From: Eric Dumazet <edumazet@google.com>
To: "David S . Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Paolo Abeni <pabeni@redhat.com>
Cc: "Simon Horman" <horms@kernel.org>,
"Jamal Hadi Salim" <jhs@mojatatu.com>,
"Victor Nogueira" <victor@mojatatu.com>,
"Jiri Pirko" <jiri@resnulli.us>,
"Toke Høiland-Jørgensen" <toke@toke.dk>,
netdev@vger.kernel.org, eric.dumazet@gmail.com,
"Eric Dumazet" <edumazet@google.com>,
"Vineet Agarwal" <agarwal.vineet2006@gmail.com>
Subject: [PATCH net-next] net/sched: sch_dualpi2: annotate data-races in dualpi2_dump_stats()
Date: Thu, 14 May 2026 11:47:13 +0000 [thread overview]
Message-ID: <20260514114713.4134674-1-edumazet@google.com> (raw)
dualpi2_dump_stats() runs without qdisc lock held.
Add missing READ_ONCE()/WRITE_ONCE() annotations.
Fixes: d4de8bffbef4 ("sched: Dump configuration and statistics of dualpi2 qdisc")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vineet Agarwal <agarwal.vineet2006@gmail.com>
---
net/sched/sch_dualpi2.c | 68 ++++++++++++++++++++---------------------
1 file changed, 34 insertions(+), 34 deletions(-)
diff --git a/net/sched/sch_dualpi2.c b/net/sched/sch_dualpi2.c
index c6416f09dddd8f170b92e50fb89377a15773c5bf..8b3bc646730499dac1798372ef5b647c2e9e5a57 100644
--- a/net/sched/sch_dualpi2.c
+++ b/net/sched/sch_dualpi2.c
@@ -190,7 +190,7 @@ static bool skb_apply_step(struct sk_buff *skb, struct dualpi2_sched_data *q)
static bool dualpi2_mark(struct dualpi2_sched_data *q, struct sk_buff *skb)
{
if (INET_ECN_set_ce(skb)) {
- q->ecn_mark++;
+ WRITE_ONCE(q->ecn_mark, q->ecn_mark + 1);
return true;
}
return false;
@@ -198,7 +198,7 @@ static bool dualpi2_mark(struct dualpi2_sched_data *q, struct sk_buff *skb)
static void dualpi2_reset_c_protection(struct dualpi2_sched_data *q)
{
- q->c_protection_credit = q->c_protection_init;
+ WRITE_ONCE(q->c_protection_credit, q->c_protection_init);
}
/* This computes the initial credit value and WRR weight for the L queue (wl)
@@ -403,12 +403,12 @@ static int dualpi2_enqueue_skb(struct sk_buff *skb, struct Qdisc *sch,
cb = dualpi2_skb_cb(skb);
cb->ts = ktime_get_ns();
- q->memory_used += skb->truesize;
+ WRITE_ONCE(q->memory_used, q->memory_used + skb->truesize);
if (q->memory_used > q->max_memory_used)
- q->max_memory_used = q->memory_used;
+ WRITE_ONCE(q->max_memory_used, q->memory_used);
if (qdisc_qlen(sch) > q->maxq)
- q->maxq = qdisc_qlen(sch);
+ WRITE_ONCE(q->maxq, qdisc_qlen(sch));
if (skb_in_l_queue(skb)) {
/* Apply step thresh if skb is L4S && L-queue len >= min_qlen */
@@ -417,14 +417,14 @@ static int dualpi2_enqueue_skb(struct sk_buff *skb, struct Qdisc *sch,
/* Keep the overall qdisc stats consistent */
qdisc_qlen_inc(sch);
qdisc_qstats_backlog_inc(sch, skb);
- ++q->packets_in_l;
+ WRITE_ONCE(q->packets_in_l, q->packets_in_l + 1);
if (!q->l_head_ts)
- q->l_head_ts = cb->ts;
+ WRITE_ONCE(q->l_head_ts, cb->ts);
return qdisc_enqueue_tail(skb, q->l_queue);
}
- ++q->packets_in_c;
+ WRITE_ONCE(q->packets_in_c, q->packets_in_c + 1);
if (!q->c_head_ts)
- q->c_head_ts = cb->ts;
+ WRITE_ONCE(q->c_head_ts, cb->ts);
return qdisc_enqueue_tail(skb, sch);
}
@@ -531,17 +531,16 @@ static struct sk_buff *dequeue_packet(struct Qdisc *sch,
/* Keep the global queue size consistent */
qdisc_qlen_dec(sch);
- q->memory_used -= skb->truesize;
