Tracing a workload that uses transactions gave a seg fault as follows:
perf record -e intel_pt// workload
perf report
Program received signal SIGSEGV, Segmentation fault.
0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110)
at util/intel-pt.c:929
929 ptq->last_branch_rb->nr = 0;
(gdb) p ptq->last_branch_rb
$1 = (struct branch_stack *) 0x0
(gdb) up
1148 intel_pt_reset_last_branch_rb(ptq);
(gdb) l
1143 if (ret)
1144 pr_err("Intel Processor Trace: failed to deliver transaction event
1145 ret);
1146
1147 if (pt->synth_opts.callchain)
1148 intel_pt_reset_last_branch_rb(ptq);
1149
1150 return ret;
1151 }
1152
(gdb) p pt->synth_opts.callchain
$2 = true
(gdb)
(gdb) bt
#0 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110)
#1 0x000000000054c1e0 in intel_pt_synth_transaction_sample (ptq=0x1a36110)
#2 0x000000000054c5b2 in intel_pt_sample (ptq=0x1a36110)
Caused by checking the 'callchain' flag when it should have been the
'last_branch' flag. Fix that.
Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: f14445ee72 ("perf intel-pt: Support generating branch stack")
Link: http://lkml.kernel.org/r/1460977068-11566-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 9b07e27f88 ("perf inject: Add jitdump mmap injection support")
incorrectly assumed that PowerPC is big endian only.
Simplify things by consolidating the define of GEN_ELF_ENDIAN and checking
for __BYTE_ORDER == __BIG_ENDIAN.
The PowerPC checks were also incorrect, they do not match what gcc
emits. We should first look for __powerpc64__, then __powerpc__.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carl Love <cel@us.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 9b07e27f88 ("perf inject: Add jitdump mmap injection support")
Link: http://lkml.kernel.org/r/20160329175944.33a211cc@kryten
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 4b3a321223 ("perf hists browser: Support flat callchains") commit
over-aggressively tried to optimize callchain_node__init_have_children().
That lead to --tui mode not allowing to expand call chain elements if a
call chain element had only one parent. That's why --inverted callgraphs
looked halfway sane, but plain ones didn't.
Revert that individual optimization, it wasn't really related to the
rest of the commit.
Signed-off-by: Andres Freund <andres@anarazel.de>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Fixes: 4b3a321223 ("perf hists browser: Support flat callchains")
Link: http://lkml.kernel.org/r/20160330190245.GB13305@awork2.anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In 473398a21d ("perf tools: Add cpumode to struct perf_sample"), I
missed some places where perf_sample fields are directly initialized in
addition to what is done in perf_evsel__parse_sample(), namely when
synthesizing PERF_RECORD_{MMAP*,COMM,FORK,EXIT} for pre-existing threads
and also in intel_pt and intel_bts when synthesizing events from
processor trace, the jitdump code also was affected, fix it.
The problem was noticed with running:
# perf record -e intel_pt//u true
# perf script
Where the samples wouldn't get resolved because perf_sample.cpumode
would be left as zero, i.e. PERF_RECORD_MISC_CPUMODE_UNKNOWN, not
resolving as kernel, hypervisor or user cpu modes.
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 473398a21d ("perf tools: Add cpumode to struct perf_sample")
Link: http://lkml.kernel.org/n/tip-n5sdauxgk24d5nun8kuuu2mh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 531d241063 ("perf tools: Do not include stringify.h from the
kernel sources") seems to have accidentially removed the inclusion of
"util/header.h" from "arch/powerpc/util/header.c".
"util/header.h" provides the prototype for get_cpuid() and is needed to
build perf on Powerpc:
arch/powerpc/util/header.c:17:1: error: no previous prototype for 'get_cpuid' [-Werror=missing-prototypes]
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 531d241063 ("perf tools: Do not include stringify.h from the kernel sources")
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
[ Included "util.h" too, to get the scnprintf() prototype ]
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
...
A change on kernel files included by the 'perf bench memcpy' code grew some new
include deps, breaking the detached tarball build:
$ make -C tools/perf build-test
make: Entering directory '/home/acme/git/linux/tools/perf'
- tarpkg: ./tests/perf-targz-src-pkg .
tests/make:302: recipe for target 'tarpkg' failed
make[1]: *** [tarpkg] Error 2
Makefile:102: recipe for target 'build-test' failed
make: *** [build-test] Error 2
make: Leaving directory '/home/acme/git/linux/tools/perf'
$ cat tools/perf/tarpkg
./tests/perf-targz-src-pkg .
