I forgot to fill in the map_symbol->maps field in append_inlines() which
then makes code down the line segfault when trying to deref it.
It doesn't make any sense to have an addr_location with its 'map' member
not NULL while its 'maps' is NULL, after all al->maps is where al->map
is in.
It is done that way so that we don't have to have in each 'struct map' a
pointer to the 'struct maps' it is in, as we had in the past when we
would have 'map->mg', before 'struct maps' was combined with 'struct
map_groups', because there was always a one-to-one relationship for
these structs.
This fixes a segfault when processing DWARF callgraphs in 'perf report'.
Reported-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 08f6680e62 ("perf tools: Add a 'struct map_groups' pointer to 'struct map_symbol'")
Link: http://lore.kernel.org/lkml/20191129160631.GD26963@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Restructure event enabling/disabling to use affinity, which
minimizes the number of IPIs needed.
Before on a large test case with 94 CPUs:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
54.65 1.899986 22 84812 660 ioctl
after:
39.21 0.930451 10 84796 644 ioctl
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-13-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Restructure event reading to use affinity to minimize the number of IPIs
needed.
Before on a large test case with 94 CPUs:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
3.16 0.106079 4 22082 read
After:
3.43 0.081295 3 22082 read
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-11-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Restructure the event opening in perf stat to cycle through the events
by CPU after setting affinity to that CPU.
This eliminates IPI overhead in the perf API.
We have to loop through the CPU in the outter builtin-stat code instead
of leaving that to low level functions.
It has to change the weak group fallback strategy slightly. Since we
cannot easily undo the opens for other CPUs move the weak group retry to
a separate loop.
Before with a large test case with 94 CPUs:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
42.75 4.050910 67 60046 110 perf_event_open
After:
26.86 0.944396 16 58069 110 perf_event_open
(the number changes slightly because the weak group retries
work differently and the test case relies on weak groups)
Committer notes:
Added one of the hunks in a patch provided by Andi after I noticed that
the "event times" 'perf test' entry was segfaulting.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-10-andi@firstfloor.org
Link: http://lore.kernel.org/lkml/20191127232657.GL84886@tassilo.jf.intel.com # Fix
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Closing a perf fd can also trigger an IPI to the target CPU.
Use the same affinity technique as we use for reading/enabling events to
closing to optimize the CPU transitions.
Before on a large test case with 94 CPUs:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
32.56 3.085463 50 61483 close
After:
10.54 0.735704 11 61485 close
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-8-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Maintain a cpumap in the evlist that is the union of all the cpus of the
events.
This needs a cpumap merge operation, which is added together with tests.
v2:
Add tests for cpu map merge
Fix handling of duplicates
Rename _update to _merge
Factor out sorting.
Fix handling of NULL maps in merge
v3:
Add comments and empty lines to _merge
Committer testing:
# perf test "Merge cpu map"
52: Merge cpu map : Ok
#
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lore.kernel.org/lkml/20191121001522.180827-5-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
brstackinsn must be allowed to be set by the user when AUX area data has
been captured because, in that case, the branch stack might be
synthesized on the fly. This fixes the following error:
Before:
$ perf record -e '{intel_pt//,cpu/mem_inst_retired.all_loads,aux-sample-size=8192/pp}:u' grep -rqs jhgjhg /boot
[ perf record: Woken up 19 times to write data ]
[ perf record: Captured and wrote 2.274 MB perf.data ]
$ perf script -F +brstackinsn --xed --itrace=i1usl100 | head
Display of branch stack assembler requested, but non all-branch filter set
Hint: run 'perf record -b ...'
After:
$ perf record -e '{intel_pt//,cpu/mem_inst_retired.all_loads,aux-sample-size=8192/pp}:u' grep -rqs jhgjhg /boot
[ perf record: Woken up 19 times to write data ]
[ perf record: Captured and wrote 2.274 MB perf.data ]
$ perf script -F +brstackinsn --xed --itrace=i1usl100 | head
grep 13759 [002] 8091.310257: 1862 instructions:uH: 5641d58069eb bmexec+0x86b (/bin/grep)
bmexec+2485:
00005641d5806b35 jnz 0x5641d5806bd0 # MISPRED
00005641d5806bd0 movzxb (%r13,%rdx,1), %eax
00005641d5806bd6 add %rdi, %rax
00005641d5806bd9 movzxb -0x1(%rax), %edx
00005641d5806bdd cmp %rax, %r14
00005641d5806be0 jnb 0x5641d58069c0 # MISPRED
mismatch of LBR data and executable
00005641d58069c0 movzxb (%r13,%rdx,1), %edi
Fixes: 48d02a1d5c ("perf script: Add 'brstackinsn' for branch stacks")
Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191127095322.15417-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The kernel perf subsystem has to IPI to the target CPU for many
operations. On systems with many CPUs and when managing many events the
overhead can be dominated by lots of IPIs.
