From: Sven Eckelmann Date: Tue, 12 May 2026 17:37:05 +0000 (+0200) Subject: batman-adv: replace non-atomic hardif config fields with (READ|WRITE)_ONCE X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dbb48d9089bd607cbe7d73e795ede0090032eafc;p=thirdparty%2Flinux.git batman-adv: replace non-atomic hardif config fields with (READ|WRITE)_ONCE The hardif configuration values are only accessed as plain loads/stores and do not require full atomic_t semantics. Convert these fields to native integer types and replace their users with READ_ONCE()/WRITE_ONCE() to avoid load/store tearing. Signed-off-by: Sven Eckelmann --- diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index 5628017bee511..df8e64588e1e7 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -1218,7 +1218,7 @@ static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node, inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube; inv_asym_penalty /= neigh_rq_max_cube; tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty; - tq_iface_hop_penalty -= atomic_read(&if_incoming->hop_penalty); + tq_iface_hop_penalty -= READ_ONCE(if_incoming->hop_penalty); /* penalize if the OGM is forwarded on the same interface. WiFi * interfaces and other half duplex devices suffer from throughput diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c index 492058a87682b..ac2932da5472d 100644 --- a/net/batman-adv/bat_v.c +++ b/net/batman-adv/bat_v.c @@ -7,7 +7,6 @@ #include "bat_v.h" #include "main.h" -#include #include #include #include @@ -813,8 +812,8 @@ void batadv_v_hardif_init(struct batadv_hard_iface *hard_iface) /* enable link throughput auto-detection by setting the throughput * override to zero */ - atomic_set(&hard_iface->bat_v.throughput_override, 0); - atomic_set(&hard_iface->bat_v.elp_interval, 500); + WRITE_ONCE(hard_iface->bat_v.throughput_override, 0); + WRITE_ONCE(hard_iface->bat_v.elp_interval, 500); hard_iface->bat_v.aggr_len = 0; skb_queue_head_init(&hard_iface->bat_v.aggr_list); diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c index e207093de79fe..0190fafcbed2d 100644 --- a/net/batman-adv/bat_v_elp.c +++ b/net/batman-adv/bat_v_elp.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -62,7 +63,7 @@ static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface) { unsigned int msecs; - msecs = atomic_read(&hard_iface->bat_v.elp_interval) - BATADV_JITTER; + msecs = READ_ONCE(hard_iface->bat_v.elp_interval) - BATADV_JITTER; msecs += get_random_u32_below(2 * BATADV_JITTER); queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.elp_wq, @@ -98,7 +99,7 @@ static bool batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh, /* if the user specified a customised value for this interface, then * return it directly */ - throughput = atomic_read(&hard_iface->bat_v.throughput_override); + throughput = READ_ONCE(hard_iface->bat_v.throughput_override); if (throughput != 0) { *pthroughput = throughput; return true; @@ -324,7 +325,7 @@ static void batadv_v_elp_periodic_work(struct work_struct *work) elp_packet = (struct batadv_elp_packet *)skb->data; elp_packet->seqno = htonl(atomic_read(&hard_iface->bat_v.elp_seqno)); - elp_interval = atomic_read(&hard_iface->bat_v.elp_interval); + elp_interval = READ_ONCE(hard_iface->bat_v.elp_interval); elp_packet->elp_interval = htonl(elp_interval); batadv_dbg(BATADV_DBG_BATMAN, bat_priv, diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c index 28f28b61ad6bc..f4cd8cad97e0c 100644 --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -486,9 +486,9 @@ static u32 batadv_v_forward_penalty(struct