kernel_optimize_test/tools
Arnaldo Carvalho de Melo 822c2621da perf bpf: Include uapi/linux/bpf.h from the 'perf trace' script's bpf.h
The next example scripts need the definition for the BPF functions, i.e.
things like BPF_FUNC_probe_read, and in time will require lots of other
definitions found in uapi/linux/bpf.h, so include it from the bpf.h file
included from the eBPF scripts build with clang via '-e bpf_script.c'
like in this example:

  $ tail -8 tools/perf/examples/bpf/5sec.c
  #include <bpf.h>

  int probe(hrtimer_nanosleep, rqtp->tv_sec)(void *ctx, int err, long sec)
  {
	return sec == 5;
  }

  license(GPL);
  $

That 'bpf.h' include in the 5sec.c eBPF example will come from a set of
header files crafted for building eBPF objects, that in a end-user
system will come from:

  /usr/lib/perf/include/bpf/bpf.h

And will include <uapi/linux/bpf.h> either from the place where the
kernel was built, or from a kernel-devel rpm package like:

  -working-directory /lib/modules/4.17.9-100.fc27.x86_64/build

That is set up by tools/perf/util/llvm-utils.c, and can be overriden
by setting the 'kbuild-dir' variable in the "llvm" ~/.perfconfig file,
like:

  # cat ~/.perfconfig
  [llvm]
       kbuild-dir = /home/foo/git/build/linux

This usually doesn't need any change, just documenting here my findings
while working with this code.

In the future we may want to instead just use what is in
/usr/include/linux/bpf.h, that comes from the UAPI provided from the
kernel sources, for now, to avoid getting the kernel's non-UAPI
"linux/bpf.h" file, that will cause clang to fail and is not what we
want anyway (no BPF function definitions, etc), do it explicitely by
asking for "uapi/linux/bpf.h".

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zd8zeyhr2sappevojdem9xxt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-01 12:34:06 -03:00
..
accounting
arch Merge remote-tracking branch 'tip/perf/urgent' into perf/core 2018-07-31 09:55:45 -03:00
bpf tools/bpftool: Fix segfault case regarding 'pin' arguments 2018-07-20 10:16:54 +02:00
build tools: build: Use HOSTLDFLAGS with fixdep 2018-07-13 00:48:18 +09:00
cgroup
firewire
gpio
hv
iio
include tools include uapi: Grab a copy of linux/in.h 2018-07-31 10:52:37 -03:00
kvm/kvm_stat
laptop
leds
lib docs: Fix some broken references 2018-06-15 18:10:01 -03:00
memory-model
nfsd
objtool objtool: Use '.strtab' if '.shstrtab' doesn't exist, to support ORC tables on Clang 2018-07-14 14:59:42 +02:00
pci
pcmcia
perf perf bpf: Include uapi/linux/bpf.h from the 'perf trace' script's bpf.h 2018-08-01 12:34:06 -03:00
power Merge branch 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2018-06-21 00:37:04 +02:00
scripts
spi
testing Various fixes to the tracing infrastructure: 2018-07-27 09:50:33 -07:00
thermal/tmon
time
usb tools: usb: ffs-test: Fix build on big endian systems 2018-07-17 10:12:51 +03:00
virtio sg: remove ->sg_magic member 2018-06-29 08:48:06 -06:00
vm mm: mark pages in use for page tables 2018-06-07 17:34:37 -07:00
wmi
Makefile