MFC r311962

sfxge(4): stats refresh in SW should depend on HW update period

The period should be taken into account by the function which
refreshes driver stats.

Reviewed by:    philip
Sponsored by:   Solarflare Communications, Inc.

3 files changed, 10 insertions, 14 deletions

diff --git a/sys/dev/sfxge/sfxge.c b/sys/dev/sfxge/sfxge.c
index 8b9edb0..e968ef4 100644
--- a/sys/dev/sfxge/sfxge.c
+++ b/sys/dev/sfxge/sfxge.c
@@ -94,14 +94,6 @@ SYSCTL_INT(_hw_sfxge, OID_AUTO, tx_ring, CTLFLAG_RDTUN,
 	   &sfxge_tx_ring_entries, 0,
 	   "Maximum number of descriptors in a transmit ring");
 
-#define	SFXGE_PARAM_STATS_UPDATE_PERIOD	SFXGE_PARAM(stats_update_period)
-static int sfxge_stats_update_period = SFXGE_CALLOUT_TICKS;
-TUNABLE_INT(SFXGE_PARAM_STATS_UPDATE_PERIOD,
-	    &sfxge_stats_update_period);
-SYSCTL_INT(_hw_sfxge, OID_AUTO, stats_update_period, CTLFLAG_RDTUN,
-	   &sfxge_stats_update_period, 0,
-	   "netstat interface statistics update period in ticks");
-
 #define	SFXGE_PARAM_RESTART_ATTEMPTS	SFXGE_PARAM(restart_attempts)
 static int sfxge_restart_attempts = 3;
 TUNABLE_INT(SFXGE_PARAM_RESTART_ATTEMPTS, &sfxge_restart_attempts);
@@ -558,7 +550,7 @@ sfxge_tick(void *arg)
 	sfxge_port_update_stats(sc);
 	sfxge_tx_update_stats(sc);
 
-	callout_reset(&sc->tick_callout, sfxge_stats_update_period,
+	callout_reset(&sc->tick_callout, hz * SFXGE_STATS_UPDATE_PERIOD_MS / 1000,
 		      sfxge_tick, sc);
 }
 
@@ -623,7 +615,7 @@ sfxge_ifnet_init(struct ifnet *ifp, struct sfxge_softc *sc)
 	if ((rc = sfxge_port_ifmedia_init(sc)) != 0)
 		goto fail;
 
-	callout_reset(&sc->tick_callout, sfxge_stats_update_period,
+	callout_reset(&sc->tick_callout, hz * SFXGE_STATS_UPDATE_PERIOD_MS / 1000,
 		      sfxge_tick, sc);
 
 	return (0);
diff --git a/sys/dev/sfxge/sfxge.h b/sys/dev/sfxge/sfxge.h
index 62b1dc3..cc51819 100644
--- a/sys/dev/sfxge/sfxge.h
+++ b/sys/dev/sfxge/sfxge.h
@@ -158,7 +158,7 @@ enum sfxge_evq_state {
 
 #define	SFXGE_EV_BATCH	16384
 
-#define	SFXGE_CALLOUT_TICKS 100
+#define	SFXGE_STATS_UPDATE_PERIOD_MS	1000
 
 struct sfxge_evq {
 	/* Structure members below are sorted by usage order */
diff --git a/sys/dev/sfxge/sfxge_port.c b/sys/dev/sfxge/sfxge_port.c
index 6e753a2..d966150 100644
--- a/sys/dev/sfxge/sfxge_port.c
+++ b/sys/dev/sfxge/sfxge_port.c
@@ -51,6 +51,7 @@ sfxge_mac_stat_update(struct sfxge_softc *sc)
 	struct sfxge_port *port = &sc->port;
 	efsys_mem_t *esmp = &(port->mac_stats.dma_buf);
 	clock_t now;
+	unsigned int min_ticks;
 	unsigned int count;
 	int rc;
 
@@ -61,8 +62,10 @@ sfxge_mac_stat_update(struct sfxge_softc *sc)
 		goto out;
 	}
 
+	min_ticks = (unsigned int)hz * SFXGE_STATS_UPDATE_PERIOD_MS / 1000;
+
 	now = ticks;
-	if ((unsigned int)(now - port->mac_stats.update_time) < (unsigned int)hz) {
+	if ((unsigned int)(now - port->mac_stats.update_time) < min_ticks) {
 		rc = 0;
 		goto out;
 	}
@@ -483,9 +486,10 @@ sfxge_port_start(struct sfxge_softc *sc)
 
 	sfxge_mac_filter_set_locked(sc);
 
-	/* Update MAC stats by DMA every second */
+	/* Update MAC stats by DMA every period */
 	if ((rc = efx_mac_stats_periodic(enp, &port->mac_stats.dma_buf,
-					 1000, B_FALSE)) != 0)
+					 SFXGE_STATS_UPDATE_PERIOD_MS,
+					 B_FALSE)) != 0)
 		goto fail6;
 
 	if ((rc = efx_mac_drain(enp, B_FALSE)) != 0)