PERF_VERSION = 4.5.g05f5ec
PERF_VERSION = 4.5.g05f5ec
In file included from bench/mem-memcpy-x86-64-asm.S:9:0:
bench/../../../arch/x86/lib/memcpy_64.S:5:29: fatal error: asm/cpufeatures.h: No such file or directory
compilation terminated.
mv: cannot stat ‘bench/.mem-memcpy-x86-64-asm.o.tmp’: No such file or directory
make[5]: *** [bench/mem-memcpy-x86-64-asm.o] Error 1
make[5]: *** Waiting for unfinished jobs....
make[4]: *** [bench] Error 2
make[4]: *** Waiting for unfinished jobs....
make[3]: *** [perf-in.o] Error 2
make[3]: *** Waiting for unfinished jobs....
make[2]: *** [all] Error 2
$
Add arch/*/include/asm/*features.h to tools/perf/MANIFEST so that we can
continue to use detached tarballs to build perf.
Now it builds ok, doing it manually:
$ make help | grep perf
perf-tar-src-pkg - Build perf-4.5.0.tar source tarball
perf-targz-src-pkg - Build perf-4.5.0.tar.gz source tarball
perf-tarbz2-src-pkg - Build perf-4.5.0.tar.bz2 source tarball
perf-tarxz-src-pkg - Build perf-4.5.0.tar.xz source tarball
$ ls -la perf-4.5.0.tar
ls: cannot access perf-4.5.0.tar: No such file or directory
$ make perf-tar-src-pkg
TAR
PERF_VERSION = 4.5.g32c25b
$ ls -la perf-4.5.0.tar
-rw-rw-r--. 1 acme acme 6318080 Mar 24 11:52 perf-4.5.0.tar
$ mv perf-4.5.0.tar /tmp
$ cd /tmp
$ tar xf perf-4.5.0.tar
$ cd perf-4.5.0/tools/perf
$ make > /dev/null
PERF_VERSION = 4.5.g32c25b
$ ls -la perf
-rwxrwxr-x. 1 acme acme 14046416 Mar 24 11:53 perf
$ ./perf --version
perf version 4.5.g32c25b
$ perf bench
Usage:
perf bench [<common options>] <collection> <benchmark> [<options>]
# List of all available benchmark collections:
sched: Scheduler and IPC benchmarks
mem: Memory access benchmarks
numa: NUMA scheduling and MM benchmarks
futex: Futex stressing benchmarks
all: All benchmarks
$ perf bench mem
# List of available benchmarks for collection 'mem':
memcpy: Benchmark for memcpy() functions
memset: Benchmark for memset() functions
all: Run all memory access benchmarks
$ perf bench mem memcpy
# Running 'mem/memcpy' benchmark:
# function 'default' (Default memcpy() provided by glibc)
# Copying 1MB bytes ...
15.024038 GB/sec
# function 'x86-64-unrolled' (unrolled memcpy() in arch/x86/lib/memcpy_64.S)
# Copying 1MB bytes ...
17.438616 GB/sec
# function 'x86-64-movsq' (movsq-based memcpy() in arch/x86/lib/memcpy_64.S)
# Copying 1MB bytes ...
25.040064 GB/sec
# function 'x86-64-movsb' (movsb-based memcpy() in arch/x86/lib/memcpy_64.S)
# Copying 1MB bytes ...
25.040064 GB/sec
$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
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-2c2sncwffuabw58fj1pw86gu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So we need to trow away just stdout, leaving stderr to be caught by
the build tests infrastructure, so that we can see what went wrong
when the tarpkg build test fails:
$ make -C tools/perf build-test
make: Entering directory '/home/acme/git/linux/tools/perf'
- tarpkg: ./tests/perf-targz-src-pkg .
tests/make:302: recipe for target 'tarpkg' failed
make[1]: *** [tarpkg] Error 2
Makefile:102: recipe for target 'build-test' failed
make: *** [build-test] Error 2
make: Leaving directory '/home/acme/git/linux/tools/perf'
$ cat tools/perf/tarpkg
./tests/perf-targz-src-pkg .
