In systems having higher node numbers available like node
255, perf numa bench will fail with SIGABORT.
<<>>
perf: bench/numa.c:1416: init: Assertion `!(g->p.nr_nodes > 64 || g->p.nr_nodes < 0)' failed.
Aborted (core dumped)
<<>>
Snippet from 'numactl -H' below on a powerpc system where the highest
node number available is 255:
available: 6 nodes (0,8,252-255)
node 0 cpus: <cpu-list>
node 0 size: 519587 MB
node 0 free: 516659 MB
node 8 cpus: <cpu-list>
node 8 size: 523607 MB
node 8 free: 486757 MB
node 252 cpus:
node 252 size: 0 MB
node 252 free: 0 MB
node 253 cpus:
node 253 size: 0 MB
node 253 free: 0 MB
node 254 cpus:
node 254 size: 0 MB
node 254 free: 0 MB
node 255 cpus:
node 255 size: 0 MB
node 255 free: 0 MB
node distances:
node 0 8 252 253 254 255
Note: <cpu-list> expands to actual cpu list in the original output.
These nodes 252-255 are to represent the memory on GPUs and are valid
nodes.
The perf numa bench init code has a condition check to see if the number
of NUMA nodes (nr_nodes) exceeds MAX_NR_NODES. The value of MAX_NR_NODES
defined in perf code is 64. And the 'nr_nodes' is the value from
numa_max_node() which represents the highest node number available in the
system. In some systems where we could have NUMA node 255, this condition
check fails and results in SIGABORT.
The numa benchmark uses static value of MAX_NR_NODES in the code to
represent size of two NUMA node arrays and node bitmask used for setting
memory policy. Patch adds a fix to dynamically allocate size for the
two arrays and bitmask value based on the node numbers available in the
system. With the fix, perf numa benchmark will work with node configuration
on any system and thus removes the static MAX_NR_NODES value.
Signed-off-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/1614271802-1503-1-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
__cmd_diff() sets result of perf_session__new() to d->session.
In case of failure, it's errno and perf-diff may crash with:
failed to open perf.data: Permission denied
Failed to open perf.data
Segmentation fault (core dumped)
From the coredump:
0 0x00005569a62b5955 in auxtrace__free (session=0xffffffffffffffff)
at util/auxtrace.c:2681
1 0x00005569a626b37d in perf_session__delete (session=0xffffffffffffffff)
at util/session.c:295
2 perf_session__delete (session=0xffffffffffffffff) at util/session.c:291
3 0x00005569a618008a in __cmd_diff () at builtin-diff.c:1239
4 cmd_diff (argc=<optimized out>, argv=<optimized out>) at builtin-diff.c:2011
[..]
Funny enough, it won't always crash. For me it crashes only if failed
file is second in cmd-line: the reason is that cmd_diff() check files for
branch-stacks [in check_file_brstack()] and if the first file doesn't
have brstacks, it doesn't proceed to try open other files from cmd-line.
Check d->session before calling perf_session__delete().
Another solution would be assigning to temporary variable, checking it,
but I find it easier to follow with IS_ERR() check in the same function.
After some time it's still obvious why the check is needed, and with
temp variable it's possible to make the same mistake.
Committer testing:
$ perf record sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
$ perf diff
failed to open perf.data.old: No such file or directory
Failed to open perf.data.old
$ perf record sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
$ perf diff
# Event 'cycles:u'
#
# Baseline Delta Abs Shared Object Symbol
# ........ ......... ................ ..........................
#
0.92% +87.66% [unknown] [k] 0xffffffff8825de16
11.39% +0.04% ld-2.32.so [.] __GI___tunables_init
87.70% ld-2.32.so [.] _dl_check_map_versions
$ sudo chown root:root perf.data
[sudo] password for acme:
$ perf diff
failed to open perf.data: Permission denied
Failed to open perf.data
Segmentation fault (core dumped)
$
After the patch:
$ perf diff
failed to open perf.data: Permission denied
Failed to open perf.data
$
Signed-off-by: Dmitry Safonov <dima@arista.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dmitry safonov <dima@arista.com>
Link: http://lore.kernel.org/lkml/20210302023533.1572231-1-dima@arista.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo reported issue for following build command:
$ rm -rf /tmp/krava; mkdir /tmp/krava; make O=/tmp/krava clean
CLEAN config
/bin/sh: line 0: cd: /tmp/krava/feature/: No such file or directory
../../scripts/Makefile.include:17: *** output directory "/tmp/krava/feature/" does not exist. Stop.
make[1]: *** [Makefile.perf:1010: config-clean] Error 2
make: *** [Makefile:90: clean] Error 2
The problem is that now that we include scripts/Makefile.include
in feature's Makefile (which is fine and needed), we need to ensure
the OUTPUT directory exists, before executing (out of tree) clean
command.
