Skip to content

L
linux
Switch branch/tag
  1. 09 Oct, 2017 17 commits
  3. 08 Oct, 2017 7 commits
  5. 07 Oct, 2017 16 commits
    • David S. Miller's avatar
      Merge branch 'bpf-obj-name-misc' · c9f766bc
      David S. Miller authored 
      Martin KaFai Lau says:

====================
bpf: Misc improvements and a new usage on bpf obj name

The first two patches make improvements on the bpf obj name.

The last patch adds the prog name to kallsyms.
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c9f766bc
    • Martin KaFai Lau's avatar
      bpf: Append prog->aux->name in bpf_get_prog_name() · 368211fb
      Martin KaFai Lau authored 
      This patch makes the bpf_prog's name available
in kallsyms.

The new format is bpf_prog_tag[_name].

Sample kallsyms from running selftests/bpf/test_progs:
[root@arch-fb-vm1 ~]# egrep ' bpf_prog_[0-9a-fA-F]{16}' /proc/kallsyms
ffffffffa0048000 t bpf_prog_dabf0207d1992486_test_obj_id
ffffffffa0038000 t bpf_prog_a04f5eef06a7f555__123456789ABCDE
ffffffffa0050000 t bpf_prog_a04f5eef06a7f555
Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarAlexei Starovoitov <ast@fb.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      368211fb
    • Martin KaFai Lau's avatar
      bpf: Use char in prog and map name · 067cae47
      Martin KaFai Lau authored 
      Instead of u8, use char for prog and map name.  It can avoid the
userspace tool getting compiler's signess warning.  The
bpf_prog_aux, bpf_map, bpf_attr, bpf_prog_info and
bpf_map_info are changed.
Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarAlexei Starovoitov <ast@fb.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      067cae47
    • Martin KaFai Lau's avatar
      bpf: Change bpf_obj_name_cpy() to better ensure map's name is init by 0 · 473d9734
      Martin KaFai Lau authored 
      During get_info_by_fd, the prog/map name is memcpy-ed.  It depends
on the prog->aux->name and map->name to be zero initialized.

bpf_prog_aux is easy to guarantee that aux->name is zero init.

The name in bpf_map may be harder to be guaranteed in the future when
new map type is added.

Hence, this patch makes bpf_obj_name_cpy() to always zero init
the prog/map name.
Suggested-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      473d9734
    • William Tu's avatar
      ip_gre: check packet length and mtu correctly in erspan tx · f192970d
      William Tu authored 
      Similarly to early patch for erspan_xmit(), the ARPHDR_ETHER device
is the length of the whole ether packet.  So skb->len should subtract
the dev->hard_header_len.

Fixes: 1a66a836 ("gre: add collect_md mode to ERSPAN tunnel")
Fixes: 84e54fe0 ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: default avatarWilliam Tu <u9012063@gmail.com>
Cc: Xin Long <lucien.xin@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Reviewed-by: default avatarXin Long <lucien.xin@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f192970d
    • Lin Zhang's avatar
      net: phonet: mark phonet_protocol as const · 548ec114
      Lin Zhang authored 
      The phonet_protocol structs don't need to be written by anyone and
so can be marked as const.
Signed-off-by: default avatarLin Zhang <xiaolou4617@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      548ec114
    • Lin Zhang's avatar
      net: phonet: mark header_ops as const · 64237470
      Lin Zhang authored 
      Signed-off-by: default avatarLin Zhang <xiaolou4617@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      64237470
    • David S. Miller's avatar
      Merge branch 'bpf-perf-time-helpers' · a1d753d2
      David S. Miller authored 
      Yonghong Song says:

====================
bpf: add two helpers to read perf event enabled/running time

Hardware pmu counters are limited resources. When there are more
pmu based perf events opened than available counters, kernel will
multiplex these events so each event gets certain percentage
(but not 100%) of the pmu time. In case that multiplexing happens,
the number of samples or counter value will not reflect the
case compared to no multiplexing. This makes comparison between
different runs difficult.

