Commit Graph

1232 Commits

Author SHA1 Message Date
Eric Dumazet
4a8e320c92 net: sched: use pinned timers
While using a MQ + NETEM setup, I had confirmation that the default
timer migration ( /proc/sys/kernel/timer_migration ) is killing us.

Installing this on a receiver side of a TCP_STREAM test, (NIC has 8 TX
queues) :

EST="est 1sec 4sec"
for ETH in eth1
do
 tc qd del dev $ETH root 2>/dev/null
 tc qd add dev $ETH root handle 1: mq
 tc qd add dev $ETH parent 1:1 $EST netem limit 70000 delay 6ms
 tc qd add dev $ETH parent 1:2 $EST netem limit 70000 delay 8ms
 tc qd add dev $ETH parent 1:3 $EST netem limit 70000 delay 10ms
 tc qd add dev $ETH parent 1:4 $EST netem limit 70000 delay 12ms
 tc qd add dev $ETH parent 1:5 $EST netem limit 70000 delay 14ms
 tc qd add dev $ETH parent 1:6 $EST netem limit 70000 delay 16ms
 tc qd add dev $ETH parent 1:7 $EST netem limit 80000 delay 18ms
 tc qd add dev $ETH parent 1:8 $EST netem limit 90000 delay 20ms
done

We can see that timers get migrated into a single cpu, presumably idle
at the time timers are set up.
Then all qdisc dequeues run from this cpu and huge lock contention
happens. This single cpu is stuck in softirq mode and cannot dequeue
fast enough.

    39.24%  [kernel]          [k] _raw_spin_lock
     2.65%  [kernel]          [k] netem_enqueue
     1.80%  [kernel]          [k] netem_dequeue
     1.63%  [kernel]          [k] copy_user_enhanced_fast_string
     1.45%  [kernel]          [k] _raw_spin_lock_bh

By pinning qdisc timers on the cpu running the qdisc, we respect proper
XPS setting and remove this lock contention.

     5.84%  [kernel]          [k] netem_enqueue
     4.83%  [kernel]          [k] _raw_spin_lock
     2.92%  [kernel]          [k] copy_user_enhanced_fast_string

Current Qdiscs that benefit from this change are :

	netem, cbq, fq, hfsc, tbf, htb.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-26 00:26:48 -04:00
David S. Miller
1f6d80358d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	arch/mips/net/bpf_jit.c
	drivers/net/can/flexcan.c

Both the flexcan and MIPS bpf_jit conflicts were cases of simple
overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-23 12:09:27 -04:00
Eric Dumazet
a2aeb02a8e net: sched: fix compile warning in cls_u32
$ grep CONFIG_CLS_U32_MARK .config
# CONFIG_CLS_U32_MARK is not set

net/sched/cls_u32.c: In function 'u32_change':
net/sched/cls_u32.c:852:1: warning: label 'errout' defined but not used
[-Wunused-label]

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-22 16:47:19 -04:00
John Fastabend
de5df63228 net: sched: cls_u32 changes to knode must appear atomic to readers
Changes to the cls_u32 classifier must appear atomic to the
readers. Before this patch if a change is requested for both
the exts and ifindex, first the ifindex is updated then the
exts with tcf_exts_change(). This opens a small window where
a reader can have a exts chain with an incorrect ifindex. This
violates the the RCU semantics.

Here we resolve this by always passing u32_set_parms() a copy
of the tc_u_knode to work on and then inserting it into the hash
table after the updates have been successfully applied.

Tested with the following short script:

#tc filter add dev p3p2 parent 8001:0 protocol ip prio 99 handle 1: \
	       u32 divisor 256

#tc filter add dev p3p2 parent 8001:0 protocol ip prio 99 \
	       u32 link 1: hashkey mask ffffff00 at 12    \
	       match ip src 192.168.8.0/2

#tc filter add dev p3p2 parent 8001:0 protocol ip prio 102    \
	       handle 1::10 u32 classid 1:2 ht 1: 	      \
	       match ip src 192.168.8.0/8 match ip tos 0x0a 1e