Removing the feature's cleanup from perf Makefile and fixing
feature's cleanup under build Makefile, so it now checks that
there's existing OUTPUT directory before calling the clean.
Fixes: 211a741cd3 ("tools: Factor Clang, LLC and LLVM utils definitions")
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13-git
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210224150831.409639-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To get the changes in:
fbcee2ebe8 ("powerpc/32: Always save non volatile GPRs at syscall entry")
That shouldn't cause any change in tooling, just silences the following
tools/perf/ build warning:
Warning: Kernel ABI header at 'tools/perf/arch/powerpc/entry/syscalls/syscall.tbl' differs from latest version at 'arch/powerpc/kernel/syscalls/syscall.tbl'
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Right now, when Line numbers are displayed, one can't easily find a
source file that the line corresponds to.
When a source line is selected and 'l' is pressed, full source file
location is displayed in perf UI footer line. The hotkey works only for
source code lines.
Signed-off-by: Martin Liška <mliska@suse.cz>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lore.kernel.org/lkml/25a6384f-d862-5dda-4fec-8f0555599c75@suse.cz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Warning "dso not found" is reported when using "perf report -D".
66702781413407 0x32c0 [0x30]: PERF_RECORD_SAMPLE(IP, 0x2): 28177/28177: 0x55e493e00563 period: 106578 addr: 0
... thread: perf:28177
...... dso: <not found>
66702727832429 0x9dd8 [0x38]: PERF_RECORD_COMM exec: triad_loop:28177/28177
The PERF_RECORD_SAMPLE event (timestamp: 66702781413407) should be after the
PERF_RECORD_COMM event (timestamp: 66702727832429), but it's early processed.
So for most of cases, it makes sense to keep the event ordered even for dump
mode. But it would be also useful to disable ordered_events for reporting raw
dump to see events as they are stored in the perf.data file.
So now, set ordered_events by default to true and add a new option
'disable-order' to disable it. For example,
perf report -D --disable-order
Fixes: 977f739b71 ("perf report: Disable ordered_events for raw dump")
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210219070005.12397-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The current fixed metadata version format (version 0), means that adding
metadata parameter items renders files from a previous version of perf
unreadable. Per CPU parameters appear in a fixed order, but there is no
field to indicate the number of ETM parameters per CPU.
This patch updates the per CPU parameter blocks to include a NR_PARAMs
value which indicates the number of parameters in the block.
The header version is incremented to 1. Fixed ordering is retained,
new ETM parameters are added to the end of the list.
The reader code is updated to be able to read current version 0 files,
For version 1, the reader will read the number of parameters in the
per CPU block. This allows the reader to process older or newer files
that may have different numbers of parameters than in use at the
time perf was built.
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20210202214040.32349-1-mike.leach@linaro.org
Link: https://lore.kernel.org/r/20210224164835.3497311-2-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To get the changes in:
fbcee2ebe8 ("powerpc/32: Always save non volatile GPRs at syscall entry")
That shouldn't cause any change in tooling, just silences the following
tools/perf/ build warning:
Warning: Kernel ABI header at 'tools/perf/arch/powerpc/entry/syscalls/syscall.tbl' differs from latest version at 'arch/powerpc/kernel/syscalls/syscall.tbl'
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf tool updates from Arnaldo Carvalho de Melo:
"New features:
- Support instruction latency in 'perf report', with both memory
latency (weight) and instruction latency information, users can
locate expensive load instructions and understand time spent in
different stages.
- Extend 'perf c2c' to display the number of loads which were blocked
by data or address conflict.
- Add 'perf stat' support for L2 topdown events in systems such as
Intel's Sapphire rapids server.
- Add support for PERF_SAMPLE_CODE_PAGE_SIZE in various tools, as a
sort key, for instance:
perf report --stdio --sort=comm,symbol,code_page_size
- New 'perf daemon' command to run long running sessions while
providing a way to control the enablement of events without
restarting a traditional 'perf record' session.
- Enable counting events for BPF programs in 'perf stat' just like
for other targets (tid, cgroup, cpu, etc), e.g.:
# perf stat -e ref-cycles,cycles -b 254 -I 1000
1.487903822 115,200 ref-cycles
1.487903822 86,012 cycles
2.489147029 80,560 ref-cycles
2.489147029 73,784 cycles
^C
The example above counts 'cycles' and 'ref-cycles' of BPF program
of id 254. It is similar to bpftool-prog-profile command, but more
flexible.