PERF_VERSION = 4.5.g05f5ec
PERF_VERSION = 4.5.g05f5ec
In file included from bench/mem-memcpy-x86-64-asm.S:9:0:
bench/../../../arch/x86/lib/memcpy_64.S:5:29: fatal error: asm/cpufeatures.h: No such file or directory
compilation terminated.
mv: cannot stat ‘bench/.mem-memcpy-x86-64-asm.o.tmp’: No such file or directory
make[5]: *** [bench/mem-memcpy-x86-64-asm.o] Error 1
make[5]: *** Waiting for unfinished jobs....
make[4]: *** [bench] Error 2
make[4]: *** Waiting for unfinished jobs....
make[3]: *** [perf-in.o] Error 2
make[3]: *** Waiting for unfinished jobs....
make[2]: *** [all] Error 2
$
So the test flow is:
1. Run: 'make -C tools/perf build-test'
2. One of its tests failed, in this case, the 'tarpkg' one
3. Look at what went wrong, by looking at the output of that test, in
tools/perf/tarpkg
Admittedly, this should be shortcircuited to showing what went wrong directly
from the 'make build-test' step, but lets first fix this tarpkg one and the
problem it spotted, which should be fixed by adding some extra file to the
tools/perf/MANIFEST so that detached tarballs continue being self contained and
build successfully.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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-ynld6egoxolmftcddpnd7oh6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.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-5njrq9dltckgm624omw9ljgu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To kill the last user of make_nonrelative_path(), that gets ditched,
one more panicking function killed.
Cc: Adrian Hunter <adrian.hunter@intel.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-3hu56rvyh4q5gxogovb6ko8a@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.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-nq1wvtky4mpu0nupjyar7sbw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have addch() for chars, add() for fixed size data, and addstr() for
variable length strings, use them.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0ap02fn2xtvpduj2j6b2o1j4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That doesn't chekcs malloc return and that, when using strbuf, if it
can't grow, just explodes away via die().
Cc: Adrian Hunter <adrian.hunter@intel.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-vr8qsjbwub7e892hpa9msz95@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.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-s87zi5d03m6rz622y1z6rlsa@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use instead the copy just made to tools/include/linux/.
Cc: Adrian Hunter <adrian.hunter@intel.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-q736w12nwy98x5ox2hamp5ow@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.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-w246stf7ponfamclsai6b9zo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This should die altogether, but for now lets remove a bit of this stuff,
as it is not used at all.
Cc: Adrian Hunter <adrian.hunter@intel.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-ade3n99xscldhg5mx2vzd8p3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.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-elxg25jd4dhwod4wqbko87qh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since none of the perf_event fields are used anymore, just the
perf_sample ones, and since this resolves to (map, symbol) from data
structures within struct thread, rename it to thread__resolve and make
the argument ordering similar to the one in machine__resolve().
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2b33hs9bp550tezzlhl4kejh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since we only deal with fields in the passed struct perf_sample move
this method to struct machine, that is where the perf_sample fields
will be resolved to a struct addr_location, i.e. thread, map, symbol,
etc.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-a1ww2lbm2vbuqsv4p7ilubu9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To avoid parsing event->header.misc in many locations.
This will also allow setting perf.sample.{ip,cpumode} in a single place,
from tracepoint fields, as needed by 'perf kvm' with PPC guests, where
the guest hardware counters is not available at the host.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-qp3yradhyt6q3wl895b1aat0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It _will_ be used, no sense in receiving it and nor fowarding it along.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ht8v5et209wuoh5o6nh9pzyq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
All over the tree.
Cc: David Ahern <dsahern@gmail.com>
cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-8nzhnokxyp8y4v7gf0j00oyb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Correctly document what is implemented for :ppp on Intel CPUs in recent
kernels.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1458575793-12091-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Comparing bits and bytes in numa benchmark assertion
I hit the issue on two socket Power8 machine presenting its numa nodes
as 0,1,16,17 (according to numactl). Therefore I got error (and hang of
parent process):
perf: bench/numa.c:296: bind_to_memnode: Assertion `!(g->p.nr_nodes > (int)sizeof(nodemask))' failed.
This is obviously false positive. We can fit all the 18 nodes into
bitfield of 8 bytes (long on 64b architecture).