#tc filter change dev p3p2 parent 8001:0 protocol ip prio 102 \
		 handle 1::10 u32 classid 1:2 ht 1:        \
		 match ip src 1.1.0.0/8 match ip tos 0x0b 1e

CC: Eric Dumazet <edumazet@google.com>
CC: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-22 15:59:21 -04:00
John Fastabend
a1ddcfee2d net: cls_u32: fix missed pcpu_success free_percpu
This fixes a missed free_percpu in the unwind code path and when
keys are destroyed.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-22 15:59:21 -04:00
Eric Dumazet
2571178626 net: sched: shrink struct qdisc_skb_cb to 28 bytes
We cannot make struct qdisc_skb_cb bigger without impacting IPoIB,
or increasing skb->cb[] size.

Commit e0f31d8498 ("flow_keys: Record IP layer protocol in
skb_flow_dissect()") broke IPoIB.

Only current offender is sch_choke, and this one do not need an
absolutely precise flow key.

If we store 17 bytes of flow key, its more than enough. (Its the actual
size of flow_keys if it was a packed structure, but we might add new
fields at the end of it later)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: e0f31d8498 ("flow_keys: Record IP layer protocol in skb_flow_dissect()")
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-22 14:21:47 -04:00
John Fastabend
4e2840eee6 net: sched: cls_u32: rcu can not be last node
tc_u32_sel 'sel' in tc_u_knode expects to be the last element in the
structure and pads the structure with tc_u32_key fields for each key.

 kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL)

CC: Eric Dumazet <edumazet@google.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-19 17:05:45 -04:00
Eric Dumazet
ab34f64808 net: sched: use __skb_queue_head_init() where applicable
pfifo_fast and htb use skb lists, without needing their spinlocks.
(They instead use the standard qdisc lock)

We can use __skb_queue_head_init() instead of skb_queue_head_init()
to be consistent.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-19 16:32:10 -04:00
John Fastabend
9f6c38e70b net: sched: cls_cgroup need tcf_exts_init in all cases
This ensures the tcf_exts_init() is called for all cases.

Fixes: 952313bd62 ("net: sched: cls_cgroup use RCU")
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16 16:26:39 -04:00
John Fastabend
e1f93eb06c net: sched: cls_fw: add missing tcf_exts_init call in fw_change()
When allocating a new structure we also need to call tcf_exts_init
to initialize exts.

A follow up patch might be in order to remove some of this code
and do tcf_exts_assign(). With this we could remove the
tcf_exts_init/tcf_exts_change pattern for some of the classifiers.
As part of the future tcf_actions RCU series this will need to be
done. For now fix the call here.

Fixes e35a8ee599 ("net: sched: fw use RCU")
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16 15:59:36 -04:00
John Fastabend
d14cbfc88f net: sched: cls_cgroup fix possible memory leak of 'new'
tree:   git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git master
head:   54996b529a
commit: c7953ef230 [625/646] net: sched: cls_cgroup use RCU

net/sched/cls_cgroup.c:130 cls_cgroup_change() warn: possible memory leak of 'new'
net/sched/cls_cgroup.c:135 cls_cgroup_change() warn: possible memory leak of 'new'
net/sched/cls_cgroup.c:139 cls_cgroup_change() warn: possible memory leak of 'new'

Fixes: c7953ef230 ("net: sched: cls_cgroup use RCU")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16 15:59:36 -04:00
John Fastabend
a96366bf26 net: sched: cls_u32 add missing rcu_assign_pointer and annotation
Add missing rcu_assign_pointer and missing  annotation for ht_up
in cls_u32.c

Caught by kbuild bot,

>> net/sched/cls_u32.c:378:36: sparse: incorrect type in initializer (different address spaces)
   net/sched/cls_u32.c:378:36:    expected struct tc_u_hnode *ht
   net/sched/cls_u32.c:378:36:    got struct tc_u_hnode [noderef] <asn:4>*ht_up
>> net/sched/cls_u32.c:610:54: sparse: incorrect type in argument 4 (different address spaces)
   net/sched/cls_u32.c:610:54:    expected struct tc_u_hnode *ht
   net/sched/cls_u32.c:610:54:    got struct tc_u_hnode [noderef] <asn:4>*ht_up
>> net/sched/cls_u32.c:684:18: sparse: incorrect type in assignment (different address spaces)
   net/sched/cls_u32.c:684:18:    expected struct tc_u_hnode [noderef] <asn:4>*ht_up
   net/sched/cls_u32.c:684:18:    got struct tc_u_hnode *[assigned] ht
>> net/sched/cls_u32.c:359:18: sparse: dereference of noderef expression

