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Message-Id: <1267043958-31082-3-git-send-email-teigland@redhat.com>
Date: Wed, 24 Feb 2010 14:39:17 -0600
From: David Teigland <teigland@...hat.com>
To: linux-kernel@...r.kernel.org
Subject: [PATCH 2/3] dlm: send reply before bast
When the lock master processes a successful convert or request,
it will process the effects of that change before sending the
reply for the convert/request. The effects are:
- blocking callbacks (basts) for the newly granted locks
- waiting or converting locks that can now be granted
The cast is queued on the local node when the reply from the lock
master is received. This means that a lock holder can receive a
bast for a lock mode that is doesn't yet know has been granted.
Signed-off-by: David Teigland <teigland@...hat.com>
---
fs/dlm/lock.c | 69 +++++++++++++++++++++++++++++++++++++++++++--------------
1 files changed, 52 insertions(+), 17 deletions(-)
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index e08ea93..4f99a4e 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -2280,20 +2280,30 @@ static int do_request(struct dlm_rsb *r, struct dlm_lkb *lkb)
if (can_be_queued(lkb)) {
error = -EINPROGRESS;
add_lkb(r, lkb, DLM_LKSTS_WAITING);
- send_blocking_asts(r, lkb);
add_timeout(lkb);
goto out;
}
error = -EAGAIN;
- if (force_blocking_asts(lkb))
- send_blocking_asts_all(r, lkb);
queue_cast(r, lkb, -EAGAIN);
-
out:
return error;
}
+static void do_request_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
+ int error)
+{
+ switch (error) {
+ case -EAGAIN:
+ if (force_blocking_asts(lkb))
+ send_blocking_asts_all(r, lkb);
+ break;
+ case -EINPROGRESS:
+ send_blocking_asts(r, lkb);
+ break;
+ }
+}
+
static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
{
int error = 0;
@@ -2304,7 +2314,6 @@ static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
if (can_be_granted(r, lkb, 1, &deadlk)) {
grant_lock(r, lkb);
queue_cast(r, lkb, 0);
- grant_pending_locks(r);
goto out;
}
@@ -2334,7 +2343,6 @@ static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
if (_can_be_granted(r, lkb, 1)) {
grant_lock(r, lkb);
queue_cast(r, lkb, 0);
- grant_pending_locks(r);
goto out;
}
/* else fall through and move to convert queue */
@@ -2344,20 +2352,34 @@ static int do_convert(struct dlm_rsb *r, struct dlm_lkb *lkb)
error = -EINPROGRESS;
del_lkb(r, lkb);
add_lkb(r, lkb, DLM_LKSTS_CONVERT);
- send_blocking_asts(r, lkb);
add_timeout(lkb);
goto out;
}
error = -EAGAIN;
- if (force_blocking_asts(lkb))
- send_blocking_asts_all(r, lkb);
queue_cast(r, lkb, -EAGAIN);
-
out:
return error;
}
+static void do_convert_effects(struct dlm_rsb *r, struct dlm_lkb *lkb,
+ int error)
+{
+ switch (error) {
+ case 0:
+ grant_pending_locks(r);
+ /* grant_pending_locks also sends basts */
+ break;
+ case -EAGAIN:
+ if (force_blocking_asts(lkb))
+ send_blocking_asts_all(r, lkb);
+ break;
+ case -EINPROGRESS:
+ send_blocking_asts(r, lkb);
+ break;
+ }
+}
+
static int do_unlock(struct dlm_rsb *r, struct dlm_lkb *lkb)
{
remove_lock(r, lkb);
@@ -2402,11 +2424,15 @@ static int _request_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
goto out;
}
- if (is_remote(r))
+ if (is_remote(r)) {
/* receive_request() calls do_request() on remote node */
error = send_request(r, lkb);
- else
+ } else {
error = do_request(r, lkb);
+ /* for remote locks the request_reply is sent
+ between do_request and do_request_effects */
+ do_request_effects(r, lkb, error);
+ }
out:
return error;
}
@@ -2417,11 +2443,15 @@ static int _convert_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
{
int error;
- if (is_remote(r))
+ if (is_remote(r)) {
/* receive_convert() calls do_convert() on remote node */
error = send_convert(r, lkb);
- else
+ } else {
error = do_convert(r, lkb);
+ /* for remote locks the convert_reply is sent
+ between do_convert and do_convert_effects */
+ do_convert_effects(r, lkb, error);
+ }
return error;
}
@@ -3191,6 +3221,7 @@ static void receive_request(struct dlm_ls *ls, struct dlm_message *ms)
attach_lkb(r, lkb);
error = do_request(r, lkb);
send_request_reply(r, lkb, error);
+ do_request_effects(r, lkb, error);
unlock_rsb(r);
put_rsb(r);
@@ -3226,15 +3257,19 @@ static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
goto out;
receive_flags(lkb, ms);
+
error = receive_convert_args(ls, lkb, ms);
- if (error)
- goto out_reply;
+ if (error) {
+ send_convert_reply(r, lkb, error);
+ goto out;
+ }
+
reply = !down_conversion(lkb);
error = do_convert(r, lkb);
- out_reply:
if (reply)
send_convert_reply(r, lkb, error);
+ do_convert_effects(r, lkb, error);
out:
unlock_rsb(r);
put_rsb(r);
--
1.6.6
--
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