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  1. 24 Jan, 2017 33 commits
  3. 23 Jan, 2017 7 commits
    • David S. Miller's avatar
      Merge branch 'bpf-lpm' · 2acc76cb
      David S. Miller authored 
      Daniel Mack says:

====================
bpf: add longest prefix match map

This patch set adds a longest prefix match algorithm that can be used
to match IP addresses to a stored set of ranges. It is exposed as a
bpf map type.

Internally, data is stored in an unbalanced tree of nodes that has a
maximum height of n, where n is the prefixlen the trie was created
with.

Note that this has nothing to do with fib or fib6 and is in no way meant
to replace or share code with it. It's rather a much simpler
implementation that is specifically written with bpf maps in mind.

Patch 1/2 adds the implementation, 2/2 an extensive test suite and 3/3
has benchmarking code for the new trie type.

Feedback is much appreciated.

Changelog:

v3 -> v4:
	* David added a 3rd patch that augments map_perf_test for
	  LPM trie benchmarks
	* Limit allocation of maps of this new type to CAP_SYS_ADMIN
	  for now, as requested by Alexei
	* Add a stub .map_delete_elem so the core does not stumble
	  over a NULL pointer when the syscall is invoked
	* Tests for non-power-of-2 prefix lengths were added
	* More comment style fixes

v2 -> v3:
	* Store both the key match data and the caller provided
	  value in the same byte array attached to a node. This
	  avoids double allocations
	* Bring back node->flags to distinguish between 'real'
	  and intermediate nodes
	* Fix comment style and some typos

v1 -> v2:
	* Turn spin lock into raw spinlock
	* Lock with irqsave options during trie_update_elem()
	* Return -ENOMEM properly from trie_alloc()
	* Force attr->flags == BPF_F_NO_PREALLOC during creation
	* Set trie->map.pages after creation to account for map memory
	* Allow arbitrary value sizes
	* Removed node->flags and denode intermediate nodes through
	  node->value == NULL instead

rfc -> v1:
	* Add __rcu pointer annotations to make sparse happy
	* Fold _lpm_trie_find_target_node() into its only caller
	* Fix some minor documentation issues
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2acc76cb
    • David Herrmann's avatar
      samples/bpf: add lpm-trie benchmark · b8a943e2
      David Herrmann authored 
      Extend the map_perf_test_{user,kern}.c infrastructure to stress test
lpm-trie lookups. We hook into the kprobe on sys_gettid() and measure
the latency depending on trie size and lookup count.

On my Intel Haswell i7-6400U, a single gettid() syscall with an empty
bpf program takes roughly 6.5us on my system. Lookups in empty tries
take ~1.8us on first try, ~0.9us on retries. Lookups in tries with 8192
entries take ~7.1us (on the first _and_ any subsequent try).
Signed-off-by: default avatarDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: default avatarDaniel Mack <daniel@zonque.org>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b8a943e2
    • David Herrmann's avatar
      bpf: Add tests for the lpm trie map · 4d3381f5
      David Herrmann authored 
      The first part of this program runs randomized tests against the
lpm-bpf-map. It implements a "Trivial Longest Prefix Match" (tlpm)
based on simple, linear, single linked lists. The implementation
should be pretty straightforward.

Based on tlpm, this inserts randomized data into bpf-lpm-maps and
verifies the trie-based bpf-map implementation behaves the same way
as tlpm.

The second part uses 'real world' IPv4 and IPv6 addresses and tests
the trie with those.
Signed-off-by: default avatarDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: default avatarDaniel Mack <daniel@zonque.org>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4d3381f5
    • Daniel Mack's avatar
      bpf: add a longest prefix match trie map implementation · b95a5c4d
      Daniel Mack authored 
      This trie implements a longest prefix match algorithm that can be used
to match IP addresses to a stored set of ranges.

Internally, data is stored in an unbalanced trie of nodes that has a
maximum height of n, where n is the prefixlen the trie was created
with.

Tries may be created with prefix lengths that are multiples of 8, in
the range from 8 to 2048. The key used for lookup and update operations
is a struct bpf_lpm_trie_key, and the value is a uint64_t.

The code carries more information about the internal implementation.
Signed-off-by: default avatarDaniel Mack <daniel@zonque.org>
Reviewed-by: default avatarDavid Herrmann <dh.herrmann@gmail.com>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b95a5c4d
    • Bhumika Goyal's avatar
      net: xilinx: constify net_device_ops structure · 10eeb5e6
      Bhumika Goyal authored 
      Declare net_device_ops structure as const as it is only stored in
the netdev_ops field of a net_device structure. This field is of type
const, so net_device_ops structures having same properties can be made
const too.
Done using Coccinelle:

@r1 disable optional_qualifier@
identifier i;
position p;
@@
static struct net_device_ops i@p={...};

@ok1@
identifier r1.i;
position p;
struct net_device ndev;
@@
ndev.netdev_ops=&i@p

@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct net_device_ops i;

File size before:
   text	   data	    bss	    dec	    hex	filename
   6201	    744	      0	   6945	   1b21 ethernet/xilinx/xilinx_emaclite.o

File size after:
   text	   data	    bss	    dec	    hex	filename
   6745	    192	      0	   6937	   1b19 ethernet/xilinx/xilinx_emaclite.o
Signed-off-by: default avatarBhumika Goyal <bhumirks@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      10eeb5e6
    • Bhumika Goyal's avatar
      net: moxa: constify net_device_ops structures · 30bd2f52
      Bhumika Goyal authored 
      Declare net_device_ops structure as const as it is only stored in
the netdev_ops field of a net_device structure. This field is of type
const, so net_device_ops structures having same properties can be made
const too.
Done using Coccinelle:

@r1 disable optional_qualifier@
identifier i;
position p;
@@
static struct net_device_ops i@p={...};

@ok1@
identifier r1.i;
position p;
struct net_device ndev;
@@
ndev.netdev_ops=&i@p

@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct net_device_ops i;

File size before:
   text	   data	    bss	    dec	    hex	filename
   4821	    744	      0	   5565	   15bd ethernet/moxa/moxart_ether.o

File size after:
   text	   data	    bss	    dec	    hex	filename
   5373	    192	      0	   5565	   15bd ethernet/moxa/moxart_ether.o
Signed-off-by: default avatarBhumika Goyal <bhumirks@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      30bd2f52
    • Timur Tabi's avatar
      net: qcom/emac: claim the irq only when the device is opened · 4404323c
      Timur Tabi authored 
      During reset, functions emac_mac_down() and emac_mac_up() are called,
so we don't want to free and claim the IRQ unnecessarily.  Move those
operations to open/close.
Signed-off-by: default avatarTimur Tabi <timur@codeaurora.org>
Reviewed-by: default avatarLino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4404323c
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