Commit Graph

57 Commits

Author SHA1 Message Date
David S. Miller
a8305bff68 net: Add and use skb_mark_not_on_list().
An SKB is not on a list if skb->next is NULL.

Codify this convention into a helper function and use it
where we are dequeueing an SKB and need to mark it as such.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-10 10:06:54 -07:00
Jacob Keller
83fe6b8709 sch_fq_codel: zero q->flows_cnt when fq_codel_init fails
When fq_codel_init fails, qdisc_create_dflt will cleanup by using
qdisc_destroy. This function calls the ->reset() op prior to calling the
->destroy() op.

Unfortunately, during the failure flow for sch_fq_codel, the ->flows
parameter is not initialized, so the fq_codel_reset function will null
pointer dereference.

   kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
   kernel: IP: fq_codel_reset+0x58/0xd0 [sch_fq_codel]
   kernel: PGD 0 P4D 0
   kernel: Oops: 0000 [#1] SMP PTI
   kernel: Modules linked in: i40iw i40e(OE) xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack tun bridge stp llc devlink ebtable_filter ebtables ip6table_filter ip6_tables rpcrdma ib_isert iscsi_target_mod sunrpc ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm intel_rapl sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel intel_cstate iTCO_wdt iTCO_vendor_support intel_uncore ib_core intel_rapl_perf mei_me mei joydev i2c_i801 lpc_ich ioatdma shpchp wmi sch_fq_codel xfs libcrc32c mgag200 ixgbe drm_kms_helper isci ttm firewire_ohci
   kernel:  mdio drm igb libsas crc32c_intel firewire_core ptp pps_core scsi_transport_sas crc_itu_t dca i2c_algo_bit ipmi_si ipmi_devintf ipmi_msghandler [last unloaded: i40e]
   kernel: CPU: 10 PID: 4219 Comm: ip Tainted: G           OE    4.16.13custom-fq-codel-test+ #3
   kernel: Hardware name: Intel Corporation S2600CO/S2600CO, BIOS SE5C600.86B.02.05.0004.051120151007 05/11/2015
   kernel: RIP: 0010:fq_codel_reset+0x58/0xd0 [sch_fq_codel]
   kernel: RSP: 0018:ffffbfbf4c1fb620 EFLAGS: 00010246
   kernel: RAX: 0000000000000400 RBX: 0000000000000000 RCX: 00000000000005b9
   kernel: RDX: 0000000000000000 RSI: ffff9d03264a60c0 RDI: ffff9cfd17b31c00
   kernel: RBP: 0000000000000001 R08: 00000000000260c0 R09: ffffffffb679c3e9
   kernel: R10: fffff1dab06a0e80 R11: ffff9cfd163af800 R12: ffff9cfd17b31c00
   kernel: R13: 0000000000000001 R14: ffff9cfd153de600 R15: 0000000000000001
   kernel: FS:  00007fdec2f92800(0000) GS:ffff9d0326480000(0000) knlGS:0000000000000000
   kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   kernel: CR2: 0000000000000008 CR3: 0000000c1956a006 CR4: 00000000000606e0
   kernel: Call Trace:
   kernel:  qdisc_destroy+0x56/0x140
   kernel:  qdisc_create_dflt+0x8b/0xb0
   kernel:  mq_init+0xc1/0xf0
   kernel:  qdisc_create_dflt+0x5a/0xb0
   kernel:  dev_activate+0x205/0x230
   kernel:  __dev_open+0xf5/0x160
   kernel:  __dev_change_flags+0x1a3/0x210
   kernel:  dev_change_flags+0x21/0x60
   kernel:  do_setlink+0x660/0xdf0
   kernel:  ? down_trylock+0x25/0x30
   kernel:  ? xfs_buf_trylock+0x1a/0xd0 [xfs]
   kernel:  ? rtnl_newlink+0x816/0x990
   kernel:  ? _xfs_buf_find+0x327/0x580 [xfs]
   kernel:  ? _cond_resched+0x15/0x30
   kernel:  ? kmem_cache_alloc+0x20/0x1b0
   kernel:  ? rtnetlink_rcv_msg+0x200/0x2f0
   kernel:  ? rtnl_calcit.isra.30+0x100/0x100
   kernel:  ? netlink_rcv_skb+0x4c/0x120
   kernel:  ? netlink_unicast+0x19e/0x260
   kernel:  ? netlink_sendmsg+0x1ff/0x3c0
   kernel:  ? sock_sendmsg+0x36/0x40
   kernel:  ? ___sys_sendmsg+0x295/0x2f0
   kernel:  ? ebitmap_cmp+0x6d/0x90
   kernel:  ? dev_get_by_name_rcu+0x73/0x90
   kernel:  ? skb_dequeue+0x52/0x60
   kernel:  ? __inode_wait_for_writeback+0x7f/0xf0
   kernel:  ? bit_waitqueue+0x30/0x30
   kernel:  ? fsnotify_grab_connector+0x3c/0x60
   kernel:  ? __sys_sendmsg+0x51/0x90
   kernel:  ? do_syscall_64+0x74/0x180
   kernel:  ? entry_SYSCALL_64_after_hwframe+0x3d/0xa2
   kernel: Code: 00 00 48 89 87 00 02 00 00 8b 87 a0 01 00 00 85 c0 0f 84 84 00 00 00 31 ed 48 63 dd 83 c5 01 48 c1 e3 06 49 03 9c 24 90 01 00 00 <48> 8b 73 08 48 8b 3b e8 6c 9a 4f f6 48 8d 43 10 48 c7 03 00 00
   kernel: RIP: fq_codel_reset+0x58/0xd0 [sch_fq_codel] RSP: ffffbfbf4c1fb620
   kernel: CR2: 0000000000000008
   kernel: ---[ end trace e81a62bede66274e ]---

