2024-01-26 17:48:48

by Chuck Lever

[permalink] [raw]
Subject: [PATCH 2 02/14] NFSD: Convert the callback workqueue to use delayed_work

From: Chuck Lever <[email protected]>

Normally, NFSv4 callback operations are supposed to be sent to the
client as soon as they are queued up.

In a moment, I will introduce a recovery path where the server has
to wait for the client to reconnect. We don't want a hard busy wait
here -- the callback should be requeued to try again in several
milliseconds.

For now, convert nfsd4_callback from struct work_struct to struct
delayed_work, and queue with a zero delay argument. This should
avoid behavior changes for current operation.

Signed-off-by: Chuck Lever <[email protected]>
---
fs/nfsd/nfs4callback.c | 6 +++---
fs/nfsd/state.h | 2 +-
2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 43b0a34a5d5b..1ed2512b3648 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -887,7 +887,7 @@ static struct workqueue_struct *callback_wq;

static bool nfsd4_queue_cb(struct nfsd4_callback *cb)
{
- return queue_work(callback_wq, &cb->cb_work);
+ return queue_delayed_work(callback_wq, &cb->cb_work, 0);
}

static void nfsd41_cb_inflight_begin(struct nfs4_client *clp)
@@ -1370,7 +1370,7 @@ static void
nfsd4_run_cb_work(struct work_struct *work)
{
struct nfsd4_callback *cb =
- container_of(work, struct nfsd4_callback, cb_work);
+ container_of(work, struct nfsd4_callback, cb_work.work);
struct nfs4_client *clp = cb->cb_clp;
struct rpc_clnt *clnt;
int flags;
@@ -1415,7 +1415,7 @@ void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
cb->cb_msg.rpc_argp = cb;
cb->cb_msg.rpc_resp = cb;
cb->cb_ops = ops;
- INIT_WORK(&cb->cb_work, nfsd4_run_cb_work);
+ INIT_DELAYED_WORK(&cb->cb_work, nfsd4_run_cb_work);
cb->cb_seq_status = 1;
cb->cb_status = 0;
cb->cb_need_restart = false;
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 41bdc913fa71..87c4372ba36a 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -68,7 +68,7 @@ struct nfsd4_callback {
struct nfs4_client *cb_clp;
struct rpc_message cb_msg;
const struct nfsd4_callback_ops *cb_ops;
- struct work_struct cb_work;
+ struct delayed_work cb_work;
int cb_seq_status;
int cb_status;
bool cb_need_restart;




2024-01-26 19:10:07

by Jeff Layton

[permalink] [raw]
Subject: Re: [PATCH 2 02/14] NFSD: Convert the callback workqueue to use delayed_work

On Fri, 2024-01-26 at 12:45 -0500, Chuck Lever wrote:
> From: Chuck Lever <[email protected]>
>
> Normally, NFSv4 callback operations are supposed to be sent to the
> client as soon as they are queued up.
>
> In a moment, I will introduce a recovery path where the server has
> to wait for the client to reconnect. We don't want a hard busy wait
> here -- the callback should be requeued to try again in several
> milliseconds.
>
> For now, convert nfsd4_callback from struct work_struct to struct
> delayed_work, and queue with a zero delay argument. This should
> avoid behavior changes for current operation.
>
> Signed-off-by: Chuck Lever <[email protected]>
> ---
> fs/nfsd/nfs4callback.c | 6 +++---
> fs/nfsd/state.h | 2 +-
> 2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
> index 43b0a34a5d5b..1ed2512b3648 100644
> --- a/fs/nfsd/nfs4callback.c
> +++ b/fs/nfsd/nfs4callback.c
> @@ -887,7 +887,7 @@ static struct workqueue_struct *callback_wq;
>
> static bool nfsd4_queue_cb(struct nfsd4_callback *cb)
> {
> - return queue_work(callback_wq, &cb->cb_work);
> + return queue_delayed_work(callback_wq, &cb->cb_work, 0);
> }
>
> static void nfsd41_cb_inflight_begin(struct nfs4_client *clp)
> @@ -1370,7 +1370,7 @@ static void
> nfsd4_run_cb_work(struct work_struct *work)
> {
> struct nfsd4_callback *cb =
> - container_of(work, struct nfsd4_callback, cb_work);
> + container_of(work, struct nfsd4_callback, cb_work.work);
> struct nfs4_client *clp = cb->cb_clp;
> struct rpc_clnt *clnt;
> int flags;
> @@ -1415,7 +1415,7 @@ void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
> cb->cb_msg.rpc_argp = cb;
> cb->cb_msg.rpc_resp = cb;
> cb->cb_ops = ops;
> - INIT_WORK(&cb->cb_work, nfsd4_run_cb_work);
> + INIT_DELAYED_WORK(&cb->cb_work, nfsd4_run_cb_work);
> cb->cb_seq_status = 1;
> cb->cb_status = 0;
> cb->cb_need_restart = false;
> diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
> index 41bdc913fa71..87c4372ba36a 100644
> --- a/fs/nfsd/state.h
> +++ b/fs/nfsd/state.h
> @@ -68,7 +68,7 @@ struct nfsd4_callback {
> struct nfs4_client *cb_clp;
> struct rpc_message cb_msg;
> const struct nfsd4_callback_ops *cb_ops;
> - struct work_struct cb_work;
> + struct delayed_work cb_work;
> int cb_seq_status;
> int cb_status;
> bool cb_need_restart;
>
>
>

Reviewed-by: Jeff Layton <[email protected]>