Re: [PATCH] net: sched: tbf: handle GSO_BY_FRAGS case in enqueue
Hi Marcelo,
>
> If this block was meant to be an out-of-band/changelog comment, your
> SOB line should be above the first --- marker.
> Anyhow,
> Reviewed-by: Marcelo Ricardo Leitner
Thanks - I did a v2 with this around the right way [1], but DaveM asked
me to be a bit more thorough and look for other GSO_BY_FRAGS issues. [2]
I did find a couple, including the one I asked you about with
qdisk_pkt_len_init [3] (thanks for your answer, btw). Currently I'm
trying to wrap my head around GSO_DODGY as Eric mentioned on that
thread, and then I'll do a series with this fix and the other
GSO_BY_FRAGS fixes I find.
Regards,
Daniel
[1] https://patchwork.ozlabs.org/patch/869145/
[2] https://patchwork.ozlabs.org/comment/1852414/
[3] https://www.spinics.net/lists/netdev/msg482397.html
>
>> ---
>> net/sched/sch_tbf.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
>> index 229172d509cc..03225a8df973 100644
>> --- a/net/sched/sch_tbf.c
>> +++ b/net/sched/sch_tbf.c
>> @@ -188,7 +188,8 @@ static int tbf_enqueue(struct sk_buff *skb, struct Qdisc
>> *sch,
>> int ret;
>>
>> if (qdisc_pkt_len(skb) > q->max_size) {
>> -if (skb_is_gso(skb) && skb_gso_mac_seglen(skb) <= q->max_size)
>> +if (skb_is_gso(skb) &&
>> +skb_gso_validate_mac_len(skb, q->max_size))
>> return tbf_segment(skb, sch, to_free);
>> return qdisc_drop(skb, sch, to_free);
>> }
>> --
>> 2.14.1
>>
Re: [PATCH] net: sched: tbf: handle GSO_BY_FRAGS case in enqueue
On Mon, Feb 05, 2018 at 02:34:33PM +1100, Daniel Axtens wrote:
> tbf_enqueue() checks the size of a packet before enqueuing it.
> However, the GSO size check does not consider the GSO_BY_FRAGS
> case, and so will drop GSO SCTP packets, causing a massive drop
> in throughput.
>
> Use skb_gso_validate_mac_len() instead, as it does consider that
> case.
>
> ---
>
> skb_gso_validate_mac_len() is an out-of-line call, but so is
> skb_gso_mac_seglen(), so this is slower but not much slower. I
> will send a patch to make the skb_gso_validate_* functions
> inline-able shortly.
>
> Also, GSO_BY_FRAGS considered harmful - I'm pretty sure this is
> not the only place it causes issues.
Thanks for spotting these issues and fixing them.
>
> Signed-off-by: Daniel Axtens
If this block was meant to be an out-of-band/changelog comment, your
SOB line should be above the first --- marker.
Anyhow,
Reviewed-by: Marcelo Ricardo Leitner
> ---
> net/sched/sch_tbf.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
> index 229172d509cc..03225a8df973 100644
> --- a/net/sched/sch_tbf.c
> +++ b/net/sched/sch_tbf.c
> @@ -188,7 +188,8 @@ static int tbf_enqueue(struct sk_buff *skb, struct Qdisc
> *sch,
> int ret;
>
> if (qdisc_pkt_len(skb) > q->max_size) {
> - if (skb_is_gso(skb) && skb_gso_mac_seglen(skb) <= q->max_size)
> + if (skb_is_gso(skb) &&
> + skb_gso_validate_mac_len(skb, q->max_size))
> return tbf_segment(skb, sch, to_free);
> return qdisc_drop(skb, sch, to_free);
> }
> --
> 2.14.1
>
[PATCH] net: sched: tbf: handle GSO_BY_FRAGS case in enqueue
tbf_enqueue() checks the size of a packet before enqueuing it.
However, the GSO size check does not consider the GSO_BY_FRAGS
case, and so will drop GSO SCTP packets, causing a massive drop
in throughput.
Use skb_gso_validate_mac_len() instead, as it does consider that
case.
---
skb_gso_validate_mac_len() is an out-of-line call, but so is
skb_gso_mac_seglen(), so this is slower but not much slower. I
will send a patch to make the skb_gso_validate_* functions
inline-able shortly.
Also, GSO_BY_FRAGS considered harmful - I'm pretty sure this is
not the only place it causes issues.
Signed-off-by: Daniel Axtens
---
net/sched/sch_tbf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
index 229172d509cc..03225a8df973 100644
--- a/net/sched/sch_tbf.c
+++ b/net/sched/sch_tbf.c
@@ -188,7 +188,8 @@ static int tbf_enqueue(struct sk_buff *skb, struct Qdisc
*sch,
int ret;
if (qdisc_pkt_len(skb) > q->max_size) {
- if (skb_is_gso(skb) && skb_gso_mac_seglen(skb) <= q->max_size)
+ if (skb_is_gso(skb) &&
+ skb_gso_validate_mac_len(skb, q->max_size))
return tbf_segment(skb, sch, to_free);
return qdisc_drop(skb, sch, to_free);
}
--
2.14.1