This is caused because flows_cnt is non-zero, but flows hasn't been
initialized. fq_codel_init has left the private data in a partially
initialized state.

To fix this, reset flows_cnt to 0 when we fail to initialize.
Additionally, to make the state more consistent, also cleanup the flows
pointer when the allocation of backlogs fails.

This fixes the NULL pointer dereference, since both the for-loop and
memset in fq_codel_reset will be no-ops when flow_cnt is zero.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 12:32:09 -07:00
Kees Cook
778e1cdd81 treewide: kvzalloc() -> kvcalloc()
The kvzalloc() function has a 2-factor argument form, kvcalloc(). This
patch replaces cases of:

        kvzalloc(a * b, gfp)

with:
        kvcalloc(a * b, gfp)

as well as handling cases of:

        kvzalloc(a * b * c, gfp)

with:

        kvzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kvcalloc(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kvzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kvzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kvzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kvzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kvzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kvzalloc
+ kvcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kvzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kvzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kvzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kvzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kvzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kvzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kvzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kvzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kvzalloc(C1 * C2 * C3, ...)
|
  kvzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kvzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kvzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kvzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kvzalloc(sizeof(THING) * C2, ...)
|
  kvzalloc(sizeof(TYPE) * C2, ...)
|
  kvzalloc(C1 * C2 * C3, ...)
|
  kvzalloc(C1 * C2, ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kvzalloc
+ kvcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Alexander Aring
8d1a77f974 net: sch: api: add extack support in tcf_block_get
This patch adds extack support for the function tcf_block_get which is
a common used function in the tc subsystem. Callers which are interested
in the receiving error can assign extack to get a more detailed
information why tcf_block_get failed.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:51 -05:00
Alexander Aring
cbaacc4e8a net: sched: sch: add extack for block callback
This patch adds extack support for block callback to prepare per-qdisc
specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
Alexander Aring
793d81d6a1 net: sched: sch: add extack to change class
This patch adds extack support for class change callback api. This prepares
to handle extack support inside each specific class implementation.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
Alexander Aring
2030721cc0 net: sched: sch: add extack for change qdisc ops
This patch adds extack support for change callback for qdisc ops
structtur to prepare per-qdisc specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
Alexander Aring
e63d7dfd2d net: sched: sch: add extack for init callback
This patch adds extack support for init callback to prepare per-qdisc
specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21 12:32:50 -05:00
Gustavo A. R. Silva
f3ae608edb net: sched: mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22 02:07:08 +01:00
Jiri Pirko
69d78ef25c net: sched: store Qdisc pointer in struct block
Prepare for removal of tp->q and store Qdisc pointer in the block
structure.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 21:00:40 +01:00
David S. Miller
6026e043d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 17:42:05 -07:00
Nikolay Aleksandrov
30c31d746d sch_fq_codel: avoid double free on init failure
It is very unlikely to happen but the backlogs memory allocation
could fail and will free q->flows, but then ->destroy() will free
q->flows too. For correctness remove the first free and let ->destroy
clean up.

