Rather than fix questionable ifnet list locking in the implementation of

the kern.polling.enable sysctl, remove the sysctl.  It has been deprecated
since FreeBSD 6 in favour of per-ifnet polling flags.

Reviewed by:	luigi
Approved by:	re (kib)

2 files changed, 10 insertions, 58 deletions

diff --git a/share/man/man4/polling.4 b/share/man/man4/polling.4
index fea0bfb..2c711cc 100644
--- a/share/man/man4/polling.4
+++ b/share/man/man4/polling.4
@@ -87,6 +87,16 @@ feature.
 It is turned on and off with help of
 .Xr ifconfig 8
 command.
+.Pp
+The historic
+.Va kern.polling.enable ,
+which enabled polling for all interfaces, can be replaced with the following
+code:
+.Bd -literal
+for i in `ifconfig -l` ;
+  do ifconfig $i polling; # use -polling to disable
+done
+.Ed
 .Ss MIB Variables
 The operation of
 .Nm
@@ -156,15 +166,6 @@ Default is 20.
 How many active devices have registered for
 .Nm .
 .Pp
-.It Va kern.polling.enable
-Legacy MIB, that was used to enable or disable polling globally.
-Currently if set to 1,
-.Nm
-is enabled on all capable interfaces.
-If set to 0,
-.Nm
-is disabled on all interfaces.
-.Pp
 .It Va kern.polling.short_ticks
 .It Va kern.polling.lost_polls
 .It Va kern.polling.pending_polls
diff --git a/sys/kern/kern_poll.c b/sys/kern/kern_poll.c
index 5df26bb..8441126 100644
--- a/sys/kern/kern_poll.c
+++ b/sys/kern/kern_poll.c
@@ -46,8 +46,6 @@ __FBSDID("$FreeBSD$");
 #include <net/netisr.h>			/* for NETISR_POLL		*/
 #include <net/vnet.h>
 
-static int poll_switch(SYSCTL_HANDLER_ARGS);
-
 void hardclock_device_poll(void);	/* hook from hardclock		*/
 
 static struct mtx	poll_mtx;
@@ -230,10 +228,6 @@ static uint32_t poll_handlers; /* next free entry in pr[]. */
 SYSCTL_UINT(_kern_polling, OID_AUTO, handlers, CTLFLAG_RD,
 	&poll_handlers, 0, "Number of registered poll handlers");
 
-static int polling = 0;
-SYSCTL_PROC(_kern_polling, OID_AUTO, enable, CTLTYPE_UINT | CTLFLAG_RW,
-	0, sizeof(int), poll_switch, "I", "Switch polling for all interfaces");
-
 static uint32_t phase;
 SYSCTL_UINT(_kern_polling, OID_AUTO, phase, CTLFLAG_RD,
 	&phase, 0, "Polling phase");
@@ -538,49 +532,6 @@ ether_poll_deregister(struct ifnet *ifp)
 	return (0);
 }
 
-/*
- * Legacy interface for turning polling on all interfaces at one time.
- */
-static int
-poll_switch(SYSCTL_HANDLER_ARGS)
-{
-	struct ifnet *ifp;
-	int error;
-	int val = polling;
-
-	error = sysctl_handle_int(oidp, &val, 0, req);
-	if (error || !req->newptr )
-		return (error);
-
-	if (val == polling)
-		return (0);
-
-	if (val < 0 || val > 1)
-		return (EINVAL);
-
-	polling = val;
-
-	IFNET_RLOCK();
-	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
-		if (ifp->if_capabilities & IFCAP_POLLING) {
-			struct ifreq ifr;
-
-			if (val == 1)
-				ifr.ifr_reqcap =
-				    ifp->if_capenable | IFCAP_POLLING;
-			else
-				ifr.ifr_reqcap =
-				    ifp->if_capenable & ~IFCAP_POLLING;
-			(void) (*ifp->if_ioctl)(ifp, SIOCSIFCAP, (caddr_t)&ifr);
-		}
-	}
-	IFNET_RUNLOCK();
-
-	log(LOG_ERR, "kern.polling.enable is deprecated. Use ifconfig(8)");
-
-	return (0);
-}
-
 static void
 poll_idle(void)
 {