From 22d842e3efe56402c33b5e6e303bb71ce9bf9334 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 16 Aug 2022 16:53:48 +0300 Subject: [PATCH] net: mscc: ocelot: turn stats_lock into a spinlock ocelot_get_stats64() currently runs unlocked and therefore may collide with ocelot_port_update_stats() which indirectly accesses the same counters. However, ocelot_get_stats64() runs in atomic context, and we cannot simply take the sleepable ocelot->stats_lock mutex. We need to convert it to an atomic spinlock first. Do that as a preparatory change. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/dsa/ocelot/felix_vsc9959.c | 4 ++-- drivers/net/ethernet/mscc/ocelot.c | 11 +++++------ include/soc/mscc/ocelot.h | 2 +- 3 files changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c index e1ebe21..46fd6cd 100644 --- a/drivers/net/dsa/ocelot/felix_vsc9959.c +++ b/drivers/net/dsa/ocelot/felix_vsc9959.c @@ -2171,7 +2171,7 @@ static void vsc9959_psfp_sgi_table_del(struct ocelot *ocelot, static void vsc9959_psfp_counters_get(struct ocelot *ocelot, u32 index, struct felix_stream_filter_counters *counters) { - mutex_lock(&ocelot->stats_lock); + spin_lock(&ocelot->stats_lock); ocelot_rmw(ocelot, SYS_STAT_CFG_STAT_VIEW(index), SYS_STAT_CFG_STAT_VIEW_M, @@ -2188,7 +2188,7 @@ static void vsc9959_psfp_counters_get(struct ocelot *ocelot, u32 index, SYS_STAT_CFG_STAT_CLEAR_SHOT(0x10), SYS_STAT_CFG); - mutex_unlock(&ocelot->stats_lock); + spin_unlock(&ocelot->stats_lock); } static int vsc9959_psfp_filter_add(struct ocelot *ocelot, int port, diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c index d4649e4..c67f162 100644 --- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -1906,13 +1906,13 @@ static void ocelot_check_stats_work(struct work_struct *work) stats_work); int i, err; - mutex_lock(&ocelot->stats_lock); + spin_lock(&ocelot->stats_lock); for (i = 0; i < ocelot->num_phys_ports; i++) { err = ocelot_port_update_stats(ocelot, i); if (err) break; } - mutex_unlock(&ocelot->stats_lock); + spin_unlock(&ocelot->stats_lock); if (err) dev_err(ocelot->dev, "Error %d updating ethtool stats\n", err); @@ -1925,7 +1925,7 @@ void ocelot_get_ethtool_stats(struct ocelot *ocelot, int port, u64 *data) { int i, err; - mutex_lock(&ocelot->stats_lock); + spin_lock(&ocelot->stats_lock); /* check and update now */ err = ocelot_port_update_stats(ocelot, port); @@ -1934,7 +1934,7 @@ void ocelot_get_ethtool_stats(struct ocelot *ocelot, int port, u64 *data) for (i = 0; i < ocelot->num_stats; i++) *data++ = ocelot->stats[port * ocelot->num_stats + i]; - mutex_unlock(&ocelot->stats_lock); + spin_unlock(&ocelot->stats_lock); if (err) dev_err(ocelot->dev, "Error %d updating ethtool stats\n", err); @@ -3363,7 +3363,7 @@ int ocelot_init(struct ocelot *ocelot) if (!ocelot->stats) return -ENOMEM; - mutex_init(&ocelot->stats_lock); + spin_lock_init(&ocelot->stats_lock); mutex_init(&ocelot->ptp_lock); mutex_init(&ocelot->mact_lock); mutex_init(&ocelot->fwd_domain_lock); @@ -3511,7 +3511,6 @@ void ocelot_deinit(struct ocelot *ocelot) cancel_delayed_work(&ocelot->stats_work); destroy_workqueue(ocelot->stats_queue); destroy_workqueue(ocelot->owq); - mutex_destroy(&ocelot->stats_lock); } EXPORT_SYMBOL(ocelot_deinit); diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h index e7e5b06..72b9474 100644 --- a/include/soc/mscc/ocelot.h +++ b/include/soc/mscc/ocelot.h @@ -752,7 +752,7 @@ struct ocelot { struct ocelot_psfp_list psfp; /* Workqueue to check statistics for overflow with its lock */ - struct mutex stats_lock; + spinlock_t stats_lock; u64 *stats; struct delayed_work stats_work; struct workqueue_struct *stats_queue; -- 2.7.4