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16 15:59:36 -04:00
John Fastabend
80aab73de4 net: sched: fix unsued cpu variable
kbuild test robot reported an unused variable cpu in cls_u32.c
after the patch below. This happens when PERF and MARK config
variables are disabled

Fix this is to use separate variables for perf and mark
and define the cpu variable inside the ifdef logic.

Fixes: 459d5f626d ("net: sched: make cls_u32 per cpu")'
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16 15:59:36 -04:00
WANG Cong
69301eaa7f net_sched: fix a null pointer dereference in tcindex_set_parms()
This patch fixes the following crash:

[   42.199159] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
[   42.200027] IP: [<ffffffff817e3fc4>] tcindex_set_parms+0x45c/0x526
[   42.200027] PGD d2319067 PUD d4ffe067 PMD 0
[   42.200027] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[   42.200027] CPU: 0 PID: 541 Comm: tc Not tainted 3.17.0-rc4+ #603
[   42.200027] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   42.200027] task: ffff8800d22d2670 ti: ffff8800ce790000 task.ti: ffff8800ce790000
[   42.200027] RIP: 0010:[<ffffffff817e3fc4>]  [<ffffffff817e3fc4>] tcindex_set_parms+0x45c/0x526
[   42.200027] RSP: 0018:ffff8800ce793898  EFLAGS: 00010202
[   42.200027] RAX: 0000000000000001 RBX: ffff8800d1786498 RCX: 0000000000000000
[   42.200027] RDX: ffffffff82114ec8 RSI: ffffffff82114ec8 RDI: ffffffff82114ec8
[   42.200027] RBP: ffff8800ce793958 R08: 00000000000080d0 R09: 0000000000000001
[   42.200027] R10: ffff8800ce7939a0 R11: 0000000000000246 R12: ffff8800d017d238
[   42.200027] R13: 0000000000000018 R14: ffff8800d017c6a0 R15: ffff8800d1786620
[   42.200027] FS:  00007f4e24539740(0000) GS:ffff88011a600000(0000) knlGS:0000000000000000
[   42.200027] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   42.200027] CR2: 0000000000000018 CR3: 00000000cff38000 CR4: 00000000000006f0
[   42.200027] Stack:
[   42.200027]  ffff8800ce0949f0 0000000000000000 0000000200000003 ffff880000000000
[   42.200027]  ffff8800ce7938b8 ffff8800ce7938b8 0000000600000007 0000000000000000
[   42.200027]  ffff8800ce7938d8 ffff8800ce7938d8 0000000600000007 ffff8800ce0949f0
[   42.200027] Call Trace:
[   42.200027]  [<ffffffff817e4169>] tcindex_change+0xdb/0xee
[   42.200027]  [<ffffffff817c16ca>] tc_ctl_tfilter+0x44d/0x63f
[   42.200027]  [<ffffffff8179d161>] rtnetlink_rcv_msg+0x181/0x194
[   42.200027]  [<ffffffff8179cf9d>] ? rtnl_lock+0x17/0x19
[   42.200027]  [<ffffffff8179cfe0>] ? __rtnl_unlock+0x17/0x17
[   42.200027]  [<ffffffff817ee296>] netlink_rcv_skb+0x49/0x8b
[   43.462494]  [<ffffffff8179cfc2>] rtnetlink_rcv+0x23/0x2a
[   43.462494]  [<ffffffff817ec8df>] netlink_unicast+0xc7/0x148
[   43.462494]  [<ffffffff817ed413>] netlink_sendmsg+0x5cb/0x63d
[   43.462494]  [<ffffffff810ad781>] ? mark_lock+0x2e/0x224
[   43.462494]  [<ffffffff817757b8>] __sock_sendmsg_nosec+0x25/0x27
[   43.462494]  [<ffffffff81778165>] sock_sendmsg+0x57/0x71
[   43.462494]  [<ffffffff81152bbd>] ? might_fault+0x57/0xa4
[   43.462494]  [<ffffffff81152c06>] ? might_fault+0xa0/0xa4
[   43.462494]  [<ffffffff81152bbd>] ? might_fault+0x57/0xa4
[   43.462494]  [<ffffffff817838fd>] ? verify_iovec+0x69/0xb7
[   43.462494]  [<ffffffff817784f8>] ___sys_sendmsg+0x21d/0x2bb
[   43.462494]  [<ffffffff81009db3>] ? native_sched_clock+0x35/0x37
[   43.462494]  [<ffffffff8109ab53>] ? sched_clock_local+0x12/0x72
[   43.462494]  [<ffffffff810ad781>] ? mark_lock+0x2e/0x224
[   43.462494]  [<ffffffff8109ada4>] ? sched_clock_cpu+0xa0/0xb9
[   43.462494]  [<ffffffff810aee37>] ? __lock_acquire+0x5fe/0xde4
[   43.462494]  [<ffffffff8119f570>] ? rcu_read_lock_held+0x36/0x38
[   43.462494]  [<ffffffff8119f75a>] ? __fcheck_files.isra.7+0x4b/0x57
[   43.462494]  [<ffffffff8119fbf2>] ? __fget_light+0x30/0x54
[   43.462494]  [<ffffffff81779012>] __sys_sendmsg+0x42/0x60
[   43.462494]  [<ffffffff81779042>] SyS_sendmsg+0x12/0x1c
[   43.462494]  [<ffffffff819d24d2>] system_call_fastpath+0x16/0x1b