An alternative is to set up CPU affinity in the perf tool, then set up
all the events for that CPU, and then move on to the next CPU.
Add some affinity management infrastructure to enable such a model.
Used in followon patches.
Committer notes:
Use zfree() in some places, add missing stdbool.h header, some minor
coding style changes.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-3-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
pmu.c does a lot of redundant /sys accesses while parsing aliases
and probing for PMUs. On large systems with a lot of PMUs this
can get expensive (>2s):
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
27.25 1.227847 8 160888 16976 openat
26.42 1.190481 7 164224 164077 stat
Add a cache to remember if specific file names exist or don't
exist, which eliminates most of this overhead.
Also optimize some stat() calls to be slightly cheaper access()
Resulting in:
0.18 0.004166 2 1851 305 open
0.08 0.001970 2 829 622 access
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-2-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To avoid breaking the build on arches where this is not wired up, at
least all the other features should be made available and when using
this specific routine, the "unknown" should point the user/developer to
the need to wire this up on this particular hardware architecture.
Detected in a container mipsel debian cross build environment, where it
shows up as:
In file included from /usr/mipsel-linux-gnu/include/stdio.h:867,
from /git/linux/tools/perf/lib/include/perf/cpumap.h:6,
from util/session.c:13:
In function 'printf',
inlined from 'regs_dump__printf' at util/session.c:1103:3,
inlined from 'regs__printf' at util/session.c:1131:2:
/usr/mipsel-linux-gnu/include/bits/stdio2.h:107:10: error: '%-5s' directive argument is null [-Werror=format-overflow=]
107 | return __printf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ());
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cross compiler details:
mipsel-linux-gnu-gcc (Debian 9.2.1-8) 9.2.1 20190909
Also on mips64:
In file included from /usr/mips64-linux-gnuabi64/include/stdio.h:867,
from /git/linux/tools/perf/lib/include/perf/cpumap.h:6,
from util/session.c:13:
In function 'printf',
inlined from 'regs_dump__printf' at util/session.c:1103:3,
inlined from 'regs__printf' at util/session.c:1131:2,
inlined from 'regs_user__printf' at util/session.c:1139:3,
inlined from 'dump_sample' at util/session.c:1246:3,
inlined from 'machines__deliver_event' at util/session.c:1421:3:
/usr/mips64-linux-gnuabi64/include/bits/stdio2.h:107:10: error: '%-5s' directive argument is null [-Werror=format-overflow=]
107 | return __printf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ());
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function 'printf',
inlined from 'regs_dump__printf' at util/session.c:1103:3,
inlined from 'regs__printf' at util/session.c:1131:2,
inlined from 'regs_intr__printf' at util/session.c:1147:3,
inlined from 'dump_sample' at util/session.c:1249:3,
inlined from 'machines__deliver_event' at util/session.c:1421:3:
/usr/mips64-linux-gnuabi64/include/bits/stdio2.h:107:10: error: '%-5s' directive argument is null [-Werror=format-overflow=]
107 | return __printf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ());
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cross compiler details:
mips64-linux-gnuabi64-gcc (Debian 9.2.1-8) 9.2.1 20190909
Fixes: 2bcd355b71 ("perf tools: Add interface to arch registers sets")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-95wjyv4o65nuaeweq31t7l1s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To fix this build error on a debian mipsel cross build environment:
builtin-diff.c: In function 'compute_cycles_diff':
builtin-diff.c:649:10: error: absolute value function 'labs' given an argument of type 's64' {aka 'long long int'} but has parameter of type 'long int' which may cause truncation of value [-Werror=absolute-value]
649 | val = labs(pair->block_info->cycles_spark[i] -
| ^~~~
Fixes: cebf7d51a6 ("perf diff: Report noisy for cycles diff")
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-pn7szy5uw384ntjgk6zckh6a@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To fix these build errors on a debian mipsel cross build environment:
builtin-diff.c: In function 'block_cycles_diff_cmp':
builtin-diff.c:550:6: error: absolute value function 'labs' given an argument of type 's64' {aka 'long long int'} but has parameter of type 'long int' which may cause truncation of value [-Werror=absolute-value]
550 | l = labs(left->diff.cycles);
| ^~~~
builtin-diff.c:551:6: error: absolute value function 'labs' given an argument of type 's64' {aka 'long long int'} but has parameter of type 'long int' which may cause truncation of value [-Werror=absolute-value]
551 | r = labs(right->diff.cycles);
| ^~~~
Fixes: 99150a1faa ("perf diff: Use hists to manage basic blocks per symbol")
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-pn7szy5uw384ntjgk6zckh6a@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
$ make -C tools/perf build-test
does, ends up with these two problems:
make[3]: *** No rule to make target '/tmp/tmp.zq13cHILGB/perf-5.3.0/include/uapi/linux/bpf.h', needed by 'bpf_helper_defs.h'. Stop.
