From d7d7a66aacd6fd8ca57baf08a7bac5421282f6f8 Mon Sep 17 00:00:00 2001 From: Shyam Prasad N Date: Wed, 27 Jul 2022 14:49:56 -0500 Subject: cifs: avoid use of global locks for high contention data During analysis of multichannel perf, it was seen that the global locks cifs_tcp_ses_lock and GlobalMid_Lock, which were shared between various data structures were causing a lot of contention points. With this change, we're breaking down the use of these locks by introducing new locks at more granular levels. i.e. server->srv_lock, ses->ses_lock and tcon->tc_lock to protect the unprotected fields of server, session and tcon structs; and server->mid_lock to protect mid related lists and entries at server level. Signed-off-by: Shyam Prasad N Signed-off-by: Steve French --- fs/cifs/smb1ops.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'fs/cifs/smb1ops.c') diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c index 2e20ee4dab7b..f36b2d2d40ca 100644 --- a/fs/cifs/smb1ops.c +++ b/fs/cifs/smb1ops.c @@ -92,17 +92,17 @@ cifs_find_mid(struct TCP_Server_Info *server, char *buffer) struct smb_hdr *buf = (struct smb_hdr *)buffer; struct mid_q_entry *mid; - spin_lock(&GlobalMid_Lock); + spin_lock(&server->mid_lock); list_for_each_entry(mid, &server->pending_mid_q, qhead) { if (compare_mid(mid->mid, buf) && mid->mid_state == MID_REQUEST_SUBMITTED && le16_to_cpu(mid->command) == buf->Command) { kref_get(&mid->refcount); - spin_unlock(&GlobalMid_Lock); + spin_unlock(&server->mid_lock); return mid; } } - spin_unlock(&GlobalMid_Lock); + spin_unlock(&server->mid_lock); return NULL; } @@ -166,7 +166,7 @@ cifs_get_next_mid(struct TCP_Server_Info *server) __u16 last_mid, cur_mid; bool collision, reconnect = false; - spin_lock(&GlobalMid_Lock); + spin_lock(&server->mid_lock); /* mid is 16 bit only for CIFS/SMB */ cur_mid = (__u16)((server->CurrentMid) & 0xffff); @@ -225,7 +225,7 @@ cifs_get_next_mid(struct TCP_Server_Info *server) } cur_mid++; } - spin_unlock(&GlobalMid_Lock); + spin_unlock(&server->mid_lock); if (reconnect) { cifs_signal_cifsd_for_reconnect(server, false); -- cgit 1.4.1