'p->h' could be NULL while 'cp->h' is always update to date.

Fixes: commit 331b72922c ("net: sched: RCU cls_tcindex")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-By: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16 15:20:09 -04:00
WANG Cong
44b75e4317 net_sched: fix memory leak in cls_tcindex
Fixes: commit 331b72922c ("net: sched: RCU cls_tcindex")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-By: John Fastabend <john.r.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-16 15:19:23 -04:00
WANG Cong
10ee1c34be net_sched: use tcindex_filter_result_init()
Fixes: commit 331b72922c ("net: sched: RCU cls_tcindex")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-15 17:51:18 -04:00
WANG Cong
2f9a220eff net_sched: fix suspicious RCU usage in tcindex_classify()
This patch fixes the following kernel warning:

[   44.805900] [ INFO: suspicious RCU usage. ]
[   44.808946] 3.17.0-rc4+ #610 Not tainted
[   44.811831] -------------------------------
[   44.814873] net/sched/cls_tcindex.c:84 suspicious rcu_dereference_check() usage!

Fixes: commit 331b72922c ("net: sched: RCU cls_tcindex")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-15 17:49:42 -04:00
WANG Cong
a57a65ba47 net_sched: fix an allocation bug in tcindex_set_parms()
Fixes: commit 331b72922c ("net: sched: RCU cls_tcindex")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-15 17:48:23 -04:00
WANG Cong
80dcbd12fb net_sched: fix suspicious RCU usage in cls_bpf_classify()
Fixes: commit 1f947bf151 ("net: sched: rcu'ify cls_bpf")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-15 17:42:08 -04:00
John Fastabend
1f947bf151 net: sched: rcu'ify cls_bpf
This patch makes the cls_bpf classifier RCU safe. The tcf_lock
was being used to protect a list of cls_bpf_prog now this list
is RCU safe and updates occur with rcu_replace.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
b929d86d25 net: sched: rcu'ify cls_rsvp
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
1ce87720d4 net: sched: make cls_u32 lockless
Make cls_u32 classifier safe to run without holding lock. This patch
converts statistics that are kept in read section u32_classify into
per cpu counters.