batadv_priv *bat_priv, struct batadv_hard_iface *if_outgoing, u32 throughput) { - int if_hop_penalty = atomic_read(&if_incoming->hop_penalty); - int hop_penalty = READ_ONCE(bat_priv->hop_penalty); - int hop_penalty_max = BATADV_TQ_MAX_VALUE; + u32 if_hop_penalty = READ_ONCE(if_incoming->hop_penalty); + u32 hop_penalty = READ_ONCE(bat_priv->hop_penalty); + u32 hop_penalty_max = BATADV_TQ_MAX_VALUE; /* Apply per hardif hop penalty */ throughput = throughput * (hop_penalty_max - if_hop_penalty) / diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index e89aa4b61a7cd..86e7d10864e2f 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -910,7 +910,7 @@ batadv_hardif_add_interface(struct net_device *net_dev) if (batadv_is_wifi_hardif(hard_iface)) hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; - atomic_set(&hard_iface->hop_penalty, 0); + WRITE_ONCE(hard_iface->hop_penalty, 0); batadv_v_hardif_init(hard_iface); diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c index 027e9fe1042a2..368072f0513c2 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -811,16 +811,16 @@ static int batadv_netlink_hardif_fill(struct sk_buff *msg, } if (nla_put_u8(msg, BATADV_ATTR_HOP_PENALTY, - atomic_read(&hard_iface->hop_penalty))) + READ_ONCE(hard_iface->hop_penalty))) goto nla_put_failure; #ifdef CONFIG_BATMAN_ADV_BATMAN_V if (nla_put_u32(msg, BATADV_ATTR_ELP_INTERVAL, - atomic_read(&hard_iface->bat_v.elp_interval))) + READ_ONCE(hard_iface->bat_v.elp_interval))) goto nla_put_failure; if (nla_put_u32(msg, BATADV_ATTR_THROUGHPUT_OVERRIDE, - atomic_read(&hard_iface->bat_v.throughput_override))) + READ_ONCE(hard_iface->bat_v.throughput_override))) goto nla_put_failure; #endif /* CONFIG_BATMAN_ADV_BATMAN_V */ @@ -913,7 +913,7 @@ static int batadv_netlink_set_hardif(struct sk_buff *skb, if (info->attrs[BATADV_ATTR_HOP_PENALTY]) { attr = info->attrs[BATADV_ATTR_HOP_PENALTY]; - atomic_set(&hard_iface->hop_penalty, nla_get_u8(attr)); + WRITE_ONCE(hard_iface->hop_penalty, nla_get_u8(attr)); } #ifdef CONFIG_BATMAN_ADV_BATMAN_V @@ -921,13 +921,13 @@ static int batadv_netlink_set_hardif(struct sk_buff *skb, if (info->attrs[BATADV_ATTR_ELP_INTERVAL]) { attr = info->attrs[BATADV_ATTR_ELP_INTERVAL]; - atomic_set(&hard_iface->bat_v.elp_interval, nla_get_u32(attr)); + WRITE_ONCE(hard_iface->bat_v.elp_interval, nla_get_u32(attr)); } if (info->attrs[BATADV_ATTR_THROUGHPUT_OVERRIDE]) { attr = info->attrs[BATADV_ATTR_THROUGHPUT_OVERRIDE]; - atomic_set(&hard_iface->bat_v.throughput_override, + WRITE_ONCE(hard_iface->bat_v.throughput_override, nla_get_u32(attr)); } #endif /* CONFIG_BATMAN_ADV_BATMAN_V */ diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index c4845b5e43be0..dd63cd28914d7 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -114,7 +114,7 @@ enum batadv_v_hard_iface_flags { */ struct batadv_hard_iface_bat_v { /** @elp_interval: time interval between two ELP transmissions */ - atomic_t elp_interval; + u32 elp_interval; /** @elp_seqno: current ELP sequence number */ atomic_t elp_seqno; @@ -138,7 +138,7 @@ struct batadv_hard_iface_bat_v { * @throughput_override: throughput override to disable link * auto-detection */ - atomic_t throughput_override; + u32 throughput_override; /** @flags: interface specific flags */ u8 flags; @@ -236,7 +236,7 @@ struct batadv_hard_iface { * @hop_penalty: penalty which will be applied to the tq-field * of an OGM received via this interface */ - atomic_t hop_penalty; + u8 hop_penalty; /** @bat_iv: per hard-interface B.A.T.M.A.N. IV data */ struct batadv_hard_iface_bat_iv bat_iv;