svcrpc: make svc_age_temp_xprts enqueue under sv_lock (e75bafbf) · Commits · 戴 / test

svc_age_temp_xprts expires xprts in a two-step process: first it takes the sv_lock and moves the xprts to expire off their server-wide list (sv_tempsocks or sv_permsocks) to a local list. Then it drops the sv_lock and enqueues and puts each one. I see no reason for this: svc_xprt_enqueue() will take sp_lock, but the sv_lock and sp_lock are not otherwise nested anywhere (and documentation at the top of this file claims it's correct to nest these with sp_lock inside.) Cc: stable@kernel.org Tested-by:

Jason Tibbitts <tibbs@math.uh.edu> Tested-by:

Paweł Sikora <pawel.sikora@agmk.net> Signed-off-by:

J. Bruce Fields <bfields@redhat.com>

net/sunrpc/svc_xprt.c

+2 −13

Original line number	Diff line number	Diff line
		@@ -863,7 +863,6 @@ static void svc_age_temp_xprts(unsigned long closure)
		struct svc_serv serv = (struct svc_serv )closure;
		struct svc_xprt *xprt;
		struct list_head le, next;
		LIST_HEAD(to_be_aged);

		dprintk("svc_age_temp_xprts\n");

		@@ -884,25 +883,15 @@ static void svc_age_temp_xprts(unsigned long closure)
		if (atomic_read(&xprt->xpt_ref.refcount) > 1 \|\|
		test_bit(XPT_BUSY, &xprt->xpt_flags))
		continue;
		svc_xprt_get(xprt);
		list_move(le, &to_be_aged);
		list_del_init(le);
		set_bit(XPT_CLOSE, &xprt->xpt_flags);
		set_bit(XPT_DETACHED, &xprt->xpt_flags);
		}
		spin_unlock_bh(&serv->sv_lock);

		while (!list_empty(&to_be_aged)) {
		le = to_be_aged.next;
		/* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */
		list_del_init(le);
		xprt = list_entry(le, struct svc_xprt, xpt_list);

		dprintk("queuing xprt %p for closing\n", xprt);

		/* a thread will dequeue and close it soon */
		svc_xprt_enqueue(xprt);
		svc_xprt_put(xprt);
		}
		spin_unlock_bh(&serv->sv_lock);

		mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
		}

Admin message