This patch was tested with a tight u32 filter add/delete loop while
generating traffic with pktgen. By running pktgen on vlan devices
created on top of a physical device we can hit the qdisc layer
correctly. For ingress qdisc's a loopback cable was used.

for i in {1..100}; do
        q=`echo $i%8|bc`;
        echo -n "u32 tos: iteration $i on queue $q";
        tc filter add dev p3p2 parent $p prio $i u32 match ip tos 0x10 0xff \
                  action skbedit queue_mapping $q;
        sleep 1;
        tc filter del dev p3p2 prio $i;

        echo -n "u32 tos hash table: iteration $i on queue $q";
        tc filter add dev p3p2 parent $p protocol ip prio $i handle 628: u32 divisor 1
        tc filter add dev p3p2 parent $p protocol ip prio $i u32 \
                match ip protocol 17 0xff link 628: offset at 0 mask 0xf00 shift 6 plus 0
        tc filter add dev p3p2 parent $p protocol ip prio $i u32 \
                ht 628:0 match ip tos 0x10 0xff action skbedit queue_mapping $q
        sleep 2;
        tc filter del dev p3p2 prio $i
        sleep 1;
done

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
459d5f626d net: sched: make cls_u32 per cpu
This uses per cpu counters in cls_u32 in preparation
to convert over to rcu.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
331b72922c net: sched: RCU cls_tcindex
Make cls_tcindex RCU safe.

This patch addds a new RCU routine rcu_dereference_bh_rtnl() to check
caller either holds the rcu read lock or RTNL. This is needed to
handle the case where tcindex_lookup() is being called in both cases.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
1109c00547 net: sched: RCU cls_route
RCUify the route classifier. For now however spinlock's are used to
protect fastmap cache.

The issue here is the fastmap may be read by one CPU while the
cache is being updated by another. An array of pointers could be
one possible solution.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
e35a8ee599 net: sched: fw use RCU
RCU'ify fw classifier.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
70da9f0bf9 net: sched: cls_flow use RCU
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
952313bd62 net: sched: cls_cgroup use RCU
Make cgroup classifier safe for RCU.

Also drops the calls in the classify routine that were doing a
rcu_read_lock()/rcu_read_unlock(). If the rcu_read_lock() isn't held
entering this routine we have issues with deleting the classifier
chain so remove the unnecessary rcu_read_lock()/rcu_read_unlock()
pair noting all paths AFAIK hold rcu_read_lock.

If there is a case where classify is called without the rcu read lock
then an rcu splat will occur and we can correct it.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:26 -04:00
John Fastabend
9888faefe1 net: sched: cls_basic use RCU
Enable basic classifier for RCU.

Dereferencing tp->root may look a bit strange here but it is needed
by my accounting because it is allocated at init time and needs to
be kfree'd at destroy time. However because it may be referenced in
the classify() path we must wait an RCU grace period before free'ing
it. We use kfree_rcu() and rcu_ APIs to enforce this. This pattern
is used in all the classifiers.

Also the hgenerator can be incremented without concern because it
is always incremented under RTNL.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:25 -04:00
John Fastabend
25d8c0d55f net: rcu-ify tcf_proto
rcu'ify tcf_proto this allows calling tc_classify() without holding
any locks. Updaters are protected by RTNL.

This patch prepares the core net_sched infrastracture for running
the classifier/action chains without holding the qdisc lock however
it does nothing to ensure cls_xxx and act_xxx types also work without
locking. Additional patches are required to address the fall out.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:25 -04:00
John Fastabend
46e5da40ae net: qdisc: use rcu prefix and silence sparse warnings
Add __rcu notation to qdisc handling by doing this we can make
smatch output more legible. And anyways some of the cases should
be using rcu_dereference() see qdisc_all_tx_empty(),
qdisc_tx_chainging(), and so on.

Also *wake_queue() API is commonly called from driver timer routines
without rcu lock or rtnl lock. So I added rcu_read_lock() blocks
around netif_wake_subqueue and netif_tx_wake_queue.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13 12:30:25 -04:00
Florian Westphal
17448e5f63 net_sched: sfq: remove unused macro
not used anymore since ddecf0f
(net_sched: sfq: add optional RED on top of SFQ).

