@@ -102,7 +102,9 @@ static inline u32 codel_time_to_us(codel_time_t val)
* @interval: width of moving time window
* @mtu: device mtu, or minimal queue backlog in bytes.
* @ecn: is Explicit Congestion Notification enabled
- * @ce_threshold_ect1: if ce_threshold only marks ECT(1) packets
+ * @ce_threshold_selector: apply ce_threshold to packets matching this value
+ * in the diffserv/ECN byte of the IP header
+ * @ce_threshold_mask: mask to apply to ce_threshold_selector comparison
*/
struct codel_params {
codel_time_t target;
@@ -110,7 +112,8 @@ struct codel_params {
codel_time_t interval;
u32 mtu;
bool ecn;
- bool ce_threshold_ect1;
+ u8 ce_threshold_selector;
+ u8 ce_threshold_mask;
};
/**
@@ -54,7 +54,8 @@ static void codel_params_init(struct codel_params *params)
params->interval = MS2TIME(100);
params->target = MS2TIME(5);
params->ce_threshold = CODEL_DISABLED_THRESHOLD;
- params->ce_threshold_ect1 = false;
+ params->ce_threshold_mask = 0;
+ params->ce_threshold_selector = 0;
params->ecn = false;
}
@@ -250,13 +251,12 @@ static struct sk_buff *codel_dequeue(void *ctx,
if (skb && codel_time_after(vars->ldelay, params->ce_threshold)) {
bool set_ce = true;
- if (params->ce_threshold_ect1) {
- /* Note: if skb_get_dsfield() returns -1, following
- * gives INET_ECN_MASK, which is != INET_ECN_ECT_1.
- */
- u8 ecn = skb_get_dsfield(skb) & INET_ECN_MASK;
+ if (params->ce_threshold_mask) {
+ int dsfield = skb_get_dsfield(skb);
- set_ce = (ecn == INET_ECN_ECT_1);
+ set_ce = (dsfield >= 0 &&
+ (((u8)dsfield & params->ce_threshold_mask) ==
+ params->ce_threshold_selector));
}
if (set_ce && INET_ECN_set_ce(skb))
stats->ce_mark++;
@@ -840,7 +840,8 @@ enum {
TCA_FQ_CODEL_CE_THRESHOLD,
TCA_FQ_CODEL_DROP_BATCH_SIZE,
TCA_FQ_CODEL_MEMORY_LIMIT,
- TCA_FQ_CODEL_CE_THRESHOLD_ECT1,
+ TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR,
+ TCA_FQ_CODEL_CE_THRESHOLD_MASK,
__TCA_FQ_CODEL_MAX
};
@@ -513,7 +513,8 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
sta->cparams.target = MS2TIME(20);
sta->cparams.interval = MS2TIME(100);
sta->cparams.ecn = true;
- sta->cparams.ce_threshold_ect1 = false;
+ sta->cparams.ce_threshold_selector = 0;
+ sta->cparams.ce_threshold_mask = 0;
sta_dbg(sdata, "Allocated STA %pM\n", sta->sta.addr);
@@ -362,7 +362,8 @@ static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = {
[TCA_FQ_CODEL_CE_THRESHOLD] = { .type = NLA_U32 },
[TCA_FQ_CODEL_DROP_BATCH_SIZE] = { .type = NLA_U32 },
[TCA_FQ_CODEL_MEMORY_LIMIT] = { .type = NLA_U32 },
- [TCA_FQ_CODEL_CE_THRESHOLD_ECT1] = { .type = NLA_U8 },
+ [TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR] = { .type = NLA_U8 },
+ [TCA_FQ_CODEL_CE_THRESHOLD_MASK] = { .type = NLA_U8 },
};
static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt,
@@ -409,8 +410,10 @@ static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt,
q->cparams.ce_threshold = (val * NSEC_PER_USEC) >> CODEL_SHIFT;
}
- if (tb[TCA_FQ_CODEL_CE_THRESHOLD_ECT1])
- q->cparams.ce_threshold_ect1 = !!nla_get_u8(tb[TCA_FQ_CODEL_CE_THRESHOLD_ECT1]);
+ if (tb[TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR])
+ q->cparams.ce_threshold_selector = nla_get_u8(tb[TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR]);
+ if (tb[TCA_FQ_CODEL_CE_THRESHOLD_MASK])
+ q->cparams.ce_threshold_mask = nla_get_u8(tb[TCA_FQ_CODEL_CE_THRESHOLD_MASK]);
if (tb[TCA_FQ_CODEL_INTERVAL]) {
u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]);
@@ -552,7 +555,9 @@ static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
if (nla_put_u32(skb, TCA_FQ_CODEL_CE_THRESHOLD,
codel_time_to_us(q->cparams.ce_threshold)))
goto nla_put_failure;
- if (nla_put_u8(skb, TCA_FQ_CODEL_CE_THRESHOLD_ECT1, q->cparams.ce_threshold_ect1))
+ if (nla_put_u8(skb, TCA_FQ_CODEL_CE_THRESHOLD_SELECTOR, q->cparams.ce_threshold_selector))
+ goto nla_put_failure;
+ if (nla_put_u8(skb, TCA_FQ_CODEL_CE_THRESHOLD_MASK, q->cparams.ce_threshold_mask))
goto nla_put_failure;
}
The commit in the Fixes tag expanded the ce_threshold feature of FQ-CoDel so it can be applied to a subset of the traffic, using the ECT(1) bit of the ECN field as the classifier. However, hard-coding ECT(1) as the only classifier for this feature seems limiting, so let's expand it to be more general. To this end, change the parameter from a ce_threshold_ect1 boolean, to a one-byte selector/mask pair (ce_threshold_{selector,mask}) which is applied to the whole diffserv/ECN field in the IP header. This makes it possible to classify packets by any value in either the ECN field or the diffserv field. In particular, setting a selector of INET_ECN_ECT_1 and a mask of INET_ECN_MASK corresponds to the functionality before this patch, and a mask of ~INET_ECN_MASK allows using the selector as a straight-forward match against a diffserv code point. Regardless of the selector chosen, the normal rules for ECN-marking of packets still apply, i.e., the flow must still declare itself ECN-capable by setting one of the bits in the ECN field to get marked at all. Fixes: e72aeb9ee0e3 ("fq_codel: implement L4S style ce_threshold_ect1 marking") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> --- include/net/codel.h | 7 +++++-- include/net/codel_impl.h | 14 +++++++------- include/uapi/linux/pkt_sched.h | 3 ++- net/mac80211/sta_info.c | 3 ++- net/sched/sch_fq_codel.c | 13 +++++++++---- 5 files changed, 25 insertions(+), 15 deletions(-)