Add a simple expression parser good enough to parse JSON relation
expressions. The parser is implemented using bison.
This is just intended as an simple parser for internal usage in the
event lists, not the beginning of a "perf scripting language"
v2: Use expr__ prefix instead of expr_
Support multiple free variables for parser
Committer note:
The v2 patch had:
%define api.pure full
In expr.y, that is a feature introduced in bison 2.7, to have reentrant
parsers, not using global variables, which would make tools/perf stop
building with the bison version shipped in older distros, so Andi
realised that the other parsers (e.g. parse-events.y) were using:
%pure-parser
Which is present in older versions of bison and fits the bill.
I added:
CFLAGS_expr-bison.o += -DYYENABLE_NLS=0 -DYYLTYPE_IS_TRIVIAL=0 -w
To finally make it build, copying what was there for pmu-bison.o,
another parser.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-8-andi@firstfloor.org
[ stdlib.h is needed in tests/expr.c for free() fixing build in systems such as ubuntu:16.04-x-s390 ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are 2 problems wrt. cpu_topology_map on systems with sparse CPUs:
1. offline/absent CPUs will have their socket_id and core_id set to -1
which triggers:
"socket_id number is too big.You may need to upgrade the perf tool."
2. size of cpu_topology_map (perf_env.cpu[]) is allocated based on
_SC_NPROCESSORS_CONF, but can be indexed with CPU ids going above.
Users of perf_env.cpu[] are using CPU id as index. This can lead
to read beyond what was allocated:
==19991== Invalid read of size 4
==19991== at 0x490CEB: check_cpu_topology (topology.c:69)
==19991== by 0x490CEB: test_session_topology (topology.c:106)
...
For example:
_SC_NPROCESSORS_CONF == 16
available: 2 nodes (0-1)
node 0 cpus: 0 6 8 10 16 22 24 26
node 0 size: 12004 MB
node 0 free: 9470 MB
node 1 cpus: 1 7 9 11 23 25 27
node 1 size: 12093 MB
node 1 free: 9406 MB
node distances:
node 0 1
0: 10 20
1: 20 10
This patch changes HEADER_NRCPUS.nr_cpus_available from _SC_NPROCESSORS_CONF
to max_present_cpu and updates any user of cpu_topology_map to iterate
with nr_cpus_avail.
As a consequence HEADER_CPU_TOPOLOGY core_id and socket_id lists get longer,
but maintain compatibility with pre-patch state - index to cpu_topology_map is
CPU id.
perf test 36 -v
36: Session topology :
--- start ---
test child forked, pid 22211
templ file: /tmp/perf-test-gmdX5i
CPU 0, core 0, socket 0
CPU 1, core 0, socket 1
CPU 6, core 10, socket 0
CPU 7, core 10, socket 1
CPU 8, core 1, socket 0
CPU 9, core 1, socket 1
CPU 10, core 9, socket 0
CPU 11, core 9, socket 1
CPU 16, core 0, socket 0
CPU 22, core 10, socket 0
CPU 23, core 10, socket 1
CPU 24, core 1, socket 0
CPU 25, core 1, socket 1
CPU 26, core 9, socket 0
CPU 27, core 9, socket 1
test child finished with 0
---- end ----
Session topology: Ok
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/d7c05c6445fca74a8442c2c73cfffd349c52c44f.1487146877.git.jstancek@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
End result is the same, its an ABI, so the struct won't change, avoid
using a GNU extension, so that we can catch other cases that may be bugs.
Caught when building with clang:
tests/parse-no-sample-id-all.c:53:20: error: field 'attr' with variable sized type 'struct attr_event' not at the end of a struct or class is a GNU extension
[-Werror,-Wgnu-variable-sized-type-not-at-end]
struct attr_event attr;
^
1 error generated.
