Merge branch 'linus' into core/softlockup

Conflicts:

	kernel/softlockup.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 12 insertions, 319 deletions

diff --git a/fs/gfs2/locking/dlm/thread.c b/fs/gfs2/locking/dlm/thread.c
index e53db6fd28a..38823efd698 100644
--- a/fs/gfs2/locking/dlm/thread.c
+++ b/fs/gfs2/locking/dlm/thread.c
@@ -9,367 +9,60 @@
 
 #include "lock_dlm.h"
 
-/* A lock placed on this queue is re-submitted to DLM as soon as the lock_dlm
-   thread gets to it. */
-
-static void queue_submit(struct gdlm_lock *lp)
-{
-	struct gdlm_ls *ls = lp->ls;
-
-	spin_lock(&ls->async_lock);
-	list_add_tail(&lp->delay_list, &ls->submit);
-	spin_unlock(&ls->async_lock);
-	wake_up(&ls->thread_wait);
-}
-
-static void process_blocking(struct gdlm_lock *lp, int bast_mode)
-{
-	struct gdlm_ls *ls = lp->ls;
-	unsigned int cb = 0;
-
-	switch (gdlm_make_lmstate(bast_mode)) {
-	case LM_ST_EXCLUSIVE:
-		cb = LM_CB_NEED_E;
-		break;
-	case LM_ST_DEFERRED:
-		cb = LM_CB_NEED_D;
-		break;
-	case LM_ST_SHARED:
-		cb = LM_CB_NEED_S;
-		break;
-	default:
-		gdlm_assert(0, "unknown bast mode %u", lp->bast_mode);
-	}
-
-	ls->fscb(ls->sdp, cb, &lp->lockname);
-}
-
-static void wake_up_ast(struct gdlm_lock *lp)
-{
-	clear_bit(LFL_AST_WAIT, &lp->flags);
-	smp_mb__after_clear_bit();
-	wake_up_bit(&lp->flags, LFL_AST_WAIT);
-}
-
-static void process_complete(struct gdlm_lock *lp)
-{
-	struct gdlm_ls *ls = lp->ls;
-	struct lm_async_cb acb;
-	s16 prev_mode = lp->cur;
-
-	memset(&acb, 0, sizeof(acb));
-
-	if (lp->lksb.sb_status == -DLM_ECANCEL) {
-		log_info("complete dlm cancel %x,%llx flags %lx",
-		 	 lp->lockname.ln_type,
-			 (unsigned long long)lp->lockname.ln_number,
-			 lp->flags);
-
-		lp->req = lp->cur;
-		acb.lc_ret |= LM_OUT_CANCELED;
-		if (lp->cur == DLM_LOCK_IV)
-			lp->lksb.sb_lkid = 0;
-		goto out;
-	}
-
-	if (test_and_clear_bit(LFL_DLM_UNLOCK, &lp->flags)) {
-		if (lp->lksb.sb_status != -DLM_EUNLOCK) {
-			log_info("unlock sb_status %d %x,%llx flags %lx",
-				 lp->lksb.sb_status, lp->lockname.ln_type,
-				 (unsigned long long)lp->lockname.ln_number,
-				 lp->flags);
-			return;
-		}
-
-		lp->cur = DLM_LOCK_IV;
-		lp->req = DLM_LOCK_IV;
-		lp->lksb.sb_lkid = 0;
-
-		if (test_and_clear_bit(LFL_UNLOCK_DELETE, &lp->flags)) {
-			gdlm_delete_lp(lp);
-			return;
-		}
-		goto out;
-	}
-
-	if (lp->lksb.sb_flags & DLM_SBF_VALNOTVALID)
-		memset(lp->lksb.sb_lvbptr, 0, GDLM_LVB_SIZE);
-
-	if (lp->lksb.sb_flags & DLM_SBF_ALTMODE) {
-		if (lp->req == DLM_LOCK_PR)
-			lp->req = DLM_LOCK_CW;
-		else if (lp->req == DLM_LOCK_CW)
-			lp->req = DLM_LOCK_PR;
-	}
-
-	/*
-	 * A canceled lock request.  The lock was just taken off the delayed
-	 * list and was never even submitted to dlm.
-	 */
-
-	if (test_and_clear_bit(LFL_CANCEL, &lp->flags)) {
-		log_info("complete internal cancel %x,%llx",
-		 	 lp->lockname.ln_type,
-			 (unsigned long long)lp->lockname.ln_number);
-		lp->req = lp->cur;
-		acb.lc_ret |= LM_OUT_CANCELED;
-		goto out;
-	}
-
-	/*
-	 * An error occured.
-	 */
-
-	if (lp->lksb.sb_status) {
-		/* a "normal" error */
-		if ((lp->lksb.sb_status == -EAGAIN) &&
-		    (lp->lkf & DLM_LKF_NOQUEUE)) {
-			lp->req = lp->cur;
-			if (lp->cur == DLM_LOCK_IV)
-				lp->lksb.sb_lkid = 0;
-			goto out;
-		}
-
-		/* this could only happen with cancels I think */
