Pull perf updates from Ingo Molnar:
"This update is pretty big and almost exclusively includes tooling
changes, because v4.9's LTS status forced to completion most of the
pending kernel side hardware enablement work and because we tried to
freeze core perf work a bit to give a time window for the fuzzing
efforts.
The diff is large mostly due to the JSON hardware event tables added
for Intel and Power8 CPUs. This was a popular feature request from
people working close to hardware and from the HPC community.
Tree size is big because this added the CPU event tables for over a
decade of Intel CPUs. Future changes for a CPU vendor alrady support
should be much smaller, as events for new models are added. The new
events are listed in 'perf list', for the CPU model the tool is
running on. If you find an interesting event it can be used as-is:
$ perf stat -a -e l2_lines_out.pf_clean sleep 1
Performance counter stats for 'system wide':
7,860,403 l2_lines_out.pf_clean
1.000624918 seconds time elapsed
The event lists can be searched the usual 'perf list' fashion for
(case insensitive) substrings as well:
$ perf list l2_lines_out
List of pre-defined events (to be used in -e):
cache:
l2_lines_out.demand_clean
[Clean L2 cache lines evicted by demand]
l2_lines_out.demand_dirty
[Dirty L2 cache lines evicted by demand]
l2_lines_out.dirty_all
[Dirty L2 cache lines filling the L2]
l2_lines_out.pf_clean
[Clean L2 cache lines evicted by L2 prefetch]
l2_lines_out.pf_dirty
[Dirty L2 cache lines evicted by L2 prefetch]
etc.
There's a few high level categories as well that can be listed:
'cache', 'floating point', 'frontend', 'memory', 'pipeline', 'virtual
memory'.
Existing generic events and workflows should work as-is.
The only kernel side change is a late breaking fix for an older
regression, related to Intel BTS, LBR and PT feature interaction.
On the tooling side there are three new tools / major features:
- The new 'perf c2c' tool provides means for Shared Data C2C/HITM
analysis.
This allows you to track down cacheline contention. The tool is
based on x86's load latency and precise store facility events
provided by Intel CPUs.
It was tested by Joe Mario and has proven to be useful, finding
some cacheline contentions. Joe also wrote a blog about c2c tool
with examples:
https://joemario.github.io/blog/2016/09/01/c2c-blog/
excerpt of the content on this site:
At a high level, “perf c2c” will show you:
* The cachelines where false sharing was detected.
* The readers and writers to those cachelines, and the offsets where those accesses occurred.
* The pid, tid, instruction addr, function name, binary object name for those readers and writers.
* The source file and line number for each reader and writer.
* The average load latency for the loads to those cachelines.
* Which numa nodes the samples a cacheline came from and which CPUs were involved.
Using perf c2c is similar to using the Linux perf tool today.
First collect data with “perf c2c record”, then generate a
report output with “perf c2c report”
There one finds extensive details on using the tool, with tips on
reducing the volume of samples while still capturing enough to do
its job. (Dick Fowles, Joe Mario, Don Zickus, Jiri Olsa)
- The new 'perf sched timehist' tool provides tailored analysis of
scheduling events.
Example usage:
perf sched record -- sleep 1
perf sched timehist
By default it shows the individual schedule events, including the
wait time (time between sched-out and next sched-in events for the
task), the task scheduling delay (time between wakeup and actually
running) and run time for the task:
time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
-------- ------ ---------------- --------- --------- --------
1.874569 [0011] gcc[31949] 0.014 0.000 1.148
1.874591 [0010] gcc[31951] 0.000 0.000 0.024
1.874603 [0010] migration/10[59] 3.350 0.004 0.011
1.874604 [0011] <idle> 1.148 0.000 0.035
1.874723 [0005] <idle> 0.016 0.000 1.383
1.874746 [0005] gcc[31949] 0.153 0.078 0.022
...
Times are in msec.usec. (David Ahern, Namhyung Kim)
- Add CPU vendor hardware event tables:
Add JSON files with vendor event naming for Intel and Power8
processors, allowing users of tools like oprofile to keep using the
event names they are used to, as well as people reading vendor
documentation, where such naming is used. (Andi Kleen, Sukadev
Bhattiprolu)
You should see all the new events with 'perf list' and you should
be able to search them, for example 'perf list miss' will list all
the myriads of miss events.