Testing it:
# perf test sample_id
24: Parse with no sample_id_all bit set : Ok
#
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: http://lkml.kernel.org/n/tip-e2vs1x771fc208uvxnwcf08b@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Addressing a few cases spotted by a new warning in gcc 7:
tests/parse-events.c: In function 'test_pmu_events':
tests/parse-events.c:1790:39: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size 90 [-Werror=format-truncation=]
snprintf(name, MAX_NAME, "cpu/event=%s/u", ent->d_name);
^~
In file included from /usr/include/stdio.h:939:0,
from /git/linux/tools/perf/util/map.h:9,
from /git/linux/tools/perf/util/symbol.h:7,
from /git/linux/tools/perf/util/evsel.h:10,
from tests/parse-events.c:3:
/usr/include/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 13 and 268 bytes into a destination of size 100
return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
__bos (__s), __fmt, __va_arg_pack ());
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tests/parse-events.c:1798:29: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size 100 [-Werror=format-truncation=]
snprintf(name, MAX_NAME, "%s:u,cpu/event=%s/u", ent->d_name, ent->d_name);
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>
Fixes: 945aea220b ("perf tests: Move test objects into 'tests' directory")
Link: http://lkml.kernel.org/n/tip-ty4q2p8zp1dp3mskvubxskm5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf fixes from Ingo Molnar:
"On the kernel side there's two x86 PMU driver fixes and a uprobes fix,
plus on the tooling side there's a number of fixes and some late
updates"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
perf sched timehist: Fix invalid period calculation
perf sched timehist: Remove hardcoded 'comm_width' check at print_summary
perf sched timehist: Enlarge default 'comm_width'
perf sched timehist: Honour 'comm_width' when aligning the headers
perf/x86: Fix overlap counter scheduling bug
perf/x86/pebs: Fix handling of PEBS buffer overflows
samples/bpf: Move open_raw_sock to separate header
samples/bpf: Remove perf_event_open() declaration
samples/bpf: Be consistent with bpf_load_program bpf_insn parameter
tools lib bpf: Add bpf_prog_{attach,detach}
samples/bpf: Switch over to libbpf
perf diff: Do not overwrite valid build id
perf annotate: Don't throw error for zero length symbols
perf bench futex: Fix lock-pi help string
perf trace: Check if MAP_32BIT is defined (again)
samples/bpf: Make perf_event_read() static
uprobes: Fix uprobes on MIPS, allow for a cache flush after ixol breakpoint creation
samples/bpf: Make samples more libbpf-centric
tools lib bpf: Add flags to bpf_create_map()
tools lib bpf: use __u32 from linux/types.h
...
Pull kbuild updates from Michal Marek:
- prototypes for x86 asm-exported symbols (Adam Borowski) and a warning
about missing CRCs (Nick Piggin)
- asm-exports fix for LTO (Nicolas Pitre)
- thin archives improvements (Nick Piggin)
- linker script fix for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION (Nick
Piggin)
- genksyms support for __builtin_va_list keyword
- misc minor fixes
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
x86/kbuild: enable modversions for symbols exported from asm
kbuild: fix scripts/adjust_autoksyms.sh* for the no modules case
scripts/kallsyms: remove last remnants of --page-offset option
make use of make variable CURDIR instead of calling pwd
kbuild: cmd_export_list: tighten the sed script
kbuild: minor improvement for thin archives build
kbuild: modpost warn if export version crc is missing
kbuild: keep data tables through dead code elimination
kbuild: improve linker compatibility with lib-ksyms.o build
genksyms: Regenerate parser
kbuild/genksyms: handle va_list type
kbuild: thin archives for multi-y targets
kbuild: kallsyms allow 3-pass generation if symbols size has changed
make already provides the current working directory in a variable, so make
use of it instead of forking a shell. Also replace usage of PWD by
CURDIR. PWD is provided by most shells, but not all, so this makes the
build system more robust.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
getBPFObjectFromModule() is introduced to compile LLVM IR(Module)
to BPF object. Add new testcase for it.
Test result:
$ ./buildperf/perf test -v clang
51: builtin clang support :
51.1: builtin clang compile C source to IR :
--- start ---
test child forked, pid 21822
test child finished with 0
---- end ----
builtin clang support subtest 0: Ok
51.2: builtin clang compile C source to ELF object :
--- start ---
test child forked, pid 21823
test child finished with 0
---- end ----
builtin clang support subtest 1: Ok
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Joe Stringer <joe@ovn.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-15-wangnan0@huawei.com
[ Remove redundant "Test" from entry descriptions ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add basic clang support in clang.cpp and test__clang() testcase. The
first testcase checks if builtin clang is able to generate LLVM IR.
tests/clang.c is a proxy. Real testcase resides in
utils/c++/clang-test.cpp in c++ and exports C interface to perf test
subsystem.
