Em Mon, Jan 02, 2023 at 07:12:50PM +0530, Athira Rajeev escreveu: > > On 14-Dec-2022, at 9:21 PM, Arnaldo Carvalho de Melo <a...@kernel.org > > <mailto:a...@kernel.org>> wrote: > > Em Tue, Dec 13, 2022 at 03:21:03PM +0530, Athira Rajeev escreveu: > >>> On 13-Dec-2022, at 12:27 AM, Arnaldo Carvalho de Melo <a...@kernel.org > >>> <mailto:a...@kernel.org>> wrote: > >>> Em Thu, Nov 03, 2022 at 12:27:01PM +0530, Athira Rajeev escreveu: > >>>>> On 28-Oct-2022, at 9:12 PM, Kajol Jain <kj...@linux.ibm.com > >>>>> <mailto:kj...@linux.ibm.com>> wrote: > >>>>> > >>>>> Perf BPF filter test fails in environment where "kernel-debuginfo" > >>>>> is not installed. > >>>>> > >>>>> Test failure logs: > >>>>> <<>> > >>>>> 42: BPF filter : > >>>>> 42.1: Basic BPF filtering : Ok > >>>>> 42.2: BPF pinning : Ok > >>>>> 42.3: BPF prologue generation : FAILED! > >>>>> <<>> > >>>>> > >>>>> Enabling verbose option provided debug logs, which says debuginfo > >>>>> needs to be installed. Snippet of verbose logs: > >>>>> > >>>>> <<>> > >>>>> 42.3: BPF prologue generation : > >>>>> --- start --- > >>>>> test child forked, pid 28218 > >>>>> <<>> > >>>>> Rebuild with CONFIG_DEBUG_INFO=y, or install an appropriate debuginfo > >>>>> package. > >>>>> bpf_probe: failed to convert perf probe events > >>>>> Failed to add events selected by BPF > >>>>> test child finished with -1 > >>>>> ---- end ---- > >>>>> BPF filter subtest 3: FAILED! > >>>>> <<>> > >>>>> > >>>>> Here subtest, "BPF prologue generation" failed and > >>>>> logs shows debuginfo is needed. After installing > >>>>> kernel-debuginfo package, testcase passes. > >>>>> > >>>>> Subtest "BPF prologue generation" failed because, the "do_test" > >>>>> function returns "TEST_FAIL" without checking the error type > >>>>> returned by "parse_events_load_bpf_obj" function. > >>>>> Function parse_events_load_bpf_obj can also return error of type > >>>>> "-ENOENT" incase kernel-debuginfo package is not installed. Fix this > >>>>> by adding check for -ENOENT error. > >>>>> > >>>>> Test result after the patch changes: > >>>>> > >>>>> Test failure logs: > >>>>> <<>> > >>>>> 42: BPF filter : > >>>>> 42.1: Basic BPF filtering : Ok > >>>>> 42.2: BPF pinning : Ok > >>>>> 42.3: BPF prologue generation : Skip (clang/debuginfo isn't > >>>>> installed or environment missing BPF support) > >>>>> > >>>>> Fixes: ba1fae431e74bb42 ("perf test: Add 'perf test BPF'") > >>>>> Signed-off-by: Kajol Jain <kj...@linux.ibm.com > >>>>> <mailto:kj...@linux.ibm.com>> > >>>>> Reviewed-by: Madhavan Srinivasan <ma...@linux.ibm.com > >>>>> <mailto:ma...@linux.ibm.com>> > >>>>> --- > >>>>> tools/perf/tests/bpf.c | 6 +++++- > >>>>> 1 file changed, 5 insertions(+), 1 deletion(-) > >>>>> > >>>>> diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c > >>>>> index 17c023823713..57cecadc1da2 100644 > >>>>> --- a/tools/perf/tests/bpf.c > >>>>> +++ b/tools/perf/tests/bpf.c > >>>>> @@ -126,6 +126,10 @@ static int do_test(struct bpf_object *obj, int > >>>>> (*func)(void), > >>>>> > >>>>> err = parse_events_load_bpf_obj(&parse_state, > >>>>> &parse_state.list, obj, NULL); > >>>>> parse_events_error__exit(&parse_error); > >>>>> + if (err == -ENOENT) { > >>>>> + pr_debug("Failed to add events selected by BPF, > >>>>> debuginfo package not installed\n"); > >>>>> + return TEST_SKIP; > >>>>> + } > >>>> > >>>> Hi Kajol, > >>>> > >>>> Here, you have used ENOENT to skip the test. But there could be other > >>>> places in the code path for “parse_events_load_bpf_obj” > >>>> which also returns ENOENT. In that case, for any exit that returns > >>>> ENOENT, test will get skipped. > >>>> > >>>> Can we look at the logs, example we have this in commit logs: > >>>> > >>>> Rebuild with CONFIG_DEBUG_INFO=y, or install an