Commit ffdbc0fe authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'mlxsw-show-per-band-ecn-marked-counter-on-qdisc' 

Ido Schimmel says:

====================
mlxsw: Show per-band ECN-marked counter on qdisc

The RED qdisc can expose number of packets that it has marked through
the prob_marked counter (shown in iproute2 as "marked"). This counter
currently just shows number of packets marked in the SW datapath, which
in a switch deployment likely means zero.

Spectrum-3 does support per-TC counters, and in this patchset, mlxsw
supports this RED statistic properly.
====================

Link: https://lore.kernel.org/r/20211013103748.492531-1-idosch@idosch.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents e79d8264 bf862732

drivers/net/ethernet/mellanox/mlxsw/reg.h

+8 −2
Original line number Diff line number Diff line
@@ -4951,7 +4951,7 @@ enum mlxsw_reg_ppcnt_grp { 
	MLXSW_REG_PPCNT_DISCARD_CNT = 0x6,

	MLXSW_REG_PPCNT_PRIO_CNT = 0x10,

	MLXSW_REG_PPCNT_TC_CNT = 0x11,

	MLXSW_REG_PPCNT_TC_CONG_TC = 0x13,

	MLXSW_REG_PPCNT_TC_CONG_CNT = 0x13,

};



/* reg_ppcnt_grp
@@ -5371,7 +5371,7 @@ MLXSW_ITEM64(reg, ppcnt, tx_pause_duration, 
MLXSW_ITEM64(reg, ppcnt, tx_pause_transition,

	     MLXSW_REG_PPCNT_COUNTERS_OFFSET + 0x70, 0, 64);



/* Ethernet Per Traffic Group Counters */

/* Ethernet Per Traffic Class Counters */



/* reg_ppcnt_tc_transmit_queue

 * Contains the transmit queue depth in cells of traffic class
@@ -5398,6 +5398,12 @@ MLXSW_ITEM64(reg, ppcnt, tc_no_buffer_discard_uc, 
MLXSW_ITEM64(reg, ppcnt, wred_discard,

	     MLXSW_REG_PPCNT_COUNTERS_OFFSET + 0x00, 0, 64);



/* reg_ppcnt_ecn_marked_tc

 * Access: RO

 */

MLXSW_ITEM64(reg, ppcnt, ecn_marked_tc,

	     MLXSW_REG_PPCNT_COUNTERS_OFFSET + 0x08, 0, 64);



static inline void mlxsw_reg_ppcnt_pack(char *payload, u8 local_port,

					enum mlxsw_reg_ppcnt_grp grp,

					u8 prio_tc)

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

+8 −4
Original line number Diff line number Diff line
@@ -824,12 +824,16 @@ mlxsw_sp_port_get_hw_xstats(struct net_device *dev, 


	for (i = 0; i < TC_MAX_QUEUE; i++) {

		err = mlxsw_sp_port_get_stats_raw(dev,

						  MLXSW_REG_PPCNT_TC_CONG_TC,

						  MLXSW_REG_PPCNT_TC_CONG_CNT,

						  i, ppcnt_pl);

		if (!err)

		if (err)

			goto tc_cnt;



		xstats->wred_drop[i] =

			mlxsw_reg_ppcnt_wred_discard_get(ppcnt_pl);

		xstats->tc_ecn[i] = mlxsw_reg_ppcnt_ecn_marked_tc_get(ppcnt_pl);



tc_cnt:

		err = mlxsw_sp_port_get_stats_raw(dev, MLXSW_REG_PPCNT_TC_CNT,

						  i, ppcnt_pl);

		if (err)