-		log_info("ast sb_status %d %x,%llx flags %lx",
-			 lp->lksb.sb_status, lp->lockname.ln_type,
-			 (unsigned long long)lp->lockname.ln_number,
-			 lp->flags);
-		if (lp->lksb.sb_status == -EDEADLOCK &&
-		    lp->ls->fsflags & LM_MFLAG_CONV_NODROP) {
-			lp->req = lp->cur;
-			acb.lc_ret |= LM_OUT_CONV_DEADLK;
-			if (lp->cur == DLM_LOCK_IV)
-				lp->lksb.sb_lkid = 0;
-			goto out;
-		} else
-			return;
-	}
-
-	/*
-	 * This is an AST for an EX->EX conversion for sync_lvb from GFS.
-	 */
-
-	if (test_and_clear_bit(LFL_SYNC_LVB, &lp->flags)) {
-		wake_up_ast(lp);
-		return;
-	}
-
-	/*
-	 * A lock has been demoted to NL because it initially completed during
-	 * BLOCK_LOCKS.  Now it must be requested in the originally requested
-	 * mode.
-	 */
-
-	if (test_and_clear_bit(LFL_REREQUEST, &lp->flags)) {
-		gdlm_assert(lp->req == DLM_LOCK_NL, "%x,%llx",
-			    lp->lockname.ln_type,
-			    (unsigned long long)lp->lockname.ln_number);
-		gdlm_assert(lp->prev_req > DLM_LOCK_NL, "%x,%llx",
-			    lp->lockname.ln_type,
-			    (unsigned long long)lp->lockname.ln_number);
-
-		lp->cur = DLM_LOCK_NL;
-		lp->req = lp->prev_req;
-		lp->prev_req = DLM_LOCK_IV;
-		lp->lkf &= ~DLM_LKF_CONVDEADLK;
-
-		set_bit(LFL_NOCACHE, &lp->flags);
-
-		if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) &&
-		    !test_bit(LFL_NOBLOCK, &lp->flags))
-			gdlm_queue_delayed(lp);
-		else
-			queue_submit(lp);
-		return;
-	}
-
-	/*
-	 * A request is granted during dlm recovery.  It may be granted
-	 * because the locks of a failed node were cleared.  In that case,
-	 * there may be inconsistent data beneath this lock and we must wait
-	 * for recovery to complete to use it.  When gfs recovery is done this
-	 * granted lock will be converted to NL and then reacquired in this
-	 * granted state.
-	 */
-
-	if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) &&
-	    !test_bit(LFL_NOBLOCK, &lp->flags) &&
-	    lp->req != DLM_LOCK_NL) {
-
-		lp->cur = lp->req;
-		lp->prev_req = lp->req;
-		lp->req = DLM_LOCK_NL;
-		lp->lkf |= DLM_LKF_CONVERT;
-		lp->lkf &= ~DLM_LKF_CONVDEADLK;
-
-		log_debug("rereq %x,%llx id %x %d,%d",
-			  lp->lockname.ln_type,
-			  (unsigned long long)lp->lockname.ln_number,
-			  lp->lksb.sb_lkid, lp->cur, lp->req);
-
-		set_bit(LFL_REREQUEST, &lp->flags);
-		queue_submit(lp);
-		return;
-	}
-
-	/*
-	 * DLM demoted the lock to NL before it was granted so GFS must be
-	 * told it cannot cache data for this lock.
-	 */
-
-	if (lp->lksb.sb_flags & DLM_SBF_DEMOTED)
-		set_bit(LFL_NOCACHE, &lp->flags);
-
-out:
-	/*
-	 * This is an internal lock_dlm lock
-	 */
-
-	if (test_bit(LFL_INLOCK, &lp->flags)) {
-		clear_bit(LFL_NOBLOCK, &lp->flags);
-		lp->cur = lp->req;
-		wake_up_ast(lp);
-		return;
-	}
-
-	/*
-	 * Normal completion of a lock request.  Tell GFS it now has the lock.
-	 */
-
-	clear_bit(LFL_NOBLOCK, &lp->flags);
-	lp->cur = lp->req;
-
-	acb.lc_name = lp->lockname;
-	acb.lc_ret |= gdlm_make_lmstate(lp->cur);
-
-	if (!test_and_clear_bit(LFL_NOCACHE, &lp->flags) &&
-	    (lp->cur > DLM_LOCK_NL) && (prev_mode > DLM_LOCK_NL))
-		acb.lc_ret |= LM_OUT_CACHEABLE;
-
-	ls->fscb(ls->sdp, LM_CB_ASYNC, &acb);
-}
-
-static inline int no_work(struct gdlm_ls *ls, int blocking)
+static inline int no_work(struct gdlm_ls *ls)
 {
 	int ret;
 
