From: Paolo Abeni <pabeni@redhat.com>
Date: Thu, 28 Mar 2019 16:53:12 +0100
Subject: net: sched: introduce and use qstats read helpers
Patch-mainline: v5.1-rc4
Git-commit: 5dd431b6b92c0db324d134d2a4006dd4f87f2261
References: bsc#1109837
Classful qdiscs can't access directly the child qdiscs backlog
length: if such qdisc is NOLOCK, per CPU values should be
accounted instead.
Most qdiscs no not respect the above. As a result, qstats fetching
for most classful qdisc is currently incorrect: if the child qdisc is
NOLOCK, it always reports 0 len backlog.
This change introduces a pair of helpers to safely fetch
both backlog and qlen and use them in stats class dumping
functions, fixing the above issue and cleaning a bit the code.
DRR needs also to access the child qdisc queue length, so it
needs custom handling.
Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/net/sch_generic.h | 18 ++++++++++++++++++
net/sched/sch_cbq.c | 4 +++-
net/sched/sch_drr.c | 5 +++--
net/sched/sch_hfsc.c | 5 +++--
net/sched/sch_htb.c | 7 +++----
net/sched/sch_mq.c | 2 +-
net/sched/sch_mqprio.c | 3 +--
net/sched/sch_multiq.c | 2 +-
net/sched/sch_prio.c | 2 +-
net/sched/sch_qfq.c | 3 +--
10 files changed, 35 insertions(+), 16 deletions(-)
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -828,6 +828,24 @@ static inline void qdisc_qstats_overlimi
sch->qstats.overlimits++;
}
+static inline int qdisc_qstats_copy(struct gnet_dump *d, struct Qdisc *sch)
+{
+ __u32 qlen = qdisc_qlen_sum(sch);
+
+ return gnet_stats_copy_queue(d, sch->cpu_qstats, &sch->qstats, qlen);
+}
+
+static inline void qdisc_qstats_qlen_backlog(struct Qdisc *sch, __u32 *qlen,
+ __u32 *backlog)
+{
+ struct gnet_stats_queue qstats = { 0 };
+ __u32 len = qdisc_qlen_sum(sch);
+
+ __gnet_stats_copy_queue(&qstats, sch->cpu_qstats, &sch->qstats, len);
+ *qlen = qstats.qlen;
+ *backlog = qstats.backlog;
+}
+
static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
{
qh->head = NULL;
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1358,9 +1358,11 @@ cbq_dump_class_stats(struct Qdisc *sch,
{
struct cbq_sched_data *q = qdisc_priv(sch);
struct cbq_class *cl = (struct cbq_class *)arg;
+ __u32 qlen;
cl->xstats.avgidle = cl->avgidle;
cl->xstats.undertime = 0;
+ qdisc_qstats_qlen_backlog(cl->q, &qlen, &cl->qstats.backlog);
if (cl->undertime != PSCHED_PASTPERFECT)
cl->xstats.undertime = cl->undertime - q->now;
@@ -1368,7 +1370,7 @@ cbq_dump_class_stats(struct Qdisc *sch,
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
d, NULL, &cl->bstats) < 0 ||
gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
- gnet_stats_copy_queue(d, NULL, &cl->qstats, cl->q->q.qlen) < 0)
+ gnet_stats_copy_queue(d, NULL, &cl->qstats, qlen) < 0)
return -1;
return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats));
--- a/net/sched/sch_drr.c
+++ b/net/sched/sch_drr.c
@@ -269,7 +269,8 @@ static int drr_dump_class_stats(struct Q
struct gnet_dump *d)
{
struct drr_class *cl = (struct drr_class *)arg;
- __u32 qlen = cl->qdisc->q.qlen;
+ __u32 qlen = qdisc_qlen_sum(cl->qdisc);
+ struct Qdisc *cl_q = cl->qdisc;
struct tc_drr_stats xstats;
memset(&xstats, 0, sizeof(xstats));
@@ -279,7 +280,7 @@ static int drr_dump_class_stats(struct Q
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
d, NULL, &cl->bstats) < 0 ||
gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
- gnet_stats_copy_queue(d, NULL, &cl->qdisc->qstats, qlen) < 0)
+ gnet_stats_copy_queue(d, cl_q->cpu_qstats, &cl_q->qstats, qlen) < 0)
return -1;
return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1328,8 +1328,9 @@ hfsc_dump_class_stats(struct Qdisc *sch,
{
struct hfsc_class *cl = (struct hfsc_class *)arg;
struct tc_hfsc_stats xstats;
+ __u32 qlen;
- cl->qstats.backlog = cl->qdisc->qstats.backlog;
+ qdisc_qstats_qlen_backlog(cl->qdisc, &qlen, &cl->qstats.backlog);
xstats.level = cl->level;
xstats.period = cl->cl_vtperiod;
xstats.work = cl->cl_total;
@@ -1337,7 +1338,7 @@ hfsc_dump_class_stats(struct Qdisc *sch,
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch), d, NULL, &cl->bstats) < 0 ||
gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
- gnet_stats_copy_queue(d, NULL, &cl->qstats, cl->qdisc->q.qlen) < 0)
+ gnet_stats_copy_queue(d, NULL, &cl->qstats, qlen) < 0)
return -1;
return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1127,10 +1127,9 @@ htb_dump_class_stats(struct Qdisc *sch,
};
__u32 qlen = 0;
- if (!cl->level && cl->leaf.q) {
- qlen = cl->leaf.q->q.qlen;
- qs.backlog = cl->leaf.q->qstats.backlog;
- }
+ if (!cl->level && cl->leaf.q)
+ qdisc_qstats_qlen_backlog(cl->leaf.q, &qlen, &qs.backlog);
+
cl->xstats.tokens = clamp_t(s64, PSCHED_NS2TICKS(cl->tokens),
INT_MIN, INT_MAX);
cl->xstats.ctokens = clamp_t(s64, PSCHED_NS2TICKS(cl->ctokens),
--- a/net/sched/sch_mq.c
+++ b/net/sched/sch_mq.c
@@ -243,7 +243,7 @@ static int mq_dump_class_stats(struct Qd
sch = dev_queue->qdisc_sleeping;
if (gnet_stats_copy_basic(&sch->running, d, NULL, &sch->bstats) < 0 ||
- gnet_stats_copy_queue(d, NULL, &sch->qstats, sch->q.qlen) < 0)
+ qdisc_qstats_copy(d, sch) < 0)
return -1;
return 0;
}
--- a/net/sched/sch_mqprio.c
+++ b/net/sched/sch_mqprio.c
@@ -561,8 +561,7 @@ static int mqprio_dump_class_stats(struc
sch = dev_queue->qdisc_sleeping;
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
d, NULL, &sch->bstats) < 0 ||
- gnet_stats_copy_queue(d, NULL,
- &sch->qstats, sch->q.qlen) < 0)
+ qdisc_qstats_copy(d, sch) < 0)
return -1;
}
return 0;
--- a/net/sched/sch_multiq.c
+++ b/net/sched/sch_multiq.c
@@ -344,7 +344,7 @@ static int multiq_dump_class_stats(struc
cl_q = q->queues[cl - 1];
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
d, NULL, &cl_q->bstats) < 0 ||
- gnet_stats_copy_queue(d, NULL, &cl_q->qstats, cl_q->q.qlen) < 0)
+ qdisc_qstats_copy(d, cl_q) < 0)
return -1;
return 0;
--- a/net/sched/sch_prio.c
+++ b/net/sched/sch_prio.c
@@ -400,7 +400,7 @@ static int prio_dump_class_stats(struct
cl_q = q->queues[cl - 1];
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
d, NULL, &cl_q->bstats) < 0 ||
- gnet_stats_copy_queue(d, NULL, &cl_q->qstats, cl_q->q.qlen) < 0)
+ qdisc_qstats_copy(d, cl_q) < 0)
return -1;
return 0;
--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -655,8 +655,7 @@ static int qfq_dump_class_stats(struct Q
if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
d, NULL, &cl->bstats) < 0 ||
gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
- gnet_stats_copy_queue(d, NULL,
- &cl->qdisc->qstats, cl->qdisc->q.qlen) < 0)
+ qdisc_qstats_copy(d, cl->qdisc) < 0)
return -1;
return gnet_stats_copy_app(d, &xstats, sizeof(xstats));