dlm: fixes for nodir mode

The "nodir" mode (statically assign master nodes instead
of using the resource directory) has always been highly
experimental, and never seriously used.  This commit
fixes a number of problems, making nodir much more usable.

- Major change to recovery: recover all locks and restart
  all in-progress operations after recovery.  In some
  cases it's not possible to know which in-progess locks
  to recover, so recover all.  (Most require recovery
  in nodir mode anyway since rehashing changes most
  master nodes.)

- Change the way nodir mode is enabled, from a command
  line mount arg passed through gfs2, into a sysfs
  file managed by dlm_controld, consistent with the
  other config settings.

- Allow recovering MSTCPY locks on an rsb that has not
  yet been turned into a master copy.

- Ignore RCOM_LOCK and RCOM_LOCK_REPLY recovery messages
  from a previous, aborted recovery cycle.  Base this
  on the local recovery status not being in the state
  where any nodes should be sending LOCK messages for the
  current recovery cycle.

- Hold rsb lock around dlm_purge_mstcpy_locks() because it
  may run concurrently with dlm_recover_master_copy().

- Maintain highbast on process-copy lkb's (in addition to
  the master as is usual), because the lkb can switch
  back and forth between being a master and being a
  process copy as the master node changes in recovery.

- When recovering MSTCPY locks, flag rsb's that have
  non-empty convert or waiting queues for granting
  at the end of recovery.  (Rename flag from LOCKS_PURGED
  to RECOVER_GRANT and similar for the recovery function,
  because it's not only resources with purged locks
  that need grant a grant attempt.)

- Replace a couple of unnecessary assertion panics with
  error messages.

Signed-off-by: David Teigland <teigland@redhat.com>
This commit is contained in:
David Teigland
2012-04-26 15:54:29 -05:00
parent 6d40c4a708
commit 4875647a08
13 changed files with 311 additions and 179 deletions

