holder_put(gh);
- return;
- }
clear_bit(HIF_WAIT, &gh->gh_iflags);
smp_mb();
wake_up_bit(&gh->gh_iflags, HIF_WAIT);
@@ -529,7 +482,7 @@ static int rq_promote(struct gfs2_holder *gh)
gfs2_reclaim_glock(sdp);
}
- gfs2_glock_xmote_th(gh);
+ gfs2_glock_xmote_th(gh->gh_gl, gh);
spin_lock(&gl->gl_spin);
}
return 1;
@@ -552,7 +505,7 @@ static int rq_promote(struct gfs2_holder *gh)
gh->gh_error = 0;
set_bit(HIF_HOLDER, &gh->gh_iflags);
- gfs2_holder_dispose_or_wake(gh);
+ gfs2_holder_wake(gh);
return 0;
}
@@ -564,32 +517,24 @@ static int rq_promote(struct gfs2_holder *gh)
* Returns: 1 if the queue is blocked
*/
-static int rq_demote(struct gfs2_holder *gh)
+static int rq_demote(struct gfs2_glock *gl)
{
- struct gfs2_glock *gl = gh->gh_gl;
-
if (!list_empty(&gl->gl_holders))
return 1;
- if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) {
- list_del_init(&gh->gh_list);
- gh->gh_error = 0;
- spin_unlock(&gl->gl_spin);
- gfs2_holder_dispose_or_wake(gh);
- spin_lock(&gl->gl_spin);
- } else {
- gl->gl_req_gh = gh;
- set_bit(GLF_LOCK, &gl->gl_flags);
- spin_unlock(&gl->gl_spin);
-
- if (gh->gh_state == LM_ST_UNLOCKED ||
- gl->gl_state != LM_ST_EXCLUSIVE)
- gfs2_glock_drop_th(gl);
- else
- gfs2_glock_xmote_th(gh);
-
- spin_lock(&gl->gl_spin);
+ if (gl->gl_state == gl->gl_demote_state ||
+ gl->gl_state == LM_ST_UNLOCKED) {
+ clear_bit(GLF_DEMOTE, &gl->gl_flags);
+ return 0;
}
+ set_bit(GLF_LOCK, &gl->gl_flags);
+ spin_unlock(&gl->gl_spin);
+ if (gl->gl_demote_state == LM_ST_UNLOCKED ||
+ gl->gl_state != LM_ST_EXCLUSIVE)
+ gfs2_glock_drop_th(gl);
+ else
+ gfs2_glock_xmote_th(gl, NULL);
+ spin_lock(&gl->gl_spin);
return 0;
}
@@ -617,16 +562,8 @@ static void run_queue(struct gfs2_glock *gl)
else
gfs2_assert_warn(gl->gl_sbd, 0);
- } else if (!list_empty(&gl->gl_waiters2) &&
- !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) {
- gh = list_entry(gl->gl_waiters2.next,
- struct gfs2_holder, gh_list);
-
- if (test_bit(HIF_DEMOTE, &gh->gh_iflags))
- blocked = rq_demote(gh);
- else
- gfs2_assert_warn(gl->gl_sbd, 0);
-
+ } else if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
+ blocked = rq_demote(gl);
} else if (!list_empty(&gl->gl_waiters3)) {
gh = list_entry(gl->gl_waiters3.next,
struct gfs2_holder, gh_list);
@@ -717,50 +654,24 @@ static void gfs2_glmutex_unlock(struct gfs2_glock *gl)
}
/**
- * handle_callback - add a demote request to a lock's queue
+ * handle_callback - process a demote request
* @gl: the glock
* @state: the state the caller wants us to change to
*
- * Note: This may fail sliently if we are out of memory.