Signed-off-by: Jakub Jelen <jakuje@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jakub Jelen <jjelen@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: trivial@kernel.org
Link: http://lkml.kernel.org/r/1458388687-24421-1-git-send-email-jakuje@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull 'objtool' stack frame validation from Ingo Molnar:
"This tree adds a new kernel build-time object file validation feature
(ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation.
It was written by and is maintained by Josh Poimboeuf.
The motivation: there's a category of hard to find kernel bugs, most
of them in assembly code (but also occasionally in C code), that
degrades the quality of kernel stack dumps/backtraces. These bugs are
hard to detect at the source code level. Such bugs result in
incorrect/incomplete backtraces most of time - but can also in some
rare cases result in crashes or other undefined behavior.
The build time correctness checking is done via the new 'objtool'
user-space utility that was written for this purpose and which is
hosted in the kernel repository in tools/objtool/. The tool's (very
simple) UI and source code design is shaped after Git and perf and
shares quite a bit of infrastructure with tools/perf (which tooling
infrastructure sharing effort got merged via perf and is already
upstream). Objtool follows the well-known kernel coding style.
Objtool does not try to check .c or .S files, it instead analyzes the
resulting .o generated machine code from first principles: it decodes
the instruction stream and interprets it. (Right now objtool supports
the x86-64 architecture.)
From tools/objtool/Documentation/stack-validation.txt:
"The kernel CONFIG_STACK_VALIDATION option enables a host tool named
objtool which runs at compile time. It has a "check" subcommand
which analyzes every .o file and ensures the validity of its stack
metadata. It enforces a set of rules on asm code and C inline
assembly code so that stack traces can be reliable.
Currently it only checks frame pointer usage, but there are plans to
add CFI validation for C files and CFI generation for asm files.
For each function, it recursively follows all possible code paths
and validates the correct frame pointer state at each instruction.
It also follows code paths involving special sections, like
.altinstructions, __jump_table, and __ex_table, which can add
alternative execution paths to a given instruction (or set of
instructions). Similarly, it knows how to follow switch statements,
for which gcc sometimes uses jump tables."
When this new kernel option is enabled (it's disabled by default), the
tool, if it finds any suspicious assembly code pattern, outputs
warnings in compiler warning format:
warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch
warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup
warning: objtool:__schedule()+0x3c0: duplicate frame pointer save
warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer
... so that scripts that pick up compiler warnings will notice them.
All known warnings triggered by the tool are fixed by the tree, most
of the commits in fact prepare the kernel to be warning-free. Most of
them are bugfixes or cleanups that stand on their own, but there are
also some annotations of 'special' stack frames for justified cases
such entries to JIT-ed code (BPF) or really special boot time code.
There are two other long-term motivations behind this tool as well:
- To improve the quality and reliability of kernel stack frames, so
that they can be used for optimized live patching.
- To create independent infrastructure to check the correctness of
CFI stack frames at build time. CFI debuginfo is notoriously
unreliable and we cannot use it in the kernel as-is without extra
checking done both on the kernel side and on the build side.
The quality of kernel stack frames matters to debuggability as well,
so IMO we can merge this without having to consider the live patching
or CFI debuginfo angle"
* 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
objtool: Only print one warning per function
objtool: Add several performance improvements
tools: Copy hashtable.h into tools directory
objtool: Fix false positive warnings for functions with multiple switch statements
objtool: Rename some variables and functions
objtool: Remove superflous INIT_LIST_HEAD
objtool: Add helper macros for traversing instructions
objtool: Fix false positive warnings related to sibling calls
objtool: Compile with debugging symbols
objtool: Detect infinite recursion
objtool: Prevent infinite recursion in noreturn detection
objtool: Detect and warn if libelf is missing and don't break the build
tools: Support relative directory path for 'O='
objtool: Support CROSS_COMPILE
x86/asm/decoder: Use explicitly signed chars
objtool: Enable stack metadata validation on 64-bit x86
objtool: Add CONFIG_STACK_VALIDATION option
objtool: Add tool to perform compile-time stack metadata validation
x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard
sched: Always inline context_switch()
...
