commit c79ee2b2160909889df67c8801352d3e69d43a1a upstream.
An overflow (OVF packet) is treated as an error because it represents a
loss of trace data, but there is no loss of synchronization, so the packet
state should be INTEL_PT_STATE_IN_SYNC not INTEL_PT_STATE_ERR_RESYNC.
To support that, some additional variables must be reset, and the FUP
packet that may follow OVF is treated as an FUP event.
Fixes: f4aa081949 ("perf tools: Add Intel PT decoder")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
[Adrian: Backport to v5.10]
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ad106a26aef3a95ac7ca88d033b431661ba346ce upstream.
When syncing, it may be that branch packet generation is not enabled at
that point, in which case there will not immediately be a control-flow
packet, so some packets before a control flow packet turns up, get
ignored. However, the decoder is in sync as soon as a PSB is found, so
the state should be set accordingly.
Fixes: f4aa081949 ("perf tools: Add Intel PT decoder")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v5.15+
Link: https://lore.kernel.org/r/20211210162303.2288710-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
[Adrian: Backport to v5.10]
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A single q option decodes ip from only FUP/TIP packets. Make it so that
repeating the q option (i.e. qq) decodes only PSB+, getting ip if there
is a FUP packet within PSB+ (i.e. between PSB and PSBEND).
Example:
$ perf record -e intel_pt//u grep -rI pudding drivers
[ perf record: Woken up 52 times to write data ]
[ perf record: Captured and wrote 57.870 MB perf.data ]
$ time perf script --itrace=bi | wc -l
58948289
real 1m23.863s
user 1m23.251s
sys 0m7.452s
$ time perf script --itrace=biq | wc -l
3385694
real 0m4.453s
user 0m4.455s
sys 0m0.328s
$ time perf script --itrace=biqq | wc -l
1883
real 0m0.047s
user 0m0.043s
sys 0m0.009s
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200710151104.15137-13-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use the new itrace 'q' option to add support for a mode of decoding that
ignores TNT, does not walk object code, but gets the ip from FUP and TIP
packets.
Example:
$ perf record -e intel_pt//u grep -rI pudding drivers
[ perf record: Woken up 52 times to write data ]
[ perf record: Captured and wrote 57.870 MB perf.data ]
$ time perf script --itrace=bi | wc -l
58948289
real 1m23.863s
user 1m23.251s
sys 0m7.452s
$ time perf script --itrace=biq | wc -l
3385694
real 0m4.453s
user 0m4.455s
sys 0m0.328s
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200710151104.15137-12-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now that there's a common version of the decoder for all tools, use it
instead of the local copy.
Also use perf's check-headers.sh script to diff the decoder files to
make sure they remain in sync with the kernel version. Objtool has a
similar check.
Committer notes:
Had to keep this all pointing explicitely to x86 headers/files, i.e.
instead of asm/isnn.h we had to use ../include/asm/insn.h when the files
were in differemt dirs, or just replace "<asm/foo.h>" with "foo.h".
This way we continue to be able to process perf.data files with Intel PT
traces in distros other than x86.
Also fixed up the awk script paths to use $(srcdir)/tools/arch instead
or relative directories so that we keep detached tarballs (make help |
grep perf) working.
For now the include lines in these headers are being ignored so as not
to flag false reports of kernel/tools out of sync.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: x86@kernel.org
Link: http://lore.kernel.org/lkml/8a37e615d2880f039505d693d1e068a009358a2b.1567118001.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The core-to-bus ratio (CBR) provides the CPU frequency. With branches
enabled, the decoder was outputting CBR changes only when there was a
branch. That loses the correct time of the change if the trace is not in
context (e.g. not tracing kernel space). Change to output the CBR change
immediately.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190622093248.581-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add 3 new packets to supports PEBS via PT, namely Block Begin Packet
(BBP), Block Item Packet (BIP) and Block End Packet (BEP). PEBS data is
encoded into multiple BIP packets that come between BBP and BEP. The BEP
packet might be associated with a FUP packet. That is indicated by using
a separate packet type (INTEL_PT_BEP_IP) similar to other packets types
with the _IP suffix.