- Support the new layout for PERF_RECORD_MMAP2 to carry the DSO
build-id using infrastructure generalised from the eBPF subsystem,
removing the need for traversing the perf.data file to collect
build-ids at the end of 'perf record' sessions and helping with
long running sessions where binaries can get replaced in updates,
leading to possible mis-resolution of symbols.
- Support filtering by hex address in 'perf script'.
- Support DSO filter in 'perf script', like in other perf tools.
- Add namespaces support to 'perf inject'
- Add support for SDT (Dtrace Style Markers) events on ARM64.
perf record:
- Fix handling of eventfd() when draining a buffer in 'perf record'.
- Improvements to the generation of metadata events for pre-existing
threads (mmaps, comm, etc), speeding up the work done at the start
of system wide or per CPU 'perf record' sessions.
Hardware tracing:
- Initial support for tracing KVM with Intel PT.
- Intel PT fixes for IPC
- Support Intel PT PSB (synchronization packets) events.
- Automatically group aux-output events to overcome --filter syntax.
- Enable PERF_SAMPLE_DATA_SRC on ARMs SPE.
- Update ARM's CoreSight hardware tracing OpenCSD library to v1.0.0.
perf annotate TUI:
- Fix handling of 'k' ("show line number") hotkey
- Fix jump parsing for C++ code.
perf probe:
- Add protection to avoid endless loop.
cgroups:
- Avoid reading cgroup mountpoint multiple times, caching it.
- Fix handling of cgroup v1/v2 in mixed hierarchy.
Symbol resolving:
- Add OCaml symbol demangling.
- Further fixes for handling PE executables when using perf with Wine
and .exe/.dll files.
- Fix 'perf unwind' DSO handling.
- Resolve symbols against debug file first, to deal with artifacts
related to LTO.
- Fix gap between kernel end and module start on powerpc.
Reporting tools:
- The DSO filter shouldn't show samples in unresolved maps.
- Improve debuginfod support in various tools.
build ids:
- Fix 16-byte build ids in 'perf buildid-cache', add a 'perf test'
entry for that case.
perf test:
- Support for PERF_SAMPLE_WEIGHT_STRUCT.
- Add test case for PERF_SAMPLE_CODE_PAGE_SIZE.
- Shell based tests for 'perf daemon's commands ('start', 'stop,
'reconfig', 'list', etc).
- ARM cs-etm 'perf test' fixes.
- Add parse-metric memory bandwidth testcase.
Compiler related:
- Fix 'perf probe' kretprobe issue caused by gcc 11 bug when used
with -fpatchable-function-entry.
- Fix ARM64 build with gcc 11's -Wformat-overflow.
- Fix unaligned access in sample parsing test.
- Fix printf conversion specifier for IP addresses on arm64, s390 and
powerpc.
Arch specific:
- Support exposing Performance Monitor Counter SPRs as part of
extended regs on powerpc.
- Add JSON 'perf stat' metrics for ARM64's imx8mp, imx8mq and imx8mn
DDR, fix imx8mm ones.
- Fix common and uarch events for ARM64's A76 and Ampere eMag"
* tag 'perf-tools-for-v5.12-2020-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (148 commits)
perf buildid-cache: Don't skip 16-byte build-ids
perf buildid-cache: Add test for 16-byte build-id
perf symbol: Remove redundant libbfd checks
perf test: Output the sub testing result in cs-etm
perf test: Suppress logs in cs-etm testing
perf tools: Fix arm64 build error with gcc-11
perf intel-pt: Add documentation for tracing virtual machines
perf intel-pt: Split VM-Entry and VM-Exit branches
perf intel-pt: Adjust sample flags for VM-Exit
perf intel-pt: Allow for a guest kernel address filter
perf intel-pt: Support decoding of guest kernel
perf machine: Factor out machine__idle_thread()
perf machine: Factor out machines__find_guest()
perf intel-pt: Amend decoder to track the NR flag
perf intel-pt: Retain the last PIP packet payload as is
perf intel_pt: Add vmlaunch and vmresume as branches
perf script: Add branch types for VM-Entry and VM-Exit
perf auxtrace: Automatically group aux-output events
perf test: Fix unaligned access in sample parsing test
perf tools: Support arch specific PERF_SAMPLE_WEIGHT_STRUCT processing
...
The CoreSight testing contains sub cases, e.g. every CPU iterates the
possible conntected sinks and tests the paths between the associated ETM
with the found sink. Besides the per-thread testing, it also contains
system wide testing and snapshot testing.