Store DSO's .text offset into DSO, used for VDSOs and will also be used for
other needs, like handling kernel modules.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Cody P Schafer <dev@codyps.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kirill Smelkov <kirr@nexedi.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456479154-136027-2-git-send-email-wangnan0@huawei.com
[ Extracted from larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As it is used by several other tools, better move it outside tools/perf.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-34s9kue3xq9w5mijdmfrfx8s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In tracepoints, it's possible to print gfp flags in a human-friendly
format through a macro show_gfp_flags(), which defines a translation
array and passes is to __print_flags(). Since the following patch will
introduce support for gfp flags printing in printk(), it would be nice
to reuse the array. This is not straightforward, since __print_flags()
can't simply reference an array defined in a .c file such as mm/debug.c
- it has to be a macro to allow the macro magic to communicate the
format to userspace tools such as trace-cmd.
The solution is to create a macro __def_gfpflag_names which is used both
in show_gfp_flags(), and to define the gfpflag_names[] array in
mm/debug.c.
On the other hand, mm/debug.c also defines translation tables for page
flags and vma flags, and desire was expressed (but not implemented in
this series) to use these also from tracepoints. Thus, this patch also
renames the events/gfpflags.h file to events/mmflags.h and moves the
table definitions there, using the same macro approach as for gfpflags.
This allows translating all three kinds of mm-specific flags both in
tracepoints and printk.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When updating tracing's show_gfp_flags() I have noticed that perf's
gfp_compact_table is also outdated. Fill in the missing flags and place
a note in gfp.h to increase chance that future updates are synced.
Convert the __GFP_X flags from "GFP_X" to "__GFP_X" strings in line with
the previous patch.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The topology test case of 'perf test' seems to be broken on my x86
system - due to the comparison of a "core-id" with # of CPUs online.
There are 8 online CPUs:
$ cat /sys/devices/system/cpu/online
0-7
but core-ids are not sequential and some core-ids exceed the number
of online CPUs.
$ cat /sys/devices/system/cpu/cpu?/topology/core_id
0
1
9
10
0
1
9
10
Looks like we can safely remove the check. Output before:
$ perf --version
perf version 4.4.rc1.g34258a
$ perf test -v topo
36: Test topology in session :
--- start ---
test child forked, pid 5906
templ file: /tmp/perf-test-vCwWG3
core_id number is too big.You may need to upgrade the perf tool.
test child interrupted
---- end ----
Test topology in session: FAILED!
and after:
$ perf test -v topo
36: Test topology in session :
--- start ---
test child forked, pid 6532
templ file: /tmp/perf-test-y10wFJ
CPU 0, core 0, socket 0
CPU 1, core 1, socket 0
CPU 2, core 9, socket 0
CPU 3, core 10, socket 0
CPU 4, core 0, socket 1
CPU 5, core 1, socket 1
CPU 6, core 9, socket 1
CPU 7, core 10, socket 1
test child finished with 0
---- end ----
Test topology in session: Ok
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/20151203233219.GA27696@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add metric only support for -A too. This requires a new print function
that prints the metrics in the right order.
v2: Fix manpage
v3: Simplify nrcpus computation
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1457049458-28956-7-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a new mode to only print metrics. Sometimes we don't care about the
raw values, just want the computed metrics. This allows more compact
printing, so with -I each sample is only a single line. This also
allows easier plotting and processing with other tools.
The main target is with using --topdown, but it also works with -T and
standard perf stat. A few metrics are not supported.
To avoiding having to hardcode all the metrics in the code it uses a two
pass approach: first compute dummy metrics and only print the headers in
the print_metric callback. Then use the callback to print the actual
values.
There are some additional changes in the stat printout code to handle
all metrics being on a single line.
One issue is that the column code doesn't know in advance what events
are not supported by the CPU, and it would be hard to find out as this
could change based on dynamic conditions. That causes empty columns in
some cases.
The output can be fairly wide, often you may need more than 80 columns.
Example:
% perf stat -a -I 1000 --metric-only
1.001452803 frontend cycles idle insn per cycle stalled cycles per insn branch-misses of all branches
1.001452803 158.91% 0.66 2.39 2.92%
2.002192321 180.63% 0.76 2.08 2.96%
3.003088282 150.59% 0.62 2.57 2.84%
4.004369835 196.20% 0.98 1.62 3.79%
5.005227314 231.98% 0.84 1.90 4.71%
v2: Lots of updates.
v3: Use slightly narrower columns
v4: Add comment
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1457049458-28956-6-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
With all the recently added fields in the perf stat CSV output we should
finally document them in the man page. Do this here.
v2: Fix fields in documentation (Jiri)
v3: fix order of fields again (Jiri)
v4: Change order again.
v5: Document more fields (Jiri)
v6: Move time stamp first
v7: More fixes (Jiri)
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1457049458-28956-5-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The context menu in TUI hists browser checks corresponding sort keys
when creating the menu item. But hotkey actions lacks these checks so
it can filter using incorrect info.