Typically, the number of samples or counter value should be
normalized before comparing to other experiments. The typical
normalization is done like:
  normalized_num_samples = num_samples * time_enabled / time_running
  normalized_counter_value = counter_value * time_enabled / time_running
where time_enabled is the time enabled for event and time_running is
the time running for event since last normalization.

This patch set implements two helper functions.
The helper bpf_perf_event_read_value reads counter/time_enabled/time_running
for perf event array map. The helper bpf_perf_prog_read_value read
counter/time_enabled/time_running for bpf prog with type BPF_PROG_TYPE_PERF_EVENT.
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a1d753d2
    • Yonghong Song's avatar
      bpf: add a test case for helper bpf_perf_prog_read_value · 81b9cf80
      Yonghong Song authored 
      The bpf sample program trace_event is enhanced to use the new
helper to print out enabled/running time.
Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Acked-by: default avatarAlexei Starovoitov <ast@fb.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      81b9cf80
    • Yonghong Song's avatar
      bpf: add helper bpf_perf_prog_read_value · 4bebdc7a
      Yonghong Song authored 
      This patch adds helper bpf_perf_prog_read_cvalue for perf event based bpf
programs, to read event counter and enabled/running time.
The enabled/running time is accumulated since the perf event open.

The typical use case for perf event based bpf program is to attach itself
to a single event. In such cases, if it is desirable to get scaling factor
between two bpf invocations, users can can save the time values in a map,
and use the value from the map and the current value to calculate
the scaling factor.
Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Acked-by: default avatarAlexei Starovoitov <ast@fb.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4bebdc7a
    • Yonghong Song's avatar
      bpf: add a test case for helper bpf_perf_event_read_value · 020a32d9
      Yonghong Song authored 
      The bpf sample program tracex6 is enhanced to use the new
helper to read enabled/running time as well.
Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Acked-by: default avatarAlexei Starovoitov <ast@fb.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      020a32d9
    • Yonghong Song's avatar
      bpf: add helper bpf_perf_event_read_value for perf event array map · 908432ca
      Yonghong Song authored 
      Hardware pmu counters are limited resources. When there are more
pmu based perf events opened than available counters, kernel will
multiplex these events so each event gets certain percentage
(but not 100%) of the pmu time. In case that multiplexing happens,
the number of samples or counter value will not reflect the
case compared to no multiplexing. This makes comparison between
different runs difficult.

Typically, the number of samples or counter value should be
normalized before comparing to other experiments. The typical
normalization is done like:
  normalized_num_samples = num_samples * time_enabled / time_running
  normalized_counter_value = counter_value * time_enabled / time_running
where time_enabled is the time enabled for event and time_running is
the time running for event since last normalization.

This patch adds helper bpf_perf_event_read_value for kprobed based perf
event array map, to read perf counter and enabled/running time.
The enabled/running time is accumulated since the perf event open.
To achieve scaling factor between two bpf invocations, users
can can use cpu_id as the key (which is typical for perf array usage model)
to remember the previous value and do the calculation inside the
bpf program.
Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Acked-by: default avatarAlexei Starovoitov <ast@fb.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      908432ca
    • Yonghong Song's avatar
      bpf: perf event change needed for subsequent bpf helpers · 97562633
      Yonghong Song authored 
      This patch does not impact existing functionalities.
It contains the changes in perf event area needed for
subsequent bpf_perf_event_read_value and
bpf_perf_prog_read_value helpers.
Signed-off-by: default avatarYonghong Song <yhs@fb.com>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      97562633
    • Amine Kherbouche's avatar
      ip_tunnel: add mpls over gre support · bdc47641
      Amine Kherbouche authored 
      This commit introduces the MPLSoGRE support (RFC 4023), using ip tunnel
API by simply adding ipgre_tunnel_encap_(add|del)_mpls_ops() and the new
tunnel type TUNNEL_ENCAP_MPLS.
Signed-off-by: default avatarAmine Kherbouche <amine.kherbouche@6wind.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bdc47641
    • David S. Miller's avatar
      Merge branch 'fib6-rcu' · 2af48d43
      David S. Miller authored 
      Wei Wang says:

