svn commit: r277894 - in head: share/man/man4 sys/dev/sfxge

[Andrew Rybchenko]

Author: arybchik
Date: Thu Jan 29 19:09:14 2015
New Revision: 277894
URL: https://svnweb.freebsd.org/changeset/base/277894

Log:
  sfxge: implemented parameter to restrict RSS channels
  
  Submitted by:   Artem V. Andreev <Artem.Andreev at oktetlabs.ru>
  Sponsored by:   Solarflare Communications, Inc.
  Approved by:    gnn (mentor)

Modified:
  head/share/man/man4/sfxge.4
  head/sys/dev/sfxge/sfxge.c
  head/sys/dev/sfxge/sfxge.h
  head/sys/dev/sfxge/sfxge_intr.c

Modified: head/share/man/man4/sfxge.4
==============================================================================
--- head/share/man/man4/sfxge.4	Thu Jan 29 19:06:14 2015	(r277893)
+++ head/share/man/man4/sfxge.4	Thu Jan 29 19:09:14 2015	(r277894)
@@ -108,6 +108,10 @@ If a packet is dropped, the
 .Va tx_early_drops
 counter is incremented and the local sender receives ENOBUFS.
 The value must be greater than or equal to 0.
+.It Va hw.sfxge.N.max_rss_channels
+The maximum number of allocated RSS channels for the Nth adapter.
+If set to 0 or unset, the number of channels is determined by the number
+of CPU cores.
 .El
 .Sh SUPPORT
 For general information and support,

Modified: head/sys/dev/sfxge/sfxge.c
==============================================================================
--- head/sys/dev/sfxge/sfxge.c	Thu Jan 29 19:06:14 2015	(r277893)
+++ head/sys/dev/sfxge/sfxge.c	Thu Jan 29 19:09:14 2015	(r277894)
@@ -397,11 +397,18 @@ sfxge_create(struct sfxge_softc *sc)
 	device_t dev;
 	efx_nic_t *enp;
 	int error;
+	char rss_param_name[sizeof(SFXGE_PARAM(%d.max_rss_channels))];
 
 	dev = sc->dev;
 
 	sx_init(&sc->softc_lock, "sfxge_softc");
 
+	sc->max_rss_channels = 0;
+	snprintf(rss_param_name, sizeof(rss_param_name),
+		 SFXGE_PARAM(%d.max_rss_channels),
+		 (int)device_get_unit(dev));
+	TUNABLE_INT_FETCH(rss_param_name, &sc->max_rss_channels);
+
 	sc->stats_node = SYSCTL_ADD_NODE(
 		device_get_sysctl_ctx(dev),
 		SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),

Modified: head/sys/dev/sfxge/sfxge.h
==============================================================================
--- head/sys/dev/sfxge/sfxge.h	Thu Jan 29 19:06:14 2015	(r277893)
+++ head/sys/dev/sfxge/sfxge.h	Thu Jan 29 19:09:14 2015	(r277894)
@@ -230,6 +230,7 @@ struct sfxge_softc {
 	uint64_t			ev_stats[EV_NQSTATS];
 #endif
 
+	unsigned int			max_rss_channels;
 	uma_zone_t			rxq_cache;
 	struct sfxge_rxq		*rxq[SFXGE_RX_SCALE_MAX];
 	unsigned int			rx_indir_table[SFXGE_RX_SCALE_MAX];

Modified: head/sys/dev/sfxge/sfxge_intr.c
==============================================================================
--- head/sys/dev/sfxge/sfxge_intr.c	Thu Jan 29 19:06:14 2015	(r277893)
+++ head/sys/dev/sfxge/sfxge_intr.c	Thu Jan 29 19:09:14 2015	(r277894)
@@ -302,6 +302,9 @@ sfxge_intr_setup_msix(struct sfxge_softc
 	if (count > EFX_MAXRSS)
 		count = EFX_MAXRSS;
 
+	if (sc->max_rss_channels > 0 && count > sc->max_rss_channels)
+		count = sc->max_rss_channels;
+
 	rid = PCIR_BAR(4);
 	resp = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
 	if (resp == NULL)