Fixes: 87b60cfacf ("net_sched: fix error recovery at qdisc creation")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-30 15:26:11 -07:00
WANG Cong
143976ce99 net_sched: remove tc class reference counting
For TC classes, their ->get() and ->put() are always paired, and the
reference counting is completely useless, because:

1) For class modification and dumping paths, we already hold RTNL lock,
   so all of these ->get(),->change(),->put() are atomic.

2) For filter bindiing/unbinding, we use other reference counter than
   this one, and they should have RTNL lock too.

3) For ->qlen_notify(), it is special because it is called on ->enqueue()
   path, but we already hold qdisc tree lock there, and we hold this
   tree lock when graft or delete the class too, so it should not be gone
   or changed until we release the tree lock.

Therefore, this patch removes ->get() and ->put(), but:

1) Adds a new ->find() to find the pointer to a class by classid, no
   refcnt.

2) Move the original class destroy upon the last refcnt into ->delete(),
   right after releasing tree lock. This is fine because the class is
   already removed from hash when holding the lock.

For those who also use ->put() as ->unbind(), just rename them to reflect
this change.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25 17:19:10 -07:00
Jiri Pirko
e25ea21ffa net: sched: introduce a TRAP control action
There is need to instruct the HW offloaded path to push certain matched
packets to cpu/kernel for further analysis. So this patch introduces a
new TRAP control action to TC.

For kernel datapath, this action does not make much sense. So with the
same logic as in HW, new TRAP behaves similar to STOLEN. The skb is just
dropped in the datapath (and virtually ejected to an upper level, which
does not exist in case of kernel).

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Yotam Gigi <yotamg@mellanox.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06 12:45:23 -04:00
Jiri Pirko
6529eaba33 net: sched: introduce tcf block infractructure
Currently, the filter chains are direcly put into the private structures
of qdiscs. In order to be able to have multiple chains per qdisc and to
allow filter chains sharing among qdiscs, there is a need for common
object that would hold the chains. This introduces such object and calls
it "tcf_block".

Helpers to get and put the blocks are provided to be called from
individual qdisc code. Also, the original filter_list pointers are left
in qdisc privs to allow the entry into tcf_block processing without any
added overhead of possible multiple pointer dereference on fast path.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17 15:22:13 -04:00
Jiri Pirko
87d83093bf net: sched: move tc_classify function to cls_api.c
Move tc_classify function to cls_api.c where it belongs, rename it to
fit the namespace.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17 15:22:13 -04:00
Michal Hocko
752ade68cb treewide: use kv[mz]alloc* rather than opencoded variants
There are many code paths opencoding kvmalloc.  Let's use the helper
instead.  The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator.  E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation.  This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously.  There is no guarantee something like that happens
though.

This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.

Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Santosh Raspatur <santosh@chelsio.com>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Yishai Hadas <yishaih@mellanox.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:13 -07:00
Johannes Berg
fceb6435e8 netlink: pass extended ACK struct to parsing functions
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13 13:58:22 -04:00
Or Gerlitz
a5e6a3b022 net/sched: fq_codel: Avoid set-but-unused variable
The code introduced by commit 2ccccf5fb4 ("net_sched: update
hierarchical backlog too") only sets prev_backlog in fq_codel_dequeue()
but not using that anywhere, remove that setting.

