Perf BPF filter test fails in environment where "clang" is not
installed.
Test failure logs:
<<>>
42: BPF filter :
42.1: Basic BPF filtering : Skip
42.2: BPF pinning : FAILED!
42.3: BPF prologue generation : FAILED!
<<>>
Enabling verbose option provided debug logs which says clang/llvm needs
to be installed. Snippet of verbose logs:
<<>>
42.2: BPF pinning :
--- start ---
test child forked, pid 61423
ERROR: unable to find clang.
Hint: Try to install latest clang/llvm to support BPF.
Check your $PATH
<<logs_here>>
Failed to compile test case: 'Basic BPF llvm compile'
Unable to get BPF object, fix kbuild first
test child finished with -1
---- end ----
BPF filter subtest 2: FAILED!
<<>>
Here subtests, "BPF pinning" and "BPF prologue generation" failed and
logs shows clang/llvm is needed. After installing clang, testcase
passes.
Reason on why subtest failure happens though logs has proper debug
information:
Main function __test__bpf calls test_llvm__fetch_bpf_obj by
passing 4th argument as true ( 4th arguments maps to parameter
"force" in test_llvm__fetch_bpf_obj ). But this will cause
test_llvm__fetch_bpf_obj to skip the check for clang/llvm.
Snippet of code part which checks for clang based on
parameter "force" in test_llvm__fetch_bpf_obj:
<<>>
if (!force && (!llvm_param.user_set_param &&
<<>>
Since force is set to "false", test won't get skipped and fails to
compile test case. The BPF code compilation needs clang, So pass the
fourth argument as "false" and also skip the test if reason for return
is "TEST_SKIP"
After the patch:
<<>>
42: BPF filter :
42.1: Basic BPF filtering : Skip
42.2: BPF pinning : Skip
42.3: BPF prologue generation : Skip
<<>>
Fixes: ba1fae431e ("perf test: Add 'perf test BPF'")
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nageswara R Sastry <rnsastry@linux.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lore.kernel.org/r/20220511115438.84032-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Andrii Nakryiko says:
====================
bpf-next 2021-12-10 v2
We've added 115 non-merge commits during the last 26 day(s) which contain
a total of 182 files changed, 5747 insertions(+), 2564 deletions(-).
The main changes are:
1) Various samples fixes, from Alexander Lobakin.
2) BPF CO-RE support in kernel and light skeleton, from Alexei Starovoitov.
3) A batch of new unified APIs for libbpf, logging improvements, version
querying, etc. Also a batch of old deprecations for old APIs and various
bug fixes, in preparation for libbpf 1.0, from Andrii Nakryiko.
4) BPF documentation reorganization and improvements, from Christoph Hellwig
and Dave Tucker.
5) Support for declarative initialization of BPF_MAP_TYPE_PROG_ARRAY in
libbpf, from Hengqi Chen.
6) Verifier log fixes, from Hou Tao.
7) Runtime-bounded loops support with bpf_loop() helper, from Joanne Koong.
8) Extend branch record capturing to all platforms that support it,
from Kajol Jain.
9) Light skeleton codegen improvements, from Kumar Kartikeya Dwivedi.
10) bpftool doc-generating script improvements, from Quentin Monnet.
11) Two libbpf v0.6 bug fixes, from Shuyi Cheng and Vincent Minet.
12) Deprecation warning fix for perf/bpf_counter, from Song Liu.
13) MAX_TAIL_CALL_CNT unification and MIPS build fix for libbpf,
from Tiezhu Yang.
14) BTF_KING_TYPE_TAG follow-up fixes, from Yonghong Song.
15) Selftests fixes and improvements, from Ilya Leoshkevich, Jean-Philippe
Brucker, Jiri Olsa, Maxim Mikityanskiy, Tirthendu Sarkar, Yucong Sun,
and others.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (115 commits)
libbpf: Add "bool skipped" to struct bpf_map
libbpf: Fix typo in btf__dedup@LIBBPF_0.0.2 definition
bpftool: Switch bpf_object__load_xattr() to bpf_object__load()
selftests/bpf: Remove the only use of deprecated bpf_object__load_xattr()
selftests/bpf: Add test for libbpf's custom log_buf behavior
selftests/bpf: Replace all uses of bpf_load_btf() with bpf_btf_load()
libbpf: Deprecate bpf_object__load_xattr()
libbpf: Add per-program log buffer setter and getter
libbpf: Preserve kernel error code and remove kprobe prog type guessing
libbpf: Improve logging around BPF program loading
libbpf: Allow passing user log setting through bpf_object_open_opts
libbpf: Allow passing preallocated log_buf when loading BTF into kernel
libbpf: Add OPTS-based bpf_btf_load() API
libbpf: Fix bpf_prog_load() log_buf logic for log_level 0
samples/bpf: Remove unneeded variable
bpf: Remove redundant assignment to pointer t
selftests/bpf: Fix a compilation warning
perf/bpf_counter: Use bpf_map_create instead of bpf_create_map
samples: bpf: Fix 'unknown warning group' build warning on Clang
samples: bpf: Fix xdp_sample_user.o linking with Clang
...
