coallocate socket_wq with socket itself

socket->wq is assign-once, set when we are initializing both
struct socket it's in and struct socket_wq it points to.  As the
matter of fact, the only reason for separate allocation was the
ability to RCU-delay freeing of socket_wq.  RCU-delaying the
freeing of socket itself gets rid of that need, so we can just
fold struct socket_wq into the end of struct socket and simplify
the life both for sock_alloc_inode() (one allocation instead of
two) and for tun/tap oddballs, where we used to embed struct socket
and struct socket_wq into the same structure (now - embedding just
the struct socket).

Note that reference to struct socket_wq in struct sock does remain
a reference - that's unchanged.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/tap.c b/drivers/net/tap.c
index 8e01390c738e8ce0a01c16a6cca2865df02d6c04..dd614c2cd994e89c66eb37625b2afb79adec2258 100644 (file)
--- a/drivers/net/tap.c
+++ b/drivers/net/tap.c
@@ -520,8 +520,7 @@ static int tap_open(struct inode *inode, struct file *file)
                goto err;
        }
 
-       RCU_INIT_POINTER(q->sock.wq, &q->wq);
-       init_waitqueue_head(&q->wq.wait);
+       init_waitqueue_head(&q->sock.wq.wait);
        q->sock.type = SOCK_RAW;
        q->sock.state = SS_CONNECTED;
        q->sock.file = file;
@@ -579,7 +578,7 @@ static __poll_t tap_poll(struct file *file, poll_table *wait)
                goto out;
 
        mask = 0;
-       poll_wait(file, &q->wq.wait, wait);
+       poll_wait(file, &q->sock.wq.wait, wait);
 
        if (!ptr_ring_empty(&q->ring))
                mask |= EPOLLIN | EPOLLRDNORM;

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index d7c55e0fa8f4fa58bf723a066c81fab684973b7e..3d443597bd0496fc99e181f1df29a7ca70191125 100644 (file)
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -160,7 +160,6 @@ struct tun_pcpu_stats {
 struct tun_file {
        struct sock sk;
        struct socket socket;
-       struct socket_wq wq;
        struct tun_struct __rcu *tun;
        struct fasync_struct *fasync;
        /* only used for fasnyc */
@@ -2165,7 +2164,7 @@ static void *tun_ring_recv(struct tun_file *tfile, int noblock, int *err)
                goto out;
        }
 
-       add_wait_queue(&tfile->wq.wait, &wait);
+       add_wait_queue(&tfile->socket.wq.wait, &wait);
 
        while (1) {
                set_current_state(TASK_INTERRUPTIBLE);
@@ -2185,7 +2184,7 @@ static void *tun_ring_recv(struct tun_file *tfile, int noblock, int *err)
        }
 
        __set_current_state(TASK_RUNNING);
-       remove_wait_queue(&tfile->wq.wait, &wait);
+       remove_wait_queue(&tfile->socket.wq.wait, &wait);
 
 out:
        *err = error;
@@ -3415,8 +3414,7 @@ static int tun_chr_open(struct inode *inode, struct file * file)
        tfile->flags = 0;
        tfile->ifindex = 0;
 
-       init_waitqueue_head(&tfile->wq.wait);
-       RCU_INIT_POINTER(tfile->socket.wq, &tfile->wq);
+       init_waitqueue_head(&tfile->socket.wq.wait);
 
        tfile->socket.file = file;
        tfile->socket.ops = &tun_socket_ops;

diff --git a/include/linux/if_tap.h b/include/linux/if_tap.h
index 8e66866c11becbb31a1d2f14cd91977384a10584..915a187cfabdac61da21a58c9ab00862c9deaae8 100644 (file)
--- a/include/linux/if_tap.h
+++ b/include/linux/if_tap.h
@@ -62,7 +62,6 @@ struct tap_dev {
 struct tap_queue {
        struct sock sk;
        struct socket sock;
-       struct socket_wq wq;
        int vnet_hdr_sz;
        struct tap_dev __rcu *tap;
        struct file *file;

diff --git a/include/linux/net.h b/include/linux/net.h
index f7d672cf25b5a99c362885f5b2ff5cc64d5772d1..9cafb5f353a97c1948a61a527f239d8f802c0252 100644 (file)
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -116,11 +116,11 @@ struct socket {
 
        unsigned long           flags;
 