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

+1 −0
Original line number Diff line number Diff line
@@ -285,6 +285,7 @@ struct mlxsw_sp_port_vlan { 
/* No need an internal lock; At worse - miss a single periodic iteration */

struct mlxsw_sp_port_xstats {

	u64 ecn;

	u64 tc_ecn[TC_MAX_QUEUE];

	u64 wred_drop[TC_MAX_QUEUE];

	u64 tail_drop[TC_MAX_QUEUE];

	u64 backlog[TC_MAX_QUEUE];

drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c

+7 −2
Original line number Diff line number Diff line
@@ -519,6 +519,7 @@ mlxsw_sp_setup_tc_qdisc_red_clean_stats(struct mlxsw_sp_port *mlxsw_sp_port, 
					       mlxsw_sp_qdisc->prio_bitmap,

					       &stats_base->tx_packets,

					       &stats_base->tx_bytes);

	red_base->prob_mark = xstats->tc_ecn[tclass_num];

	red_base->prob_drop = xstats->wred_drop[tclass_num];

	red_base->pdrop = mlxsw_sp_xstats_tail_drop(xstats, tclass_num);
@@ -618,19 +619,22 @@ mlxsw_sp_qdisc_get_red_xstats(struct mlxsw_sp_port *mlxsw_sp_port, 
	int tclass_num = mlxsw_sp_qdisc->tclass_num;

	struct mlxsw_sp_port_xstats *xstats;

	struct red_stats *res = xstats_ptr;

	int early_drops, pdrops;

	int early_drops, marks, pdrops;



	xstats = &mlxsw_sp_port->periodic_hw_stats.xstats;



	early_drops = xstats->wred_drop[tclass_num] - xstats_base->prob_drop;

	marks = xstats->tc_ecn[tclass_num] - xstats_base->prob_mark;

	pdrops = mlxsw_sp_xstats_tail_drop(xstats, tclass_num) -

		 xstats_base->pdrop;



	res->pdrop += pdrops;

	res->prob_drop += early_drops;

	res->prob_mark += marks;



	xstats_base->pdrop += pdrops;

	xstats_base->prob_drop += early_drops;

	xstats_base->prob_mark += marks;

	return 0;

}
@@ -648,7 +652,8 @@ mlxsw_sp_qdisc_get_red_stats(struct mlxsw_sp_port *mlxsw_sp_port, 
	stats_base = &mlxsw_sp_qdisc->stats_base;



	mlxsw_sp_qdisc_get_tc_stats(mlxsw_sp_port, mlxsw_sp_qdisc, stats_ptr);

	overlimits = xstats->wred_drop[tclass_num] - stats_base->overlimits;

	overlimits = xstats->wred_drop[tclass_num] +

		     xstats->tc_ecn[tclass_num] - stats_base->overlimits;



	stats_ptr->qstats->overlimits += overlimits;

	stats_base->overlimits += overlimits;

tools/testing/selftests/drivers/net/mlxsw/sch_red_core.sh

+41 −10
Original line number Diff line number Diff line
@@ -331,6 +331,14 @@ get_nmarked() 
	ethtool_stats_get $swp3 ecn_marked

}



get_qdisc_nmarked()

{

	local vlan=$1; shift



	busywait_for_counter 1100 +1 \

		qdisc_stats_get $swp3 $(get_qdisc_handle $vlan) .marked

}



get_qdisc_npackets()

{

	local vlan=$1; shift
@@ -384,14 +392,15 @@ build_backlog() 


check_marking()

{

	local get_nmarked=$1; shift

	local vlan=$1; shift

	local cond=$1; shift



	local npackets_0=$(get_qdisc_npackets $vlan)

	local nmarked_0=$(get_nmarked $vlan)

	local nmarked_0=$($get_nmarked $vlan)

	sleep 5

	local npackets_1=$(get_qdisc_npackets $vlan)

	local nmarked_1=$(get_nmarked $vlan)

	local nmarked_1=$($get_nmarked $vlan)



	local nmarked_d=$((nmarked_1 - nmarked_0))

	local npackets_d=$((npackets_1 - npackets_0))
@@ -404,6 +413,7 @@ check_marking() 
ecn_test_common()

