Sample period calculation in deliver_sample_value is updated to
calculate the per-thread period delta for events that are inherit +
PERF_SAMPLE_READ. When the sampling event has this configuration, the
read_format.id is used with the tid from the sample to lookup the
storage of the previously accumulated counter total before calculating
the delta. All existing valid configurations where read_format.value
represents some global value continue to use just the read_format.id to
locate the storage of the previously accumulated total.
perf_sample_id is modified to support tracking per-thread
values, along with the existing global per-id values. In the
per-thread case, values are stored in a hash by tid within the
perf_sample_id, and are dynamically allocated as the number is not known
ahead of time.
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
Cc: james.clark@arm.com
Link: https://lore.kernel.org/r/20241001121505.1009685-2-ben.gainey@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
No event is printed in the "Branch Counter" column on hybrid machines.
For example,
$ perf record -e "{cpu_core/branch-instructions/pp,cpu_core/branches/}:S" -j any,counter
$ perf report --total-cycles
# Branch counter abbr list:
# cpu_core/branch-instructions/pp = A
# cpu_core/branches/ = B
# '-' No event occurs
# '+' Event occurrences may be lost due to branch counter saturated
#
# Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter
# ............... .............. ........... .......... ..............
44.54% 727.1K 0.00% 1 |+ |+ |
36.31% 592.7K 0.00% 2 |+ |+ |
17.83% 291.1K 0.00% 1 |+ |+ |
The branch counter information (br_cntr_width and br_cntr_nr) in the
perf_env is retrieved from the CPU_PMU_CAPS. However, the CPU_PMU_CAPS
is not available on hybrid machines. Without the width information, the
number of occurrences of an event cannot be calculated.
For a hybrid machine, the caps information should be retrieved from the
PMU_CAPS, and stored in the perf_env->pmu_caps.
Add a perf_env__find_br_cntr_info() to return the correct branch counter
information from the corresponding fields.
Committer notes:
While testing I couldn't s ee those "Branch counter" columns enabled by
pressing 'B' on the TUI, after reporting it to the list Kan explained
the situation:
<quote Kan Liang>
For a hybrid client, the "Branch Counter" feature is only supported
starting from the just released Lunar Lake. Perf falls back to only
"ANY" on your Raptor Lake.
The "The branch counter is not available" message is expected.
Here is the 'perf evlist' result from my Lunar Lake machine,
# perf evlist -v
cpu_core/branch-instructions/pp: type: 4 (cpu_core), size: 136, config: 0xc4 (branch-instructions), { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|READ|PERIOD|BRANCH_STACK|IDENTIFIER, read_format: ID|GROUP|LOST, disabled: 1, freq: 1, enable_on_exec: 1, precise_ip: 2, sample_id_all: 1, exclude_guest: 1, branch_sample_type: ANY|COUNTERS
#
</quote>
Fixes: 6f9d8d1de2 ("perf script: Add branch counters")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240909184201.553519-1-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Previously inject->is_pipe was set if the input or output were a
pipe. Determining the input was a pipe had to be done prior to
starting the session and opening the file. This was done by comparing
the input file name with '-' but it fails if the pipe file is written
to disk.
Opening a pipe file from disk will correctly set perf_data.is_pipe, but
this is too late for 'perf inject' and results in a broken file. A
workaround is 'cat pipe_perf|perf inject -i - ...'.
This change removes inject->is_pipe and changes the dependent
conditions to use the is_pipe flag on the input
(inject->session->data) and output files (inject->output). This
ensures the is_pipe condition reflects things like the header being
read.
The change removes the use of perf file header repiping, that is
writing the file header out while reading it in. The case of input
pipe and output file cannot repipe as the attributes for the file are
unknown. To resolve this, write the file header when writing to disk
and as the attributes may be unknown, write them after the data.
Update sessions repipe variable to be trace_event_repipe as those are
the only events now impacted by it. Update __perf_session__new as the
repipe_fd no longer needs passing. Fully removing repipe from session
header reading will be done in a later change.