Cc: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-16 12:02:14 -07:00
Jiri Pirko
cf1facda2f sched: move tcf_proto_destroy and tcf_destroy_chain helpers into cls_api
Creation is done in this file, move destruction to be at the same place.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-10 11:38:08 -05:00
Andrew Collins
264b87fa61 fq_codel: Avoid regenerating skb flow hash unless necessary
The fq_codel qdisc currently always regenerates the skb flow hash.
This wastes some cycles and prevents flow seperation in cases where
the traffic has been encrypted and can no longer be understood by the
flow dissector.

Change it to use the prexisting flow hash if one exists, and only
regenerate if necessary.

Signed-off-by: Andrew Collins <acollins@cradlepoint.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-20 12:15:14 -05:00
Eric Dumazet
008830bc32 net_sched: fq_codel: cache skb->truesize into skb->cb
Now we defer skb drops, it makes sense to keep a copy
of skb->truesize in struct codel_skb_cb to avoid one
cache line miss per dropped skb in fq_codel_drop(),
to reduce latencies a bit further.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25 12:19:35 -04:00
Eric Dumazet
520ac30f45 net_sched: drop packets after root qdisc lock is released
Qdisc performance suffers when packets are dropped at enqueue()
time because drops (kfree_skb()) are done while qdisc lock is held,
delaying a dequeue() draining the queue.

Nominal throughput can be reduced by 50 % when this happens,
at a time we would like the dequeue() to proceed as fast as possible.

Even FQ is vulnerable to this problem, while one of FQ goals was
to provide some flow isolation.

This patch adds a 'struct sk_buff **to_free' parameter to all
qdisc->enqueue(), and in qdisc_drop() helper.

I measured a performance increase of up to 12 %, but this patch
is a prereq so that future batches in enqueue() can fly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25 12:19:35 -04:00
Eric Dumazet
ece5d4c723 net_sched: fq_codel: defer skb freeing
Both fq_codel_change() and fq_codel_reset() can use rtnl_kfree_skbs()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 14:08:35 -07:00
David S. Miller
1578b0a5e9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/sched/act_police.c
	net/sched/sch_drr.c
	net/sched/sch_hfsc.c
	net/sched/sch_prio.c
	net/sched/sch_red.c
	net/sched/sch_tbf.c

In net-next the drop methods of the packet schedulers got removed, so
the bug fixes to them in 'net' are irrelevant.

A packet action unload crash fix conflicts with the addition of the
new firstuse timestamp.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10 11:52:24 -07:00
Florian Westphal
a09ceb0e08 sched: remove qdisc->drop
after removal of TCA_CBQ_OVL_STRATEGY from cbq scheduler, there are no
more callers of ->drop() outside of other ->drop functions, i.e.
nothing calls them.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 23:58:52 -07:00
Eric Dumazet
edb09eb17e net: sched: do not acquire qdisc spinlock in qdisc/class stats dump
Large tc dumps (tc -s {qdisc|class} sh dev ethX) done by Google BwE host
agent [1] are problematic at scale :

For each qdisc/class found in the dump, we currently lock the root qdisc
spinlock in order to get stats. Sampling stats every 5 seconds from
thousands of HTB classes is a challenge when the root qdisc spinlock is
under high pressure. Not only the dumps take time, they also slow
down the fast path (queue/dequeue packets) by 10 % to 20 % in some cases.

An audit of existing qdiscs showed that sch_fq_codel is the only qdisc
that might need the qdisc lock in fq_codel_dump_stats() and
fq_codel_dump_class_stats()

In v2 of this patch, I now use the Qdisc running seqcount to provide
consistent reads of packets/bytes counters, regardless of 32/64 bit arches.

I also changed rate estimators to use the same infrastructure
so that they no longer need to lock root qdisc lock.

