From 4e69489a0ac11a9b62a25923975bfc370a30eae5 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 4 Apr 2009 16:41:09 -0700 Subject: socket: use percpu_add() while updating sockets_in_use sock_alloc() currently uses following code to update sockets_in_use get_cpu_var(sockets_in_use)++; put_cpu_var(sockets_in_use); This translates to : c0436274: b8 01 00 00 00 mov $0x1,%eax c0436279: e8 42 40 df ff call c022a2c0 c043627e: bb 20 4f 6a c0 mov $0xc06a4f20,%ebx c0436283: e8 18 ca f0 ff call c0342ca0 c0436288: 03 1c 85 60 4a 65 c0 add -0x3f9ab5a0(,%eax,4),%ebx c043628f: ff 03 incl (%ebx) c0436291: b8 01 00 00 00 mov $0x1,%eax c0436296: e8 75 3f df ff call c022a210 c043629b: 89 e0 mov %esp,%eax c043629d: 25 00 e0 ff ff and $0xffffe000,%eax c04362a2: f6 40 08 08 testb $0x8,0x8(%eax) c04362a6: 75 07 jne c04362af c04362a8: 8d 46 d8 lea -0x28(%esi),%eax c04362ab: 5b pop %ebx c04362ac: 5e pop %esi c04362ad: c9 leave c04362ae: c3 ret c04362af: e8 cc 5d 09 00 call c04cc080 c04362b4: 8d 74 26 00 lea 0x0(%esi,%eiz,1),%esi c04362b8: eb ee jmp c04362a8 While percpu_add(sockets_in_use, 1) translates to a single instruction : c0436275: 64 83 05 20 5f 6a c0 addl $0x1,%fs:0xc06a5f20 Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/socket.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'net') diff --git a/net/socket.c b/net/socket.c index 0b14b79c03af..7d5ebc0eb69e 100644 --- a/net/socket.c +++ b/net/socket.c @@ -493,8 +493,7 @@ static struct socket *sock_alloc(void) inode->i_uid = current_fsuid(); inode->i_gid = current_fsgid(); - get_cpu_var(sockets_in_use)++; - put_cpu_var(sockets_in_use); + percpu_add(sockets_in_use, 1); return sock; } @@ -536,8 +535,7 @@ void sock_release(struct socket *sock) if (sock->fasync_list) printk(KERN_ERR "sock_release: fasync list not empty!\n"); - get_cpu_var(sockets_in_use)--; - put_cpu_var(sockets_in_use); + percpu_sub(sockets_in_use, 1); if (!sock->file) { iput(SOCK_INODE(sock)); return; -- cgit v1.2.2