Refer to the Intel SDM for more information about PEBS via PT:
https://software.intel.com/en-us/articles/intel-sdm
May 2019 version: Vol. 3B 18.5.5.2 PEBS output to Intel® Processor Trace
Decoding of BIP packets conflicts with single-byte TNT packets. Since
BIP packets only occur in the context of a block (i.e. between BBP and
BEP), that context must be recorded and passed to the packet decoder.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190610072803.10456-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
perf record:
Alexey Budankov:
- Allow mixing --user-regs with --call-graph=dwarf, making sure that
the minimal set of registers for DWARF unwinding is present in the
set of user registers requested to be present in each sample, while
warning the user that this may make callchains unreliable if more
that the minimal set of registers is needed to unwind.
yuzhoujian:
- Add support to collect callchains from kernel or user space only,
IOW allow setting the perf_event_attr.exclude_callchain_{kernel,user}
bits from the command line.
perf trace:
Arnaldo Carvalho de Melo:
- Remove x86_64 specific syscall numbers from the augmented_raw_syscalls
BPF in-kernel collector of augmented raw_syscalls:sys_{enter,exit}
payloads, use instead the syscall numbers obtainer either by the
arch specific syscalltbl generators or from audit-libs.
- Allow 'perf trace' to ask for the number of bytes to collect for
string arguments, for now ask for PATH_MAX, i.e. the whole
pathnames, which ends up being just a way to speficy which syscall
args are pathnames and thus should be read using bpf_probe_read_str().
- Skip unknown syscalls when expanding strace like syscall groups.
This helps using the 'string' group of syscalls to work in arm64,
where some of the syscalls present in x86_64 that deal with
strings, for instance 'access', are deprecated and this should not
be asked for tracing.
Leo Yan:
- Exit when failing to build eBPF program.
perf config:
Arnaldo Carvalho de Melo:
- Bail out when a handler returns failure for a key-value pair. This
helps with cases where processing a key-value pair is not just a
matter of setting some tool specific knob, involving, for instance
building a BPF program to then attach to the list of events 'perf
trace' will use, e.g. augmented_raw_syscalls.c.
perf.data:
Kan Liang:
- Read and store die ID information available in new Intel processors
in CPUID.1F in the CPU topology written in the perf.data header.
perf stat:
Kan Liang:
- Support per-die aggregation.
Documentation:
Arnaldo Carvalho de Melo:
- Update perf.data documentation about the CPU_TOPOLOGY, MEM_TOPOLOGY,
CLOCKID and DIR_FORMAT headers.
Song Liu:
- Add description of headers HEADER_BPF_PROG_INFO and HEADER_BPF_BTF.
Leo Yan:
- Update default value for llvm.clang-bpf-cmd-template in 'man perf-config'.
JVMTI:
Jiri Olsa:
- Address gcc string overflow warning for strncpy()
core:
- Remove superfluous nthreads system_wide setup in perf_evsel__alloc_fd().
Intel PT:
Adrian Hunter:
- Add support for samples to contain IPC ratio, collecting cycles
information from CYC packets, showing the IPC info periodically, because
Intel PT does not update the cycle count on every branch or instruction,
the incremental values will often be zero. When there are values, they
will be the number of instructions and number of cycles since the last
update, and thus represent the average IPC since the last IPC value.