{

	local name=$1; shift

	local get_nmarked=$1; shift

	local vlan=$1; shift

	local limit=$1; shift

	local backlog
@@ -416,7 +426,7 @@ ecn_test_common() 
	RET=0

	backlog=$(build_backlog $vlan $((2 * limit / 3)) udp)

	check_err $? "Could not build the requested backlog"

	pct=$(check_marking $vlan "== 0")

	pct=$(check_marking "$get_nmarked" $vlan "== 0")

	check_err $? "backlog $backlog / $limit Got $pct% marked packets, expected == 0."

	log_test "TC $((vlan - 10)): $name backlog < limit"
@@ -426,22 +436,23 @@ ecn_test_common() 
	RET=0

	backlog=$(build_backlog $vlan $((3 * limit / 2)) tcp tos=0x01)

	check_err $? "Could not build the requested backlog"

	pct=$(check_marking $vlan ">= 95")

	pct=$(check_marking "$get_nmarked" $vlan ">= 95")

	check_err $? "backlog $backlog / $limit Got $pct% marked packets, expected >= 95."

	log_test "TC $((vlan - 10)): $name backlog > limit"

}



do_ecn_test()

__do_ecn_test()

{

	local get_nmarked=$1; shift

	local vlan=$1; shift

	local limit=$1; shift

	local name=ECN

	local name=${1-ECN}; shift



	start_tcp_traffic $h1.$vlan $(ipaddr 1 $vlan) $(ipaddr 3 $vlan) \

			  $h3_mac tos=0x01

	sleep 1



	ecn_test_common "$name" $vlan $limit

	ecn_test_common "$name" "$get_nmarked" $vlan $limit



	# Up there we saw that UDP gets accepted when backlog is below the

	# limit. Now that it is above, it should all get dropped, and backlog
@@ -455,6 +466,26 @@ do_ecn_test() 
	sleep 1

}



do_ecn_test()

{

	local vlan=$1; shift

	local limit=$1; shift



	__do_ecn_test get_nmarked "$vlan" "$limit"

}



do_ecn_test_perband()

{

	local vlan=$1; shift

	local limit=$1; shift



	# Per-band ECN counters are not supported on Spectrum-1 and Spectrum-2.

	[[ "$DEVLINK_VIDDID" == "15b3:cb84" ||

	   "$DEVLINK_VIDDID" == "15b3:cf6c" ]] && return



	__do_ecn_test get_qdisc_nmarked "$vlan" "$limit" "per-band ECN"

}



do_ecn_nodrop_test()

{

	local vlan=$1; shift
@@ -465,7 +496,7 @@ do_ecn_nodrop_test() 
			  $h3_mac tos=0x01

	sleep 1



	ecn_test_common "$name" $vlan $limit

	ecn_test_common "$name" get_nmarked $vlan $limit



	# Up there we saw that UDP gets accepted when backlog is below the

	# limit. Now that it is above, in nodrop mode, make sure it goes to
@@ -495,7 +526,7 @@ do_red_test() 
	RET=0

	backlog=$(build_backlog $vlan $((2 * limit / 3)) tcp tos=0x01)

	check_err $? "Could not build the requested backlog"

	pct=$(check_marking $vlan "== 0")

	pct=$(check_marking get_nmarked $vlan "== 0")

	check_err $? "backlog $backlog / $limit Got $pct% marked packets, expected == 0."

	log_test "TC $((vlan - 10)): RED backlog < limit"
@@ -503,7 +534,7 @@ do_red_test() 
	RET=0

	backlog=$(build_backlog $vlan $((3 * limit / 2)) tcp tos=0x01)

	check_fail $? "Traffic went into backlog instead of being early-dropped"

	pct=$(check_marking $vlan "== 0")

	pct=$(check_marking get_nmarked $vlan "== 0")

	check_err $? "backlog $backlog / $limit Got $pct% marked packets, expected == 0."

	local diff=$((limit - backlog))

	pct=$((100 * diff / limit))