-       struct socket_wq        *wq;
-
        struct file             *file;
        struct sock             *sk;
        const struct proto_ops  *ops;
+
+       struct socket_wq        wq;
 };
 
 struct vm_area_struct;

diff --git a/include/net/sock.h b/include/net/sock.h
index 6cbc16136357d158cf1e84b98ecb7e06898269a6..228db3998e46e42156fec16e78f5e627669a9687 100644 (file)
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1822,7 +1822,7 @@ static inline void sock_graft(struct sock *sk, struct socket *parent)
 {
        WARN_ON(parent->sk);
        write_lock_bh(&sk->sk_callback_lock);
-       rcu_assign_pointer(sk->sk_wq, parent->wq);
+       rcu_assign_pointer(sk->sk_wq, &parent->wq);
        parent->sk = sk;
        sk_set_socket(sk, parent);
        sk->sk_uid = SOCK_INODE(parent)->i_uid;
@@ -2100,7 +2100,7 @@ static inline void sock_poll_wait(struct file *filp, struct socket *sock,
                                  poll_table *p)
 {
        if (!poll_does_not_wait(p)) {
-               poll_wait(filp, &sock->wq->wait, p);
+               poll_wait(filp, &sock->wq.wait, p);
                /* We need to be sure we are in sync with the
                 * socket flags modification.
                 *

diff --git a/net/core/sock.c b/net/core/sock.c
index 0eb21384079d2224a13c238be808a2c6766e962e..3e073ca6138fadaa75ff3a948de64ef45746123a 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2847,7 +2847,7 @@ void sock_init_data(struct socket *sock, struct sock *sk)
 
        if (sock) {
                sk->sk_type     =       sock->type;
-               RCU_INIT_POINTER(sk->sk_wq, sock->wq);
+               RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
                sock->sk        =       sk;
                sk->sk_uid      =       SOCK_INODE(sock)->i_uid;
        } else {

diff --git a/net/socket.c b/net/socket.c
index 541719a2443d875046a10d1d305d113eb53803f9..16449d6daeca214f4bdf979953a2481f29b52cab 100644 (file)
--- a/net/socket.c
+++ b/net/socket.c
@@ -234,20 +234,13 @@ static struct kmem_cache *sock_inode_cachep __ro_after_init;
 static struct inode *sock_alloc_inode(struct super_block *sb)
 {
        struct socket_alloc *ei;
-       struct socket_wq *wq;
 
        ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
        if (!ei)
                return NULL;
-       wq = kmalloc(sizeof(*wq), GFP_KERNEL);
-       if (!wq) {
-               kmem_cache_free(sock_inode_cachep, ei);
-               return NULL;
-       }
-       init_waitqueue_head(&wq->wait);
-       wq->fasync_list = NULL;
-       wq->flags = 0;
-       ei->socket.wq = wq;
+       init_waitqueue_head(&ei->socket.wq.wait);
+       ei->socket.wq.fasync_list = NULL;
+       ei->socket.wq.flags = 0;
 
        ei->socket.state = SS_UNCONNECTED;
        ei->socket.flags = 0;
@@ -263,7 +256,6 @@ static void sock_free_inode(struct inode *inode)
        struct socket_alloc *ei;
 
        ei = container_of(inode, struct socket_alloc, vfs_inode);
-       kfree(ei->socket.wq);
        kmem_cache_free(sock_inode_cachep, ei);
 }
 
@@ -599,7 +591,7 @@ static void __sock_release(struct socket *sock, struct inode *inode)
                module_put(owner);
        }
 
-       if (sock->wq->fasync_list)
+       if (sock->wq.fasync_list)
                pr_err("%s: fasync list not empty!\n", __func__);
 
        if (!sock->file) {
@@ -1288,13 +1280,12 @@ static int sock_fasync(int fd, struct file *filp, int on)
 {
        struct socket *sock = filp->private_data;
        struct sock *sk = sock->sk;
-       struct socket_wq *wq;
+       struct socket_wq *wq = &sock->wq;
 
        if (sk == NULL)
                return -EINVAL;
 
        lock_sock(sk);
-       wq = sock->wq;
        fasync_helper(fd, filp, on, &wq->fasync_list);
 
        if (!wq->fasync_list)