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Groups > linux.kernel > #1668021 > unrolled thread
| Started by | Arnaldo Carvalho de Melo <acme@kernel.org> |
|---|---|
| First post | 2017-06-16 21:30 +0200 |
| Last post | 2017-06-16 21:40 +0200 |
| Articles | 3 — 2 participants |
Back to article view | Back to linux.kernel
[GIT PULL 0/3] perf/urgent fixes Arnaldo Carvalho de Melo <acme@kernel.org> - 2017-06-16 21:30 +0200
[PATCH 1/3] perf evsel: Fix probing of precise_ip level for default cycles event Arnaldo Carvalho de Melo <acme@kernel.org> - 2017-06-16 21:30 +0200
Re: [GIT PULL 0/3] perf/urgent fixes Ingo Molnar <mingo@kernel.org> - 2017-06-16 21:40 +0200
| From | Arnaldo Carvalho de Melo <acme@kernel.org> |
|---|---|
| Date | 2017-06-16 21:30 +0200 |
| Subject | [GIT PULL 0/3] perf/urgent fixes |
| Message-ID | <tT56p-4r7-3@gated-at.bofh.it> |
Hi Ingo,
Please consider pulling,
- Arnaldo
Test results at the end of this message, as usual.
The following changes since commit 63f700aab4c11d46626de3cd051dae56cf7e9056:
Merge tag 'xtensa-20170612' of git://github.com/jcmvbkbc/linux-xtensa (2017-06-13 15:09:10 +0900)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-urgent-for-mingo-4.12-20170616
for you to fetch changes up to 9126cbbacecb8917bd0418809ef1d26616b2061e:
perf unwind: Report module before querying isactivation in dwfl unwind (2017-06-16 14:37:30 -0300)
----------------------------------------------------------------
perf/urgent fixes:
- Fix probing of precise_ip level for default cycles event, that
got broken recently on x86_64 when its arch code started
considering invalid requesting precise samples when not sampling
(i.e. when attr.sample_period == 0).
This also fixes another problem in s/390 where the precision
probing with sample_period == 0 returned precise_ip > 0, that
then, when setting up the real cycles event (not probing) would
return EOPNOTSUPP for precise_ip > 0 (as determined previously
by probing) and sample_period > 0.
These problems resulted in attr_precise not being set to the
highest precision available on x86.64 when no event was specified,
i.e. the canonical:
perf record ./workload
would end up using attr.precise_ip = 0. As a workaround this would
need to be done:
perf record -e cycles:P ./workload
And on s/390 it would plain not work, requiring using:
perf record -e cycles ./workload
as a workaround. (Arnaldo Carvalho de Melo)
- Fix perf build with ARCH=x86_64, when ARCH should be transformed
into ARCH=x86, just like with the main kernel Makefile and
tools/objtool's, i.e. use SRCARCH. (Jiada Wang)
- Avoid accessing uninitialized data structures when unwinding with
elfutils's libdw, making it more closely mimic libunwind's unwinder.
(Milian Wolff)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
----------------------------------------------------------------
Arnaldo Carvalho de Melo (1):
perf evsel: Fix probing of precise_ip level for default cycles event
Jiada Wang (1):
perf tools: Fix build with ARCH=x86_64
Milian Wolff (1):
perf unwind: Report module before querying isactivation in dwfl unwind
tools/perf/Makefile.config | 38 +++++++++++++++++++-------------------
tools/perf/Makefile.perf | 2 +-
tools/perf/arch/Build | 2 +-
tools/perf/pmu-events/Build | 4 ++--
tools/perf/tests/Build | 2 +-
tools/perf/tests/task-exit.c | 2 +-
tools/perf/util/evsel.c | 12 ++++++++++++
tools/perf/util/header.c | 2 +-
tools/perf/util/unwind-libdw.c | 8 ++++++++
9 files changed, 46 insertions(+), 26 deletions(-)
Test results:
The first ones are container (docker) based builds of tools/perf with and
without libelf support, objtool where it is supported and samples/bpf/, ditto.