make[3]: *** Waiting for unfinished jobs....
make[2]: *** [Makefile.perf:757: /tmp/tmp.zq13cHILGB/perf-5.3.0/tools/lib/bpf/libbpf.a] Error 2
make[2]: *** Waiting for unfinished jobs....
Because $(srcdir) points to the /tmp/tmp.zq13cHILGB/perf-5.3.0 directory
and we need '/tools/ after that variable, and after fixing this then we
get to another problem:
/bin/sh: /home/acme/git/perf/tools/scripts/bpf_helpers_doc.py: No such file or directory
make[3]: *** [Makefile:184: bpf_helper_defs.h] Error 127
make[3]: *** Deleting file 'bpf_helper_defs.h'
LD /tmp/build/perf/libapi-in.o
make[2]: *** [Makefile.perf:778: /tmp/build/perf/libbpf.a] Error 2
make[2]: *** Waiting for unfinished jobs....
Because this requires something outside the tools/ directories that gets
collected into perf's detached tarballs, to fix it just add it to
tools/perf/MANIFEST, which this patch does, now it works for that case
and also for all these other cases.
Fixes: e01a75c159 ("libbpf: Move bpf_{helpers, helper_defs, endian, tracing}.h into libbpf")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-4pnkg2vmdvq5u6eivc887wen@git.kernel.org
Link: https://lore.kernel.org/bpf/20191126151045.GB19483@kernel.org
Currently we support only static linking with kernel's libbpf
(tools/lib/bpf). This patch adds libbpf package detection and support to
link perf with it dynamically.
The libbpf package status is displayed with:
$ make VF=1
Auto-detecting system features:
...
... libbpf: [ on ]
It's not checked by default, because it's quite new. Once it's on most
distros we can switch it on.
For the same reason it's not added to the test-all check.
Perf does not need advanced version of libbpf, so we can check just for
the base bpf_object__open function.
Adding new compile variable to detect libbpf package and link bpf
dynamically:
$ make LIBBPF_DYNAMIC=1
...
LINK perf
$ ldd perf | grep bpf
libbpf.so.0 => /lib64/libbpf.so.0 (0x00007f46818bc000)
If libbpf is not installed, build stops with:
Makefile.config:486: *** Error: No libbpf devel library found,\
please install libbpf-devel. Stop.
Committer testing:
$ make LIBBPF_DYNAMIC=1 -C tools/perf O=/tmp/build/perf
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build
Makefile.config:493: *** Error: No libbpf devel library found, please install libbpf-devel. Stop.
make[1]: *** [Makefile.perf:225: sub-make] Error 2
make: *** [Makefile:70: all] Error 2
make: Leaving directory '/home/acme/git/perf/tools/perf'
$
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191126121253.28253-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And pick the shortest name: 'struct maps'.
The split existed because we used to have two groups of maps, one for
functions and one for variables, but that only complicated things,
sometimes we needed to figure out what was at some address and then had
to first try it on the functions group and if that failed, fall back to
the variables one.
That split is long gone, so for quite a while we had only one struct
maps per struct map_groups, simplify things by combining those structs.
