linux-stable.git/net/core/gen_stats.c, branch linux-4.8.y Linux kernel stable tree Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-06-10T18:52:24+00:00 David S. Miller davem@davemloft.net 2016-06-10T18:52:24+00:00 1578b0a5e92825334760741e5c166b8873886f1b 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> 
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>
net: sched: fix missing doc annotations 2016-06-08T18:20:40+00:00 Eric Dumazet edumazet@google.com 2016-06-08T14:22:49+00:00 123b36526592f009bf8eccb7c8833aeda296d9cf "make htmldocs" complains otherwise: .//net/core/gen_stats.c:168: warning: No description found for parameter 'running' .//include/linux/netdevice.h:1867: warning: No description found for parameter 'qdisc_running_key' Fixes: f9eb8aea2a1e ("net_sched: transform qdisc running bit into a seqcount") Fixes: edb09eb17ed8 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
"make htmldocs" complains otherwise:

.//net/core/gen_stats.c:168: warning: No description found for parameter 'running'
.//include/linux/netdevice.h:1867: warning: No description found for parameter 'qdisc_running_key'

Fixes: f9eb8aea2a1e ("net_sched: transform qdisc running bit into a seqcount")
Fixes: edb09eb17ed8 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net_sched: add missing paddattr description 2016-06-08T18:17:39+00:00 Eric Dumazet edumazet@google.com 2016-06-08T13:19:45+00:00 e0d194adfa9f5f473068cc546bee60fb84ab77ba "make htmldocs" complains otherwise: .//net/core/gen_stats.c:65: warning: No description found for parameter 'padattr' .//net/core/gen_stats.c:101: warning: No description found for parameter 'padattr' Fixes: 9854518ea04d ("sched: align nlattr properly when needed") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: kbuild test robot <fengguang.wu@intel.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
"make htmldocs" complains otherwise:

.//net/core/gen_stats.c:65: warning: No description found for parameter 'padattr'
.//net/core/gen_stats.c:101: warning: No description found for parameter 'padattr'

Fixes: 9854518ea04d ("sched: align nlattr properly when needed")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: sched: do not acquire qdisc spinlock in qdisc/class stats dump 2016-06-07T23:37:14+00:00 Eric Dumazet edumazet@google.com 2016-06-06T16:37:16+00:00 edb09eb17ed89eaa82a52dd306beac93e292b485 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> 
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>
sched: align nlattr properly when needed 2016-04-26T16:00:49+00:00 Nicolas Dichtel nicolas.dichtel@6wind.com 2016-04-26T08:06:18+00:00 9854518ea04db33738602d45ebc96a200e6f5198 Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
gen_stats.c: Add description for cpu argument 2016-03-20T20:48:06+00:00 Luis de Bethencourt luisbg@osg.samsung.com 2016-03-19T21:19:55+00:00 b002fdcc89979ff342d4139d165a4e1d51e586ff Function gnet_stats_copy_basic is missing the description of the cpu argument in the documentation. Adding it. Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Function gnet_stats_copy_basic is missing the description of the cpu
argument in the documentation. Adding it.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
gen_stats.c: Duplicate xstats buffer for later use 2015-02-19T20:45:53+00:00 Ignacy Gawędzki ignacy.gawedzki@green-communications.fr 2015-02-13T22:47:05+00:00 1c4cff0cf55011792125b6041bc4e9713e46240f The gnet_stats_copy_app() function gets called, more often than not, with its second argument a pointer to an automatic variable in the caller's stack. Therefore, to avoid copying garbage afterwards when calling gnet_stats_finish_copy(), this data is better copied to a dynamically allocated memory that gets freed after use. [xiyou.wangcong@gmail.com: remove a useless kfree()] Signed-off-by: Ignacy Gawędzki <ignacy.gawedzki@green-communications.fr> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
The gnet_stats_copy_app() function gets called, more often than not, with its
second argument a pointer to an automatic variable in the caller's stack.
Therefore, to avoid copying garbage afterwards when calling
gnet_stats_finish_copy(), this data is better copied to a dynamically allocated
memory that gets freed after use.

[xiyou.wangcong@gmail.com: remove a useless kfree()]

Signed-off-by: Ignacy Gawędzki <ignacy.gawedzki@green-communications.fr>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net_sched: fix unused variables in __gnet_stats_copy_basic_cpu() 2014-10-07T04:10:49+00:00 WANG Cong xiyou.wangcong@gmail.com 2014-10-07T00:01:33+00:00 02c0fc1b8f41e6e895d6573615ba8ff549b685d2 Probably not a big deal, but we'd better just use the one we get in retry loop. Fixes: commit 22e0f8b9322cb1a48b1357e8 ("net: sched: make bstats per cpu and estimator RCU safe") Reported-by: Joe Perches <joe@perches.com> 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> 
Probably not a big deal, but we'd better just use the
one we get in retry loop.

Fixes: commit 22e0f8b9322cb1a48b1357e8 ("net: sched: make bstats per cpu and estimator RCU safe")
Reported-by: Joe Perches <joe@perches.com>
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>
net: sched: enable per cpu qstats 2014-09-30T05:02:26+00:00 John Fastabend john.fastabend@gmail.com 2014-09-28T18:54:24+00:00 b0ab6f92752b9f9d8da980506e9df3bd9dcd7ed3 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> 
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>
net: sched: restrict use of qstats qlen 2014-09-30T05:02:26+00:00 John Fastabend john.fastabend@gmail.com 2014-09-28T18:53:57+00:00 6401585366326fc0ecbc372ec60d1a15cd8be2f5 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> 
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>