+ * There are only two requests that we are going to see in actual
+ * practise: LM_ST_SHARED and LM_ST_UNLOCKED
*/
static void handle_callback(struct gfs2_glock *gl, unsigned int state)
{
- struct gfs2_holder *gh, *new_gh = NULL;
-
-restart:
spin_lock(&gl->gl_spin);
-
- list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
- if (test_bit(HIF_DEMOTE, &gh->gh_iflags) &&
- gl->gl_req_gh != gh) {
- if (gh->gh_state != state)
- gh->gh_state = LM_ST_UNLOCKED;
- goto out;
- }
- }
-
- if (new_gh) {
- list_add_tail(&new_gh->gh_list, &gl->gl_waiters2);
- new_gh = NULL;
- } else {
- spin_unlock(&gl->gl_spin);
-
- new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_NOFS);
- if (!new_gh)
- return;
- set_bit(HIF_DEMOTE, &new_gh->gh_iflags);
- set_bit(HIF_DEALLOC, &new_gh->gh_iflags);
- set_bit(HIF_WAIT, &new_gh->gh_iflags);
-
- goto restart;
+ if (test_and_set_bit(GLF_DEMOTE, &gl->gl_flags) == 0) {
+ gl->gl_demote_state = state;
+ gl->gl_demote_time = jiffies;
+ } else if (gl->gl_demote_state != LM_ST_UNLOCKED) {
+ gl->gl_demote_state = state;
}
-
-out:
spin_unlock(&gl->gl_spin);
-
- if (new_gh)
- gfs2_holder_put(new_gh);
}
/**
@@ -820,56 +731,37 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret)
/* Deal with each possible exit condition */
- if (!gh)
+ if (!gh) {
gl->gl_stamp = jiffies;
- else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
+ if (ret & LM_OUT_CANCELED)
+ op_done = 0;
+ else
+ clear_bit(GLF_DEMOTE, &gl->gl_flags);
+ } else {
spin_lock(&gl->gl_spin);
list_del_init(&gh->gh_list);
gh->gh_error = -EIO;
- spin_unlock(&gl->gl_spin);
- } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) {
- spin_lock(&gl->gl_spin);
- list_del_init(&gh->gh_list);
- if (gl->gl_state == gh->gh_state ||
- gl->gl_state == LM_ST_UNLOCKED) {
+ if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+ goto out;
+ gh->gh_error = GLR_CANCELED;
+ if (ret & LM_OUT_CANCELED)
+ goto out;
+ if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
+ list_add_tail(&gh->gh_list, &gl->gl_holders);
gh->gh_error = 0;
- } else {
- if (gfs2_assert_warn(sdp, gh->gh_flags &
- (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1)
- fs_warn(sdp, "ret = 0x%.8X\n", ret);
- gh->gh_error = GLR_TRYFAILED;
+ set_bit(HIF_HOLDER, &gh->gh_iflags);
+ set_bit(HIF_FIRST, &gh->gh_iflags);
+ op_done = 0;
+ goto out;
}
- spin_unlock(&gl->gl_spin);
-
- if (ret & LM_OUT_CANCELED)
- handle_callback(gl, LM_ST_UNLOCKED);
-
- } else if (ret & LM_OUT_CANCELED) {
- spin_lock(&gl->gl_spin);
- list_del_init(&gh->gh_list);
- gh->gh_error = GLR_CANCELED;
- spin_unlock(&gl->gl_spin);
-
- } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
- spin_lock(&gl->gl_spin);
- list_move_tail(&gh->gh_list, &gl->gl_holders);
- gh->gh_error = 0;
- set_bit(HIF_HOLDER, &gh->gh_iflags);
- spin_unlock(&gl->gl_spin);
-
- set_bit(HIF_FIRST, &gh->gh_iflags);
-
- op_done = 0;
-
- } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
- spin_lock(&gl->gl_spin);
- list_del_init(&gh->gh_list);
gh->gh_error = GLR_TRYFAILED;
- spin_unlock(&gl->gl_spin);
-
- } else {
+ if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
+ goto out;
+ gh->gh_error = -EINVAL;
if (gfs2_assert_withdraw(sdp, 0) == -1)
fs_err(sdp, "ret = 0x%.8X\n", ret);
+out:
+ spin_unlock(&gl->gl_spin);
}
if (glops->go_xmote_bh)
@@ -887,7 +779,7 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret)
gfs2_glock_put(gl);
if (gh)
- gfs2_holder_dispose_or_wake(gh);
+ gfs2_holder_wake(gh);
}
/**
@@ -898,12 +790,11 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret)
*
*/
-void gfs2_glock_xmote_th(struct gfs2_holder *gh)
+void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh)
{
- struct gfs2_glock *gl = gh->gh_gl;
struct gfs2_sbd *sdp = gl->gl_sbd;
- int flags = gh->gh_flags;
- unsigned state = gh->gh_state;
+ int flags = gh ? gh->gh_flags : 0;
+ unsigned state = gh ? gh->gh_state : gl->gl_demote_state;
const struct gfs2_glock_operations *glops = gl->gl_ops;
int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB |
LM_FLAG_NOEXP | LM_FLAG_ANY |
@@ -953,6 +844,7 @@ static void drop_bh(struct gfs2_glock *gl, unsigned int ret)
gfs2_assert_warn(sdp, !ret);
state_change(gl, LM_ST_UNLOCKED);
+ clear_bit(GLF_DEMOTE, &gl->gl_flags);
if (glops->go_inval)
glops->go_inval(gl, DIO_METADATA);
@@ -974,7 +866,7 @@ static void drop_bh(struct gfs2_glock *gl, unsigned int ret)
gfs2_glock_put(gl);
if (gh)
- gfs2_holder_dispose_or_wake(gh);
+ gfs2_holder_wake(gh);
}
/**
@@ -1291,9 +1183,8 @@ void gfs2_glock_dq(struct gfs2_holder *gh)