E.g.:
# perf record --cpu 1 -m200000 -a -e intel_pt/cyc/u sleep 0.0001
rounding mmap pages size to 1024M (262144 pages)
[ perf record: Woken up 0 times to write data ]
[ perf record: Captured and wrote 2.208 MB perf.data ]
# perf script --insn-trace --xed -F+ipc,-dso,-cpu,-tid
#
<SNIP + add line numbering to make sense of IPC counts e.g.: (18/3)>
1 cc1 63501.650479626: 7f5219ac27bf _int_free+0x3f jnz 0x7f5219ac2af0 IPC: 0.81 (36/44)
2 cc1 63501.650479626: 7f5219ac27c5 _int_free+0x45 cmp $0x1f, %rbp
3 cc1 63501.650479626: 7f5219ac27c9 _int_free+0x49 jbe 0x7f5219ac2b00
4 cc1 63501.650479626: 7f5219ac27cf _int_free+0x4f test $0x8, %al
5 cc1 63501.650479626: 7f5219ac27d1 _int_free+0x51 jnz 0x7f5219ac2b00
6 cc1 63501.650479626: 7f5219ac27d7 _int_free+0x57 movq 0x13c58a(%rip), %rcx
7 cc1 63501.650479626: 7f5219ac27de _int_free+0x5e mov %rdi, %r12
8 cc1 63501.650479626: 7f5219ac27e1 _int_free+0x61 movq %fs:(%rcx), %rax
9 cc1 63501.650479626: 7f5219ac27e5 _int_free+0x65 test %rax, %rax
10 cc1 63501.650479626: 7f5219ac27e8 _int_free+0x68 jz 0x7f5219ac2821
11 cc1 63501.650479626: 7f5219ac27ea _int_free+0x6a leaq -0x11(%rbp), %rdi
12 cc1 63501.650479626: 7f5219ac27ee _int_free+0x6e mov %rdi, %rsi
13 cc1 63501.650479626: 7f5219ac27f1 _int_free+0x71 shr $0x4, %rsi
14 cc1 63501.650479626: 7f5219ac27f5 _int_free+0x75 cmpq %rsi, 0x13caf4(%rip)
15 cc1 63501.650479626: 7f5219ac27fc _int_free+0x7c jbe 0x7f5219ac2821
16 cc1 63501.650479626: 7f5219ac2821 _int_free+0xa1 cmpq 0x13f138(%rip), %rbp
17 cc1 63501.650479626: 7f5219ac2828 _int_free+0xa8 jnbe 0x7f5219ac28d8
18 cc1 63501.650479626: 7f5219ac28d8 _int_free+0x158 testb $0x2, 0x8(%rbx)
19 cc1 63501.650479628: 7f5219ac28dc _int_free+0x15c jnz 0x7f5219ac2ab0 IPC: 6.00 (18/3)
<SNIP>
- Allow using time ranges with Intel PT, i.e. these features, already
present but not optimially usable with Intel PT, should be now:
Select the second 10% time slice:
$ perf script --time 10%/2
Select from 0% to 10% time slice:
$ perf script --time 0%-10%
Select the first and second 10% time slices:
$ perf script --time 10%/1,10%/2
Select from 0% to 10% and 30% to 40% slices:
$ perf script --time 0%-10%,30%-40%
cs-etm (ARM):
Mathieu Poirier:
- Add support for CPU-wide trace scenarios.
s390:
Thomas Richter:
- Fix missing kvm module load for s390.
- Fix OOM error in TUI mode on s390
- Support s390 diag event display when doing analysis on !s390
architectures.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Intel PT decoding is done in time order. In order to support efficient time
interval filtering, add a facility to "fast forward" towards a particular
timestamp. That involves finding the right buffer, stepping to that buffer,
and then stepping forward PSBs. Because decoding must begin at a PSB,
"fast forward" stops at the last PSB that has a timestamp before the target
timestamp.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190604130017.31207-9-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation this program
is distributed in the hope it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 263 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When CYC packets are not available, it is still possible to count cycles
using TSC/TMA/MTC timestamps.
As the timestamp increments in TSC ticks, convert to CPU cycles using
the current core-to-bus ratio.
Do not accumulate cycles when control flow packet generation is not
enabled, nor when time has been "lost", typically due to mwait, which is
indicated by a TSC/TMA packet that is not part of PSB+.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190520113728.14389-12-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In preparation for providing instructions-per-cycle (IPC) information,
accumulate cycle count from CYC packets.
Although CYC packets are optional (requires config term 'cyc' to enable
cycle-accurate mode when recording), the simplest way to count cycles is
with CYC packets.
The first complication is that cycles must be counted only when also
counting instructions.
That means when control flow packet generation is enabled i.e. between
TIP.PGE and TIP.PGD packets.
Also, sampling the cycle count follows the same rules as sampling the
timestamp, that is, not before the instruction to which the decoder is
walking is reached.
In addition, the cycle count is not accurate for any but the first
branch of a TNT packet.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190520113728.14389-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1334 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The sample timestamp is updated to ensure that the timestamp represents
the time of the sample and not a branch that the decoder is still
walking towards. The sample timestamp is updated when the decoder
returns, but the decoder does not return for non-taken branches. Update
the sample timestamp then also.
Note that commit 3f04d98e97 ("perf intel-pt: Improve sample
timestamp") was also a stable fix and appears, for example, in v4.4
stable tree as commit a4ebb58fd124 ("perf intel-pt: Improve sample
timestamp").