====================
ipv6: replace rwlock with rcu and spinlock in fib6 table

Currently, fib6 table is protected by rwlock. During route lookup,
reader lock is taken and during route insertion, deletion or
modification, writer lock is taken. This is a very inefficient
implementation because the fastpath always has to do the operation
to grab the reader lock.
According to my latest syn flood test on an iota ivybridage machine
with 2 10G mlx nics bonded together, each with 8 rx queues on 2 NUMA
nodes, and with the upstream net-next kernel:
ipv4 stack can handle around 4.2Mpps
ipv6 stack can handle around 1.3Mpps

In order to close the gap of the performance number between ipv4
and ipv6 stack, this patch series tries to get rid of the usage of
the rwlock and replace it with rcu and spinlock protection. This will
greatly speed up the fastpath performance as it only needs to hold
rcu which is much less expensive than grabbing the reader lock. It
also makes ipv6 fib implementation more consistent with ipv4.

In order to be able to replace the current rwlock with rcu and
spinlock, some preparation work is needed:
Patch 1-8 introduces a per-route hash table (protected by rcu and a
different spinlock) to store all cached routes created by pmtu and ip
redirect under its main route. This makes the main fib6 tree only
contain static routes.
Patch 9-14 prepares all the reader path to be ready to tolerate
concurrent writer.
Patch 15 finally does the rwlock to rcu and spinlock conversion.
Patch 16 takes care of rt6_stats.

After this patch series, in the same syn flood test,
ipv6 stack can now handle around 3.5Mpps compared to previous 1.3Mpps
in my test setup.

After this patch series, there are still some improvements that should
be done in ipv6 stack:
1. During route lookup, dst_use() is called everytime on the selected
route to update dst->__use and dst->lastuse. This dirties the cacheline
and causes extra cacheline miss and should be avoided.
2. when no route is found in the current table, net->ip6.ipv6_null_entry
is used and refcnt is taken on it. As there is no pcpu cache for this
specific route, frequent change on the refcnt for this route causes
quite some cacheline misses.
And to make things worse, if CONFIG_IPV6_MULTIPLE_TABLES is defined,
output path route lookup always starts with local table first and
guarantees to hit net->ipv6.ip6_null_entry before continuing to do
lookup in the main table.
These operations on net->ipv6.ip6_null_entry could potentially be
avoided.
3. ipv6 input path route lookup grabs refcnt on dst. This is different
from ipv4. We could potentially change this behavior to let ipv6 input
path route lookup not to grab refcnt on dst. However, it does not give
us much performance boost as we currently have pcpu route cache for
input path as well in ipv6. But this work probably is still worth doing
to unify ipv6 and ipv4 route lookup behavior.

The above issues will be addressed separately after this patch series
has been accepted.

This is a joint work with Martin KaFai Lau and Eric Dumazet. And many
many thanks to them for their inspiring ideas and big big code review
efforts.
====================
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2af48d43
    • Wei Wang's avatar
      ipv6: take care of rt6_stats · 81eb8447
      Wei Wang authored 
      Currently, most of the rt6_stats are not hooked up correctly. As the
last part of this patch series, hook up all existing rt6_stats and add
one new stat fib_rt_uncache to indicate the number of routes in the
uncached list.
For details of the stats, please refer to the comments added in
include/net/ip6_fib.h.

Note: fib_rt_alloc and fib_rt_uncache are not guaranteed to be modified
under a lock. So atomic_t is used for them.
Signed-off-by: default avatarWei Wang <weiwan@google.com>
Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      81eb8447
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7