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-09 17:34:41 -07:00
Jesper Dangaard Brouer
3f3c7eec60 qdisc: exit case fixes for skb list handling in qdisc layer
More minor fixes to merge commit 53fda7f7f9 (Merge branch 'xmit_list')
that allows us to work with a list of SKBs.

Fixing exit cases in qdisc_reset() and qdisc_destroy(), where a
leftover requeued SKB (qdisc->gso_skb) can have the potential of
being a skb list, thus use kfree_skb_list().

This is a followup to commit 10770bc2d1 ("qdisc: adjustments for
API allowing skb list xmits").

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-03 20:41:42 -07:00
Jesper Dangaard Brouer
10770bc2d1 qdisc: adjustments for API allowing skb list xmits
Minor adjustments for merge commit 53fda7f7f9 (Merge branch 'xmit_list')
that allows us to work with a list of SKBs.

Update code doc to function sch_direct_xmit().

In handle_dev_cpu_collision() use kfree_skb_list() in error handling.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-02 14:06:17 -07:00
David S. Miller
ce93718fb7 net: Don't keep around original SKB when we software segment GSO frames.
Just maintain the list properly by returning the head of the remaining
SKB list from dev_hard_start_xmit().

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:56 -07:00
David S. Miller
50cbe9ab5f net: Validate xmit SKBs right when we pull them out of the qdisc.
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:56 -07:00
David S. Miller
fa2dbdc253 net: Pass a "more" indication down into netdev_start_xmit() code paths.
For now it will always be false.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:55 -07:00
David S. Miller
10b3ad8c21 net: Do txq_trans_update() in netdev_start_xmit()
That way we don't have to audit every call site to make sure it is
doing this properly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-01 17:39:55 -07:00
Daniel Borkmann
10c51b5623 net: add skb_get_tx_queue() helper
Replace occurences of skb_get_queue_mapping() and follow-up
netdev_get_tx_queue() with an actual helper function.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-29 20:02:07 -07:00
David S. Miller
4798248e4e net: Add ops->ndo_xmit_flush()
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-24 23:02:45 -07:00
Daniel Borkmann
8fc54f6891 net: use reciprocal_scale() helper
Replace open codings of (((u64) <x> * <y>) >> 32) with reciprocal_scale().

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23 12:21:21 -07:00
David S. Miller
f9474ddfaa Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pulling to get some TIPC fixes that a net-next series depends
upon.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23 11:12:08 -07:00
Eric Dumazet
d2de875c6d net: use ktime_get_ns() and ktime_get_real_ns() helpers
ktime_get_ns() replaces ktime_to_ns(ktime_get())

ktime_get_real_ns() replaces ktime_to_ns(ktime_get_real())

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-22 19:57:23 -07:00
Vasily Averin
7201c1ddf7 cbq: now_rt removal
Now q->now_rt is identical to q->now and is not required anymore.

Signed-off-by: Vasily Averin <vvs@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-19 10:58:44 -07:00
Vasily Averin
73d0f37ac4 cbq: incorrectly low bandwidth setting blocks limited traffic
Mainstream commit f0f6ee1f70 ("cbq: incorrect processing of high limits")
have side effect: if cbq bandwidth setting is less than real interface
throughput non-limited traffic can delay limited traffic for a very long time.

This happen because of q->now changes incorrectly in cbq_dequeue():
in described scenario L2T is much greater than real time delay,
and q->now gets an extra boost for each transmitted packet.

Accumulated boost prevents update q->now, and blocked class can wait
very long time until (q->now >= cl->undertime) will be true again.

To fix the problem the patch updates q->now on each cbq_update() call.
L2T-related pre-modification q->now was moved to cbq_update().

