On Tue, 16 Apr 2024, Lorenzo Bianconi wrote:
> Introduce write_threads netlink command similar to the one available
> through the procfs.
I think this should support write_pool_threads too.
i.e. the number of threads should be an array. If it is a singleton,
the it does write_threads. If larger it does write_pool_threads.
I don't think we want to add a separate command later for pool_threads.
NeilBrown
>
> Tested-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Co-developed-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
> ---
> Documentation/netlink/specs/nfsd.yaml | 33 ++++++++
> fs/nfsd/netlink.c | 19 +++++
> fs/nfsd/netlink.h | 2 +
> fs/nfsd/nfsctl.c | 104 ++++++++++++++++++++++++++
> include/uapi/linux/nfsd_netlink.h | 11 +++
> 5 files changed, 169 insertions(+)
>
> diff --git a/Documentation/netlink/specs/nfsd.yaml b/Documentation/netlink/specs/nfsd.yaml
> index 05acc73e2e33..cbe6c5fd6c4d 100644
> --- a/Documentation/netlink/specs/nfsd.yaml
> +++ b/Documentation/netlink/specs/nfsd.yaml
> @@ -62,6 +62,18 @@ attribute-sets:
> name: compound-ops
> type: u32
> multi-attr: true
> + -
> + name: server-worker
> + attributes:
> + -
> + name: threads
> + type: u32
> + -
> + name: gracetime
> + type: u32
> + -
> + name: leasetime
> + type: u32
>
> operations:
> list:
> @@ -87,3 +99,24 @@ operations:
> - sport
> - dport
> - compound-ops
> + -
> + name: threads-set
> + doc: set the number of running threads
> + attribute-set: server-worker
> + flags: [ admin-perm ]
> + do:
> + request:
> + attributes:
> + - threads
> + - gracetime
> + - leasetime
> + -
> + name: threads-get
> + doc: get the number of running threads
> + attribute-set: server-worker
> + do:
> + reply:
> + attributes:
> + - threads
> + - gracetime
> + - leasetime
> diff --git a/fs/nfsd/netlink.c b/fs/nfsd/netlink.c
> index 0e1d635ec5f9..20a646af0324 100644
> --- a/fs/nfsd/netlink.c
> +++ b/fs/nfsd/netlink.c
> @@ -10,6 +10,13 @@
>
> #include <uapi/linux/nfsd_netlink.h>
>
> +/* NFSD_CMD_THREADS_SET - do */
> +static const struct nla_policy nfsd_threads_set_nl_policy[NFSD_A_SERVER_WORKER_LEASETIME + 1] = {
> + [NFSD_A_SERVER_WORKER_THREADS] = { .type = NLA_U32, },
> + [NFSD_A_SERVER_WORKER_GRACETIME] = { .type = NLA_U32, },
> + [NFSD_A_SERVER_WORKER_LEASETIME] = { .type = NLA_U32, },
> +};
> +
> /* Ops table for nfsd */
> static const struct genl_split_ops nfsd_nl_ops[] = {
> {
> @@ -19,6 +26,18 @@ static const struct genl_split_ops nfsd_nl_ops[] = {
> .done = nfsd_nl_rpc_status_get_done,
> .flags = GENL_CMD_CAP_DUMP,
> },
> + {
> + .cmd = NFSD_CMD_THREADS_SET,
> + .doit = nfsd_nl_threads_set_doit,
> + .policy = nfsd_threads_set_nl_policy,
> + .maxattr = NFSD_A_SERVER_WORKER_LEASETIME,
> + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
> + },
> + {
> + .cmd = NFSD_CMD_THREADS_GET,
> + .doit = nfsd_nl_threads_get_doit,
> + .flags = GENL_CMD_CAP_DO,
> + },
> };
>
> struct genl_family nfsd_nl_family __ro_after_init = {
> diff --git a/fs/nfsd/netlink.h b/fs/nfsd/netlink.h
> index d83dd6bdee92..4137fac477e4 100644
> --- a/fs/nfsd/netlink.h
> +++ b/fs/nfsd/netlink.h
> @@ -16,6 +16,8 @@ int nfsd_nl_rpc_status_get_done(struct netlink_callback *cb);
>
> int nfsd_nl_rpc_status_get_dumpit(struct sk_buff *skb,
> struct netlink_callback *cb);
> +int nfsd_nl_threads_set_doit(struct sk_buff *skb, struct genl_info *info);
> +int nfsd_nl_threads_get_doit(struct sk_buff *skb, struct genl_info *info);
>
> extern struct genl_family nfsd_nl_family;
>
> diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
> index f2e442d7fe16..38a5df03981b 100644
> --- a/fs/nfsd/nfsctl.c
> +++ b/fs/nfsd/nfsctl.c
> @@ -1653,6 +1653,110 @@ int nfsd_nl_rpc_status_get_done(struct netlink_callback *cb)
> return 0;
> }
>
> +/**
> + * nfsd_nl_threads_set_doit - set the number of running threads
> + * @skb: reply buffer
> + * @info: netlink metadata and command arguments
> + *
> + * Return 0 on success or a negative errno.