====================
Link: https://lore.kernel.org/r/20211210234746.2100561-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Libbpf development version was bumped to 0.7 in c93faaaf2f
("libbpf: Deprecate bpf_prog_load_xattr() API"), activating a bunch of
previously scheduled deprecations. Most APIs are pretty straightforward
to replace with newer APIs, but perf has a complicated mixed setup with
libbpf used both as static and shared configurations, which makes it
non-trivial to migrate the APIs.
Further, bpf_program__set_prep() needs more involved refactoring, which
will require help from Arnaldo and/or Jiri.
So for now, mute deprecation warnings and work on migrating perf off of
deprecated APIs separately with the input from owners of the perf tool.
Fixes: c93faaaf2f ("libbpf: Deprecate bpf_prog_load_xattr() API")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211203004640.2455717-1-andrii@kernel.org
For some time now the 'perf test 42: BPF filter' returns an error on bpf
relocation subtest, at least on x86 and s390. This is caused by
d859900c4c ("bpf, libbpf: support global data/bss/rodata sections")
which introduces support for global variables in eBPF programs.
Perf test 42.4 checks that the eBPF relocation fails when the eBPF program
contains a global variable. It returns OK when the eBPF program
could not be loaded and FAILED otherwise.
With above commit the test logic for the eBPF relocation is obsolete.
The loading of the eBPF now succeeds and the test always shows FAILED.
This patch removes the sub test completely.
Also a lot of eBPF program testing is done in the eBPF test suite,
it also contains tests for global variables.
Output before:
42: BPF filter :
42.1: Basic BPF filtering : Ok
42.2: BPF pinning : Ok
42.3: BPF prologue generation : Ok
42.4: BPF relocation checker : Failed
#
Output after:
# ./perf test -F 42
42: BPF filter :
42.1: Basic BPF filtering : Ok
42.2: BPF pinning : Ok
42.3: BPF prologue generation : Ok
#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20210324083734.1953123-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If either NO_LIBBPF=1 is passed, explicitely disabling it or if libbpf
is not available due to some missing dependency, skip its tests, telling
the user the feature isn't available.
# perf test
<SNIP>
40: LLVM search and compile : Skip (not compiled in)
41: Session topology : Ok
42: BPF filter : Skip (not compiled in)
<SNIP>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
BPF basic filtering test fails on s390x (when vmlinux debuginfo is
utilized instead of /proc/kallsyms)
Info:
- bpf_probe_load installs the bpf code at do_epoll_wait.
- For s390x, do_epoll_wait resolves to 3 functions including inlines.
found inline addr: 0x43769e
Probe point found: __s390_sys_epoll_wait+6
found inline addr: 0x437290
Probe point found: do_epoll_wait+0
found inline addr: 0x4375d6
Probe point found: __se_sys_epoll_wait+6
- add_bpf_event creates evsel for every probe in a BPF object. This
results in 3 evsels.
Solution:
- Expected result = 50% of the samples to be collected from epoll_wait *
number of entries present in the evlist.
Committer testing:
# perf test 42
42: BPF filter :
42.1: Basic BPF filtering : Ok
42.2: BPF pinning : Ok
42.3: BPF prologue generation : Ok
42.4: BPF relocation checker : Ok
#
Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: bpf@vger.kernel.org
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
LPU-Reference: 20200817072754.58344-1-sumanthk@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As this isn't used at all in mmap.h but in evlist.h, so to cut down the
header dependency tree, move it to where it is used.
Also add mmap.h to the places using it but previously getting it
indirectly via evlist.h.
Add missing pthread.h to evlist.h, as it has a pthread_t struct member
and was getting the header via mmap.h.
Noticed while processing a Jiri's libperf batch touching mmap.h, where
almost everything gets rebuilt because evlist.h is so popular, so cut
down't this rebuild the world party.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lkml.kernel.org/n/tip-he0uljeftl0xfveh3d6vtode@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'perf test bpf' was hooking a eBPF program on the SyS_epoll_wait()
kernel function, that was what the epoll_wait() glibc function ended up
calling, but since at least glibc 2.26, the one that comes with, for
instance, Fedora 27, glibc ends up calling SyS_epoll_pwait() when
epoll_wait() is used, causing this 'perf test' entry to fail.
So switch to using epoll_pwait() and hook the eBPF program to the
SyS_epoll_pwait() kernel function to make it work on a wider range of
glibc and kernel versions.
Tested-by: Wang Nan <wangnan0@huawei.com>
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>
Link: https://lkml.kernel.org/n/tip-zynvquy63er8s5mrgsz65pto@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When failing on one of the BPF tests we were just stating:
BPF filter result incorrect
Add some more info to help figuring out the problem:
BPF filter result incorrect, expected 56, got 0 samples
This came out while investigating this failure, first seen after
updating the kernel to the 4.15.0-rc6 tag:
[root@jouet ~]# perf test bpf
39: BPF filter :
39.1: Basic BPF filtering : FAILED!
39.2: BPF pinning : Skip
39.3: BPF prologue generation: Skip
39.4: BPF relocation checker : Skip
[root@jouet ~]#
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-403npu7daupv6b2bmxliv5pk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
