gen_stats: Add instead Set the value in __gnet_stats_copy_basic().
authorSebastian Andrzej Siewior <bigeasy@linutronix.de>
Sat, 16 Oct 2021 08:49:02 +0000 (10:49 +0200)
committerDavid S. Miller <davem@davemloft.net>
Mon, 18 Oct 2021 11:54:40 +0000 (12:54 +0100)
__gnet_stats_copy_basic() always assigns the value to the bstats
argument overwriting the previous value. The later added per-CPU version
always accumulated the values in the returning gnet_stats_basic_packed
argument.

Based on review there are five users of that function as of today:
- est_fetch_counters(), ___gnet_stats_copy_basic()
  memsets() bstats to zero, single invocation.

- mq_dump(), mqprio_dump(), mqprio_dump_class_stats()
  memsets() bstats to zero, multiple invocation but does not use the
  function due to !qdisc_is_percpu_stats().

Add the values in __gnet_stats_copy_basic() instead overwriting. Rename
the function to gnet_stats_add_basic() to make it more obvious.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/gen_stats.h
net/core/gen_estimator.c
net/core/gen_stats.c
net/sched/sch_mq.c
net/sched/sch_mqprio.c

index 1424e02cef90c0139a175933577f1b8537bce51a..25740d004bdb06e90863a52f8361724249004d0f 100644 (file)
@@ -46,10 +46,10 @@ int gnet_stats_copy_basic(const seqcount_t *running,
                          struct gnet_dump *d,
                          struct gnet_stats_basic_cpu __percpu *cpu,
                          struct gnet_stats_basic_packed *b);
-void __gnet_stats_copy_basic(const seqcount_t *running,
-                            struct gnet_stats_basic_packed *bstats,
-                            struct gnet_stats_basic_cpu __percpu *cpu,
-                            struct gnet_stats_basic_packed *b);
+void gnet_stats_add_basic(const seqcount_t *running,
+                         struct gnet_stats_basic_packed *bstats,
+                         struct gnet_stats_basic_cpu __percpu *cpu,
+                         struct gnet_stats_basic_packed *b);
 int gnet_stats_copy_basic_hw(const seqcount_t *running,
                             struct gnet_dump *d,
                             struct gnet_stats_basic_cpu __percpu *cpu,
index 8e582e29a41e39809cc534865bb3c91c05b3d9f2..205df8b5116e58c0384791a0c92fb46c7c17e391 100644 (file)
@@ -66,7 +66,7 @@ static void est_fetch_counters(struct net_rate_estimator *e,
        if (e->stats_lock)
                spin_lock(e->stats_lock);
 
-       __gnet_stats_copy_basic(e->running, b, e->cpu_bstats, e->bstats);
+       gnet_stats_add_basic(e->running, b, e->cpu_bstats, e->bstats);
 
        if (e->stats_lock)
                spin_unlock(e->stats_lock);
index e491b083b34854b62fb1e59e1275b1335c779ab4..25d7c0989b83fe4d09e624c1cae373cbd4bcdc2d 100644 (file)
@@ -114,9 +114,8 @@ gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,
 }
 EXPORT_SYMBOL(gnet_stats_start_copy);
 
-static void
-__gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
-                           struct gnet_stats_basic_cpu __percpu *cpu)
+static void gnet_stats_add_basic_cpu(struct gnet_stats_basic_packed *bstats,
+                                    struct gnet_stats_basic_cpu __percpu *cpu)
 {
        int i;
 
@@ -136,26 +135,30 @@ __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
        }
 }
 
-void
-__gnet_stats_copy_basic(const seqcount_t *running,
-                       struct gnet_stats_basic_packed *bstats,
-                       struct gnet_stats_basic_cpu __percpu *cpu,
-                       struct gnet_stats_basic_packed *b)
+void gnet_stats_add_basic(const seqcount_t *running,
+                         struct gnet_stats_basic_packed *bstats,
+                         struct gnet_stats_basic_cpu __percpu *cpu,
+                         struct gnet_stats_basic_packed *b)
 {
        unsigned int seq;
+       u64 bytes = 0;
+       u64 packets = 0;
 
        if (cpu) {
-               __gnet_stats_copy_basic_cpu(bstats, cpu);
+               gnet_stats_add_basic_cpu(bstats, cpu);
                return;
        }
        do {
                if (running)
                        seq = read_seqcount_begin(running);
-               bstats->bytes = b->bytes;
-               bstats->packets = b->packets;
+               bytes = b->bytes;
+               packets = b->packets;
        } while (running && read_seqcount_retry(running, seq));
+
+       bstats->bytes += bytes;
+       bstats->packets += packets;
 }
-EXPORT_SYMBOL(__gnet_stats_copy_basic);
+EXPORT_SYMBOL(gnet_stats_add_basic);
 
 static int
 ___gnet_stats_copy_basic(const seqcount_t *running,
@@ -166,7 +169,7 @@ ___gnet_stats_copy_basic(const seqcount_t *running,
 {
        struct gnet_stats_basic_packed bstats = {0};
 
-       __gnet_stats_copy_basic(running, &bstats, cpu, b);
+       gnet_stats_add_basic(running, &bstats, cpu, b);
 
        if (d->compat_tc_stats && type == TCA_STATS_BASIC) {
                d->tc_stats.bytes = bstats.bytes;
index e04f1a87642b9f9f68ed2261cff564c68e9c2c4b..1edd98a50e33d4c8b17efde7a911ddc41e7c328e 100644 (file)
@@ -147,9 +147,8 @@ static int mq_dump(struct Qdisc *sch, struct sk_buff *skb)
 
                if (qdisc_is_percpu_stats(qdisc)) {
                        qlen = qdisc_qlen_sum(qdisc);
-                       __gnet_stats_copy_basic(NULL, &sch->bstats,
-                                               qdisc->cpu_bstats,
-                                               &qdisc->bstats);
+                       gnet_stats_add_basic(NULL, &sch->bstats,
+                                            qdisc->cpu_bstats, &qdisc->bstats);
                        __gnet_stats_copy_queue(&sch->qstats,
                                                qdisc->cpu_qstats,
                                                &qdisc->qstats, qlen);
index e1904e62425e52a57ac1d42c19d7520336d871f1..4bae601e15e1eb33be41b66c430e3d06d15ec6d5 100644 (file)
@@ -405,9 +405,8 @@ static int mqprio_dump(struct Qdisc *sch, struct sk_buff *skb)
                if (qdisc_is_percpu_stats(qdisc)) {
                        __u32 qlen = qdisc_qlen_sum(qdisc);
 
-                       __gnet_stats_copy_basic(NULL, &sch->bstats,
-                                               qdisc->cpu_bstats,
-                                               &qdisc->bstats);
+                       gnet_stats_add_basic(NULL, &sch->bstats,
+                                            qdisc->cpu_bstats, &qdisc->bstats);
                        __gnet_stats_copy_queue(&sch->qstats,
                                                qdisc->cpu_qstats,
                                                &qdisc->qstats, qlen);
@@ -535,9 +534,9 @@ static int mqprio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
                        if (qdisc_is_percpu_stats(qdisc)) {
                                qlen = qdisc_qlen_sum(qdisc);
 
-                               __gnet_stats_copy_basic(NULL, &bstats,
-                                                       qdisc->cpu_bstats,
-                                                       &qdisc->bstats);
+                               gnet_stats_add_basic(NULL, &bstats,
+                                                    qdisc->cpu_bstats,
+                                                    &qdisc->bstats);
                                __gnet_stats_copy_queue(&qstats,
                                                        qdisc->cpu_qstats,
                                                        &qdisc->qstats,