Other tooling features added were:
- Cross-arch annotation support:
o Improve ARM support in the annotation code, affecting 'perf
annotate', 'perf report' and live annotation in 'perf top' (Kim
Phillips)
o Initial support for PowerPC in the annotation code (Ravi
Bangoria)
o Support AArch64 in the 'annotate' code, native/local and
cross-arch/remote (Kim Phillips)
- Allow considering just events in a given time interval, via the
'--time start.s.ms,end.s.ms' command line, added to 'perf kmem',
'perf report', 'perf sched timehist' and 'perf script' (David
Ahern)
- Add option to stop printing a callchain at one of a given group of
symbol names (David Ahern)
- Track memory freed in 'perf kmem stat' (David Ahern)
- Allow querying and setting .perfconfig variables (Taeung Song)
- Show branch information in callchains (predicted, TSX aborts, loop
iteractions, etc) (Jin Yao)
- Dynamicly change verbosity level by pressing 'V' in the 'perf
top/report' hists TUI browser (Alexis Berlemont)
- Implement 'perf trace --delay' in the same fashion as in 'perf
record --delay', to skip sampling workload initialization events
(Alexis Berlemont)
- Make vendor named events case insensitive in 'perf list', i.e.
'perf list LONGEST_LAT' works just the same as 'perf list
longest_lat' (Andi Kleen)
- Add unwinding support for jitdump (Stefano Sanfilippo)
Tooling infrastructure changes:
- Support linking perf with clang and LLVM libraries, initially
statically, but this limitation will be lifted and shared
libraries, when available, will be preferred to the static build,
that should, as with other features, be enabled explicitly (Wang
Nan)
- Add initial support (and perf test entry) for tooling hooks,
starting with 'record_start' and 'record_end', that will have as
its initial user the eBPF infrastructure, where perf_ prefixed
functions will be JITed and run when such hooks are called (Wang
Nan)
- Implement assorted libbpf improvements (Wang Nan)"
... and lots of other changes, features, cleanups and refactorings I
did not list, see the shortlog and the git log for details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (220 commits)
perf/x86: Fix exclusion of BTS and LBR for Goldmont
perf tools: Explicitly document that --children is enabled by default
perf sched timehist: Cleanup idle_max_cpu handling
perf sched timehist: Handle zero sample->tid properly
perf callchain: Introduce callchain_cursor__copy()
perf sched: Cleanup option processing
perf sched timehist: Improve error message when analyzing wrong file
perf tools: Move perf build related variables under non fixdep leg
perf tools: Force fixdep compilation at the start of the build
perf tools: Move PERF-VERSION-FILE target into rules area
perf build: Check LLVM version in feature check
perf annotate: Show raw form for jump instruction with indirect target
perf tools: Add non config targets
perf tools: Cleanup build directory before each test
perf tools: Move python/perf.so target into rules area
perf tools: Move install-gtk target into rules area
tools build: Move tabs to spaces where suitable
tools build: Make the .cmd file more readable
perf clang: Compile BPF script using builtin clang support
perf clang: Support compile IR to BPF object and add testcase
...
Add a start of a test suite for kernel selftests. This moves test_verifier
and test_maps over to tools/testing/selftests/bpf/ along with various
code improvements and also adds a script for invoking test_bpf module.
The test suite can simply be run via selftest framework, f.e.:
# cd tools/testing/selftests/bpf/
# make
# make run_tests
Both test_verifier and test_maps were kind of misplaced in samples/bpf/
directory and we were looking into adding them to selftests for a while
now, so it can be picked up by kbuild bot et al and hopefully also get
more exposure and thus new test case additions.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
perf tools build in recent kernels spews splat when cross compiling with uClibc:
| CC util/alias.o
| In file included from tools/perf/util/../ui/../util/cache.h:8:0,
| from tools/perf/util/../ui/helpline.h:7,
| from tools/perf/util/debug.h:8,
| from arch/../util/cpumap.h:9,
| from arch/../util/env.h:5,
| from arch/common.h:4,
| from arch/common.c:3:
| tools/include/linux/string.h:12:15: warning: redundant redeclaration of ‘strlcpy’ [-Wredundant-decls]
| extern size_t strlcpy(char *dest, const char *src, size_t size);
