Examples directory has been growing, so add a bit of organization.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Bump ulimit for locked memory in test wrapper

This follows from a change in upstream kernel for counting bpf maps
against the locked memory limit.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Python: fix detach_kprobe()

As open_kprobes contains not fd but pointer to struct perf_reader,
it should call lib.perf_reader_free() instead of os.close()

perf_reader: allow more than one reader to poll

When more than one events are used with attach_kprobe, the
perf_reader_poll() will segfault by buffer overflow like below.

*** buffer overflow detected ***: python terminated
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x7338f)[0x7fcc971fb38f]
/lib/x86_64-linux-gnu/libc.so.6(__fortify_fail+0x5c)[0x7fcc97292c9c]
/lib/x86_64-linux-gnu/libc.so.6(+0x109b60)[0x7fcc97291b60]
/lib/x86_64-linux-gnu/libc.so.6(+0x10ac04)[0x7fcc97292c04]
/usr/lib/x86_64-linux-gnu/libbcc.so(perf_reader_poll+0x42)[0x7fcc93969cc2]
/usr/lib/x86_64-linux-gnu/libffi.so.6(ffi_call_unix64+0x4c)[0x7fcc95c2badc]
/usr/lib/x86_64-linux-gnu/libffi.so.6(ffi_call+0x1fc)[0x7fcc95c2b40c]
/usr/lib/python2.7/lib-dynload/_ctypes.x86_64-linux-gnu.so(_ctypes_callproc+0x48e)[0x7fcc95e425fe]
/usr/lib/python2.7/lib-dynload/_ctypes.x86_64-linux-gnu.so(+0x15f9e)[0x7fcc95e43f9e]
python(PyEval_EvalFrameEx+0x965)[0x499be5]
python(PyEval_EvalCodeEx+0x2ac)[0x4a090c]
python(PyEval_EvalFrameEx+0x7d2)[0x499a52]
python[0x4a1634]
python(PyRun_FileExFlags+0x92)[0x44e4a5]
python(PyRun_SimpleFileExFlags+0x2ee)[0x44ec9f]
python(Py_Main+0xb5e)[0x44f904]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5)[0x7fcc971a9ec5]
python[0x578c4e]

softirq and hardirq

tcpconnect for IPv4 and IPv6, and make tcpv4connect a trimmed example

perf_reader : add timeout argument to perf_reader_poll

tcpaccept

Fixes for deb/rpm packaging

These fixes are manually included in the released 0.1.7 packages, but
will help with future builds.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Update tag to v0.1.7

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

handle return value in kretprobe handler for tcpv4connect

Fix an uninitialized variable access in test_clang

Signed-off-by: Yonghong Song <yhs@plumgrid.com>

Signed-off-by: Yonghong Song <yhs@plumgrid.com>

Make KeyboardInterrupt catch more aggressive

Fixes: #186
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Fixes for table indexing and clear()

In the case that python process tries to clear() a table object while
the bpf program is still running and doing lookup_or_init, the python
clean() routine will race with the bpf program (and bpf will win in the
case of frequent kprobe hits) causing a hang. Instead, first get the
full list of keys and then delete them rather than rely on the default
popitem implementation.

Fixes: #233
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

In the case that 0-filled keys are valid in the table, the previous
algorithm did not properly iterate.

The API of the bpf_get_next_key routine is such that the iteration
over a map should start with an invalid key. When a 0 key is valid, this
causes iteration to start anywhere inside the hash table, skipping some
entries. So, add logic to the Iter object to test if the init key is
invalid. If otherwise, try a few alternatives until an invalid key is
found. If none found, raise an exception.

Also adds a test for indexing arrays from 0, which nows works with this
too.

Fixes: #260
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Don't treat fundamentally typed args as needing probe_read

The rewriter was aggressively parsing PoD types as requiring probe_read
and poisoning other decls when those arguments were used.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Mask function calls from influencing probe_read

Calls to functions were propagating the needs_probe state, causing map
values to require a probe_read improperly. Although there may be a use
case for this, generally it will not be needed and should be solved
differently.

Fixes: #256
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Add ability to consume perf events in python

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

This adds the ability to consume perf events in libbpf/python using the
ring buffer. For now, this is the only way to get access to the function
call graph. Only kernel functions are supported.

It does this by introducing a new set of libbpf helper functions that
can open the perf fd, mmap it, and poll over the events as they are
submitted by the kernel. This allow for faster event processing than
trace_printks, but has not been tested.

The functionality is disabled by default, the user can enable it by
passing a non-empty cb parameter into the BPF constructor. That cb
function will be invoked for each event that is read from the buffer.
Buffers are per-fd, so each event is distinct as well as separated from
other processes that may be running simultaneously.

The initial test case uses this functionality to build a histogram of
events keyed by the callchain.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

tcpv4connect