[1]
http://static.googleusercontent.com/media/research.google.com/en//pubs/archive/43838.pdf

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Kevin Athey <kda@google.com>
Cc: Xiaotian Pei <xiaotian@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:37:14 -07:00
Eric Dumazet
aafddbf0cf fq_codel: return non zero qlen in class dumps
We properly scan the flow list to count number of packets,
but John passed 0 to gnet_stats_copy_queue() so we report
a zero value to user space instead of the result.

Fixes: 6401585366 ("net: sched: restrict use of qstats qlen")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:28:11 -07:00
Eric Dumazet
80e509db54 fq_codel: fix NET_XMIT_CN behavior
My prior attempt to fix the backlogs of parents failed.

If we return NET_XMIT_CN, our parents wont increase their backlog,
so our qdisc_tree_reduce_backlog() should take this into account.

v2: Florian Westphal pointed out that we could drop the packet,
so we need to save qdisc_pkt_len(skb) in a temp variable before
calling fq_codel_drop()

Fixes: 9d18562a22 ("fq_codel: add batch ability to fq_codel_drop()")
Fixes: 2ccccf5fb4 ("net_sched: update hierarchical backlog too")
Reported-by: Stas Nichiporovich <stasn77@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 14:49:56 -07:00
Eric Dumazet
77f5776146 fq_codel: fix memory limitation drift
memory_usage must be decreased in dequeue_func(), not in
fq_codel_dequeue(), otherwise packets dropped by Codel algo
are missing this decrease.

Also we need to clear memory_usage in fq_codel_reset()

Fixes: 95b58430ab ("fq_codel: add memory limitation per queue")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-16 21:54:24 -04:00
Eric Dumazet
95b58430ab fq_codel: add memory limitation per queue
On small embedded routers, one wants to control maximal amount of
memory used by fq_codel, instead of controlling number of packets or
bytes, since GRO/TSO make these not practical.

Assuming skb->truesize is accurate, we have to keep track of
skb->truesize sum for skbs in queue.

This patch adds a new TCA_FQ_CODEL_MEMORY_LIMIT attribute.

I chose a default value of 32 MBytes, which looks reasonable even
for heavy duty usages. (Prior fq_codel users should not be hurt
when they upgrade their kernels)

Two fields are added to tc_fq_codel_qd_stats to report :
 - Current memory usage
 - Number of drops caused by memory limits

# tc qd replace dev eth1 root est 1sec 4sec fq_codel memory_limit 4M
..
# tc -s -d qd sh dev eth1
qdisc fq_codel 8008: root refcnt 257 limit 10240p flows 1024
 quantum 1514 target 5.0ms interval 100.0ms memory_limit 4Mb ecn
 Sent 2083566791363 bytes 1376214889 pkt (dropped 4994406, overlimits 0
requeues 21705223)
 rate 9841Mbit 812549pps backlog 3906120b 376p requeues 21705223
  maxpacket 68130 drop_overlimit 4994406 new_flow_count 28855414
  ecn_mark 0 memory_used 4190048 drop_overmemory 4994406
  new_flows_len 1 old_flows_len 177

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Dave Täht <dave.taht@gmail.com>
Cc: Sebastian Möller <moeller0@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-08 23:49:38 -04:00
Eric Dumazet
9d18562a22 fq_codel: add batch ability to fq_codel_drop()
In presence of inelastic flows and stress, we can call
fq_codel_drop() for every packet entering fq_codel qdisc.

fq_codel_drop() is quite expensive, as it does a linear scan
of 4 KB of memory to find a fat flow.
Once found, it drops the oldest packet of this flow.

Instead of dropping a single packet, try to drop 50% of the backlog
of this fat flow, with a configurable limit of 64 packets per round.

TCA_FQ_CODEL_DROP_BATCH_SIZE is the new attribute to make this
limit configurable.

With this strategy the 4 KB search is amortized to a single cache line
per drop [1], so fq_codel_drop() no longer appears at the top of kernel
profile in presence of few inelastic flows.

