mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-27 17:18:59 +00:00
b74386acc6
Use in tree version of cake for kernels 4.19+ and backport features from later kernel versions to 4.19. Unfortunately PROVIDES dependency handling produces bogus circular dependency warnings so whilst this package and kmod-sched-cake-oot should be able to PROVIDE kmod-sched-cake this doesn't work. Instead, remove the PROVIDES option and modify package sqm-scripts to depend on the correct module independently. Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
218 lines
6.8 KiB
Diff
218 lines
6.8 KiB
Diff
From 712639929912c5eefb09facccb48d55b3f72c9f8 Mon Sep 17 00:00:00 2001
|
|
From: George Amanakis <gamanakis@gmail.com>
|
|
Date: Fri, 1 Mar 2019 16:04:05 +0100
|
|
Subject: [PATCH] sch_cake: Make the dual modes fairer
|
|
MIME-Version: 1.0
|
|
Content-Type: text/plain; charset=UTF-8
|
|
Content-Transfer-Encoding: 8bit
|
|
|
|
CAKE host fairness does not work well with TCP flows in dual-srchost and
|
|
dual-dsthost setup. The reason is that ACKs generated by TCP flows are
|
|
classified as sparse flows, and affect flow isolation from other hosts. Fix
|
|
this by calculating host_load based only on the bulk flows a host
|
|
generates. In a hash collision the host_bulk_flow_count values must be
|
|
decremented on the old hosts and incremented on the new ones *if* the queue
|
|
is in the bulk set.
|
|
|
|
Reported-by: Pete Heist <peteheist@gmail.com>
|
|
Signed-off-by: George Amanakis <gamanakis@gmail.com>
|
|
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
|
|
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
|
|
---
|
|
net/sched/sch_cake.c | 92 ++++++++++++++++++++++++++++++--------------
|
|
1 file changed, 63 insertions(+), 29 deletions(-)
|
|
|
|
--- a/net/sched/sch_cake.c
|
|
+++ b/net/sched/sch_cake.c
|
|
@@ -138,8 +138,8 @@ struct cake_flow {
|
|
struct cake_host {
|
|
u32 srchost_tag;
|
|
u32 dsthost_tag;
|
|
- u16 srchost_refcnt;
|
|
- u16 dsthost_refcnt;
|
|
+ u16 srchost_bulk_flow_count;
|
|
+ u16 dsthost_bulk_flow_count;
|
|
};
|
|
|
|
struct cake_heap_entry {
|
|
@@ -746,8 +746,10 @@ skip_hash:
|
|
* queue, accept the collision, update the host tags.
|
|
*/
|
|
q->way_collisions++;
|
|
- q->hosts[q->flows[reduced_hash].srchost].srchost_refcnt--;
|
|
- q->hosts[q->flows[reduced_hash].dsthost].dsthost_refcnt--;
|
|
+ if (q->flows[outer_hash + k].set == CAKE_SET_BULK) {
|
|
+ q->hosts[q->flows[reduced_hash].srchost].srchost_bulk_flow_count--;
|
|
+ q->hosts[q->flows[reduced_hash].dsthost].dsthost_bulk_flow_count--;
|
|
+ }
|
|
allocate_src = cake_dsrc(flow_mode);
|
|
allocate_dst = cake_ddst(flow_mode);
|
|
found:
|
|
@@ -767,13 +769,14 @@ found:
|
|
}
|
|
for (i = 0; i < CAKE_SET_WAYS;
|
|
i++, k = (k + 1) % CAKE_SET_WAYS) {
|
|
- if (!q->hosts[outer_hash + k].srchost_refcnt)
|
|
+ if (!q->hosts[outer_hash + k].srchost_bulk_flow_count)
|
|
break;
|
|
}
|
|
q->hosts[outer_hash + k].srchost_tag = srchost_hash;
|
|
found_src:
|
|
srchost_idx = outer_hash + k;
|
|
- q->hosts[srchost_idx].srchost_refcnt++;
|
|
+ if (q->flows[reduced_hash].set == CAKE_SET_BULK)
|
|
+ q->hosts[srchost_idx].srchost_bulk_flow_count++;
|
|
q->flows[reduced_hash].srchost = srchost_idx;
|
|
}
|
|
|
|
@@ -789,13 +792,14 @@ found_src:
|
|
}
|
|
for (i = 0; i < CAKE_SET_WAYS;
|
|
i++, k = (k + 1) % CAKE_SET_WAYS) {
|
|
- if (!q->hosts[outer_hash + k].dsthost_refcnt)
|
|
+ if (!q->hosts[outer_hash + k].dsthost_bulk_flow_count)
|
|
break;
|
|
}
|
|
q->hosts[outer_hash + k].dsthost_tag = dsthost_hash;
|
|
found_dst:
|
|
dsthost_idx = outer_hash + k;
|
|
- q->hosts[dsthost_idx].dsthost_refcnt++;
|
|
+ if (q->flows[reduced_hash].set == CAKE_SET_BULK)
|
|
+ q->hosts[dsthost_idx].dsthost_bulk_flow_count++;
|
|
q->flows[reduced_hash].dsthost = dsthost_idx;
|
|
}
|
|
}
|
|
@@ -1793,20 +1797,30 @@ static s32 cake_enqueue(struct sk_buff *
|
|
b->sparse_flow_count++;
|
|
|
|
if (cake_dsrc(q->flow_mode))
|
|
- host_load = max(host_load, srchost->srchost_refcnt);
|
|
+ host_load = max(host_load, srchost->srchost_bulk_flow_count);
|
|
|
|
if (cake_ddst(q->flow_mode))
|
|
- host_load = max(host_load, dsthost->dsthost_refcnt);
|
|
+ host_load = max(host_load, dsthost->dsthost_bulk_flow_count);
|
|
|
|
flow->deficit = (b->flow_quantum *
|
|
quantum_div[host_load]) >> 16;
|
|
} else if (flow->set == CAKE_SET_SPARSE_WAIT) {
|
|
+ struct cake_host *srchost = &b->hosts[flow->srchost];
|
|
+ struct cake_host *dsthost = &b->hosts[flow->dsthost];
|
|
+
|
|
/* this flow was empty, accounted as a sparse flow, but actually
|
|
* in the bulk rotation.
