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  1. 27 Jun, 2019 14 commits
  3. 26 Jun, 2019 5 commits
  5. 25 Jun, 2019 6 commits
  7. 23 Jun, 2019 11 commits
    • David S. Miller's avatar
      Merge branch 'ipv6-avoid-taking-refcnt-on-dst-during-route-lookup' · 7d30a7f6
      David S. Miller authored 
      Wei Wang says:

====================
ipv6: avoid taking refcnt on dst during route lookup

Ipv6 route lookup code always grabs refcnt on the dst for the caller.
But for certain cases, grabbing refcnt is not always necessary if the
call path is rcu protected and the caller does not cache the dst.
Another issue in the route lookup logic is:
When there are multiple custom rules, we have to do the lookup into
each table associated to each rule individually. And when we can't
find the route in one table, we grab and release refcnt on
net->ipv6.ip6_null_entry before going to the next table.
This operation is completely redundant, and causes false issue because
net->ipv6.ip6_null_entry is a shared object.

This patch set introduces a new flag RT6_LOOKUP_F_DST_NOREF for route
lookup callers to set, to avoid any manipulation on the dst refcnt. And
it converts the major input and output path to use it.

The performance gain is noticable.
I ran synflood tests between 2 hosts under the same switch. Both hosts
have 20G mlx NIC, and 8 tx/rx queues.
Sender sends pure SYN flood with random src IPs and ports using trafgen.
Receiver has a simple TCP listener on the target port.
Both hosts have multiple custom rules:
- For incoming packets, only local table is traversed.
- For outgoing packets, 3 tables are traversed to find the route.
The packet processing rate on the receiver is as follows:
- Before the fix: 3.78Mpps
- After the fix:  5.50Mpps

v2->v3:
- Handled fib6_rule_lookup() when CONFIG_IPV6_MULTIPLE_TABLES is not
  configured in patch 03 (suggested by David Ahern)
- Removed the renaming of l3mdev_link_scope_lookup() in patch 05
  (suggested by David Ahern)
- Moved definition of ip6_route_output_flags() from an inline function
  in /net/ipv6/route.c to net/ipv6/route.c in order to address kbuild
  error in patch 05

v1->v2:
- Added a helper ip6_rt_put_flags() in patch 3 suggested by David Miller
====================
Reviewed-by: default avatarDavid Ahern <dsahern@gmail.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7d30a7f6
    • Wei Wang's avatar
      ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF · 7d9e5f42
      Wei Wang authored 
      For tx path, in most cases, we still have to take refcnt on the dst
cause the caller is caching the dst somewhere. But it still is
beneficial to make use of RT6_LOOKUP_F_DST_NOREF flag while doing the
route lookup. It is cause this flag prevents manipulating refcnt on
net->ipv6.ip6_null_entry when doing fib6_rule_lookup() to traverse each
routing table. The null_entry is a shared object and constant updates on
it cause false sharing.

We converted the current major lookup function ip6_route_output_flags()
to make use of RT6_LOOKUP_F_DST_NOREF.

Together with the change in the rx path, we see noticable performance
boost:
I ran synflood tests between 2 hosts under the same switch. Both hosts
have 20G mlx NIC, and 8 tx/rx queues.
Sender sends pure SYN flood with random src IPs and ports using trafgen.
Receiver has a simple TCP listener on the target port.
Both hosts have multiple custom rules:
- For incoming packets, only local table is traversed.
- For outgoing packets, 3 tables are traversed to find the route.
The packet processing rate on the receiver is as follows:
- Before the fix: 3.78Mpps
- After the fix:  5.50Mpps
Signed-off-by: default avatarWei Wang <weiwan@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7d9e5f42
    • Wei Wang's avatar
      ipv6: convert rx data path to not take refcnt on dst · 67f415dd
      Wei Wang authored 
      ip6_route_input() is the key function to do the route lookup in the
rx data path. All the callers to this function are already holding rcu
lock. So it is fairly easy to convert it to not take refcnt on the dst:
We pass in flag RT6_LOOKUP_F_DST_NOREF and do skb_dst_set_noref().
This saves a few atomic inc or dec operations and should boost
performance overall.
This also makes the logic more aligned with v4.
Signed-off-by: default avatarWei Wang <weiwan@google.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarMahesh Bandewar <maheshb@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      67f415dd
    • Wei Wang's avatar
      ipv6: honor RT6_LOOKUP_F_DST_NOREF in rule lookup logic · d64a1f57
      Wei Wang authored 
      This patch specifically converts the rule lookup logic to honor this
flag and not release refcnt when traversing each rule and calling
lookup() on each routing table.
Similar to previous patch, we also need some special handling of dst
entries in uncached list because there is always 1 refcnt taken for them
even if RT6_LOOKUP_F_DST_NOREF flag is set.
Signed-off-by: default avatarWei Wang <weiwan@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d64a1f57
    • Wei Wang's avatar
      ipv6: initialize rt6->rt6i_uncached in all pre-allocated dst entries · 74109218
      Wei Wang authored 
      Initialize rt6->rt6i_uncached on the following pre-allocated dsts:
net->ipv6.ip6_null_entry
net->ipv6.ip6_prohibit_entry
net->ipv6.ip6_blk_hole_entry