^
This is after commit 61a6445e46 ("tools lib: Guard the strlcpy() header with
__GLIBC__").
The problem is uClibc also defines __GLIBC__ for exported headers for
applications. So add that specific check to not trip for uClibc.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petri Gynther <pgynther@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: linux-snps-arc@lists.infradead.org
Link: http://lkml.kernel.org/r/1471537703-16439-1-git-send-email-vgupta@synopsys.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The objtool build fails with the recent changes to the bits-per-long
headers:
tools/include/linux/bitops.h:12:0: error: "BITS_PER_LONG" redefined [-Werror]
Which got introduced by:
bb9707077b tools: Copy the bitsperlong.h files from the kernel
Work it around for the time being.
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The tools so far have been using the strerror_r() GNU variant, that
returns a string, be it the buffer passed or something else.
But that, besides being tricky in cases where we expect that the
function using strerror_r() returns the error formatted in a provided
buffer (we have to check if it returned something else and copy that
instead), breaks the build on systems not using glibc, like Alpine
Linux, where musl libc is used.
So, introduce yet another wrapper, str_error_r(), that has the GNU
interface, but uses the portable XSI variant of strerror_r(), so that
users rest asured that the provided buffer is used and it is what is
returned.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf fixes from Ingo Molnar:
"This tree contains various perf fixes on the kernel side, plus three
hw/event-enablement late additions:
- Intel Memory Bandwidth Monitoring events and handling
- the AMD Accumulated Power Mechanism reporting facility
- more IOMMU events
... and a final round of perf tooling updates/fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
perf llvm: Use strerror_r instead of the thread unsafe strerror one
perf llvm: Use realpath to canonicalize paths
perf tools: Unexport some methods unused outside strbuf.c
perf probe: No need to use formatting strbuf method
perf help: Use asprintf instead of adhoc equivalents
perf tools: Remove unused perf_pathdup, xstrdup functions
perf tools: Do not include stringify.h from the kernel sources
tools include: Copy linux/stringify.h from the kernel
tools lib traceevent: Remove redundant CPU output
perf tools: Remove needless 'extern' from function prototypes
perf tools: Simplify die() mechanism
perf tools: Remove unused DIE_IF macro
perf script: Remove lots of unused arguments
perf thread: Rename perf_event__preprocess_sample_addr to thread__resolve
perf machine: Rename perf_event__preprocess_sample to machine__resolve
perf tools: Add cpumode to struct perf_sample
perf tests: Forward the perf_sample in the dwarf unwind test
perf tools: Remove misplaced __maybe_unused
perf list: Fix documentation of :ppp
perf bench numa: Fix assertion for nodes bitfield
...
Vinson reported build breakage with gcc 4.4 due to strict-aliasing.
CC util/annotate.o
cc1: warnings being treated as errors
util/annotate.c: In function ‘disasm__purge’:
linux-next/tools/include/linux/compiler.h:66: error: dereferencing
pointer ‘res.41’ does break strict-aliasing rules
The reason is READ_ONCE/WRITE_ONCE code we took from kernel sources. They
intentionaly break aliasing rules. While this is ok for kernel because it's
built with -fno-strict-aliasing, it breaks perf which is build with
-Wstrict-aliasing=3.
Using extra __may_alias__ type to allow aliasing in this case.
Reported-and-tested-by: Vinson Lee <vlee@twopensource.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Martin Liska <mliska@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rabin Vincent <rabin@rab.in>
Cc: linux-next@vger.kernel.org
Link: http://lkml.kernel.org/r/20151013085214.GB2705@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The error variable breaks build on CentOS 6.7, due to collision with
global error symbol:
CC util/evlist.o
cc1: warnings being treated as errors
In file included from util/evlist.c:28:
tools/include/linux/err.h: In function ‘ERR_PTR’:
tools/include/linux/err.h:34: error: declaration of ‘error’ shadows a global declaration
util/util.h:135: error: shadowed declaration is here
Using 'error_' name instead to fix it.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/n/tip-i9mdgdbrgauy3fe76s9rd125@git.kernel.org
Reported-by: Vinson Lee <vlee@twopensource.com>
[ Use 'error_' instead of 'err' to, visually, not diverge too much from include/linux/err.h ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>