[1] Assuming a 64byte cache line, and 1024 buckets

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dave Taht <dave.taht@gmail.com>
Cc: Jonathan Morton <chromatix99@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Dave Taht
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-03 12:47:09 -04:00
Michal Kazior
d068ca2ae2 codel: split into multiple files
It was impossible to include codel.h for the
purpose of having access to codel_params or
codel_vars structure definitions and using them
for embedding in other more complex structures.

This splits allows codel.h itself to be treated
like any other header file while codel_qdisc.h and
codel_impl.h contain function definitions with
logic that was previously in codel.h.

This copies over copyrights and doesn't involve
code changes other than adding a few additional
include directives to net/sched/sch*codel.c.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-25 16:44:27 -04:00
Michal Kazior
79bdc4c862 codel: generalize the implementation
This strips out qdisc specific bits from the code
and makes it slightly more reusable. Codel will be
used by wireless/mac80211 in the future.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-25 16:44:27 -04:00
WANG Cong
2ccccf5fb4 net_sched: update hierarchical backlog too
When the bottom qdisc decides to, for example, drop some packet,
it calls qdisc_tree_decrease_qlen() to update the queue length
for all its ancestors, we need to update the backlog too to
keep the stats on root qdisc accurate.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-29 17:02:33 -05:00
Daniel Borkmann
3b3ae88026 net: sched: consolidate tc_classify{,_compat}
For classifiers getting invoked via tc_classify(), we always need an
extra function call into tc_classify_compat(), as both are being
exported as symbols and tc_classify() itself doesn't do much except
handling of reclassifications when tp->classify() returned with
TC_ACT_RECLASSIFY.

CBQ and ATM are the only qdiscs that directly call into tc_classify_compat(),
all others use tc_classify(). When tc actions are being configured
out in the kernel, tc_classify() effectively does nothing besides
delegating.

We could spare this layer and consolidate both functions. pktgen on
single CPU constantly pushing skbs directly into the netif_receive_skb()
path with a dummy classifier on ingress qdisc attached, improves
slightly from 22.3Mpps to 23.1Mpps.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27 14:18:48 -07:00
Eric Dumazet
3d0e0af406 fq_codel: explicitly reset flows in ->reset()
Alex reported the following crash when using fq_codel
with htb:

  crash> bt
  PID: 630839  TASK: ffff8823c990d280  CPU: 14  COMMAND: "tc"
   [... snip ...]
   #8 [ffff8820ceec17a0] page_fault at ffffffff8160a8c2
      [exception RIP: htb_qlen_notify+24]
      RIP: ffffffffa0841718  RSP: ffff8820ceec1858  RFLAGS: 00010282
      RAX: 0000000000000000  RBX: 0000000000000000  RCX: ffff88241747b400
      RDX: ffff88241747b408  RSI: 0000000000000000  RDI: ffff8811fb27d000
      RBP: ffff8820ceec1868   R8: ffff88120cdeff24   R9: ffff88120cdeff30
      R10: 0000000000000bd4  R11: ffffffffa0840919  R12: ffffffffa0843340
      R13: 0000000000000000  R14: 0000000000000001  R15: ffff8808dae5c2e8
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #9 [...] qdisc_tree_decrease_qlen at ffffffff81565375
  #10 [...] fq_codel_dequeue at ffffffffa084e0a0 [sch_fq_codel]
  #11 [...] fq_codel_reset at ffffffffa084e2f8 [sch_fq_codel]
  #12 [...] qdisc_destroy at ffffffff81560d2d
  #13 [...] htb_destroy_class at ffffffffa08408f8 [sch_htb]
  #14 [...] htb_put at ffffffffa084095c [sch_htb]
  #15 [...] tc_ctl_tclass at ffffffff815645a3
  #16 [...] rtnetlink_rcv_msg at ffffffff81552cb0
  [... snip ...]

