2022-01-28 17:20:21

by Eric Dumazet

[permalink] [raw]
Subject: [PATCH net-next 1/3] SUNRPC: add netns refcount tracker to struct svc_xprt

From: Eric Dumazet <[email protected]>

struct svc_xprt holds a long lived reference to a netns,
it is worth tracking it.

Signed-off-by: Eric Dumazet <[email protected]>
---
include/linux/sunrpc/svc_xprt.h | 1 +
net/sunrpc/svc_xprt.c | 4 ++--
2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
index 571f605bc91ef8fa190e7fd5504efb76ec3fa89e..382af90320acc3a7b3817bf66f65fbb15447ae7d 100644
--- a/include/linux/sunrpc/svc_xprt.h
+++ b/include/linux/sunrpc/svc_xprt.h
@@ -88,6 +88,7 @@ struct svc_xprt {
struct list_head xpt_users; /* callbacks on free */

struct net *xpt_net;
+ netns_tracker ns_tracker;
const struct cred *xpt_cred;
struct rpc_xprt *xpt_bc_xprt; /* NFSv4.1 backchannel */
struct rpc_xprt_switch *xpt_bc_xps; /* NFSv4.1 backchannel */
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index b21ad79941474685597c9c7c07b862ef7e98ad74..db878e833b672864551bc9ef884a3cd6ca6c2603 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -162,7 +162,7 @@ static void svc_xprt_free(struct kref *kref)
if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags))
svcauth_unix_info_release(xprt);
put_cred(xprt->xpt_cred);
- put_net(xprt->xpt_net);
+ put_net_track(xprt->xpt_net, &xprt->ns_tracker);
/* See comment on corresponding get in xs_setup_bc_tcp(): */
if (xprt->xpt_bc_xprt)
xprt_put(xprt->xpt_bc_xprt);
@@ -198,7 +198,7 @@ void svc_xprt_init(struct net *net, struct svc_xprt_class *xcl,
mutex_init(&xprt->xpt_mutex);
spin_lock_init(&xprt->xpt_lock);
set_bit(XPT_BUSY, &xprt->xpt_flags);
- xprt->xpt_net = get_net(net);
+ xprt->xpt_net = get_net_track(net, &xprt->ns_tracker, GFP_ATOMIC);
strcpy(xprt->xpt_remotebuf, "uninitialized");
}
EXPORT_SYMBOL_GPL(svc_xprt_init);
--
2.35.0.rc0.227.g00780c9af4-goog


2022-01-28 17:20:34

by Chuck Lever

[permalink] [raw]
Subject: Re: [PATCH net-next 1/3] SUNRPC: add netns refcount tracker to struct svc_xprt



> On Jan 27, 2022, at 3:09 PM, Eric Dumazet <[email protected]> wrote:
>
> From: Eric Dumazet <[email protected]>
>
> struct svc_xprt holds a long lived reference to a netns,
> it is worth tracking it.
>
> Signed-off-by: Eric Dumazet <[email protected]>

I haven't followed the requirements for the extended tracking,
but I have no objection to this change.

Acked-by: Chuck Lever <[email protected]>


> ---
> include/linux/sunrpc/svc_xprt.h | 1 +
> net/sunrpc/svc_xprt.c | 4 ++--
> 2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
> index 571f605bc91ef8fa190e7fd5504efb76ec3fa89e..382af90320acc3a7b3817bf66f65fbb15447ae7d 100644
> --- a/include/linux/sunrpc/svc_xprt.h
> +++ b/include/linux/sunrpc/svc_xprt.h
> @@ -88,6 +88,7 @@ struct svc_xprt {
> struct list_head xpt_users; /* callbacks on free */
>
> struct net *xpt_net;
> + netns_tracker ns_tracker;
> const struct cred *xpt_cred;
> struct rpc_xprt *xpt_bc_xprt; /* NFSv4.1 backchannel */
> struct rpc_xprt_switch *xpt_bc_xps; /* NFSv4.1 backchannel */
> diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
> index b21ad79941474685597c9c7c07b862ef7e98ad74..db878e833b672864551bc9ef884a3cd6ca6c2603 100644
> --- a/net/sunrpc/svc_xprt.c
> +++ b/net/sunrpc/svc_xprt.c
> @@ -162,7 +162,7 @@ static void svc_xprt_free(struct kref *kref)
> if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags))
> svcauth_unix_info_release(xprt);
> put_cred(xprt->xpt_cred);
> - put_net(xprt->xpt_net);
> + put_net_track(xprt->xpt_net, &xprt->ns_tracker);
> /* See comment on corresponding get in xs_setup_bc_tcp(): */
> if (xprt->xpt_bc_xprt)
> xprt_put(xprt->xpt_bc_xprt);
> @@ -198,7 +198,7 @@ void svc_xprt_init(struct net *net, struct svc_xprt_class *xcl,
> mutex_init(&xprt->xpt_mutex);
> spin_lock_init(&xprt->xpt_lock);
> set_bit(XPT_BUSY, &xprt->xpt_flags);
> - xprt->xpt_net = get_net(net);
> + xprt->xpt_net = get_net_track(net, &xprt->ns_tracker, GFP_ATOMIC);
> strcpy(xprt->xpt_remotebuf, "uninitialized");
> }
> EXPORT_SYMBOL_GPL(svc_xprt_init);
> --
> 2.35.0.rc0.227.g00780c9af4-goog
>

--
Chuck Lever