if (glops->go_unlock)
glops->go_unlock(gh);
- gl->gl_stamp = jiffies;
-
spin_lock(&gl->gl_spin);
+ gl->gl_stamp = jiffies;
}
clear_bit(GLF_LOCK, &gl->gl_flags);
@@ -1981,16 +1872,16 @@ static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl)
if (error)
goto out;
}
- list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
- error = dump_holder(gi, "Waiter2", gh);
- if (error)
- goto out;
- }
list_for_each_entry(gh, &gl->gl_waiters3, gh_list) {
error = dump_holder(gi, "Waiter3", gh);
if (error)
goto out;
}
+ if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
+ print_dbg(gi, " Demotion req to state %u (%llu uS ago)\n",
+ gl->gl_demote_state,
+ (u64)(jiffies - gl->gl_demote_time)*1000000/HZ);
+ }
if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) {
if (!test_bit(GLF_LOCK, &gl->gl_flags) &&
list_empty(&gl->gl_holders)) {
diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h
index d7cef7408728..5e662eadc6f2 100644
--- a/fs/gfs2/glock.h
+++ b/fs/gfs2/glock.h
@@ -67,7 +67,7 @@ static inline int gfs2_glock_is_blocking(struct gfs2_glock *gl)
{
int ret;
spin_lock(&gl->gl_spin);
- ret = !list_empty(&gl->gl_waiters2) || !list_empty(&gl->gl_waiters3);
+ ret = test_bit(GLF_DEMOTE, &gl->gl_flags) || !list_empty(&gl->gl_waiters3);
spin_unlock(&gl->gl_spin);
return ret;
}
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 7555261d911f..9c125823d760 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -115,11 +115,8 @@ enum {
/* Actions */
HIF_MUTEX = 0,
HIF_PROMOTE = 1,
- HIF_DEMOTE = 2,
/* States */
- HIF_ALLOCED = 4,
- HIF_DEALLOC = 5,
HIF_HOLDER = 6,
HIF_FIRST = 7,
HIF_ABORTED = 9,
@@ -142,8 +139,8 @@ struct gfs2_holder {
enum {
GLF_LOCK = 1,
GLF_STICKY = 2,
+ GLF_DEMOTE = 3,
GLF_DIRTY = 5,
- GLF_SKIP_WAITERS2 = 6,
};
struct gfs2_glock {
@@ -156,11 +153,12 @@ struct gfs2_glock {
unsigned int gl_state;
unsigned int gl_hash;
+ unsigned int gl_demote_state; /* state requested by remote node */
+ unsigned long gl_demote_time; /* time of first demote request */
struct task_struct *gl_owner;
unsigned long gl_ip;
struct list_head gl_holders;
struct list_head gl_waiters1; /* HIF_MUTEX */
- struct list_head gl_waiters2; /* HIF_DEMOTE */
struct list_head gl_waiters3; /* HIF_PROMOTE */
const struct gfs2_glock_operations *gl_ops;
diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index 218395371dbe..c4bb374eaf92 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -45,7 +45,6 @@ static void gfs2_init_glock_once(void *foo, struct kmem_cache *cachep, unsigned
spin_lock_init(&gl->gl_spin);
INIT_LIST_HEAD(&gl->gl_holders);
INIT_LIST_HEAD(&gl->gl_waiters1);
- INIT_LIST_HEAD(&gl->gl_waiters2);
INIT_LIST_HEAD(&gl->gl_waiters3);
gl->gl_lvb = NULL;
atomic_set(&gl->gl_lvb_count, 0);
diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
index b89999d3a767..485ce3d49923 100644
--- a/fs/gfs2/ops_super.c
+++ b/fs/gfs2/ops_super.c
@@ -284,6 +284,31 @@ static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
}
/**
+ * gfs2_drop_inode - Drop an inode (test for remote unlink)
+ * @inode: The inode to drop
+ *
+ * If we've received a callback on an iopen lock then its because a
+ * remote node tried to deallocate the inode but failed due to this node
+ * still having the inode open. Here we mark the link count zero
+ * since we know that it must have reached zero if the GLF_DEMOTE flag
+ * is set on the iopen glock. If we didn't do a disk read since the
+ * remote node removed the final link then we might otherwise miss
+ * this event. This check ensures that this node will deallocate the
+ * inode's blocks, or alternatively pass the baton on to another
+ * node for later deallocation.
+ */
+static void gfs2_drop_inode(struct inode *inode)
+{
+ if (inode->i_private && inode->i_nlink) {
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
+ if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
+ clear_nlink(inode);
+ }
+ generic_drop_inode(inode);
+}
+
+/**
* gfs2_clear_inode - Deallocate an inode when VFS is done with it
* @inode: The VFS inode
*
@@ -441,7 +466,7 @@ out_unlock:
out_uninit:
gfs2_holder_uninit(&ip->i_iopen_gh);
gfs2_glock_dq_uninit(&gh);
- if (error)
+ if (error && error != GLR_TRYFAILED)
fs_warn(sdp, "gfs2_delete_inode: %d\n", error);
out:
truncate_inode_pages(&inode->i_data, 0);
@@ -481,6 +506,7 @@ const struct super_operations gfs2_super_ops = {
.statfs = gfs2_statfs,
.remount_fs = gfs2_remount_fs,
.clear_inode = gfs2_clear_inode,
+ .drop_inode = gfs2_drop_inode,
.show_options = gfs2_show_options,
};