All of lore.kernel.org
 help / color / mirror / Atom feed
From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
To: davem@davemloft.net, netdev@vger.kernel.org
Cc: yoshfuji@linux-ipv6.org
Subject: [RFC net-next 3/4] ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.
Date: Thu, 31 Jan 2013 04:27:52 +0900	[thread overview]
Message-ID: <51097438.1060302@linux-ipv6.org> (raw)

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
---
 include/linux/ipv6.h     |    2 +-
 include/net/ipv6.h       |    1 +
 net/ipv6/ip6_flowlabel.c |   72 +++++++++++++++++++++++++---------------------
 3 files changed, 42 insertions(+), 33 deletions(-)

diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index e971e37..850e95b 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -214,7 +214,7 @@ struct ipv6_pinfo {
 
 	struct ipv6_mc_socklist	__rcu *ipv6_mc_list;
 	struct ipv6_ac_socklist	*ipv6_ac_list;
-	struct ipv6_fl_socklist *ipv6_fl_list;
+	struct ipv6_fl_socklist __rcu *ipv6_fl_list;
 
 	struct ipv6_txoptions	*opt;
 	struct sk_buff		*pktoptions;
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 1d45716..851d541 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -239,6 +239,7 @@ struct ip6_flowlabel {
 struct ipv6_fl_socklist {
 	struct ipv6_fl_socklist	*next;
 	struct ip6_flowlabel	*fl;
+	struct rcu_head		rcu;
 };
 
 extern struct ip6_flowlabel	*fl6_sock_lookup(struct sock *sk, __be32 label);
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index da15601..22494af 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -62,7 +62,7 @@ static DEFINE_SPINLOCK(ip6_fl_lock);
 
 /* Big socket sock */
 
-static DEFINE_RWLOCK(ip6_sk_fl_lock);
+static DEFINE_SPINLOCK(ip6_sk_fl_lock);
 
 #define for_each_fl_rcu(hash, fl)				\
 	for (fl = rcu_dereference(fl_ht[(hash)]);		\
@@ -73,6 +73,11 @@ static DEFINE_RWLOCK(ip6_sk_fl_lock);
 	     fl != NULL;					\
 	     fl = rcu_dereference(fl->next))
 
+#define for_each_sk_fl_rcu(np, sfl)				\
+	for (sfl = rcu_dereference_bh(np->ipv6_fl_list);	\
+	     sfl != NULL;					\
+	     sfl = rcu_dereference_bh(sfl->next))
+
 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
 {
 	struct ip6_flowlabel *fl;
@@ -244,17 +249,17 @@ struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label)
 
 	label &= IPV6_FLOWLABEL_MASK;
 
-	read_lock_bh(&ip6_sk_fl_lock);
-	for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
+	rcu_read_lock_bh();
+	for_each_sk_fl_rcu(np, sfl) {
 		struct ip6_flowlabel *fl = sfl->fl;
 		if (fl->label == label) {
 			fl->lastuse = jiffies;
 			atomic_inc(&fl->users);
-			read_unlock_bh(&ip6_sk_fl_lock);
+			rcu_read_unlock_bh();
 			return fl;
 		}
 	}
-	read_unlock_bh(&ip6_sk_fl_lock);
+	rcu_read_unlock_bh();
 	return NULL;
 }
 
@@ -265,20 +270,21 @@ void fl6_free_socklist(struct sock *sk)
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct ipv6_fl_socklist *sfl;
 
-	if (!np->ipv6_fl_list)
+	if (!rcu_access_pointer(np->ipv6_fl_list))
 		return;
 
-	write_lock_bh(&ipv6_sk_fl_lock);
-	sfl = np->ipv6_fl_list;
-	np->ipv6_fl_list = NULL;
-	write_unlock_bh(&ipv6_sk_fl_lock);
+	spin_lock_bh(&ip6_sk_fl_lock);
+	while ((sfl = rcu_dereference_protected(np->ipv6_fl_list,
+						lockdep_is_held(&ip6_sk_fl_lock))) != NULL) {
+		np->ipv6_fl_list = sfl->next;
+		spin_unlock_bh(&ip6_sk_fl_lock);
 
-	while (sfl) {
-		struct ipv6_fl_socklist *next = sfl->next;
 		fl_release(sfl->fl);
-		kfree(sfl);
-		sfl = next;
+		kfree_rcu(sfl, rcu);
+
+		spin_lock_bh(&ip6_sk_fl_lock);
 	}
+	spin_unlock_bh(&ip6_sk_fl_lock);
 }
 