This is a preparation patch for later commits to be able to distinguish
dst entries in uncached list by doing:
!list_empty(rt6->rt6i_uncached)
Signed-off-by: default avatarWei Wang <weiwan@google.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarMahesh Bandewar <maheshb@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      74109218
    • Wei Wang's avatar
      ipv6: introduce RT6_LOOKUP_F_DST_NOREF flag in ip6_pol_route() · 0e09edcc
      Wei Wang authored 
      This new flag is to instruct the route lookup function to not take
refcnt on the dst entry. The user which does route lookup with this flag
must properly use rcu protection.
ip6_pol_route() is the major route lookup function for both tx and rx
path.
In this function:
Do not take refcnt on dst if RT6_LOOKUP_F_DST_NOREF flag is set, and
directly return the route entry. The caller should be holding rcu lock
when using this flag, and decide whether to take refcnt or not.

One note on the dst cache in the uncached_list:
As uncached_list does not consume refcnt, one refcnt is always returned
back to the caller even if RT6_LOOKUP_F_DST_NOREF flag is set.
Uncached dst is only possible in the output path. So in such call path,
caller MUST check if the dst is in the uncached_list before assuming
that there is no refcnt taken on the returned dst.
Signed-off-by: default avatarWei Wang <weiwan@google.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarMahesh Bandewar <maheshb@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0e09edcc
    • Russell King's avatar
      doc: phy: document some PHY_INTERFACE_MODE_xxx settings · 8c25c0cb
      Russell King authored 
      There seems to be some confusion surrounding three PHY interface modes,
specifically 1000BASE-X, 2500BASE-X and SGMII.  Add some documentation
to phylib detailing precisely what these interface modes refer to.
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8c25c0cb
    • Qian Cai's avatar
      inet: fix compilation warnings in fqdir_pre_exit() · 08003d0b
      Qian Cai authored 
      The linux-next commit "inet: fix various use-after-free in defrags
units" [1] introduced compilation warnings,

./include/net/inet_frag.h:117:1: warning: 'inline' is not at beginning
of declaration [-Wold-style-declaration]
 static void inline fqdir_pre_exit(struct fqdir *fqdir)
 ^~~~~~
In file included from ./include/net/netns/ipv4.h:10,
                 from ./include/net/net_namespace.h:20,
                 from ./include/linux/netdevice.h:38,
                 from ./include/linux/icmpv6.h:13,
                 from ./include/linux/ipv6.h:86,
                 from ./include/net/ipv6.h:12,
                 from ./include/rdma/ib_verbs.h:51,
                 from ./include/linux/mlx5/device.h:37,
                 from ./include/linux/mlx5/driver.h:51,
                 from
drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:37:

[1] https://lore.kernel.org/netdev/20190618180900.88939-3-edumazet@google.com/Signed-off-by: default avatarQian Cai <cai@lca.pw>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      08003d0b
    • Rasmus Villemoes's avatar
      net: dsa: mv88e6xxx: introduce helpers for handling chip->reg_lock · c9acece0
      Rasmus Villemoes authored 
      This is a no-op that simply moves all locking and unlocking of
->reg_lock into trivial helpers. I did that to be able to easily add
some ad hoc instrumentation to those helpers to get some information
on contention and hold times of the mutex. Perhaps others want to do
something similar at some point, so this frees them from doing the
'sed -i' yoga, and have a much smaller 'git diff' while fiddling.
Signed-off-by: default avatarRasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: default avatarVivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c9acece0
    • Sameeh Jubran's avatar
      net: ena: Fix bug where ring allocation backoff stopped too late · 3e5bfb18
      Sameeh Jubran authored 
      The current code of create_queues_with_size_backoff() allows the ring size
to become as small as ENA_MIN_RING_SIZE/2. This is a bug since we don't
want the queue ring to be smaller than ENA_MIN_RING_SIZE

In this commit we change the loop's termination condition to look at the
queue size of the next iteration instead of that of the current one,
so that the minimal queue size again becomes ENA_MIN_RING_SIZE.

Fixes: eece4d2a ("net: ena: add ethtool function for changing io queue sizes")
Signed-off-by: default avatarArthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: default avatarSameeh Jubran <sameehj@amazon.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3e5bfb18
    • Colin Ian King's avatar
      hinic: fix dereference of pointer hwdev before it is null checked · 137e4e1a
      Colin Ian King authored 
      Currently pointer hwdev is dereferenced when assigning hwif before
hwdev is null checked.  Fix this by only derefencing hwdev after the
null check.

Addresses-Coverity: ("Dereference before null check")
Fixes: 4fdc51bb ("hinic: add support for rss parameters with ethtool")
Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      137e4e1a
  9. 22 Jun, 2019 4 commits
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