As Jamal pointed out, there is actually no need to call dequeue
to purge the queued skb's in reset, data structures can be just
reset explicitly. Therefore, we reset everything except config's
and stats, so that we would have a fresh start after device flipping.

Fixes: 4b549a2ef4 ("fq_codel: Fair Queue Codel AQM")
Reported-by: Alex Gartrell <agartrell@fb.com>
Cc: Alex Gartrell <agartrell@fb.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
[xiyou.wangcong@gmail.com: added codel_vars_init() and qdisc_qstats_backlog_dec()]
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-02 17:20:01 -07:00
WANG Cong
c0afd9ce4d fq_codel: fix return value of fq_codel_drop()
The ->drop() is supposed to return the number of bytes it dropped,
however fq_codel_drop() returns the index of the flow where it drops
a packet from.

Fix this by introducing a helper to wrap fq_codel_drop().

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 21:36:35 -07:00
WANG Cong
052cbda41f fq_codel: fix a use-after-free
Fixes: 25331d6ce4 ("net: sched: implement qstat helper routines")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 17:18:21 -07:00
David S. Miller
b04096ff33 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Four minor merge conflicts:

1) qca_spi.c renamed the local variable used for the SPI device
   from spi_device to spi, meanwhile the spi_set_drvdata() call
   got moved further up in the probe function.

2) Two changes were both adding new members to codel params
   structure, and thus we had overlapping changes to the
   initializer function.

3) 'net' was making a fix to sk_release_kernel() which is
   completely removed in 'net-next'.

4) In net_namespace.c, the rtnl_net_fill() call for GET operations
   had the command value fixed, meanwhile 'net-next' adjusted the
   argument signature a bit.

This also matches example merge resolutions posted by Stephen
Rothwell over the past two days.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 14:31:43 -04:00
Eric Dumazet
80ba92fa1a codel: add ce_threshold attribute
For DCTCP or similar ECN based deployments on fabrics with shallow
buffers, hosts are responsible for a good part of the buffering.

This patch adds an optional ce_threshold to codel & fq_codel qdiscs,
so that DCTCP can have feedback from queuing in the host.

A DCTCP enabled egress port simply have a queue occupancy threshold
above which ECT packets get CE mark.

In codel language this translates to a sojourn time, so that one doesn't
have to worry about bytes or bandwidth but delays.

This makes the host an active participant in the health of the whole
network.

This also helps experimenting DCTCP in a setup without DCTCP compliant
fabric.

On following example, ce_threshold is set to 1ms, and we can see from
'ldelay xxx us' that TCP is not trying to go around the 5ms codel
target.

Queue has more capacity to absorb inelastic bursts (say from UDP
traffic), as queues are maintained to an optimal level.

lpaa23:~# ./tc -s -d qd sh dev eth1
qdisc mq 1: dev eth1 root
 Sent 87910654696 bytes 58065331 pkt (dropped 0, overlimits 0 requeues 42961)
 backlog 3108242b 364p requeues 42961
qdisc codel 8063: dev eth1 parent 1:1 limit 1000p target 5.0ms ce_threshold 1.0ms interval 100.0ms
 Sent 7363778701 bytes 4863809 pkt (dropped 0, overlimits 0 requeues 5503)
 rate 2348Mbit 193919pps backlog 255866b 46p requeues 5503
  count 0 lastcount 0 ldelay 1.0ms drop_next 0us
  maxpacket 68130 ecn_mark 0 drop_overlimit 0 ce_mark 72384
qdisc codel 8064: dev eth1 parent 1:2 limit 1000p target 5.0ms ce_threshold 1.0ms interval 100.0ms
 Sent 7636486190 bytes 5043942 pkt (dropped 0, overlimits 0 requeues 5186)
 rate 2319Mbit 191538pps backlog 207418b 64p requeues 5186
  count 0 lastcount 0 ldelay 694us drop_next 0us
  maxpacket 68130 ecn_mark 0 drop_overlimit 0 ce_mark 69873
qdisc codel 8065: dev eth1 parent 1:3 limit 1000p target 5.0ms ce_threshold 1.0ms interval 100.0ms
 Sent 11569360142 bytes 7641602 pkt (dropped 0, overlimits 0 requeues 5554)
 rate 3041Mbit 251096pps backlog 210446b 59p requeues 5554
  count 0 lastcount 0 ldelay 889us drop_next 0us
  maxpacket 68130 ecn_mark 0 drop_overlimit 0 ce_mark 37780
...

