All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jiri Pirko <jiri@resnulli.us>
To: netdev@vger.kernel.org
Cc: davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com,
	edumazet@google.com, tariqt@nvidia.com, moshe@nvidia.com,
	saeedm@nvidia.com, linux-rdma@vger.kernel.org
Subject: [patch net-next v4 04/13] net: devlink: take RTNL in port_fill() function only if it is not held
Date: Wed,  2 Nov 2022 17:02:02 +0100	[thread overview]
Message-ID: <20221102160211.662752-5-jiri@resnulli.us> (raw)
In-Reply-To: <20221102160211.662752-1-jiri@resnulli.us>

From: Jiri Pirko <jiri@nvidia.com>

Follow-up patch is going to introduce a netdevice notifier event
processing which is called with RTNL mutex held. Processing of this will
eventually lead to call to port_notity() and port_fill() which currently
takes RTNL mutex internally. So as a temporary solution, propagate a
bool indicating if the mutex is already held. This will go away in one
of the follow-up patches.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 net/core/devlink.c | 46 +++++++++++++++++++++++++++++++---------------
 1 file changed, 31 insertions(+), 15 deletions(-)

diff --git a/net/core/devlink.c b/net/core/devlink.c
index ff81a5a5087c..3387dfbb80c5 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -1278,7 +1278,8 @@ devlink_nl_port_function_attrs_put(struct sk_buff *msg, struct devlink_port *por
 static int devlink_nl_port_fill(struct sk_buff *msg,
 				struct devlink_port *devlink_port,
 				enum devlink_command cmd, u32 portid, u32 seq,
-				int flags, struct netlink_ext_ack *extack)
+				int flags, struct netlink_ext_ack *extack,
+				bool rtnl_held)
 {
 	struct devlink *devlink = devlink_port->devlink;
 	void *hdr;
@@ -1293,7 +1294,8 @@ static int devlink_nl_port_fill(struct sk_buff *msg,
 		goto nla_put_failure;
 
 	/* Hold rtnl lock while accessing port's netdev attributes. */
-	rtnl_lock();
+	if (!rtnl_held)
+		rtnl_lock();
 	spin_lock_bh(&devlink_port->type_lock);
 	if (nla_put_u16(msg, DEVLINK_ATTR_PORT_TYPE, devlink_port->type))
 		goto nla_put_failure_type_locked;
@@ -1321,7 +1323,8 @@ static int devlink_nl_port_fill(struct sk_buff *msg,
 			goto nla_put_failure_type_locked;
 	}
 	spin_unlock_bh(&devlink_port->type_lock);
-	rtnl_unlock();
+	if (!rtnl_held)
+		rtnl_unlock();
 	if (devlink_nl_port_attrs_put(msg, devlink_port))
 		goto nla_put_failure;
 	if (devlink_nl_port_function_attrs_put(msg, devlink_port, extack))
@@ -1336,14 +1339,15 @@ static int devlink_nl_port_fill(struct sk_buff *msg,
 
 nla_put_failure_type_locked:
 	spin_unlock_bh(&devlink_port->type_lock);
-	rtnl_unlock();
+	if (!rtnl_held)
+		rtnl_unlock();
 nla_put_failure:
 	genlmsg_cancel(msg, hdr);
 	return -EMSGSIZE;
 }
 
-static void devlink_port_notify(struct devlink_port *devlink_port,
-				enum devlink_command cmd)
+static void __devlink_port_notify(struct devlink_port *devlink_port,
+				  enum devlink_command cmd, bool rtnl_held)
 {
 	struct devlink *devlink = devlink_port->devlink;
 	struct sk_buff *msg;
@@ -1358,7 +1362,8 @@ static void devlink_port_notify(struct devlink_port *devlink_port,
 	if (!msg)
 		return;
 
-	err = devlink_nl_port_fill(msg, devlink_port, cmd, 0, 0, 0, NULL);
+	err = devlink_nl_port_fill(msg, devlink_port, cmd, 0, 0, 0, NULL,
+				   rtnl_held);
 	if (err) {
 		nlmsg_free(msg);
 		return;
@@ -1368,6 +1373,12 @@ static void devlink_port_notify(struct devlink_port *devlink_port,
 				0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
 }
 
