diff mbox series

cifs: add missing spinlock around tcon refcount

Message ID 20220914043451.18797-1-pc@cjr.nz (mailing list archive)
State New, archived
Headers show
Series cifs: add missing spinlock around tcon refcount | expand

Commit Message

Paulo Alcantara Sept. 14, 2022, 4:34 a.m. UTC
Add missing spinlock to protect updates on tcon refcount in
cifs_put_tcon().

Fixes: d7d7a66aacd6 ("cifs: avoid use of global locks for high contention data")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
---
 fs/cifs/connect.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

ronnie sahlberg Sept. 14, 2022, 5:28 a.m. UTC | #1
LGTM

On Wed, 14 Sept 2022 at 14:47, Paulo Alcantara <pc@cjr.nz> wrote:
>
> Add missing spinlock to protect updates on tcon refcount in
> cifs_put_tcon().
>
> Fixes: d7d7a66aacd6 ("cifs: avoid use of global locks for high contention data")
> Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
> ---
>  fs/cifs/connect.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> index 251753d0a54b..23fc48aa2ed6 100644
> --- a/fs/cifs/connect.c
> +++ b/fs/cifs/connect.c
> @@ -2350,7 +2350,9 @@ cifs_put_tcon(struct cifs_tcon *tcon)
>         ses = tcon->ses;
>         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
>         spin_lock(&cifs_tcp_ses_lock);
> +       spin_lock(&tcon->tc_lock);
>         if (--tcon->tc_count > 0) {
> +               spin_unlock(&tcon->tc_lock);
>                 spin_unlock(&cifs_tcp_ses_lock);
>                 return;
>         }
> @@ -2359,6 +2361,7 @@ cifs_put_tcon(struct cifs_tcon *tcon)
>         WARN_ON(tcon->tc_count < 0);
>
>         list_del_init(&tcon->tcon_list);
> +       spin_unlock(&tcon->tc_lock);
>         spin_unlock(&cifs_tcp_ses_lock);
>
>         /* cancel polling of interfaces */
> --
> 2.37.3
>
diff mbox series

Patch

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 251753d0a54b..23fc48aa2ed6 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2350,7 +2350,9 @@  cifs_put_tcon(struct cifs_tcon *tcon)
 	ses = tcon->ses;
 	cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
 	spin_lock(&cifs_tcp_ses_lock);
+	spin_lock(&tcon->tc_lock);
 	if (--tcon->tc_count > 0) {
+		spin_unlock(&tcon->tc_lock);
 		spin_unlock(&cifs_tcp_ses_lock);
 		return;
 	}
@@ -2359,6 +2361,7 @@  cifs_put_tcon(struct cifs_tcon *tcon)
 	WARN_ON(tcon->tc_count < 0);
 
 	list_del_init(&tcon->tcon_list);
+	spin_unlock(&tcon->tc_lock);
 	spin_unlock(&cifs_tcp_ses_lock);
 
 	/* cancel polling of interfaces */