First patch is the minimum needed to merge both, follow up patches will
rename 'thread->mg' to 'thread->maps', etc.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-hom6639ro7020o708trhxh59@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add to the "x86 instruction decoder - new instructions" test the following
instructions:
v4fmaddps
v4fmaddss
v4fnmaddps
v4fnmaddss
vaesdec
vaesdeclast
vaesenc
vaesenclast
vcvtne2ps2bf16
vcvtneps2bf16
vdpbf16ps
gf2p8affineinvqb
vgf2p8affineinvqb
gf2p8affineqb
vgf2p8affineqb
gf2p8mulb
vgf2p8mulb
vp2intersectd
vp2intersectq
vp4dpwssd
vp4dpwssds
vpclmulqdq
vpcompressb
vpcompressw
vpdpbusd
vpdpbusds
vpdpwssd
vpdpwssds
vpexpandb
vpexpandw
vpopcntb
vpopcntd
vpopcntq
vpopcntw
vpshldd
vpshldq
vpshldvd
vpshldvq
vpshldvw
vpshldw
vpshrdd
vpshrdq
vpshrdvd
vpshrdvq
vpshrdvw
vpshrdw
vpshufbitqmb
For information about the instructions, refer Intel SDM May 2019
(325462-070US) and Intel Architecture Instruction Set Extensions May
2019 (319433-037).
Committer testing:
$ perf test x86
61: x86 rdpmc : Ok
64: x86 instruction decoder - new instructions : Ok
66: x86 bp modify : Ok
$
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/20191125125044.31879-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
An error may be in place when tracepoint_error is called, use
parse_events__handle_error to avoid a memory leak and to capture the
first and last error. Error detected by LLVM's libFuzzer using the
following event:
$ perf stat -e 'msr/event/,f:e'
event syntax error: 'msr/event/,f:e'
\___ can't access trace events
Error: No permissions to read /sys/kernel/debug/tracing/events/f/e
Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing/'
Initial error:
event syntax error: 'msr/event/,f:e'
\___ no value assigned for term
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20191120180925.21787-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Default config for a PMU is defined before selected events are parsed.
That allows the user-entered config to override the default config.
However that does not allow for changing the default config based on
other options.
For example, if the user chooses AUX area sampling mode, in the case of
Intel PT, the psb_period needs to be small for sampling, so there is a
need to set the default psb_period to 0 (2 KiB) in that case. However
that should not override a value set by the user. To allow for that,
when using default config, record which bits of config were changed by
the user.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-13-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add functions to queue AUX area samples in advance
(auxtrace_queue_data()) or individually (auxtrace_queues__add_sample())
or find out what queue a sample belongs on
(auxtrace_queues__sample_queue()).
auxtrace_queue_data() can also queue snapshot data which keeps snapshots
and samples ordered with respect to each other in case support for that
is desired.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-12-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To allow individual events to be selected for AUX area sampling, add
aux-sample-size config term. attr.aux_sample_size is updated by
auxtrace_parse_sample_options() so that the existing validation will see
the value. Any event that has a non-zero aux_sample_size will cause AUX
area sampling to be configured, irrespective of the --aux-sample option.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-8-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support for parsing and validating AUX area sample options. At
present, the only option is the sample size, but it is also necessary to
ensure that events are in a group with an AUX area event as the leader.
Committer note:
Add missing 'static inline' in front of auxtrace_parse_sample_options()
for when we don't HAVE_AUXTRACE_SUPPORT.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Architectures are expected to know if AUX area sampling is supported by
the hardware. Add a function perf_can_aux_sample() which will determine
whether the kernel supports it.
Committer notes:
I reported that this message was taking place on a kernel without the
required bits:
# perf record --aux-sample -e '{intel_pt//u,branch-misses:u}'
Error:
The sys_perf_event_open() syscall returned with 7 (Argument list too long) for event (branch-misses:u).
/bin/dmesg | grep -i perf may provide additional information.
Adrian sent a patch addressing it, with this explanation:
----
perf_can_aux_sample_size() always returned true because it did not pass
the attribute size to sys_perf_event_open, nor correctly check the
return value and errno.
----
After applying it I get, later in the series, when --aux-sample is
added:
# perf record --aux-sample -e '{intel_pt//u,branch-misses:u}'
AUX area sampling is not supported by kernel
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>