View File

@@ -339,9 +339,12 @@ static void set_lock_master(struct list_head *queue, int nodeid)
{
struct dlm_lkb *lkb;
list_for_each_entry(lkb, queue, lkb_statequeue)
if (!(lkb->lkb_flags & DLM_IFL_MSTCPY))
list_for_each_entry(lkb, queue, lkb_statequeue) {
if (!(lkb->lkb_flags & DLM_IFL_MSTCPY)) {
lkb->lkb_nodeid = nodeid;
lkb->lkb_remid = 0;
}
}
}
static void set_master_lkbs(struct dlm_rsb *r)
@@ -354,18 +357,16 @@ static void set_master_lkbs(struct dlm_rsb *r)
/*
* Propagate the new master nodeid to locks
* The NEW_MASTER flag tells dlm_recover_locks() which rsb's to consider.
* The NEW_MASTER2 flag tells recover_lvb() and set_locks_purged() which
* The NEW_MASTER2 flag tells recover_lvb() and recover_grant() which
* rsb's to consider.
*/
static void set_new_master(struct dlm_rsb *r, int nodeid)
{
lock_rsb(r);
r->res_nodeid = nodeid;
set_master_lkbs(r);
rsb_set_flag(r, RSB_NEW_MASTER);
rsb_set_flag(r, RSB_NEW_MASTER2);
unlock_rsb(r);
}
/*
@@ -376,9 +377,9 @@ static void set_new_master(struct dlm_rsb *r, int nodeid)
static int recover_master(struct dlm_rsb *r)
{
struct dlm_ls *ls = r->res_ls;
int error, dir_nodeid, ret_nodeid, our_nodeid = dlm_our_nodeid();
dir_nodeid = dlm_dir_nodeid(r);
int error, ret_nodeid;
int our_nodeid = dlm_our_nodeid();
int dir_nodeid = dlm_dir_nodeid(r);
if (dir_nodeid == our_nodeid) {
error = dlm_dir_lookup(ls, our_nodeid, r->res_name,
@@ -388,7 +389,9 @@ static int recover_master(struct dlm_rsb *r)
if (ret_nodeid == our_nodeid)
ret_nodeid = 0;
lock_rsb(r);
set_new_master(r, ret_nodeid);
unlock_rsb(r);
} else {
recover_list_add(r);
error = dlm_send_rcom_lookup(r, dir_nodeid);
@@ -398,24 +401,33 @@ static int recover_master(struct dlm_rsb *r)
}
/*
* When not using a directory, most resource names will hash to a new static
* master nodeid and the resource will need to be remastered.
* All MSTCPY locks are purged and rebuilt, even if the master stayed the same.
* This is necessary because recovery can be started, aborted and restarted,
* causing the master nodeid to briefly change during the aborted recovery, and
* change back to the original value in the second recovery. The MSTCPY locks
* may or may not have been purged during the aborted recovery. Another node
* with an outstanding request in waiters list and a request reply saved in the
* requestqueue, cannot know whether it should ignore the reply and resend the
* request, or accept the reply and complete the request. It must do the
* former if the remote node purged MSTCPY locks, and it must do the later if
* the remote node did not. This is solved by always purging MSTCPY locks, in
* which case, the request reply would always be ignored and the request
* resent.
*/
static int recover_master_static(struct dlm_rsb *r)
{
int master = dlm_dir_nodeid(r);
int dir_nodeid = dlm_dir_nodeid(r);
int new_master = dir_nodeid;
if (master == dlm_our_nodeid())
master = 0;
if (dir_nodeid == dlm_our_nodeid())
new_master = 0;
if (r->res_nodeid != master) {
if (is_master(r))
dlm_purge_mstcpy_locks(r);
set_new_master(r, master);
return 1;
}
return 0;
lock_rsb(r);
dlm_purge_mstcpy_locks(r);
set_new_master(r, new_master);
unlock_rsb(r);
return 1;
}
/*
@@ -481,7 +493,9 @@ int dlm_recover_master_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
if (nodeid == dlm_our_nodeid())
nodeid = 0;
lock_rsb(r);
set_new_master(r, nodeid);
unlock_rsb(r);
recover_list_del(r);
if (recover_list_empty(ls))
@@ -556,8 +570,6 @@ int dlm_recover_locks(struct dlm_ls *ls)
struct dlm_rsb *r;
int error, count = 0;
log_debug(ls, "dlm_recover_locks");
down_read(&ls->ls_root_sem);
list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
if (is_master(r)) {
@@ -584,7 +596,7 @@ int dlm_recover_locks(struct dlm_ls *ls)
}
up_read(&ls->ls_root_sem);
log_debug(ls, "dlm_recover_locks %d locks", count);
log_debug(ls, "dlm_recover_locks %d out", count);
error = dlm_wait_function(ls, &recover_list_empty);
out:
@@ -721,21 +733,19 @@ static void recover_conversion(struct dlm_rsb *r)
}
/* We've become the new master for this rsb and waiting/converting locks may
need to be granted in dlm_grant_after_purge() due to locks that may have
need to be granted in dlm_recover_grant() due to locks that may have
existed from a removed node. */
static void set_locks_purged(struct dlm_rsb *r)
static void recover_grant(struct dlm_rsb *r)
{
if (!list_empty(&r->res_waitqueue) || !list_empty(&r->res_convertqueue))
rsb_set_flag(r, RSB_LOCKS_PURGED);
rsb_set_flag(r, RSB_RECOVER_GRANT);
}
void dlm_recover_rsbs(struct dlm_ls *ls)
{
struct dlm_rsb *r;
int count = 0;
log_debug(ls, "dlm_recover_rsbs");
unsigned int count = 0;
down_read(&ls->ls_root_sem);
list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
@@ -744,7 +754,7 @@ void dlm_recover_rsbs(struct dlm_ls *ls)
if (rsb_flag(r, RSB_RECOVER_CONVERT))
recover_conversion(r);
if (rsb_flag(r, RSB_NEW_MASTER2))
set_locks_purged(r);
recover_grant(r);
recover_lvb(r);
count++;
}
@@ -754,7 +764,8 @@ void dlm_recover_rsbs(struct dlm_ls *ls)
}
up_read(&ls->ls_root_sem);
log_debug(ls, "dlm_recover_rsbs %d rsbs", count);
if (count)
log_debug(ls, "dlm_recover_rsbs %d done", count);
}
/* Create a single list of all root rsb's to be used during recovery */