Where clang is available, it is also used to build perf with/without libelf.
Several are cross builds, the ones with -x-ARCH, and the android one, and those
may not have all the features built, due to lack of multi-arch devel packages,
available and being used so far on just a few, like
debian:experimental-x-{arm64,mipsel}.
The 'perf test' one will perform a variety of tests exercising
tools/perf/util/, tools/lib/{bpf,traceevent,etc}, as well as run perf commands
with a variety of command line event specifications to then intercept the
sys_perf_event syscall to check that the perf_event_attr fields are set up as
expected, among a variety of other unit tests.
Then there is the 'make -C tools/perf build-test' ones, that build tools/perf/
with a variety of feature sets, exercising the build with an incomplete set of
features as well as with a complete one. It is planned to have it run on each
of the containers mentioned above, using some container orchestration
infrastructure. Get in contact if interested in helping having this in place.
# dm
1 alpine:3.4: Ok
2 alpine:3.5: Ok
3 alpine:3.6: Ok
4 alpine:edge: Ok
5 android-ndk:r12b-arm: Ok
6 archlinux:latest: Ok
7 centos:5: Ok
8 centos:6: Ok
9 centos:7: Ok
10 debian:7: Ok
11 debian:8: Ok
12 debian:9: Ok
13 debian:experimental: Ok
14 debian:experimental-x-arm64: Ok
15 debian:experimental-x-mips: Ok
16 debian:experimental-x-mips64: Ok
17 debian:experimental-x-mipsel: Ok
18 fedora:20: Ok
19 fedora:21: Ok
20 fedora:22: Ok
21 fedora:23: Ok
22 fedora:24: Ok
23 fedora:24-x-ARC-uClibc: Ok
24 fedora:25: Ok
25 fedora:rawhide: Ok
26 mageia:5: Ok
27 opensuse:13.2: Ok
28 opensuse:42.1: Ok
29 opensuse:tumbleweed: Ok
30 ubuntu:12.04.5: Ok
31 ubuntu:14.04.4: Ok
32 ubuntu:14.04.4-x-linaro-arm64: Ok
33 ubuntu:15.10: Ok
34 ubuntu:16.04: Ok
35 ubuntu:16.04-x-arm: Ok
36 ubuntu:16.04-x-arm64: Ok
37 ubuntu:16.04-x-powerpc: Ok
38 ubuntu:16.04-x-powerpc64: Ok
39 ubuntu:16.04-x-powerpc64el: Ok
40 ubuntu:16.04-x-s390: Ok
41 ubuntu:16.10: Ok
42 ubuntu:17.04: Ok
#
# uname -a
Linux jouet 4.12.0-rc4+ #1 SMP Fri Jun 9 12:59:23 -03 2017 x86_64 x86_64 x86_64 GNU/Linux
# perf test
1: vmlinux symtab matches kallsyms : Ok
2: Detect openat syscall event : Ok
3: Detect openat syscall event on all cpus : Ok
4: Read samples using the mmap interface : Ok
5: Parse event definition strings : Ok
6: Simple expression parser : Ok
7: PERF_RECORD_* events & perf_sample fields : Ok
8: Parse perf pmu format : Ok
9: DSO data read : Ok
10: DSO data cache : Ok
11: DSO data reopen : Ok
12: Roundtrip evsel->name : Ok
13: Parse sched tracepoints fields : Ok
14: syscalls:sys_enter_openat event fields : Ok
15: Setup struct perf_event_attr : Ok
16: Match and link multiple hists : Ok
17: 'import perf' in python : Ok
18: Breakpoint overflow signal handler : Ok
19: Breakpoint overflow sampling : Ok
20: Number of exit events of a simple workload : Ok
21: Software clock events period values : Ok
22: Object code reading : Ok
23: Sample parsing : Ok
24: Use a dummy software event to keep tracking: Ok