appropriate debuginfo > >>>> package. > >>>> > >>>> so as to decide whether to skip for debug info ? > >>> > >>> Kajol? > > > >> Hi Arnaldo, looking for your suggestion on how to handle the case where > >> debuginfo is missing. > > > >> Here the bpf test fails because of missing debuginfo. The function > >> which goes through the debuginfo check is "parse_events_load_bpf_obj" > >> . parse_events_load_bpf_obj internally calls "open_debuginfo" which > >> returns ENOENT when debuginfo is missing. The patch fix from Kajol is > >> to skip the test using error code ENOENT for debuginfo. > > > > Lets see: > > > > root@roc-rk3399-pc:~# uname -a > > Linux roc-rk3399-pc 6.1.0-rc5-00123-g4dd7ff4a0311 #2 SMP PREEMPT Wed Nov 16 > > 19:55:11 UTC 2022 aarch64 aarch64 aarch64 GNU/Linux > > root@roc-rk3399-pc:~# perf probe -x ~/bin/perf open_debuginfo > > Added new event: > > probe_perf:open_debuginfo (on open_debuginfo in /home/acme/bin/perf) > > > > You can now use it in all perf tools, such as: > > > > perf record -e probe_perf:open_debuginfo -aR sleep 1 > > > > root@roc-rk3399-pc:~# > > > > root@roc-rk3399-pc:~# perf trace --call-graph=dwarf -a -e probe_perf:* perf > > test bpf > > 40: LLVM search and compile : > > 40.1: Basic BPF llvm compile : Ok > > 40.3: Compile source for BPF prologue generation : > > FAILED! > > 40.4: Compile source for BPF relocation : Ok > > 42: BPF filter : > > 42.1: Basic BPF filtering : > > 0.000 perf/38363 probe_perf:open_debuginfo(__probe_ip: 187650778659428) > > open_debuginfo (/home/acme/bin/perf) > > try_to_find_probe_trace_events (inlined) > > convert_to_probe_trace_events (inlined) > > convert_perf_probe_events > > (/home/acme/bin/perf) > > bpf__probe (/home/acme/bin/perf) > > parse_events_load_bpf_obj > > (/home/acme/bin/perf) > > do_test (/home/acme/bin/perf) > > FAILED! > > 42.2: BPF pinning : > > 5594.218 perf/38582 probe_perf:open_debuginfo(__probe_ip: 187650778659428) > > open_debuginfo (/home/acme/bin/perf) > > try_to_find_probe_trace_events (inlined) > > convert_to_probe_trace_events (inlined) > > convert_perf_probe_events > > (/home/acme/bin/perf) > > bpf__probe (/home/acme/bin/perf) > > parse_events_load_bpf_obj > > (/home/acme/bin/perf) > > do_test (/home/acme/bin/perf) > > FAILED! > > 42.3: BPF prologue generation : > > FAILED! > > 63: Test libpfm4 support : > > 99: perf stat --bpf-counters test : Skip > > 100: perf stat --bpf-counters --for-each-cgroup test : Skip > > root@roc-rk3399-pc:~# > > > > So that is the callchains leading to open_debuginfo(), perhaps we should > > return ENODATA at try_to_find_probe_trace_events() when open_debuginfo() > > fails? > > Hi Arnaldo, > > Thanks for the suggestions. I tried with changing return code to ENODATA when > open_debuginfo fails and will > send a separate patch addressing this change. > > > > > ⬢[acme@toolbox perf]$ find tools/perf/ -name "*.[ch]" | xargs grep > > try_to_find_probe_trace_events > > tools/perf/util/probe-event.c:static int > > try_to_find_probe_trace_events(struct perf_probe_event *pev, > > tools/perf/util/probe-event.c:static int > > try_to_find_probe_trace_events(struct perf_probe_event *pev, > > tools/perf/util/probe-event.c: ret = > > try_to_find_probe_trace_events(pev, tevs); > > ⬢[acme@toolbox perf]$ > > > > Also it returns ENOENT as well when not finding the probe point... There > > we should return perhaps ENOSYM? > > ENOSYM is not defined for all the archs. > > arch/parisc/include/uapi/asm/errno.h:#define ENOSYM 215 > /* symbol does not exist in executable */ > > So we need to make this error code generic to use in probe-event. Shall we > make this error code > generic for all archs to use ?
Try to find some other errno that is available everywhere and use instead, I think. - Arnaldo
