From 377cda13a25513f714ea5b5a765408292ca4627a Mon Sep 17 00:00:00 2001 From: Andrew Lunn Date: Thu, 15 Feb 2018 14:38:34 +0100 Subject: [PATCH 1/2] net: dsa: mv88e6xxx: Release mutex between each statistics read The PTP code needs low latency access to the PTP hardware timestamps. Reading all the statistics in one go adds a lot of latency to the PTP code. So take and release the reg_lock mutex for each individual statistics, allowing the PTP thread jump in between. Signed-off-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/dsa/mv88e6xxx/chip.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c index af63710e93c1..bd5cb8a0330e 100644 --- a/drivers/net/dsa/mv88e6xxx/chip.c +++ b/drivers/net/dsa/mv88e6xxx/chip.c @@ -714,9 +714,12 @@ static void mv88e6xxx_stats_get_stats(struct mv88e6xxx_chip *chip, int port, for (i = 0, j = 0; i < ARRAY_SIZE(mv88e6xxx_hw_stats); i++) { stat = &mv88e6xxx_hw_stats[i]; if (stat->type & types) { + mutex_lock(&chip->reg_lock); data[j] = _mv88e6xxx_get_ethtool_stat(chip, stat, port, bank1_select, histogram); + mutex_unlock(&chip->reg_lock); + j++; } } @@ -764,14 +767,13 @@ static void mv88e6xxx_get_ethtool_stats(struct dsa_switch *ds, int port, mutex_lock(&chip->reg_lock); ret = mv88e6xxx_stats_snapshot(chip, port); - if (ret < 0) { - mutex_unlock(&chip->reg_lock); + mutex_unlock(&chip->reg_lock); + + if (ret < 0) return; - } mv88e6xxx_get_stats(chip, port, data); - mutex_unlock(&chip->reg_lock); } static int mv88e6xxx_stats_set_histogram(struct mv88e6xxx_chip *chip) From a61e54063423e9e8d604ea54e6664433946fe6af Mon Sep 17 00:00:00 2001 From: Andrew Lunn Date: Thu, 15 Feb 2018 14:38:35 +0100 Subject: [PATCH 2/2] net: dsa: mv88e6xxx: Release mutex between each ATU read The PTP code needs low latency access to the PTP hardware timestamps. Reading all the ATU entries in one go adds a lot of latency to the PTP code. So take and release the reg_lock mutex for each individual MAC address in the ATU, allowing the PTP thread jump in between. Signed-off-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/dsa/mv88e6xxx/chip.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c index bd5cb8a0330e..39c7ad7e490f 100644 --- a/drivers/net/dsa/mv88e6xxx/chip.c +++ b/drivers/net/dsa/mv88e6xxx/chip.c @@ -1437,7 +1437,9 @@ static int mv88e6xxx_port_db_dump_fid(struct mv88e6xxx_chip *chip, eth_broadcast_addr(addr.mac); do { + mutex_lock(&chip->reg_lock); err = mv88e6xxx_g1_atu_getnext(chip, fid, &addr); + mutex_unlock(&chip->reg_lock); if (err) return err; @@ -1470,7 +1472,10 @@ static int mv88e6xxx_port_db_dump(struct mv88e6xxx_chip *chip, int port, int err; /* Dump port's default Filtering Information Database (VLAN ID 0) */ + mutex_lock(&chip->reg_lock); err = mv88e6xxx_port_get_fid(chip, port, &fid); + mutex_unlock(&chip->reg_lock); + if (err) return err; @@ -1480,7 +1485,9 @@ static int mv88e6xxx_port_db_dump(struct mv88e6xxx_chip *chip, int port, /* Dump VLANs' Filtering Information Databases */ do { + mutex_lock(&chip->reg_lock); err = mv88e6xxx_vtu_getnext(chip, &vlan); + mutex_unlock(&chip->reg_lock); if (err) return err; @@ -1500,13 +1507,8 @@ static int mv88e6xxx_port_fdb_dump(struct dsa_switch *ds, int port, dsa_fdb_dump_cb_t *cb, void *data) { struct mv88e6xxx_chip *chip = ds->priv; - int err; - mutex_lock(&chip->reg_lock); - err = mv88e6xxx_port_db_dump(chip, port, cb, data); - mutex_unlock(&chip->reg_lock); - - return err; + return mv88e6xxx_port_db_dump(chip, port, cb, data); } static int mv88e6xxx_bridge_map(struct mv88e6xxx_chip *chip,