|
|
*/
|
|
flow->set = CAKE_SET_BULK;
|
|
b->sparse_flow_count--;
|
|
b->bulk_flow_count++;
|
|
+
|
|
+ if (cake_dsrc(q->flow_mode))
|
|
+ srchost->srchost_bulk_flow_count++;
|
|
+
|
|
+ if (cake_ddst(q->flow_mode))
|
|
+ dsthost->dsthost_bulk_flow_count++;
|
|
+
|
|
}
|
|
|
|
if (q->buffer_used > q->buffer_max_used)
|
|
@@ -1974,23 +1988,8 @@ retry:
|
|
dsthost = &b->hosts[flow->dsthost];
|
|
host_load = 1;
|
|
|
|
- if (cake_dsrc(q->flow_mode))
|
|
- host_load = max(host_load, srchost->srchost_refcnt);
|
|
-
|
|
- if (cake_ddst(q->flow_mode))
|
|
- host_load = max(host_load, dsthost->dsthost_refcnt);
|
|
-
|
|
- WARN_ON(host_load > CAKE_QUEUES);
|
|
-
|
|
/* flow isolation (DRR++) */
|
|
if (flow->deficit <= 0) {
|
|
- /* The shifted prandom_u32() is a way to apply dithering to
|
|
- * avoid accumulating roundoff errors
|
|
- */
|
|
- flow->deficit += (b->flow_quantum * quantum_div[host_load] +
|
|
- (prandom_u32() >> 16)) >> 16;
|
|
- list_move_tail(&flow->flowchain, &b->old_flows);
|
|
-
|
|
/* Keep all flows with deficits out of the sparse and decaying
|
|
* rotations. No non-empty flow can go into the decaying
|
|
* rotation, so they can't get deficits
|
|
@@ -1999,6 +1998,13 @@ retry:
|
|
if (flow->head) {
|
|
b->sparse_flow_count--;
|
|
b->bulk_flow_count++;
|
|
+
|
|
+ if (cake_dsrc(q->flow_mode))
|
|
+ srchost->srchost_bulk_flow_count++;
|
|
+
|
|
+ if (cake_ddst(q->flow_mode))
|
|
+ dsthost->dsthost_bulk_flow_count++;
|
|
+
|
|
flow->set = CAKE_SET_BULK;
|
|
} else {
|
|
/* we've moved it to the bulk rotation for
|
|
@@ -2008,6 +2014,22 @@ retry:
|
|
flow->set = CAKE_SET_SPARSE_WAIT;
|
|
}
|
|
}
|
|
+
|
|
+ if (cake_dsrc(q->flow_mode))
|
|
+ host_load = max(host_load, srchost->srchost_bulk_flow_count);
|
|
+
|
|
+ if (cake_ddst(q->flow_mode))
|
|
+ host_load = max(host_load, dsthost->dsthost_bulk_flow_count);
|
|
+
|
|
+ WARN_ON(host_load > CAKE_QUEUES);
|
|
+
|
|
+ /* The shifted prandom_u32() is a way to apply dithering to
|
|
+ * avoid accumulating roundoff errors
|
|
+ */
|
|
+ flow->deficit += (b->flow_quantum * quantum_div[host_load] +
|
|
+ (prandom_u32() >> 16)) >> 16;
|
|
+ list_move_tail(&flow->flowchain, &b->old_flows);
|
|
+
|
|
goto retry;
|
|
}
|
|
|
|
@@ -2028,6 +2050,13 @@ retry:
|
|
&b->decaying_flows);
|
|
if (flow->set == CAKE_SET_BULK) {
|
|
b->bulk_flow_count--;
|
|
+
|
|
+ if (cake_dsrc(q->flow_mode))
|
|
+ srchost->srchost_bulk_flow_count--;
|
|
+
|
|
+ if (cake_ddst(q->flow_mode))
|
|
+ dsthost->dsthost_bulk_flow_count--;
|
|
+
|
|
b->decaying_flow_count++;
|
|
} else if (flow->set == CAKE_SET_SPARSE ||
|
|
flow->set == CAKE_SET_SPARSE_WAIT) {
|
|
@@ -2041,14 +2070,19 @@ retry:
|
|
if (flow->set == CAKE_SET_SPARSE ||
|
|
flow->set == CAKE_SET_SPARSE_WAIT)
|
|
b->sparse_flow_count--;
|
|
- else if (flow->set == CAKE_SET_BULK)
|
|
+ else if (flow->set == CAKE_SET_BULK) {
|
|
b->bulk_flow_count--;
|
|
- else
|
|
+
|
|
+ if (cake_dsrc(q->flow_mode))
|
|
+ srchost->srchost_bulk_flow_count--;
|
|
+
|
|
+ if (cake_ddst(q->flow_mode))
|
|
+ dsthost->dsthost_bulk_flow_count--;
|
|
+
|
|
+ } else
|
|
b->decaying_flow_count--;
|
|
|
|
flow->set = CAKE_SET_NONE;
|
|
- srchost->srchost_refcnt--;
|
|
- dsthost->dsthost_refcnt--;
|
|
}
|
|
goto begin;
|
|
}
|