Test result:
$ perf test -v clang
51: builtin clang support :
51.1: Test builtin clang compile C source to IR :
--- start ---
test child forked, pid 13215
test child finished with 0
---- end ----
Test builtin clang support subtest 0: Ok
Committer note:
Make sure you've enabled CLANG and LLVM builtin support by setting
the LIBCLANGLLVM variable on the make command line, e.g.:
make LIBCLANGLLVM=1 O=/tmp/build/perf -C tools/perf install-bin
Otherwise you'll get this when trying to do the 'perf test' call above:
# perf test clang
51: builtin clang support : Skip (not compiled in)
#
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Joe Stringer <joe@ovn.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-11-wangnan0@huawei.com
[ Removed "Test" from descriptions, redundant and already removed from all the other entries ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Having "test" in almost all test descriptions is redundant, simplify it
removing and rewriting tests with such descriptions.
End result:
# 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: PERF_RECORD_* events & perf_sample fields : Ok
7: Parse perf pmu format : Ok
8: DSO data read : Ok
9: DSO data cache : Ok
10: DSO data reopen : Ok
11: Roundtrip evsel->name : Ok
12: Parse sched tracepoints fields : Ok
13: syscalls:sys_enter_openat event fields : Ok
14: Setup struct perf_event_attr : Ok
15: Match and link multiple hists : Ok
16: 'import perf' in python : Ok
17: Breakpoint overflow signal handler : Ok
18: Breakpoint overflow sampling : Ok
19: Number of exit events of a simple workload : Ok
20: Software clock events period values : Ok
21: Object code reading : Ok
22: Sample parsing : Ok
23: Use a dummy software event to keep tracking: Ok
24: Parse with no sample_id_all bit set : Ok
25: Filter hist entries : Ok
26: Lookup mmap thread : Ok
27: Share thread mg : Ok
28: Sort output of hist entries : Ok
29: Cumulate child hist entries : Ok
30: Track with sched_switch : Ok
31: Filter fds with revents mask in a fdarray : Ok
32: Add fd to a fdarray, making it autogrow : Ok
33: kmod_path__parse : Ok
34: Thread map : Ok
35: LLVM search and compile :
35.1: Basic BPF llvm compile : Ok
35.2: kbuild searching : Ok
35.3: Compile source for BPF prologue generation: Ok
35.4: Compile source for BPF relocation : Ok
36: Session topology : Ok
37: BPF filter :
37.1: Basic BPF filtering : Ok
37.2: BPF prologue generation : Ok
37.3: BPF relocation checker : Ok
38: Synthesize thread map : Ok
39: Synthesize cpu map : Ok
40: Synthesize stat config : Ok
41: Synthesize stat : Ok
42: Synthesize stat round : Ok
43: Synthesize attr update : Ok
44: Event times : Ok
45: Read backward ring buffer : Ok
46: Print cpu map : Ok
47: Probe SDT events : Ok
48: is_printable_array : Ok
49: Print bitmap : Ok
50: perf hooks : Ok
51: x86 rdpmc : Ok
52: Convert perf time to TSC : Ok
53: DWARF unwind : Ok
54: x86 instruction decoder - new instructions : Ok
55: Intel cqm nmi context read : Skip
#
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: http://lkml.kernel.org/n/tip-rx2lbfcrrio2yx1fxcljqy0e@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf hooks allow hooking user code at perf events. They can be used for
manipulation of BPF maps, taking snapshot and reporting results. In this
patch two perf hook points are introduced: record_start and record_end.
To avoid buggy user actions, a SIGSEGV signal handler is introduced into
'perf record'. It turns off perf hook if it causes a segfault and report
an error to help debugging.
A test case for perf hook is introduced.
Test result:
$ ./buildperf/perf test -v hook
50: Test perf hooks :
--- start ---
test child forked, pid 10311
SIGSEGV is observed as expected, try to recover.
Fatal error (SEGFAULT) in perf hook 'test'
test child finished with 0
---- end ----
Test perf hooks: Ok
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Joe Stringer <joe@ovn.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-5-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The algorithms used to prune aliases in symbols__fixup_duplicate() uses
information available on ELF symtabs that are not present on
/proc/kallsyms, so it picks different aliases as "best" for vmlinux and
kallsyms.
We could probably improve a bit this by having a list of aliases for the
"best" symbols picked, instead of throwing this info, but that is left
for when we find a real need.