 /* Service routines */
@@ -443,7 +449,7 @@ static int mem_check(struct sock *sk)
 	if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
 		return 0;
 
-	for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next)
+	for_each_sk_fl_rcu(np, sfl)
 		count++;
 
 	if (room <= 0 ||
@@ -486,11 +492,11 @@ static bool ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
 		struct ip6_flowlabel *fl)
 {
-	write_lock_bh(&ip6_sk_fl_lock);
+	spin_lock_bh(&ip6_sk_fl_lock);
 	sfl->fl = fl;
 	sfl->next = np->ipv6_fl_list;
-	np->ipv6_fl_list = sfl;
-	write_unlock_bh(&ip6_sk_fl_lock);
+	rcu_assign_pointer(np->ipv6_fl_list, sfl);
+	spin_unlock_bh(&ip6_sk_fl_lock);
 }
 
 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
@@ -512,31 +518,33 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
 
 	switch (freq.flr_action) {
 	case IPV6_FL_A_PUT:
-		write_lock_bh(&ip6_sk_fl_lock);
-		for (sflp = &np->ipv6_fl_list; (sfl=*sflp)!=NULL; sflp = &sfl->next) {
+		spin_lock_bh(&ip6_sk_fl_lock);
+		for (sflp = &np->ipv6_fl_list;
+		     (sfl = rcu_dereference(*sflp))!=NULL;
+		     sflp = &sfl->next) {
 			if (sfl->fl->label == freq.flr_label) {
 				if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
 					np->flow_label &= ~IPV6_FLOWLABEL_MASK;
-				*sflp = sfl->next;
-				write_unlock_bh(&ip6_sk_fl_lock);
+				*sflp = rcu_dereference(sfl->next);
+				spin_unlock_bh(&ip6_sk_fl_lock);
 				fl_release(sfl->fl);
-				kfree(sfl);
+				kfree_rcu(sfl, rcu);
 				return 0;
 			}
 		}
-		write_unlock_bh(&ip6_sk_fl_lock);
+		spin_unlock_bh(&ip6_sk_fl_lock);
 		return -ESRCH;
 
 	case IPV6_FL_A_RENEW:
-		read_lock_bh(&ip6_sk_fl_lock);
-		for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
+		rcu_read_lock_bh();
+		for_each_sk_fl_rcu(np, sfl) {
 			if (sfl->fl->label == freq.flr_label) {
 				err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
-				read_unlock_bh(&ip6_sk_fl_lock);
+				rcu_read_unlock_bh();
 				return err;
 			}
 		}
-		read_unlock_bh(&ip6_sk_fl_lock);
+		rcu_read_unlock_bh();
 
 		if (freq.flr_share == IPV6_FL_S_NONE &&
 		    ns_capable(net->user_ns, CAP_NET_ADMIN)) {
@@ -560,11 +568,11 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
 
 		if (freq.flr_label) {
 			err = -EEXIST;
-			read_lock_bh(&ip6_sk_fl_lock);
-			for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
+			rcu_read_lock_bh();
+			for_each_sk_fl_rcu(np, sfl) {
 				if (sfl->fl->label == freq.flr_label) {
 					if (freq.flr_flags&IPV6_FL_F_EXCL) {
-						read_unlock_bh(&ip6_sk_fl_lock);
+						rcu_read_unlock_bh();
 						goto done;
 					}
 					fl1 = sfl->fl;
@@ -572,7 +580,7 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
 					break;
 				}
 			}
-			read_unlock_bh(&ip6_sk_fl_lock);
+			rcu_read_unlock_bh();
 
 			if (fl1 == NULL)
 				fl1 = fl_lookup(net, freq.flr_label);
-- 
1.7.9.5

             reply	other threads:[~2013-01-30 19:27 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-01-30 19:27 YOSHIFUJI Hideaki [this message]
2013-01-31  3:41 ` [RFC net-next 3/4] ipv6 flowlabel: Convert np->ipv6_fl_list to RCU David Miller

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=51097438.1060302@linux-ipv6.org \
    --to=yoshfuji@linux-ipv6.org \
    --cc=davem@davemloft.net \
    --cc=netdev@vger.kernel.org \
    /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.