25: Parse with no sample_id_all bit set : Ok
26: Filter hist entries : Ok
27: Lookup mmap thread : Ok
28: Share thread mg : Ok
29: Sort output of hist entries : Ok
30: Cumulate child hist entries : Ok
31: Track with sched_switch : Ok
32: Filter fds with revents mask in a fdarray : Ok
33: Add fd to a fdarray, making it autogrow : Ok
34: kmod_path__parse : Ok
35: Thread map : Ok
36: LLVM search and compile :
36.1: Basic BPF llvm compile : Ok
36.2: kbuild searching : Ok
36.3: Compile source for BPF prologue generation: Ok
36.4: Compile source for BPF relocation : Ok
37: Session topology : Ok
38: BPF filter :
38.1: Basic BPF filtering : Ok
38.2: BPF pinning : Ok
38.3: BPF prologue generation : Ok
38.4: BPF relocation checker : Ok
39: Synthesize thread map : Ok
40: Remove thread map : Ok
41: Synthesize cpu map : Ok
42: Synthesize stat config : Ok
43: Synthesize stat : Ok
44: Synthesize stat round : Ok
45: Synthesize attr update : Ok
46: Event times : Ok
47: Read backward ring buffer : Ok
48: Print cpu map : Ok
49: Probe SDT events : Ok
50: is_printable_array : Ok
51: Print bitmap : Ok
52: perf hooks : Ok
53: builtin clang support : Skip (not compiled in)
54: unit_number__scnprintf : Ok
55: x86 rdpmc : Ok
56: Convert perf time to TSC : Ok
57: DWARF unwind : Ok
58: x86 instruction decoder - new instructions : Ok
59: Intel cqm nmi context read : Skip
#
$ make -C tools/perf build-test
make: Entering directory '/home/acme/git/linux/tools/perf'
- tarpkg: ./tests/perf-targz-src-pkg .
- /home/acme/git/linux/tools/perf/BUILD_TEST_FEATURE_DUMP: make FEATURE_DUMP_COPY=/home/acme/git/linux/tools/perf/BUILD_TEST_FEATURE_DUMP feature-dump
make_no_demangle_O: make NO_DEMANGLE=1
make_pure_O: make
make_no_backtrace_O: make NO_BACKTRACE=1
make_no_auxtrace_O: make NO_AUXTRACE=1
make_install_O: make install
make_no_libunwind_O: make NO_LIBUNWIND=1
make_no_libpython_O: make NO_LIBPYTHON=1
make_doc_O: make doc
make_no_libbionic_O: make NO_LIBBIONIC=1
make_no_gtk2_O: make NO_GTK2=1
make_no_libperl_O: make NO_LIBPERL=1
make_no_libbpf_O: make NO_LIBBPF=1
make_with_clangllvm_O: make LIBCLANGLLVM=1
make_no_libaudit_O: make NO_LIBAUDIT=1
make_install_prefix_O: make install prefix=/tmp/krava
make_util_map_o_O: make util/map.o
make_debug_O: make DEBUG=1
make_clean_all_O: make clean all
make_no_scripts_O: make NO_LIBPYTHON=1 NO_LIBPERL=1
make_minimal_O: make NO_LIBPERL=1 NO_LIBPYTHON=1 NO_NEWT=1 NO_GTK2=1 NO_DEMANGLE=1 NO_LIBELF=1 NO_LIBUNWIND=1 NO_BACKTRACE=1 NO_LIBNUMA=1 NO_LIBAUDIT=1 NO_LIBBIONIC=1 NO_LIBDW_DWARF_UNWIND=1 NO_AUXTRACE=1 NO_LIBBPF=1 NO_LIBCRYPTO=1 NO_SDT=1 NO_JVMTI=1
make_no_libnuma_O: make NO_LIBNUMA=1
make_install_prefix_slash_O: make install prefix=/tmp/krava/
make_no_slang_O: make NO_SLANG=1
make_no_libdw_dwarf_unwind_O: make NO_LIBDW_DWARF_UNWIND=1
make_perf_o_O: make perf.o
make_tags_O: make tags
make_util_pmu_bison_o_O: make util/pmu-bison.o
make_with_babeltrace_O: make LIBBABELTRACE=1
make_help_O: make help
make_no_ui_O: make NO_NEWT=1 NO_SLANG=1 NO_GTK2=1
make_install_bin_O: make install-bin
make_no_newt_O: make NO_NEWT=1