 	spin_lock(&ls->async_lock);
-	ret = list_empty(&ls->complete) && list_empty(&ls->submit);
-	if (ret && blocking)
-		ret = list_empty(&ls->blocking);
+	ret = list_empty(&ls->submit);
 	spin_unlock(&ls->async_lock);
 
 	return ret;
 }
 
-static inline int check_drop(struct gdlm_ls *ls)
-{
-	if (!ls->drop_locks_count)
-		return 0;
-
-	if (time_after(jiffies, ls->drop_time + ls->drop_locks_period * HZ)) {
-		ls->drop_time = jiffies;
-		if (ls->all_locks_count >= ls->drop_locks_count)
-			return 1;
-	}
-	return 0;
-}
-
-static int gdlm_thread(void *data, int blist)
+static int gdlm_thread(void *data)
 {
 	struct gdlm_ls *ls = (struct gdlm_ls *) data;
 	struct gdlm_lock *lp = NULL;
-	uint8_t complete, blocking, submit, drop;
-
-	/* Only thread1 is allowed to do blocking callbacks since gfs
-	   may wait for a completion callback within a blocking cb. */
 
 	while (!kthread_should_stop()) {
 		wait_event_interruptible(ls->thread_wait,
-				!no_work(ls, blist) || kthread_should_stop());
-
-		complete = blocking = submit = drop = 0;
+				!no_work(ls) || kthread_should_stop());
 
 		spin_lock(&ls->async_lock);
 
-		if (blist && !list_empty(&ls->blocking)) {
-			lp = list_entry(ls->blocking.next, struct gdlm_lock,
-					blist);
-			list_del_init(&lp->blist);
-			blocking = lp->bast_mode;
-			lp->bast_mode = 0;
-		} else if (!list_empty(&ls->complete)) {
-			lp = list_entry(ls->complete.next, struct gdlm_lock,
-					clist);
-			list_del_init(&lp->clist);
-			complete = 1;
-		} else if (!list_empty(&ls->submit)) {
+		if (!list_empty(&ls->submit)) {
 			lp = list_entry(ls->submit.next, struct gdlm_lock,
 					delay_list);
 			list_del_init(&lp->delay_list);
-			submit = 1;
+			spin_unlock(&ls->async_lock);
+			gdlm_do_lock(lp);
+			spin_lock(&ls->async_lock);
 		}
-
-		drop = check_drop(ls);
 		spin_unlock(&ls->async_lock);
-
-		if (complete)
-			process_complete(lp);
-
-		else if (blocking)
-			process_blocking(lp, blocking);
-
-		else if (submit)
-			gdlm_do_lock(lp);
-
-		if (drop)
-			ls->fscb(ls->sdp, LM_CB_DROPLOCKS, NULL);
-
-		schedule();
 	}
 
 	return 0;
 }
 
-static int gdlm_thread1(void *data)
-{
-	return gdlm_thread(data, 1);
-}
-
-static int gdlm_thread2(void *data)
-{
-	return gdlm_thread(data, 0);
-}
-
 int gdlm_init_threads(struct gdlm_ls *ls)
 {
 	struct task_struct *p;
 	int error;
 
-	p = kthread_run(gdlm_thread1, ls, "lock_dlm1");
-	error = IS_ERR(p);
-	if (error) {
-		log_error("can't start lock_dlm1 thread %d", error);
-		return error;
-	}
-	ls->thread1 = p;
-
-	p = kthread_run(gdlm_thread2, ls, "lock_dlm2");
+	p = kthread_run(gdlm_thread, ls, "lock_dlm");
 	error = IS_ERR(p);
 	if (error) {
-		log_error("can't start lock_dlm2 thread %d", error);
-		kthread_stop(ls->thread1);
+		log_error("can't start lock_dlm thread %d", error);
 		return error;
 	}
-	ls->thread2 = p;
+	ls->thread = p;
 
 	return 0;
 }
 
 void gdlm_release_threads(struct gdlm_ls *ls)
 {
-	kthread_stop(ls->thread1);
-	kthread_stop(ls->thread2);
+	kthread_stop(ls->thread);
 }