sync bpf compat headers with latest net-next

add an example of accessing an externally created map in C++

Some application may need to access a pinned map which is not
created by bcc. This example shows how to incorporate such
maps with C++ APIs.

Basically, the application needs to create a TableStorage and
pre-populate it with pinned map before calling BPF constructor.
The bpf program defines this pinned map as an "extern" map.
Signed-off-by: Yonghong Song <yhs@fb.com>

add the tcpstates tool

docs: add latest eBPF helpers to features list

This patch extends the PYTHON_CMD cmake variable to allow a list of
Python binaries and installs the bcc Python bindings for each Python
installation. The Debian control files are updated to generate bindings
for Python 2 and Python 3. Compiled Python files are excluded from the
Debian packages.
Signed-off-by: Andreas Gerstmayr <andreas@gerstmayr.me>

Add move constructor for BPFStackTable

tcplife: switch to the new sock:inet_sock_set_state tracepoint

properly retrieve IP address from array for python2.7

for python2.7 IP address(src_ip,dst_ip) conversion doesn't work
as expected and throws

Traceback (most recent call last):
  File "_ctypes/callbacks.c", line 315, in 'calling callback function'
  File "/usr/local/lib/python2.7/site-packages/bcc/table.py", line 526, in raw_cb_
    callback(cpu, data, size)
  File "./examples/networking/tc_perf_event.py", line 60, in print_skb_event
    (cpu, socket.inet_ntop(socket.AF_INET6, src_ip),
ValueError: invalid length of packed IP address string

IP string looks like
[254, 128, 0, 0, 0, 0, 0, 0, 156, 237, 12, 255, 254, 42, 90, 31]
Signed-off-by: Nirmoy Das <ndas@suse.de>

cmake: search for iperf3 if there is no iperf

Some destro just provide iperf3 like openSUSE Tumbleweed
Signed-off-by: Nirmoy Das <ndas@suse.de>

tools/slabratetop: detect the current memory allocator

fix fd leakage

Currently, slabratetop always included slub_def.h. For the system uses
SLAB, the definition of 'struct kmem_cache' is different and the eBPF
program would fetch the wrong field and print garbages.
Signed-off-by: Gary Lin <glin@suse.com>

bpf_prog_compute_tag() isn't closing socket fds
before successful return
Signed-off-by: Nirmoy Das <ndas@suse.de>

Perf Event interface with raw perf_event_attr argument

docs: fix commit hash and link for bpf_redirect_map()

The link wrongly pointed to the same commit as for
bpf_sk_redirect_map().

Links to recent articles on LWN.net

fix CMakefile for lua

Issue #1621 reported an issue where bcc-lua has an unresolved
symbol bcc_resolve_symname. This is a side effect of previous
cmake file refactorization which permits better control
over what features can be enabled during build time.
The refactorization caused some symbols in bcc_syms.cc
got lost in the final link which produced bcc-lua.

This patch fixed the issue by add a new static library target
bcc-lua-static and adds bcc_syms.cc to it when the library
is created and hence preserved the symbol.

Also removed unnecessary linking for clang_frontend library.
Signed-off-by: Yonghong Song <yhs@fb.com>

C++ API: Allow obtaining BPFPerfBuffer pointer for polling

Tool tcpsubnet

Fix BPFModule allocation / de-allocation mismatch