> + */
> +int nfsd_nl_threads_set_doit(struct sk_buff *skb, struct genl_info *info)
> +{
> + struct net *net = genl_info_net(info);
> + struct nfsd_net *nn = net_generic(net, nfsd_net_id);
> + int ret = -EBUSY;
> + u32 nthreads;
> +
> + if (GENL_REQ_ATTR_CHECK(info, NFSD_A_SERVER_WORKER_THREADS))
> + return -EINVAL;
> +
> + nthreads = nla_get_u32(info->attrs[NFSD_A_SERVER_WORKER_THREADS]);
> +
> + mutex_lock(&nfsd_mutex);
> + if (info->attrs[NFSD_A_SERVER_WORKER_GRACETIME] ||
> + info->attrs[NFSD_A_SERVER_WORKER_LEASETIME]) {
> + const struct nlattr *attr;
> +
> + if (nn->nfsd_serv && nn->nfsd_serv->sv_nrthreads)
> + goto out_unlock;
> +
> + ret = -EINVAL;
> + attr = info->attrs[NFSD_A_SERVER_WORKER_GRACETIME];
> + if (attr) {
> + u32 gracetime = nla_get_u32(attr);
> +
> + if (gracetime < 10 || gracetime > 3600)
> + goto out_unlock;
> +
> + nn->nfsd4_grace = gracetime;
> + }
> +
> + attr = info->attrs[NFSD_A_SERVER_WORKER_LEASETIME];
> + if (attr) {
> + u32 leasetime = nla_get_u32(attr);
> +
> + if (leasetime < 10 || leasetime > 3600)
> + goto out_unlock;
> +
> + nn->nfsd4_lease = leasetime;
> + }
> + }
> +
> + ret = nfsd_svc(nthreads, net, get_current_cred());
> +out_unlock:
> + mutex_unlock(&nfsd_mutex);
> +
> + return ret == nthreads ? 0 : ret;
> +}
> +
> +/**
> + * nfsd_nl_threads_get_doit - get the number of running threads
> + * @skb: reply buffer
> + * @info: netlink metadata and command arguments
> + *
> + * Return 0 on success or a negative errno.
> + */
> +int nfsd_nl_threads_get_doit(struct sk_buff *skb, struct genl_info *info)
> +{
> + struct net *net = genl_info_net(info);
> + struct nfsd_net *nn = net_generic(net, nfsd_net_id);
> + void *hdr;
> + int err;
> +
> + skb = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
> + if (!skb)
> + return -ENOMEM;
> +
> + hdr = genlmsg_iput(skb, info);
> + if (!hdr) {
> + err = -EMSGSIZE;
> + goto err_free_msg;
> + }
> +
> + mutex_lock(&nfsd_mutex);
> + err = nla_put_u32(skb, NFSD_A_SERVER_WORKER_GRACETIME,
> + nn->nfsd4_grace) ||
> + nla_put_u32(skb, NFSD_A_SERVER_WORKER_LEASETIME,
> + nn->nfsd4_lease) ||
> + nla_put_u32(skb, NFSD_A_SERVER_WORKER_THREADS,
> + nn->nfsd_serv ? nn->nfsd_serv->sv_nrthreads : 0);
> + mutex_unlock(&nfsd_mutex);
> +
> + if (err) {
> + err = -EINVAL;
> + goto err_free_msg;
> + }
> +
> + genlmsg_end(skb, hdr);
> +
> + return genlmsg_reply(skb, info);
> +
> +err_free_msg:
> + nlmsg_free(skb);
> +
> + return err;
> +}
> +
> /**
> * nfsd_net_init - Prepare the nfsd_net portion of a new net namespace
> * @net: a freshly-created network namespace
> diff --git a/include/uapi/linux/nfsd_netlink.h b/include/uapi/linux/nfsd_netlink.h
> index 3cd044edee5d..ccc78a5ee650 100644
> --- a/include/uapi/linux/nfsd_netlink.h
> +++ b/include/uapi/linux/nfsd_netlink.h
> @@ -29,8 +29,19 @@ enum {
> NFSD_A_RPC_STATUS_MAX = (__NFSD_A_RPC_STATUS_MAX - 1)
> };
>
> +enum {
> + NFSD_A_SERVER_WORKER_THREADS = 1,
> + NFSD_A_SERVER_WORKER_GRACETIME,
> + NFSD_A_SERVER_WORKER_LEASETIME,
> +
> + __NFSD_A_SERVER_WORKER_MAX,
> + NFSD_A_SERVER_WORKER_MAX = (__NFSD_A_SERVER_WORKER_MAX - 1)
> +};
> +
> enum {
> NFSD_CMD_RPC_STATUS_GET = 1,
> + NFSD_CMD_THREADS_SET,
> + NFSD_CMD_THREADS_GET,
>
> __NFSD_CMD_MAX,
> NFSD_CMD_MAX = (__NFSD_CMD_MAX - 1)
> --
> 2.44.0
>
>