Committer testing:
root@number:~# perf record -e syscalls:sys_enter_*sleep/max-stack=4/ -o - sleep 0.01 | perf report -i -
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.050 MB - ]
#
# Total Lost Samples: 0
#
# Samples: 1 of event 'syscalls:sys_enter_clock_nanosleep'
# Event count (approx.): 1
#
# Overhead Command Shared Object Symbol
# ........ ....... ............. ...............................
#
100.00% sleep libc.so.6 [.] clock_nanosleep@GLIBC_2.2.5
|
---__libc_start_main@@GLIBC_2.34
__libc_start_call_main
0x562fc2560a9f
clock_nanosleep@GLIBC_2.2.5
#
# (Tip: Create an archive with symtabs to analyse on other machine: perf archive)
#
root@number:~# perf record -e syscalls:sys_enter_*sleep/max-stack=4/ -o - sleep 0.01 > pipe.data
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.050 MB - ]
root@number:~# perf report --stdio -i pipe.data
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 1 of event 'syscalls:sys_enter_clock_nanosleep'
# Event count (approx.): 1
#
# Overhead Command Shared Object Symbol
# ........ ....... ............. ...............................
#
100.00% sleep libc.so.6 [.] clock_nanosleep@GLIBC_2.2.5
|
---__libc_start_main@@GLIBC_2.34
__libc_start_call_main
0x55f775975a9f
clock_nanosleep@GLIBC_2.2.5
#
# (Tip: To set sampling period of individual events use perf record -e cpu/cpu-cycles,period=100001/,cpu/branches,period=10001/ ...)
#
root@number:~#
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240829150154.37929-7-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In find_data_type(), it creates and deletes a debug info whenver it
tries to find data type for a sample. This is inefficient and it most
likely accesses the same binary again and again.
Let's add a single entry cache the debug info structure for the last DSO.
Depending on sample data, it usually gives me 2~3x (and sometimes more)
speed ups.
Note that this will introduce a little difference in the output due to
the order of checking stack operations. It used to check the stack ops
before checking the availability of debug info but I moved it after the
symbol check. So it'll report stack operations in DSOs without debug
info as unknown. But I think it's ok and better to have the checking
near the caching logic.
Committer testing:
root@x1:~# perf mem record -a sleep 5s
root@x1:~# perf evlist
cpu_atom/mem-loads,ldlat=30/P
cpu_atom/mem-stores/P
dummy:u
root@x1:~# diff -u before after
--- before 2024-08-08 09:33:53.880780784 -0300
+++ after 2024-08-08 09:35:13.917325041 -0300
@@ -81,8 +81,8 @@
# Overhead Data Type
# ........ .........
#
- 55.43% (unknown)
- 11.61% (stack operation)
+ 55.56% (unknown)
+ 11.48% (stack operation)
4.93% struct pcpu_hot
3.26% unsigned int
2.48% struct
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240805234648.1453689-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's possible to save pipe output of perf record into a file.
$ perf record -o- ... > pipe.data
And you can use the data same as the normal perf data.
$ perf report -i pipe.data
In that case, perf tools will treat the input as a pipe, but it can get
the total size of the input. This means it can show the progress bar
unlike the normal pipe input (which doesn't know the total size in
advance).
While at it, fix the string in __perf_session__process_dir_events().
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240627181916.1202110-1-namhyung@kernel.org
Add a new branch filter, "counter", for the branch counter option. It is
used to mark the events which should be logged in the branch. If it is
applied with the -j option, the counters of all the events should be
logged in the branch. If the legacy kernel doesn't support the new
branch sample type, switching off the branch counter filter.
The stored counter values in each branch are displayed right after the
regular branch stack information via perf report -D.
Usage examples:
# perf record -e "{branch-instructions,branch-misses}:S" -j any,counter
Only the first event, branch-instructions, collect the LBR. Both
branch-instructions and branch-misses are marked as logged events. The
occurrences information of them can be found in the branch stack
extension space of each branch.
# perf record -e "{cpu/branch-instructions,branch_type=any/,cpu/branch-misses,branch_type=counter/}"
Only the first event, branch-instructions, collect the LBR. Only the
branch-misses event is marked as a logged event.