For example, default sort key of 'perf top' doesn't contain 'comm' or
'pid' sort key so each hist entry's thread info is not reliable. Thus
it should prohibit using thread filter on 't' key.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1457533253-21419-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The commit 2eafd410e6 ("perf hists browser: Only 'Zoom into thread'
only when sort order has 'pid'") disabled thread filtering in hist
browser for the default sort key. However the he->thread is still valid
even if 'pid' sort key is not given. Only thing it should not use is
the pid (or tid) of the thread. So allow to filter by thread when
'comm' sort key is given and show pid only if 'pid' sort key is given.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1457536490-24084-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The sort__has_comm variable is to check whether the comm sort key is
given. This is necessary to support thread filtering in the TUI hists
browser later.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1457533253-21419-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When hierarchy mode is enabled, each entry in a hierarchy level shares
the period. IOW an upper level entry's period is the sum of lower level
entries. Thus perf uses only one of them to calculate the total period
of hists. It was lowest-level (leaf) entries but it has a problem when
it comes to filters.
If a filter is applied, entries in the same level will be filtered or
not. But upper level entries still have period of their sum including
filtered one. So total sum of upper level entries will not be same as
sum of lower level entries.
This resulted in entries having more than 100% of overhead and it can be
produced using perf top with filter(s).
Reported-and-Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-8-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The nr_sort_keys field is to carry the number of sort entries in a
hpp_list or hists to determine the depth of indentation of a hist entry.
As it's only used in hierarchy mode and now we have used nr_hpp_node for
this reason, there's no need to keep it anymore. Let's get rid of it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-7-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The hist_browser__fprintf_hierarchy_entry() if to dump current output
into a file so it needs to be sync-ed with the corresponding function
hist_browser__show_hierarchy_entry(). So use hists->nr_hpp_node to
indent width and use first fmt_node to print overhead columns instead of
checking whether it's a sort entry (or dynamic entry).
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-6-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's not used anymore and the output format is accessed by the hpp_list
pointer instead when hierarchy is enabled. Let's get rid of it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When a command-line filter is applied in hierarchy mode, output is
broken especially when filtering on lower level. The higher level
entries doesn't show up so it's hard to see the results.
Also it needs to handle multi sort keys in a single hierarchy level.
Before:
$ perf report --hierarchy -s 'cpu,{dso,comm}' --comms swapper --stdio
...
# Overhead CPU / Shared Object+Command
# ........... ...........................
#
13.79% [kernel.vmlinux] swapper
31.71% 000
13.80% [kernel.vmlinux] swapper
0.43% [e1000e] swapper
11.89% [kernel.vmlinux] swapper
9.18% [kernel.vmlinux] swapper
After:
# Overhead CPU / Shared Object+Command
# ........... ...............................
#
33.09% 003
13.79% [kernel.vmlinux] swapper
31.71% 000
13.80% [kernel.vmlinux] swapper
0.43% [e1000e] swapper
21.90% 002
11.89% [kernel.vmlinux] swapper
13.30% 001
9.18% [kernel.vmlinux] swapper
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Those functions are for checkinf if a given perf_hpp_fmt is a
filter-related sort entry. With hierarchy mode, it needs to check
filters on the hist entries with its own hpp format list.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When hierarchy mode is enabled each output format is in a separate hpp
list. So when applying a filter it should check all formats in the
list. Currently it only checks a single ->fmt field which was not set
properly.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Build jitdump only on architectures defined in util/genelf.h file, to avoid
breaking the build on such arches.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Mel Gorman <mgorman@suse.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160310164113.GA11357@krava.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no need to use a const char pointer, we can used char pointer
from the beginning and omit the unnecessary cast.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160308184230.GB7897@krava.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pass perf_hpp_list all the way through setup_sort_list so that the sort
entry can be added on the arbitrary list.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20160309100417.GA30910@krava.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ingo Molnar