From 3f9bcca7820a6711307b6499952b13cfcfc31dd6 Mon Sep 17 00:00:00 2001 From: Suresh Jayaraman Date: Mon, 18 Oct 2010 23:29:37 +0530 Subject: cifs: convert cifs_tcp_ses_lock from a rwlock to a spinlock cifs_tcp_ses_lock is a rwlock with protects the cifs_tcp_ses_list, server->smb_ses_list and the ses->tcon_list. It also protects a few ref counters in server, ses and tcon. In most cases the critical section doesn't seem to be large, in a few cases where it is slightly large, there seem to be really no benefit from concurrent access. I briefly considered RCU mechanism but it appears to me that there is no real need. Replace it with a spinlock and get rid of the last rwlock in the cifs code. Signed-off-by: Suresh Jayaraman Signed-off-by: Steve French --- fs/cifs/sess.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/cifs/sess.c') diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index e35dc60d3255..2a11efd96592 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -80,7 +80,7 @@ static __le16 get_next_vcnum(struct cifsSesInfo *ses) if (max_vcs < 2) max_vcs = 0xFFFF; - write_lock(&cifs_tcp_ses_lock); + spin_lock(&cifs_tcp_ses_lock); if ((ses->need_reconnect) && is_first_ses_reconnect(ses)) goto get_vc_num_exit; /* vcnum will be zero */ for (i = ses->server->srv_count - 1; i < max_vcs; i++) { @@ -112,7 +112,7 @@ static __le16 get_next_vcnum(struct cifsSesInfo *ses) vcnum = i; ses->vcnum = vcnum; get_vc_num_exit: - write_unlock(&cifs_tcp_ses_lock); + spin_unlock(&cifs_tcp_ses_lock); return cpu_to_le16(vcnum); } -- cgit v1.2.2