Committer notes:
I noticed 'perf test "Sample parsing"' failing, reported to the list and
Kan provided a patch that checks if the evsel has a leader and that
evsel->evlist is set, the comment in the source code further explains
it.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
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: Tinghao Zhang <tinghao.zhang@intel.com>
Link: https://lore.kernel.org/r/20231025201626.3000228-8-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Remove the LIBTRACEEVENT_DYNAMIC and LIBTRACEFS_DYNAMIC make command
line variables.
If libtraceevent isn't installed or NO_LIBTRACEEVENT=1 is passed to the
build, don't compile in libtraceevent and libtracefs support.
This also disables CONFIG_TRACE that controls "perf trace".
CONFIG_LIBTRACEEVENT is used to control enablement in Build/Makefiles,
HAVE_LIBTRACEEVENT is used in C code.
Without HAVE_LIBTRACEEVENT tracepoints are disabled and as such the
commands kmem, kwork, lock, sched and timechart are removed. The
majority of commands continue to work including "perf test".
Committer notes:
Fixed up a tools/perf/util/Build reject and added:
#include <traceevent/event-parse.h>
to tools/perf/util/scripting-engines/trace-event-perl.c.
Committer testing:
$ rpm -qi libtraceevent-devel
Name : libtraceevent-devel
Version : 1.5.3
Release : 2.fc36
Architecture: x86_64
Install Date: Mon 25 Jul 2022 03:20:19 PM -03
Group : Unspecified
Size : 27728
License : LGPLv2+ and GPLv2+
Signature : RSA/SHA256, Fri 15 Apr 2022 02:11:58 PM -03, Key ID 999f7cbf38ab71f4
Source RPM : libtraceevent-1.5.3-2.fc36.src.rpm
Build Date : Fri 15 Apr 2022 10:57:01 AM -03
Build Host : buildvm-x86-05.iad2.fedoraproject.org
Packager : Fedora Project
Vendor : Fedora Project
URL : https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/
Bug URL : https://bugz.fedoraproject.org/libtraceevent
Summary : Development headers of libtraceevent
Description :
Development headers of libtraceevent-libs
$
Default build:
$ ldd ~/bin/perf | grep tracee
libtraceevent.so.1 => /lib64/libtraceevent.so.1 (0x00007f1dcaf8f000)
$
# perf trace -e sched:* --max-events 10
0.000 migration/0/17 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, dest_cpu: 1)
0.005 migration/0/17 sched:sched_wake_idle_without_ipi(cpu: 1)
0.011 migration/0/17 sched:sched_switch(prev_comm: "", prev_pid: 17 (migration/0), prev_state: 1, next_comm: "", next_prio: 120)
1.173 :0/0 sched:sched_wakeup(comm: "", pid: 3138 (gnome-terminal-), prio: 120)
1.180 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 3138 (gnome-terminal-), next_prio: 120)
0.156 migration/1/21 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, orig_cpu: 1, dest_cpu: 2)
0.160 migration/1/21 sched:sched_wake_idle_without_ipi(cpu: 2)
0.166 migration/1/21 sched:sched_switch(prev_comm: "", prev_pid: 21 (migration/1), prev_state: 1, next_comm: "", next_prio: 120)
1.183 :0/0 sched:sched_wakeup(comm: "", pid: 1602985 (kworker/u16:0-f), prio: 120, target_cpu: 1)
1.186 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 1602985 (kworker/u16:0-f), next_prio: 120)
#
Had to tweak tools/perf/util/setup.py to make sure the python binding
shared object links with libtraceevent if -DHAVE_LIBTRACEEVENT is
present in CFLAGS.
Building with NO_LIBTRACEEVENT=1 uncovered some more build failures:
- Make building of data-convert-bt.c to CONFIG_LIBTRACEEVENT=y
- perf-$(CONFIG_LIBTRACEEVENT) += scripts/
- bpf_kwork.o needs also to be dependent on CONFIG_LIBTRACEEVENT=y
- The python binding needed some fixups and util/trace-event.c can't be
built and linked with the python binding shared object, so remove it
in tools/perf/util/setup.py and exclude it from the list of
dependencies in the python/perf.so Makefile.perf target.