make_static_O: make LDFLAGS=-static
make_no_libelf_O: make NO_LIBELF=1
OK
make: Leaving directory '/home/acme/git/linux/tools/perf'
$
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| From | Arnaldo Carvalho de Melo <acme@kernel.org> |
|---|---|
| Date | 2017-06-16 21:30 +0200 |
| Subject | [PATCH 1/3] perf evsel: Fix probing of precise_ip level for default cycles event |
| Message-ID | <tT56r-4r7-27@gated-at.bofh.it> |
| In reply to | #1668021 |
From: Arnaldo Carvalho de Melo <acme@redhat.com>
Since commit 18e7a45af91a ("perf/x86: Reject non sampling events with
precise_ip") returns -EINVAL for sys_perf_event_open() with an attribute
with (attr.precise_ip > 0 && attr.sample_period == 0), just like is done
in the routine used to probe the max precise level when no events were
passed to 'perf record' or 'perf top', i.e.:
perf_evsel__new_cycles()
perf_event_attr__set_max_precise_ip()
The x86 code, in x86_pmu_hw_config(), which is called all the way from
sys_perf_event_open() did, starting with the aforementioned commit:
/* There's no sense in having PEBS for non sampling events: */
if (!is_sampling_event(event))
return -EINVAL;
Which makes it fail for cycles:ppp, cycles:pp and cycles:p, always using
just the non precise cycles variant.
To make sure that this is the case, I tested it, before this patch,
with:
# perf probe -L x86_pmu_hw_config
<x86_pmu_hw_config@/home/acme/git/linux/arch/x86/events/core.c:0>
0 int x86_pmu_hw_config(struct perf_event *event)
1 {
2 if (event->attr.precise_ip) {
<SNIP>
17 if (event->attr.precise_ip > precise)
18 return -EOPNOTSUPP;
/* There's no sense in having PEBS for non sampling events: */
21 if (!is_sampling_event(event))
22 return -EINVAL;
}
<SNIP>
# perf probe x86_pmu_hw_config:22
Added new events:
probe:x86_pmu_hw_config (on x86_pmu_hw_config:22)
probe:x86_pmu_hw_config_1 (on x86_pmu_hw_config:22)
You can now use it in all perf tools, such as:
perf record -e probe:x86_pmu_hw_config_1 -aR sleep 1
# perf trace -e perf_event_open,probe:x86_pmu_hwconfig*/max-stack=16/ perf record usleep 1
0.000 ( 0.015 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8ba110, cpu: -1, group_fd: -1 ) ...
0.015 ( ): probe:x86_pmu_hw_config:(ffffffff9c0065e1))
x86_pmu_hw_config ([kernel.kallsyms])
hsw_hw_config ([kernel.kallsyms])
x86_pmu_event_init ([kernel.kallsyms])
perf_try_init_event ([kernel.kallsyms])
perf_event_alloc ([kernel.kallsyms])
SYSC_perf_event_open ([kernel.kallsyms])
sys_perf_event_open ([kernel.kallsyms])
do_syscall_64 ([kernel.kallsyms])
return_from_SYSCALL_64 ([kernel.kallsyms])
syscall (/usr/lib64/libc-2.24.so)
perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
perf_evsel__new_cycles (/home/acme/bin/perf)
perf_evlist__add_default (/home/acme/bin/perf)
cmd_record (/home/acme/bin/perf)
run_builtin (/home/acme/bin/perf)
handle_internal_command (/home/acme/bin/perf)
0.000 ( 0.021 ms): perf/4150 ... [continued]: perf_event_open()) = -1 EINVAL Invalid argument
0.023 ( 0.002 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8ba110, cpu: -1, group_fd: -1 ) ...
