GitLab

bpf_probe_read()'s third argument is no longer rewritten. Instead, use a
temporary variable (like #1973) to avoid a memory access error.

Before:

```
$ sudo biolatency -D 1
bpf: Failed to load program: Permission denied
0: (79) r1 = *(u64 *)(r1 +112)
1: (7b) *(u64 *)(r10 -8) = r1
[..]
R1 invalid mem access 'inv'

HINT: The invalid mem access 'inv' error can happen if you try to
dereference memory without first using bpf_probe_read() to copy it to
the BPF stack. Sometimes the bpf_probe_read is automatic by the bcc
rewriter, other times you'll need to be explicit.
```

After, works as expected.

Use of this argparse constructor keyword is causing regression
test failures, and its use was nice-to-have - this means the -e
shorthand for --ebpf will be available iff its not been used in
another add_argument call.  Neither -e/--ebpf are advertised in
the usage message anyway.

As discussed in https://github.com/iovisor/bcc/pull/1531


review comments.
Signed-off-by: Nathan Scott <nathans@redhat.com>

Several python tools allow their eBPF code to be printed to
stdout for debugging.  There are other projects that would
like to share these program definitions however, instead of
duplicating code.  Formalise an -e/--ebpf option, and start
using it in several tools (more to come).
Signed-off-by: Nathan Scott <nathans@redhat.com>

In order not to miss some files in the tools and examples source
directories, use cmake file(GLOB) to collect relevant files. To ease the
implementation, move all tools to be .py suffixed in the source, but
sans-suffix in the installation (same as before)

In addition, to prevent future API breakage confusion (though of course
that may still happen), use CDLL("libbcc.so.0") in the bcc __init__.py.

Fixes: #317
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

Signed-off-by: Alexei Starovoitov <ast@fb.com>

This adds support for a specialized histogram type, which underneath
maps to an array or a hash table, depending on key type. With no
arguments, it takes on the type `u64 table[64];`. The other current
supported key type is `struct { int32|int64 bucket; int32|int64 slot }`.

To print these automatically, print_log2_hist is underneath split into
two types of printouts, one which prints the single histogram, and
another which prints a histogram for each unique `bucket` value.

See test_histogram.py for examples.

Fixes: #144
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>