Building without libtraceevent-devel installed uncovered more build
failures:
- The python binding tools/perf/util/python.c was assuming that
traceevent/parse-events.h was always available, which was the case
when we defaulted to using the in-kernel tools/lib/traceevent/ files,
now we need to enclose it under ifdef HAVE_LIBTRACEEVENT, just like
the other parts of it that deal with tracepoints.
- We have to ifdef the rules in the Build files with
CONFIG_LIBTRACEEVENT=y to build builtin-trace.c and
tools/perf/trace/beauty/ as we only ifdef setting CONFIG_TRACE=y when
setting NO_LIBTRACEEVENT=1 in the make command line, not when we don't
detect libtraceevent-devel installed in the system. Simplification here
to avoid these two ways of disabling builtin-trace.c and not having
CONFIG_TRACE=y when libtraceevent-devel isn't installed is the clean
way.
From Athira:
<quote>
tools/perf/arch/powerpc/util/Build
-perf-y += kvm-stat.o
+perf-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o
</quote>
Then, ditto for arm64 and s390, detected by container cross build tests.
- s/390 uses test__checkevent_tracepoint() that is now only available if
HAVE_LIBTRACEEVENT is defined, enclose the callsite with ifder HAVE_LIBTRACEEVENT.
Also from Athira:
<quote>
With this change, I could successfully compile in these environment:
- Without libtraceevent-devel installed
- With libtraceevent-devel installed
- With “make NO_LIBTRACEEVENT=1”
</quote>
Then, finally rename CONFIG_TRACEEVENT to CONFIG_LIBTRACEEVENT for
consistency with other libraries detected in tools/perf/.
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20221205225940.3079667-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This updates the perf tool with generic branch type classification with new
ABI extender place holder i.e PERF_BR_EXTEND_ABI, the new 4 bit branch type
field i.e perf_branch_entry.new_type, new generic page fault related branch
types and some arch specific branch types as added earlier in the kernel.
Committer note:
Add an extra entry to the branch_type_name array to cope with
PERF_BR_EXTEND_ABI, to address build warnings on some compiler/systems,
like:
75 8.89 ubuntu:20.04-x-powerpc64el : FAIL gcc version 10.3.0 (Ubuntu 10.3.0-1ubuntu1~20.04)
inlined from 'branch_type_stat_display' at util/branch.c:152:4:
/usr/powerpc64le-linux-gnu/include/bits/stdio2.h:100:10: error: '%8s' directive argument is null [-Werror=format-overflow=]
100 | return __fprintf_chk (__stream, __USE_FORTIFY_LEVEL - 1, __fmt,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
101 | __va_arg_pack ());
| ~~~~~~~~~~~~~~~~~
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20220824044822.70230-7-anshuman.khandual@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The recent kernel added lost count can be read from either read(2) or
ring buffer data with PERF_SAMPLE_READ. As it's a variable length data
we need to access it according to the format info.
But for perf tools use cases, PERF_FORMAT_ID is always set. So we can
only check PERF_FORMAT_LOST bit to determine the data format.
Add sample_read_value_size() and next_sample_read_value() helpers to
make it a bit easier to access. Use them in all places where it reads
the struct sample_read_value.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220819003644.508916-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A mask encoding of a cpu map is laid out as:
u16 nr
u16 long_size
unsigned long mask[];
However, the mask may be 8-byte aligned meaning there is a 4-byte pad
after long_size. This means 32-bit and 64-bit builds see the mask as
being at different offsets. On top of this the structure is in the byte
data[] encoded as:
u16 type
char data[]
This means the mask's struct isn't the required 4 or 8 byte aligned, but
is offset by 2. Consequently the long reads and writes are causing
undefined behavior as the alignment is broken.
Fix the mask struct by creating explicit 32 and 64-bit variants, use a
union to avoid data[] and casts; the struct must be packed so the
layout matches the existing perf.data layout. Taking an address of a
member of a packed struct breaks alignment so pass the packed
perf_record_cpu_map_data to functions, so they can access variables with
the right alignment.