0.025 ( ): probe:x86_pmu_hw_config:(ffffffff9c0065e1))
x86_pmu_hw_config ([kernel.kallsyms])
hsw_hw_config ([kernel.kallsyms])
x86_pmu_event_init ([kernel.kallsyms])
perf_try_init_event ([kernel.kallsyms])
perf_event_alloc ([kernel.kallsyms])
SYSC_perf_event_open ([kernel.kallsyms])
sys_perf_event_open ([kernel.kallsyms])
do_syscall_64 ([kernel.kallsyms])
return_from_SYSCALL_64 ([kernel.kallsyms])
syscall (/usr/lib64/libc-2.24.so)
perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
perf_evsel__new_cycles (/home/acme/bin/perf)
perf_evlist__add_default (/home/acme/bin/perf)
cmd_record (/home/acme/bin/perf)
run_builtin (/home/acme/bin/perf)
handle_internal_command (/home/acme/bin/perf)
0.023 ( 0.004 ms): perf/4150 ... [continued]: perf_event_open()) = -1 EINVAL Invalid argument
0.028 ( 0.002 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8ba110, cpu: -1, group_fd: -1 ) ...
0.030 ( ): probe:x86_pmu_hw_config:(ffffffff9c0065e1))
x86_pmu_hw_config ([kernel.kallsyms])
hsw_hw_config ([kernel.kallsyms])
x86_pmu_event_init ([kernel.kallsyms])
perf_try_init_event ([kernel.kallsyms])
perf_event_alloc ([kernel.kallsyms])
SYSC_perf_event_open ([kernel.kallsyms])
sys_perf_event_open ([kernel.kallsyms])
do_syscall_64 ([kernel.kallsyms])
return_from_SYSCALL_64 ([kernel.kallsyms])
syscall (/usr/lib64/libc-2.24.so)
perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
perf_evsel__new_cycles (/home/acme/bin/perf)
perf_evlist__add_default (/home/acme/bin/perf)
cmd_record (/home/acme/bin/perf)
run_builtin (/home/acme/bin/perf)
handle_internal_command (/home/acme/bin/perf)
0.028 ( 0.004 ms): perf/4150 ... [continued]: perf_event_open()) = -1 EINVAL Invalid argument
41.018 ( 0.012 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8b5dd0, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
41.065 ( 0.011 ms): perf/4150 perf_event_open(attr_uptr: 0x3c7db78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
41.080 ( 0.006 ms): perf/4150 perf_event_open(attr_uptr: 0x3c7db78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
41.103 ( 0.010 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), group_fd: -1, flags: FD_CLOEXEC) = 4
41.115 ( 0.006 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 5
41.122 ( 0.004 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 6
41.128 ( 0.008 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 8
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
#
I.e. that return -EINVAL in x86_pmu_hw_config() is hit three times.
