diff mbox series

[RFC,4/6] ceph: don't take s_mutex in try_flush_caps

Message ID 20210615145730.21952-5-jlayton@kernel.org
State New
Headers show
Series [RFC,1/6] ceph: allow ceph_put_mds_session to take NULL or ERR_PTR | expand

Commit Message

Jeff Layton June 15, 2021, 2:57 p.m. UTC
The s_mutex doesn't protect anything in this codepath.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/ceph/caps.c | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

Comments

Luis Henriques June 16, 2021, 3:25 p.m. UTC | #1
On Tue, Jun 15, 2021 at 10:57:28AM -0400, Jeff Layton wrote:
> The s_mutex doesn't protect anything in this codepath.

> 

> Signed-off-by: Jeff Layton <jlayton@kernel.org>

> ---

>  fs/ceph/caps.c | 16 ++--------------

>  1 file changed, 2 insertions(+), 14 deletions(-)

> 

> diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c

> index 825b1e463ad3..d21b1fa36875 100644

> --- a/fs/ceph/caps.c

> +++ b/fs/ceph/caps.c

> @@ -2149,26 +2149,17 @@ static int try_flush_caps(struct inode *inode, u64 *ptid)

>  {

>  	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;

>  	struct ceph_inode_info *ci = ceph_inode(inode);

> -	struct ceph_mds_session *session = NULL;

>  	int flushing = 0;

>  	u64 flush_tid = 0, oldest_flush_tid = 0;

>  

> -retry:

>  	spin_lock(&ci->i_ceph_lock);

>  retry_locked:

>  	if (ci->i_dirty_caps && ci->i_auth_cap) {

>  		struct ceph_cap *cap = ci->i_auth_cap;

>  		struct cap_msg_args arg;

> +		struct ceph_mds_session *session = cap->session;

>  

> -		if (session != cap->session) {

> -			spin_unlock(&ci->i_ceph_lock);

> -			if (session)

> -				mutex_unlock(&session->s_mutex);

> -			session = cap->session;

> -			mutex_lock(&session->s_mutex);

> -			goto retry;

> -		}

> -		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN) {

> +		if (session->s_state < CEPH_MDS_SESSION_OPEN) {

>  			spin_unlock(&ci->i_ceph_lock);

>  			goto out;

>  		}

> @@ -2205,9 +2196,6 @@ static int try_flush_caps(struct inode *inode, u64 *ptid)

>  		spin_unlock(&ci->i_ceph_lock);

>  	}

>  out:

> -	if (session)

> -		mutex_unlock(&session->s_mutex);

> -

>  	*ptid = flush_tid;

>  	return flushing;

>  }

> -- 

> 2.31.1

> 


Reviewed-by: Luis Henriques <lhenriques@suse.de>


Cheers,
--
Luís
diff mbox series

Patch

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 825b1e463ad3..d21b1fa36875 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -2149,26 +2149,17 @@  static int try_flush_caps(struct inode *inode, u64 *ptid)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 	struct ceph_inode_info *ci = ceph_inode(inode);
-	struct ceph_mds_session *session = NULL;
 	int flushing = 0;
 	u64 flush_tid = 0, oldest_flush_tid = 0;
 
-retry:
 	spin_lock(&ci->i_ceph_lock);
 retry_locked:
 	if (ci->i_dirty_caps && ci->i_auth_cap) {
 		struct ceph_cap *cap = ci->i_auth_cap;
 		struct cap_msg_args arg;
+		struct ceph_mds_session *session = cap->session;
 
-		if (session != cap->session) {
-			spin_unlock(&ci->i_ceph_lock);
-			if (session)
-				mutex_unlock(&session->s_mutex);
-			session = cap->session;
-			mutex_lock(&session->s_mutex);
-			goto retry;
-		}
-		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN) {
+		if (session->s_state < CEPH_MDS_SESSION_OPEN) {
 			spin_unlock(&ci->i_ceph_lock);
 			goto out;
 		}
@@ -2205,9 +2196,6 @@  static int try_flush_caps(struct inode *inode, u64 *ptid)
 		spin_unlock(&ci->i_ceph_lock);
 	}
 out:
-	if (session)
-		mutex_unlock(&session->s_mutex);
-
 	*ptid = flush_tid;
 	return flushing;
 }