As the 64-bit version has 4 bytes of padding, optimizing writing to only
write the 32-bit version.
Committer notes:
Disable warnings about 'packed' that break the build in some arches like
riscv64, but just around that specific struct.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Colin Ian King <colin.king@intel.com>
Cc: Dave Marchevsky <davemarchevsky@fb.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Kees Kook <keescook@chromium.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20220614143353.1559597-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When injecting events from a guest perf.data file, the events will have
separate sample ID numbers. These ID numbers can then be used to determine
which machine an event belongs to. To facilitate that, add machine_pid and
vcpu to id_index records. For backward compatibility, these are added at
the end of the record, and the length of the record is used to determine
if they are present or not.
Note, this is needed because the events from a guest perf.data file contain
the pid/tid of the process running at that time inside the VM not the
pid/tid of the (QEMU) hypervisor thread. So a way is needed to relate
guest events back to the guest machine and VCPU, and using sample ID
numbers for that is relatively simple and convenient.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220711093218.10967-11-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In preparation for recording sideband events in a virtual machine guest so
that they can be injected into a host perf.data file.
This is needed to enable injecting events after the initial synthesized
user events (that have an all zero id sample) but before regular events.
Committer notes:
Add entry about PERF_RECORD_FINISHED_INIT to
tools/perf/Documentation/perf.data-file-format.txt.
Committer testing:
Before:
# perf report -D | grep FINISHED
0 0x5910 [0x8]: PERF_RECORD_FINISHED_ROUND
FINISHED_ROUND events: 1 ( 0.5%)
#
After:
# perf record -- sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.020 MB perf.data (7 samples) ]
# perf report -D | grep FINISHED
0 0x5068 [0x8]: PERF_RECORD_FINISHED_INIT: unhandled!
0 0x5390 [0x8]: PERF_RECORD_FINISHED_ROUND
FINISHED_ROUND events: 1 ( 0.5%)
FINISHED_INIT events: 1 ( 0.5%)
#
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220610113316.6682-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A common case for KVM test programs is that the test program acts as the
hypervisor, creating, running and destroying the virtual machine, and
providing the guest object code from its own object code. In this case,
the VM is not running an OS, but only the functions loaded into it by the
hypervisor test program, and conveniently, loaded at the same virtual
addresses.
Normally to resolve addresses, MMAP events are needed to map addresses
back to the object code and debug symbols for that object code.
Currently, there is no way to get such mapping information from guests
but, in the scenario described above, the guest has the same mappings
as the hypervisor, so support for that scenario can be achieved.
To support that, copy the host thread's maps to the guest thread's maps.
Note, we do not discover the guest until we encounter a guest event,
which works well because it is not until then that we know that the host
thread's maps have been set up.
Typically the main function for the guest object code is called
"guest_code", hence the name chosen for this feature. Note, that is just a
convention, the function could be named anything, and the tools do not
care.
This is primarily aimed at supporting Intel PT, or similar, where trace
data can be recorded for a guest. Refer to the final patch in this series
"perf intel-pt: Add guest_code support" for an example.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220517131011.6117-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This can help with debugging issues. It only prints when -j save_type
is used otherwise an empty string is printed.
Before the change:
101603801707130 0xa70 [0x630]: PERF_RECORD_SAMPLE(IP, 0x2): 1108/1108: 0xffff9c1df24c period: 10694 addr: 0
... branch stack: nr:64
..... 0: 0000ffff9c26029c -> 0000ffff9c26f340 0 cycles P 0
..... 1: 0000ffff9c2601bc -> 0000ffff9c26f340 0 cycles P 0
After the change:
101603801707130 0xa70 [0x630]: PERF_RECORD_SAMPLE(IP, 0x2): 1108/1108: 0xffff9c1df24c period: 10694 addr: 0
... branch stack: nr:64
..... 0: 0000ffff9c26029c -> 0000ffff9c26f340 0 cycles P 0 CALL
..... 1: 0000ffff9c2601bc -> 0000ffff9c26f340 0 cycles P 0 IND_CALL
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220307171917.2555829-3-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
