[DLM] canceling deadlocked lock

Add a function that can be used through libdlm by a system daemon to cancel
another process's deadlocked lock.  A completion ast with EDEADLK is returned
to the process waiting for the lock.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This commit is contained in:
David Teigland
2007-05-29 08:46:00 -05:00
committed by Steven Whitehouse
parent 84d8cd69a8
commit 8b4021fa43
5 changed files with 81 additions and 0 deletions

View File

@@ -300,6 +300,11 @@ static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
rv = -ETIMEDOUT;
}
if (rv == -DLM_ECANCEL && (lkb->lkb_flags & DLM_IFL_DEADLOCK_CANCEL)) {
lkb->lkb_flags &= ~DLM_IFL_DEADLOCK_CANCEL;
rv = -EDEADLK;
}
lkb->lkb_lksb->sb_status = rv;
lkb->lkb_lksb->sb_flags = lkb->lkb_sbflags;
@@ -4450,6 +4455,54 @@ int dlm_user_cancel(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
return error;
}
int dlm_user_deadlock(struct dlm_ls *ls, uint32_t flags, uint32_t lkid)
{
struct dlm_lkb *lkb;
struct dlm_args args;
struct dlm_user_args *ua;
struct dlm_rsb *r;
int error;
dlm_lock_recovery(ls);
error = find_lkb(ls, lkid, &lkb);
if (error)
goto out;
ua = (struct dlm_user_args *)lkb->lkb_astparam;
error = set_unlock_args(flags, ua, &args);
if (error)
goto out_put;
/* same as cancel_lock(), but set DEADLOCK_CANCEL after lock_rsb */
r = lkb->lkb_resource;
hold_rsb(r);
lock_rsb(r);
error = validate_unlock_args(lkb, &args);
if (error)
goto out_r;
lkb->lkb_flags |= DLM_IFL_DEADLOCK_CANCEL;
error = _cancel_lock(r, lkb);
out_r:
unlock_rsb(r);
put_rsb(r);
if (error == -DLM_ECANCEL)
error = 0;
/* from validate_unlock_args() */
if (error == -EBUSY)
error = 0;
out_put:
dlm_put_lkb(lkb);
out:
dlm_unlock_recovery(ls);
return error;
}
/* lkb's that are removed from the waiters list by revert are just left on the
orphans list with the granted orphan locks, to be freed by purge */