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: 3f04d98e97 ("perf intel-pt: Improve sample timestamp")
Link: http://lkml.kernel.org/r/20190510124143.27054-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The decoder uses its current timestamp in samples. Usually that is a
timestamp that has already passed, but in some cases it is a timestamp
for a branch that the decoder is walking towards, and consequently
hasn't reached.
The intel_pt_sample_time() function decides which is which, but was not
handling TNT packets exactly correctly.
In the case of TNT, the timestamp applies to the first branch, so the
decoder must first walk to that branch.
That means intel_pt_sample_time() should return true for TNT, and this
patch makes that change. However, if the first branch is a non-taken
branch (i.e. a 'N'), then intel_pt_sample_time() needs to return false
for subsequent taken branches in the same TNT packet.
To handle that, introduce a new state INTEL_PT_STATE_TNT_CONT to
distinguish the cases.
Note that commit 3f04d98e97 ("perf intel-pt: Improve sample
timestamp") was also a stable fix and appears, for example, in v4.4
stable tree as commit a4ebb58fd124 ("perf intel-pt: Improve sample
timestamp").
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: 3f04d98e97 ("perf intel-pt: Improve sample timestamp")
Link: http://lkml.kernel.org/r/20190510124143.27054-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The timestamp used to determine if an instruction sample is made, is an
estimate based on the number of instructions since the last known
timestamp. A consequence is that it might go backwards, which results in
extra samples. Change it so that a sample is only made when the
timestamp goes forwards.
Note this does not affect a sampling period of 0 or sampling periods
specified as a count of instructions.
Example:
Before:
$ perf script --itrace=i10us
ls 13812 [003] 2167315.222583: 3270 instructions:u: 7fac71e2e494 __GI___tunables_init+0xf4 (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 30902 instructions:u: 7fac71e2da0f _dl_cache_libcmp+0x2f (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 10 instructions:u: 7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 8 instructions:u: 7fac71e2d9ea _dl_cache_libcmp+0xa (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 14 instructions:u: 7fac71e2d9ea _dl_cache_libcmp+0xa (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 6 instructions:u: 7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 14 instructions:u: 7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 4 instructions:u: 7fac71e2dab2 _dl_cache_libcmp+0xd2 (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222728: 16423 instructions:u: 7fac71e2477a _dl_map_object_deps+0x1ba (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222734: 12731 instructions:u: 7fac71e27938 _dl_name_match_p+0x68 (/lib/x86_64-linux-gnu/ld-2.28.so)
...
After:
$ perf script --itrace=i10us
ls 13812 [003] 2167315.222583: 3270 instructions:u: 7fac71e2e494 __GI___tunables_init+0xf4 (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222667: 30902 instructions:u: 7fac71e2da0f _dl_cache_libcmp+0x2f (/lib/x86_64-linux-gnu/ld-2.28.so)
ls 13812 [003] 2167315.222728: 16479 instructions:u: 7fac71e2477a _dl_map_object_deps+0x1ba (/lib/x86_64-linux-gnu/ld-2.28.so)
...
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Fixes: f4aa081949 ("perf tools: Add Intel PT decoder")
Link: http://lkml.kernel.org/r/20190510124143.27054-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is a fix for another instance of the skid problem Milian recently
found [1]
The LBRs don't freeze at the exact same time as the PMI is triggered.
The perf script brstackinsn code that dumps LBR assembler assumes that
the last branch in the LBR leads to the sample point. But with skid
it's possible that the CPU executes one or more branches before the
sample, but which do not appear in the LBR.
What happens then is either that the sample point is before the last LBR
branch. In this case the dumper sees a negative length and ignores it.
Or it the sample point is long after the last branch. Then the dumper
sees a very long block and dumps it upto its block limit (16k bytes),
which is noise in the output.
On typical sample session this can happen regularly.
This patch tries to detect and handle the situation. On the last block
that is dumped by the LBR dumper we always stop on the first branch. If
the block length is negative just scan forward to the first branch.
Otherwise scan until a branch is found.
The PT decoder already has a function that uses the instruction decoder
to detect branches, so we can just reuse it here.
Then when a terminating branch is found print an indication and stop
dumping. This might miss a few instructions, but at least shows no
runaway blocks.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Link: http://lkml.kernel.org/r/20181120050617.4119-1-andi@firstfloor.org
[ Resolved conflict with dd2e18e9ac ("perf tools: Support 'srccode' output") ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