With this, 'perf test vmlinux' passes:
# perf test -F 1
1: vmlinux symtab matches kallsyms: Ok
#
When we ask for verbose mode, we can see those warning:
# perf test -F -v 1
1: vmlinux symtab matches kallsyms:
--- start ---
Looking at the vmlinux_path (8 entries long)
Using /lib/modules/4.8.0-rc4+/build/vmlinux for symbols
WARN: 0xffffffffb7001000: diff name v: xen_hypercall_set_trap_table k: hypercall_page
WARN: 0xffffffffb7077970: diff end addr for aesni_gcm_dec v: 0xffffffffb707a2f2 k: 0xffffffffb7077a02
WARN: 0xffffffffb707a300: diff end addr for aesni_gcm_enc v: 0xffffffffb707cc03 k: 0xffffffffb707a392
WARN: 0xffffffffb707f950: diff end addr for aesni_gcm_enc_avx_gen2 v: 0xffffffffb7084ef6 k: 0xffffffffb707f9c3
WARN: 0xffffffffb7084f00: diff end addr for aesni_gcm_dec_avx_gen2 v: 0xffffffffb708a691 k: 0xffffffffb7084f73
WARN: 0xffffffffb708aa10: diff end addr for aesni_gcm_enc_avx_gen4 v: 0xffffffffb708f844 k: 0xffffffffb708aa83
WARN: 0xffffffffb708f850: diff end addr for aesni_gcm_dec_avx_gen4 v: 0xffffffffb709486f k: 0xffffffffb708f8c3
WARN: 0xffffffffb71a6e50: diff name v: perf_pmu_commit_txn.part.98 k: perf_pmu_cancel_txn.part.97
WARN: 0xffffffffb752e480: diff name v: wakeup_expire_count_show.part.5 k: wakeup_active_count_show.part.7
WARN: 0xffffffffb76e8d00: diff name v: phys_switch_id_show.part.11 k: phys_port_name_show.part.12
WARN: Maps only in vmlinux:
ffffffffb7d7d000-ffffffffb7eeaac8 117d000 [kernel].init.text
ffffffffb7eeaac8-ffffffffc03ad000 12eaac8 [kernel].exit.text
---- end ----
vmlinux symtab matches kallsyms: Ok
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-6v5w1k8rpx4ggczlkw730vt0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before:
# perf test -F -v 1
1: vmlinux symtab matches kallsyms:
--- start ---
<SNIP>
WARN: Maps only in vmlinux:
ffffffffb7d7d000-ffffffffb7eeaac8 117d000 [kernel].init.text
ffffffffb7eeaac8-ffffffffc03ad000 12eaac8 [kernel].exit.text
WARN: Maps in vmlinux with a different name in kallsyms:
WARN: Maps only in kallsyms:
---- end ----
vmlinux symtab matches kallsyms: Ok
#
The two last WARN lines are now suppressed, since there are no such
cases detected.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9ww8uvzl682ykaw8ht1tozlr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the 'perf test -v vmlinux' test fails, it is not clear which of the
lines are errors or warnings, clarify that adding ERR/WARN prefixes:
# perf test -F -v 1
1: vmlinux symtab matches kallsyms :
--- start ---
Looking at the vmlinux_path (8 entries long)
Using /lib/modules/4.8.0-rc4+/build/vmlinux for symbols
ERR : 0xffffffffb7001000: diff name v: xen_hypercall_set_trap_table k: hypercall_page
WARN: 0xffffffffb7077970: diff end addr for aesni_gcm_dec v: 0xffffffffb707a2f2 k: 0xffffffffb7077a02
WARN: 0xffffffffb707a300: diff end addr for aesni_gcm_enc v: 0xffffffffb707cc03 k: 0xffffffffb707a392
WARN: 0xffffffffb707f950: diff end addr for aesni_gcm_enc_avx_gen2 v: 0xffffffffb7084ef6 k: 0xffffffffb707f9c3
WARN: 0xffffffffb7084f00: diff end addr for aesni_gcm_dec_avx_gen2 v: 0xffffffffb708a691 k: 0xffffffffb7084f73
WARN: 0xffffffffb708aa10: diff end addr for aesni_gcm_enc_avx_gen4 v: 0xffffffffb708f844 k: 0xffffffffb708aa83
WARN: 0xffffffffb708f850: diff end addr for aesni_gcm_dec_avx_gen4 v: 0xffffffffb709486f k: 0xffffffffb708f8c3
ERR : 0xffffffffb71a6e50: diff name v: perf_pmu_commit_txn.part.98 k: perf_pmu_cancel_txn.part.97
ERR : 0xffffffffb752e480: diff name v: wakeup_expire_count_show.part.5 k: wakeup_active_count_show.part.7
ERR : 0xffffffffb76e8d00: diff name v: phys_switch_id_show.part.11 k: phys_port_name_show.part.12
WARN: Maps only in vmlinux:
ffffffffb7d7d000-ffffffffb7eeaac8 117d000 [kernel].init.text
ffffffffb7eeaac8-ffffffffc03ad000 12eaac8 [kernel].exit.text
WARN: Maps in vmlinux with a different name in kallsyms:
WARN: Maps only in kallsyms:
---- end ----
vmlinux symtab matches kallsyms: FAILED!