To easier observe results for the sub cases, this patch introduces a new
function arm_cs_report(), it outputs the result as "PASS" or "FAIL" for
every sub case; and it records the error in the variable "glb_err" which
is used as the final return value when exits the testing.
Before:
# perf test 73 -v
73: Check Arm CoreSight trace data recording and synthesized samples:
--- start ---
test child forked, pid 17423
Recording trace (only user mode) with path: CPU0 => tmc_etf0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
Recording trace (only user mode) with path: CPU0 => tmc_etr0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
[...]
After:
# perf test 73 -v
73: Check Arm CoreSight trace data recording and synthesized samples:
--- start ---
test child forked, pid 17423
Recording trace (only user mode) with path: CPU0 => tmc_etf0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
CoreSight path testing (CPU0 -> tmc_etf0): PASS
Recording trace (only user mode) with path: CPU0 => tmc_etr0
Looking at perf.data file for dumping branch samples:
Looking at perf.data file for reporting branch samples:
Looking at perf.data file for instruction samples:
CoreSight path testing (CPU0 -> tmc_etr0): PASS
[...]
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Basil Eljuse <basil.eljuse@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: http://lore.kernel.org/lkml/20210215115944.535986-3-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The PIP packet NR (non-root) flag indicates whether or not a virtual
machine is being traced (NR=1 => VM). Add support for tracking its value.
In particular note that the PIP packet (outside of PSB+) will be
associated with a TIP packet from which address the NR value takes
effect. At that point, there is a branch from_ip, to_ip with
corresponding from_nr and to_nr.
In the event of VM-Entry failure, there should still PIP and TIP packets
that can be followed in the same way.
Also note that this assumes that a host VMM is not employing VMX controls
that affect Intel PT, e.g. to hide the host from a guest using Intel PT.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20210218095801.19576-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
aux-output events need to have an AUX area event as the group leader.
However, grouping events does not allow the AUX area event to be given
an address filter because the --filter option must come after the event,
which conflicts with the grouping syntax.
To allow filtering in that case, automatically create a group since that
is the requirement anyway.
Example: (requires Intel Tremont)
perf record -c 500 -e 'intel_pt//u' --filter 'filter main @ /bin/ls' -e 'cycles/aux-output/pp' ls
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20210121140418.14705-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The ubsan reported the following error. It was because sample's raw
data missed u32 padding at the end. So it broke the alignment of the
array after it.
The raw data contains an u32 size prefix so the data size should have
an u32 padding after 8-byte aligned data.
27: Sample parsing :util/synthetic-events.c:1539:4:
runtime error: store to misaligned address 0x62100006b9bc for type
'__u64' (aka 'unsigned long long'), which requires 8 byte alignment
0x62100006b9bc: note: pointer points here
00 00 00 00 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
#0 0x561532a9fc96 in perf_event__synthesize_sample util/synthetic-events.c:1539:13
#1 0x5615327f4a4f in do_test tests/sample-parsing.c:284:8
#2 0x5615327f3f50 in test__sample_parsing tests/sample-parsing.c:381:9
#3 0x56153279d3a1 in run_test tests/builtin-test.c:424:9
#4 0x56153279c836 in test_and_print tests/builtin-test.c:454:9
#5 0x56153279b7eb in __cmd_test tests/builtin-test.c:675:4
#6 0x56153279abf0 in cmd_test tests/builtin-test.c:821:9
#7 0x56153264e796 in run_builtin perf.c:312:11
#8 0x56153264cf03 in handle_internal_command perf.c:364:8
#9 0x56153264e47d in run_argv perf.c:408:2
#10 0x56153264c9a9 in main perf.c:538:3
#11 0x7f137ab6fbbc in __libc_start_main (/lib64/libc.so.6+0x38bbc)
#12 0x561532596828 in _start ...
SUMMARY: UndefinedBehaviorSanitizer: misaligned-pointer-use
util/synthetic-events.c:1539:4 in
Fixes: 045f8cd854 ("perf tests: Add a sample parsing test")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210214091638.519643-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For X86, the var2_w field of PERF_SAMPLE_WEIGHT_STRUCT stands for the
instruction latency. Current perf forces the var2_w to the data->ins_lat
in the generic code. It works well for now because X86 is the only
architecture that supports the PERF_SAMPLE_WEIGHT_STRUCT, but it may
bring problems once other architectures support the sample type. For
example, the var2_w may be used to capture something else on PowerPC.
Create two architecture specific functions to parse and synthesize the
weight related samples. Move the X86 specific codes to the X86 version
functions. Other architectures can implement their own functions later
separately.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/1612540912-6562-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>