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Glenn Judd <glenn.judd@morganstanley.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-10 19:50:20 -04:00
Tom Herbert
342db22182 sched: Call skb_get_hash_perturb in sch_fq_codel
Call skb_get_hash_perturb instead of doing skb_flow_dissect and then
jhash by hand.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-04 00:09:08 -04:00
Eric Dumazet
a5d2809040 codel: fix maxpacket/mtu confusion
Under presence of TSO/GSO/GRO packets, codel at low rates can be quite
useless. In following example, not a single packet was ever dropped,
while average delay in codel queue is ~100 ms !

qdisc codel 0: parent 1:12 limit 16000p target 5.0ms interval 100.0ms
 Sent 134376498 bytes 88797 pkt (dropped 0, overlimits 0 requeues 0)
 backlog 13626b 3p requeues 0
  count 0 lastcount 0 ldelay 96.9ms drop_next 0us
  maxpacket 9084 ecn_mark 0 drop_overlimit 0

This comes from a confusion of what should be the minimal backlog. It is
pretty clear it is not 64KB or whatever max GSO packet ever reached the
qdisc.

codel intent was to use MTU of the device.

After the fix, we finally drop some packets, and rtt/cwnd of my single
TCP flow are meeting our expectations.

qdisc codel 0: parent 1:12 limit 16000p target 5.0ms interval 100.0ms
 Sent 102798497 bytes 67912 pkt (dropped 1365, overlimits 0 requeues 0)
 backlog 6056b 3p requeues 0
  count 1 lastcount 1 ldelay 36.3ms drop_next 0us
  maxpacket 10598 ecn_mark 0 drop_overlimit 0

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kathleen Nichols <nichols@pollere.com>
Cc: Dave Taht <dave.taht@gmail.com>
Cc: Van Jacobson <vanj@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-03 22:17:40 -04:00
Valdis.Kletnieks@vt.edu
69204cf7eb net: fix suspicious rcu_dereference_check in net/sched/sch_fq_codel.c
commit 46e5da40ae (net: qdisc: use rcu prefix and silence
 sparse warnings) triggers a spurious warning:

net/sched/sch_fq_codel.c:97 suspicious rcu_dereference_check() usage!

The code should be using the _bh variant of rcu_dereference.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09 21:49:09 -05:00
John Fastabend
b0ab6f9275 net: sched: enable per cpu qstats
After previous patches to simplify qstats the qstats can be
made per cpu with a packed union in Qdisc struct.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30 01:02:26 -04:00
John Fastabend
6401585366 net: sched: restrict use of qstats qlen
This removes the use of qstats->qlen variable from the classifiers
and makes it an explicit argument to gnet_stats_copy_queue().

The qlen represents the qdisc queue length and is packed into
the qstats at the last moment before passnig to user space. By
handling it explicitely we avoid, in the percpu stats case, having
to figure out which per_cpu variable to put it in.

It would probably be best to remove it from qstats completely
but qstats is a user space ABI and can't be broken. A future
patch could make an internal only qstats structure that would
avoid having to allocate an additional u32 variable on the
Qdisc struct. This would make the qstats struct 128bits instead
of 128+32.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30 01:02:26 -04:00
John Fastabend
25331d6ce4 net: sched: implement qstat helper routines
This adds helpers to manipulate qstats logic and replaces locations
that touch the counters directly. This simplifies future patches
to push qstats onto per cpu counters.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30 01:02:26 -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
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
WANG Cong
4cb28970a2 net: use the new API kvfree()
It is available since v3.15-rc5.

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-05 00:49:51 -07:00