+static void devlink_port_notify(struct devlink_port *devlink_port,
+				enum devlink_command cmd)
+{
+	__devlink_port_notify(devlink_port, cmd, false);
+}
+
 static void devlink_rate_notify(struct devlink_rate *devlink_rate,
 				enum devlink_command cmd)
 {
@@ -1531,7 +1542,7 @@ static int devlink_nl_cmd_port_get_doit(struct sk_buff *skb,
 
 	err = devlink_nl_port_fill(msg, devlink_port, DEVLINK_CMD_PORT_NEW,
 				   info->snd_portid, info->snd_seq, 0,
-				   info->extack);
+				   info->extack, false);
 	if (err) {
 		nlmsg_free(msg);
 		return err;
@@ -1561,7 +1572,8 @@ static int devlink_nl_cmd_port_get_dumpit(struct sk_buff *msg,
 						   DEVLINK_CMD_NEW,
 						   NETLINK_CB(cb->skb).portid,
 						   cb->nlh->nlmsg_seq,
-						   NLM_F_MULTI, cb->extack);
+						   NLM_F_MULTI, cb->extack,
+						   false);
 			if (err) {
 				devl_unlock(devlink);
 				devlink_put(devlink);
@@ -1773,7 +1785,8 @@ static int devlink_port_new_notify(struct devlink *devlink,
 	}
 
 	err = devlink_nl_port_fill(msg, devlink_port, DEVLINK_CMD_NEW,
-				   info->snd_portid, info->snd_seq, 0, NULL);
+				   info->snd_portid, info->snd_seq, 0, NULL,
+				   false);
 	if (err)
 		goto out;
 
@@ -10033,7 +10046,7 @@ static void devlink_port_type_netdev_checks(struct devlink_port *devlink_port,
 
 static void __devlink_port_type_set(struct devlink_port *devlink_port,
 				    enum devlink_port_type type,
-				    void *type_dev)
+				    void *type_dev, bool rtnl_held)
 {
 	struct net_device *netdev = type_dev;
 
@@ -10060,7 +10073,7 @@ static void __devlink_port_type_set(struct devlink_port *devlink_port,
 		break;
 	}
 	spin_unlock_bh(&devlink_port->type_lock);
-	devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_NEW);
+	__devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_NEW, rtnl_held);
 }
 
 /**
@@ -10077,7 +10090,8 @@ void devlink_port_type_eth_set(struct devlink_port *devlink_port,
 			 "devlink port type for port %d set to Ethernet without a software interface reference, device type not supported by the kernel?\n",
 			 devlink_port->index);
 
-	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_ETH, netdev);
+	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_ETH, netdev,
+				false);
 }
 EXPORT_SYMBOL_GPL(devlink_port_type_eth_set);
 
@@ -10090,7 +10104,8 @@ EXPORT_SYMBOL_GPL(devlink_port_type_eth_set);
 void devlink_port_type_ib_set(struct devlink_port *devlink_port,
 			      struct ib_device *ibdev)
 {
-	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_IB, ibdev);
+	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_IB, ibdev,
+				false);
 }
 EXPORT_SYMBOL_GPL(devlink_port_type_ib_set);
 
@@ -10101,7 +10116,8 @@ EXPORT_SYMBOL_GPL(devlink_port_type_ib_set);
  */
 void devlink_port_type_clear(struct devlink_port *devlink_port)
 {
-	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_NOTSET, NULL);
+	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_NOTSET, NULL,
+				false);
 }
 EXPORT_SYMBOL_GPL(devlink_port_type_clear);
 
-- 
2.37.3


  parent reply	other threads:[~2022-11-02 16:02 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-02 16:01 [patch net-next v4 00/13] net: fix netdev to devlink_port linkage and expose to user Jiri Pirko
2022-11-02 16:01 ` [patch net-next v4 01/13] net: devlink: convert devlink port type-specific pointers to union Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 02/13] net: devlink: move port_type_warn_schedule() call to __devlink_port_type_set() Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 03/13] net: devlink: move port_type_netdev_checks() " Jiri Pirko
2022-11-02 16:02 ` Jiri Pirko [this message]
2022-11-02 16:02 ` [patch net-next v4 05/13] net: devlink: track netdev with devlink_port assigned Jiri Pirko
2022-11-06  9:09   ` Ido Schimmel
2022-11-07  7:40     ` Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 06/13] net: make drivers to use SET_NETDEV_DEVLINK_PORT to set devlink_port Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 07/13] net: devlink: remove netdev arg from devlink_port_type_eth_set() Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 08/13] net: devlink: remove net namespace check from devlink_nl_port_fill() Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 09/13] net: devlink: store copy netdevice ifindex and ifname to allow port_fill() without RTNL held Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 10/13] net: devlink: add not cleared type warning to port unregister Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 11/13] net: devlink: use devlink_port pointer instead of ndo_get_devlink_port Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 12/13] net: remove unused ndo_get_devlink_port Jiri Pirko
2022-11-02 16:02 ` [patch net-next v4 13/13] net: expose devlink port over rtnetlink Jiri Pirko
2022-11-04  5:00 ` [patch net-next v4 00/13] net: fix netdev to devlink_port linkage and expose to user patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20221102160211.662752-5-jiri@resnulli.us \
    --to=jiri@resnulli.us \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=kuba@kernel.org \
    --cc=linux-rdma@vger.kernel.org \
    --cc=moshe@nvidia.com \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=saeedm@nvidia.com \
    --cc=tariqt@nvidia.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.