My testing confirmed that it fixes the problem and did not discover
any side-effects

Fixes: f0f6ee1f70 ("cbq: incorrect processing of high limits")

Signed-off-by: Vasily Averin <vvs@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-19 10:58:44 -07:00
Alexei Starovoitov
7ae457c1e5 net: filter: split 'struct sk_filter' into socket and bpf parts
clean up names related to socket filtering and bpf in the following way:
- everything that deals with sockets keeps 'sk_*' prefix
- everything that is pure BPF is changed to 'bpf_*' prefix

split 'struct sk_filter' into
struct sk_filter {
	atomic_t        refcnt;
	struct rcu_head rcu;
	struct bpf_prog *prog;
};
and
struct bpf_prog {
        u32                     jited:1,
                                len:31;
        struct sock_fprog_kern  *orig_prog;
        unsigned int            (*bpf_func)(const struct sk_buff *skb,
                                            const struct bpf_insn *filter);
        union {
                struct sock_filter      insns[0];
                struct bpf_insn         insnsi[0];
                struct work_struct      work;
        };
};
so that 'struct bpf_prog' can be used independent of sockets and cleans up
'unattached' bpf use cases

split SK_RUN_FILTER macro into:
    SK_RUN_FILTER to be used with 'struct sk_filter *' and
    BPF_PROG_RUN to be used with 'struct bpf_prog *'

__sk_filter_release(struct sk_filter *) gains
__bpf_prog_release(struct bpf_prog *) helper function

also perform related renames for the functions that work
with 'struct bpf_prog *', since they're on the same lines:

sk_filter_size -> bpf_prog_size
sk_filter_select_runtime -> bpf_prog_select_runtime
sk_filter_free -> bpf_prog_free
sk_unattached_filter_create -> bpf_prog_create
sk_unattached_filter_destroy -> bpf_prog_destroy
sk_store_orig_filter -> bpf_prog_store_orig_filter
sk_release_orig_filter -> bpf_release_orig_filter
__sk_migrate_filter -> bpf_migrate_filter
__sk_prepare_filter -> bpf_prepare_filter

API for attaching classic BPF to a socket stays the same:
sk_attach_filter(prog, struct sock *)/sk_detach_filter(struct sock *)
and SK_RUN_FILTER(struct sk_filter *, ctx) to execute a program
which is used by sockets, tun, af_packet

API for 'unattached' BPF programs becomes:
bpf_prog_create(struct bpf_prog **)/bpf_prog_destroy(struct bpf_prog *)
and BPF_PROG_RUN(struct bpf_prog *, ctx) to execute a program
which is used by isdn, ppp, team, seccomp, ptp, xt_bpf, cls_bpf, test_bpf

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-02 15:03:58 -07:00
Himangi Saraogi
e40f5c7234 net_sched: remove exceptional & on function name
In this file, function names are otherwise used as pointers without &.

A simplified version of the Coccinelle semantic patch that makes this
change is as follows:

// <smpl>
@r@
identifier f;
@@

f(...) { ... }

@@
identifier r.f;
@@

- &f
+ f
// </smpl>

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-24 23:23:32 -07:00
David S. Miller
8fd90bb889 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/infiniband/hw/cxgb4/device.c

The cxgb4 conflict was simply overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-22 00:44:59 -07:00
Cong Wang
7801db8aec net_sched: avoid generating same handle for u32 filters
When kernel generates a handle for a u32 filter, it tries to start
from the max in the bucket. So when we have a filter with the max (fff)
handle, it will cause kernel always generates the same handle for new
filters. This can be shown by the following command:

	tc qdisc add dev eth0 ingress
	tc filter add dev eth0 parent ffff: protocol ip pref 770 handle 800::fff u32 match ip protocol 1 0xff
	tc filter add dev eth0 parent ffff: protocol ip pref 770 u32 match ip protocol 1 0xff
	...

we will get some u32 filters with same handle:

 # tc filter show dev eth0 parent ffff:
filter protocol ip pref 770 u32
filter protocol ip pref 770 u32 fh 800: ht divisor 1
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8

handles should be unique. This patch fixes it by looking up a bitmap,
so that can guarantee the handle is as unique as possible. For compatibility,
we still start from 0x800.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-20 20:49:17 -07:00
Cong Wang
224e923cd9 net_sched: hold tcf_lock in netdevice notifier
We modify mirred action (m->tcfm_dev) in netdev event, we need to
prevent on-going mirred actions from reading freed m->tcfm_dev.
So we need to acquire this spin lock.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-20 20:31:42 -07:00