} else if (c_len) {
skb = __qdisc_dequeue_head(&sch->q);
WRITE_ONCE(q->c_head_ts, head_enqueue_time(sch));
if (qdisc_qlen(q->l_queue))
*credit_change = ~((s32)q->c_protection_wl) + 1;
- q->memory_used -= skb->truesize;
} else {
dualpi2_reset_c_protection(q);
return NULL;
}
+ WRITE_ONCE(q->memory_used, q->memory_used - skb->truesize);
*credit_change *= qdisc_pkt_len(skb);
qdisc_qstats_backlog_dec(sch, skb);
return skb;
@@ -564,7 +563,7 @@ static int do_step_aqm(struct dualpi2_sched_data *q, struct sk_buff *skb,
}
if (dualpi2_mark(q, skb))
- ++q->step_marks;
+ WRITE_ONCE(q->step_marks, q->step_marks + 1);
}
qdisc_bstats_update(q->l_queue, skb);
return 0;
@@ -600,7 +599,8 @@ static struct sk_buff *dualpi2_qdisc_dequeue(struct Qdisc *sch)
continue;
}
- q->c_protection_credit += credit_change;
+ WRITE_ONCE(q->c_protection_credit,
+ q->c_protection_credit + credit_change);
qdisc_bstats_update(sch, skb);
break;
}
@@ -876,7 +876,7 @@ static int dualpi2_change(struct Qdisc *sch, struct nlattr *opt,
WARN_ON_ONCE(1);
break;
}
- q->memory_used -= skb->truesize;
+ WRITE_ONCE(q->memory_used, q->memory_used - skb->truesize);
rtnl_qdisc_drop(skb, sch);
} else if (qdisc_qlen(q->l_queue)) {
skb = qdisc_dequeue_internal(q->l_queue, true);
@@ -890,7 +890,7 @@ static int dualpi2_change(struct Qdisc *sch, struct nlattr *opt,
*/
qdisc_qlen_dec(sch);
qdisc_qstats_backlog_dec(sch, skb);
- q->memory_used -= skb->truesize;
+ WRITE_ONCE(q->memory_used, q->memory_used - skb->truesize);
rtnl_qdisc_drop(skb, q->l_queue);
qdisc_qstats_drop(sch);
} else {
@@ -1046,15 +1046,15 @@ static int dualpi2_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
struct dualpi2_sched_data *q = qdisc_priv(sch);
struct tc_dualpi2_xstats st = {
.prob = READ_ONCE(q->pi2_prob),
- .packets_in_c = q->packets_in_c,
- .packets_in_l = q->packets_in_l,
- .maxq = q->maxq,
- .ecn_mark = q->ecn_mark,
- .credit = q->c_protection_credit,
- .step_marks = q->step_marks,
- .memory_used = q->memory_used,
- .max_memory_used = q->max_memory_used,
- .memory_limit = q->memory_limit,
+ .packets_in_c = READ_ONCE(q->packets_in_c),
+ .packets_in_l = READ_ONCE(q->packets_in_l),
+ .maxq = READ_ONCE(q->maxq),
+ .ecn_mark = READ_ONCE(q->ecn_mark),
+ .credit = READ_ONCE(q->c_protection_credit),
+ .step_marks = READ_ONCE(q->step_marks),
+ .memory_used = READ_ONCE(q->memory_used),
+ .max_memory_used = READ_ONCE(q->max_memory_used),
+ .memory_limit = READ_ONCE(q->memory_limit),
};
u64 qc, ql;
@@ -1074,16 +1074,16 @@ static void dualpi2_reset(struct Qdisc *sch)
qdisc_reset_queue(sch);
qdisc_reset_queue(q->l_queue);
- q->c_head_ts = 0;
- q->l_head_ts = 0;
- q->pi2_prob = 0;
- q->packets_in_c = 0;
- q->packets_in_l = 0;
- q->maxq = 0;
- q->ecn_mark = 0;
- q->step_marks = 0;
- q->memory_used = 0;
- q->max_memory_used = 0;
+ WRITE_ONCE(q->c_head_ts, 0);
+ WRITE_ONCE(q->l_head_ts, 0);
+ WRITE_ONCE(q->pi2_prob, 0);
+ WRITE_ONCE(q->packets_in_c, 0);
+ WRITE_ONCE(q->packets_in_l, 0);
+ WRITE_ONCE(q->maxq, 0);
+ WRITE_ONCE(q->ecn_mark, 0);
+ WRITE_ONCE(q->step_marks, 0);
+ WRITE_ONCE(q->memory_used, 0);
+ WRITE_ONCE(q->max_memory_used, 0);
dualpi2_reset_c_protection(q);
}
--
2.54.0.563.g4f69b47b94-goog
reply other threads:[~2026-05-14 11:47 UTC|newest]
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