So fix it by just setting attr.sample_period
Now, after this patch:
# perf trace --max-stack=2 -e perf_event_open,probe:x86_pmu_hw_config* perf record usleep 1
[ perf record: Woken up 1 times to write data ]
0.000 ( 0.017 ms): perf/8469 perf_event_open(attr_uptr: 0x7ffe36c27d10, pid: -1, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 4
syscall (/usr/lib64/libc-2.24.so)
perf_event_open_cloexec_flag (/home/acme/bin/perf)
0.050 ( 0.031 ms): perf/8469 perf_event_open(attr_uptr: 0x24ebb78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
syscall (/usr/lib64/libc-2.24.so)
perf_evlist__config (/home/acme/bin/perf)
0.092 ( 0.040 ms): perf/8469 perf_event_open(attr_uptr: 0x24ebb78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
syscall (/usr/lib64/libc-2.24.so)
perf_evlist__config (/home/acme/bin/perf)
0.143 ( 0.007 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, cpu: -1, group_fd: -1 ) = 4
syscall (/usr/lib64/libc-2.24.so)
perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
0.161 ( 0.007 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), group_fd: -1, flags: FD_CLOEXEC) = 4
syscall (/usr/lib64/libc-2.24.so)
perf_evsel__open (/home/acme/bin/perf)
0.171 ( 0.005 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 5
syscall (/usr/lib64/libc-2.24.so)
perf_evsel__open (/home/acme/bin/perf)
0.180 ( 0.007 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 6
syscall (/usr/lib64/libc-2.24.so)
perf_evsel__open (/home/acme/bin/perf)
0.190 ( 0.005 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 8
syscall (/usr/lib64/libc-2.24.so)
perf_evsel__open (/home/acme/bin/perf)
[ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ]
#
The probe one called from perf_event_attr__set_max_precise_ip() works
the first time, with attr.precise_ip = 3, wit hthe next ones being the
per cpu ones for the cycles:ppp event.
And here is the text from a report and alternative proposed patch by
Thomas-Mich Richter:
---
On s390 the counter and sampling facility do not support a precise IP
skid level and sometimes returns EOPNOTSUPP when structure member
precise_ip in struct perf_event_attr is not set to zero.
On s390 commnd 'perf record -- true' fails with error EOPNOTSUPP. This
happens only when no events are specified on command line.
The functions called are
...
--> perf_evlist__add_default
--> perf_evsel__new_cycles
--> perf_event_attr__set_max_precise_ip
The last function determines the value of structure member precise_ip by
invoking the perf_event_open() system call and checking the return code.
The first successful open is the value for precise_ip.
However the value is determined without setting member sample_period and
indicates no sampling.
On s390 the counter facility and sampling facility are different. The
above procedure determines a precise_ip value of 3 using the counter
facility. Later it uses the sampling facility with a value of 3 and
fails with EOPNOTSUPP.
---
v2: Older compilers (e.g. gcc 4.4.7) don't support referencing members
of unnamed union members in the container struct initialization, so
move from:
struct perf_event_attr attr = {
...
.sample_period = 1,
};
to right after it as:
struct perf_event_attr attr = {
...
};
attr.sample_period = 1;
v3: We need to reset .sample_period to 0 to let the users of
perf_evsel__new_cycles() to properly setup attr.sample_period or
attr.sample_freq. Reported by Ingo Molnar.
Reported-and-Acked-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 18e7a45af91a ("perf/x86: Reject non sampling events with precise_ip")
Link: http://lkml.kernel.org/n/tip-yv6nnkl7tzqocrm0hl3x7vf1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/tests/task-exit.c | 2 +-
tools/perf/util/evsel.c | 12 ++++++++++++
2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/tools/perf/tests/task-exit.c b/tools/perf/tests/task-exit.c
index 32873ec91a4e..cf00ebad2ef5 100644
--- a/tools/perf/tests/task-exit.c
+++ b/tools/perf/tests/task-exit.c
@@ -83,7 +83,7 @@ int test__task_exit(int subtest __maybe_unused)
evsel = perf_evlist__first(evlist);
evsel->attr.task = 1;
- evsel->attr.sample_freq = 0;
+ evsel->attr.sample_freq = 1;
evsel->attr.inherit = 0;
evsel->attr.watermark = 0;
evsel->attr.wakeup_events = 1;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index e4f7902d5afa..cda44b0e821c 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -273,8 +273,20 @@ struct perf_evsel *perf_evsel__new_cycles(void)
struct perf_evsel *evsel;
event_attr_init(&attr);
+ /*
+ * Unnamed union member, not supported as struct member named
+ * initializer in older compilers such as gcc 4.4.7
+ *
+ * Just for probing the precise_ip:
+ */
+ attr.sample_period = 1;
perf_event_attr__set_max_precise_ip(&attr);
+ /*
+ * Now let the usual logic to set up the perf_event_attr defaults
+ * to kick in when we return and before perf_evsel__open() is called.
