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path: root/fs/gfs2/locking/dlm/thread.c
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Diffstat (limited to 'fs/gfs2/locking/dlm/thread.c')
-rw-r--r--fs/gfs2/locking/dlm/thread.c331
1 files changed, 12 insertions, 319 deletions
diff --git a/fs/gfs2/locking/dlm/thread.c b/fs/gfs2/locking/dlm/thread.c
index e53db6f..38823ef 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);
}
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