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-n5ml8m7y9x8kzvxt09ipku88@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Something made the sys_epoll_wait() function alias not to be found in
the vmlinux DWARF info, being found only in /proc/kallsyms, which made
the BPF perf tests to fail:
[root@jouet ~]# perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : FAILED!
37.2: Test BPF prologue generation : Skip
37.3: Test BPF relocation checker : Skip
[root@jouet ~]#
Using -v we can see it is failing to find DWARF info for the probed function,
sys_epoll_wait, which we can find in /proc/kallsyms but not in vmlinux with
CONFIG_DEBUG_INFO:
[root@jouet ~]# grep -w sys_epoll_wait /proc/kallsyms
ffffffffbd295b50 T sys_epoll_wait
[root@jouet ~]#
[root@jouet ~]# readelf -wi /lib/modules/4.7.0+/build/vmlinux | grep -w sys_epoll_wait
[root@jouet ~]#
If we try to use perf probe:
[root@jouet ~]# perf probe sys_epoll_wait
Failed to find debug information for address ffffffffbd295b50
Probe point 'sys_epoll_wait' not found.
Error: Failed to add events.
[root@jouet ~]#
It all works if we use SyS_epoll_wait, that is just an alias to the probed
function:
[root@jouet ~]# grep -i sys_epoll_wait /proc/kallsyms
ffffffffbd295b50 T SyS_epoll_wait
ffffffffbd295b50 T sys_epoll_wait
[root@jouet ~]#
So use it:
[root@jouet ~]# perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation : Ok
37.3: Test BPF relocation checker : Ok
[root@jouet ~]#
Further info:
[root@jouet ~]# gcc --version
gcc (GCC) 6.1.1 20160621 (Red Hat 6.1.1-3)
[acme@jouet linux]$ cat /etc/fedora-release
Fedora release 24 (Twenty Four)
Investigation as to why it fails is still underway, but it was always
going from sys_epoll_wait to SyS_epoll_wait when looking up the DWARF
info in vmlinux, and this is what is breaking now.
Switching to use SyS_epoll_wait allows this test to proceed and test the
BPF code it was designed for, so lets have this in to allow passing this
test while we fix the root cause.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.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: http://lkml.kernel.org/n/tip-7hekjp0bodwjbb419sl2b55h@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch allows following config terms and option:
Globally setting events to overwrite;
# perf record --overwrite ...
Set specific events to be overwrite or no-overwrite.
# perf record --event cycles/overwrite/ ...
# perf record --event cycles/no-overwrite/ ...
Add missing config terms and update the config term array size because
the longest string length has changed.
For overwritable events, it automatically selects attr.write_backward
since perf requires it to be backward for reading.
Test result:
# perf record --overwrite -e syscalls:*enter_nanosleep* usleep 1
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.011 MB perf.data (1 samples) ]
# perf evlist -v
syscalls:sys_enter_nanosleep: type: 2, size: 112, config: 0x134, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, write_backward: 1
# Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1468485287-33422-14-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a basic test case for SDT event support. This test scans an SDT
event in perftools and check whether the SDT event is correctly stored
into the buildid cache.
Here is an example:
----
$ perf test sdt -v
47: Test SDT event probing :
--- start ---
test child forked, pid 20732
Found 72 SDTs in /home/mhiramat/ksrc/linux/tools/perf/perf
Writing cache: %sdt_perf:test_target=test_target
Cache committed: 0
symbol:test_target file:(null) line:0 offset:0 return:0 lazy:(null)
test child finished with 0
---- end ----
Test SDT event probing: Ok
----
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146831796546.17065.1502584370844087537.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