+ */
+ attr.sample_period = 0;
evsel = perf_evsel__new(&attr);
if (evsel == NULL)
--
2.9.4
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| From | Ingo Molnar <mingo@kernel.org> |
|---|---|
| Date | 2017-06-16 21:40 +0200 |
| Message-ID | <tT5g5-4wK-3@gated-at.bofh.it> |
| In reply to | #1668021 |
* Arnaldo Carvalho de Melo <acme@kernel.org> wrote: > Hi Ingo, > > Please consider pulling, > > - Arnaldo > > Test results at the end of this message, as usual. > > The following changes since commit 63f700aab4c11d46626de3cd051dae56cf7e9056: > > Merge tag 'xtensa-20170612' of git://github.com/jcmvbkbc/linux-xtensa (2017-06-13 15:09:10 +0900) > > are available in the git repository at: > > git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-urgent-for-mingo-4.12-20170616 > > for you to fetch changes up to 9126cbbacecb8917bd0418809ef1d26616b2061e: > > perf unwind: Report module before querying isactivation in dwfl unwind (2017-06-16 14:37:30 -0300) > > ---------------------------------------------------------------- > perf/urgent fixes: > > - Fix probing of precise_ip level for default cycles event, that > got broken recently on x86_64 when its arch code started > considering invalid requesting precise samples when not sampling > (i.e. when attr.sample_period == 0). > > This also fixes another problem in s/390 where the precision > probing with sample_period == 0 returned precise_ip > 0, that > then, when setting up the real cycles event (not probing) would > return EOPNOTSUPP for precise_ip > 0 (as determined previously > by probing) and sample_period > 0. > > These problems resulted in attr_precise not being set to the > highest precision available on x86.64 when no event was specified, > i.e. the canonical: > > perf record ./workload > > would end up using attr.precise_ip = 0. As a workaround this would > need to be done: > > perf record -e cycles:P ./workload > > And on s/390 it would plain not work, requiring using: > > perf record -e cycles ./workload > > as a workaround. (Arnaldo Carvalho de Melo) > > - Fix perf build with ARCH=x86_64, when ARCH should be transformed > into ARCH=x86, just like with the main kernel Makefile and > tools/objtool's, i.e. use SRCARCH. (Jiada Wang) > > - Avoid accessing uninitialized data structures when unwinding with > elfutils's libdw, making it more closely mimic libunwind's unwinder. > (Milian Wolff) > > Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> > > ---------------------------------------------------------------- > Arnaldo Carvalho de Melo (1): > perf evsel: Fix probing of precise_ip level for default cycles event > > Jiada Wang (1): > perf tools: Fix build with ARCH=x86_64 > > Milian Wolff (1): > perf unwind: Report module before querying isactivation in dwfl unwind > > tools/perf/Makefile.config | 38 +++++++++++++++++++------------------- > tools/perf/Makefile.perf | 2 +- > tools/perf/arch/Build | 2 +- > tools/perf/pmu-events/Build | 4 ++-- > tools/perf/tests/Build | 2 +- > tools/perf/tests/task-exit.c | 2 +- > tools/perf/util/evsel.c | 12 ++++++++++++ > tools/perf/util/header.c | 2 +- > tools/perf/util/unwind-libdw.c | 8 ++++++++ > 9 files changed, 46 insertions(+), 26 deletions(-) Pulled, thanks a lot Arnaldo! Ingo
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