The itrace "e" option may be followed by flags which affect what errors
will or will not be reported. Each flag must be preceded by either '+' or '-'.
The flags supported by Intel PT are:
-o Suppress overflow errors
-l Suppress trace data lost errors
For example, for errors but not overflow or data lost errors:
--itrace=e-o-l
Suppressing those errors can be useful for testing and debugging because
they are not due to decoding.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200710151104.15137-7-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Allow the 'e' option to be followed by flags which will affect what errors
will or will not be reported. Each flag must be preceded by either '+' or
'-'. The flags are:
o overflow
l trace data lost
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200710151104.15137-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add missing itrace options o, G and L.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200710151104.15137-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
While walking code towards a FUP ip, the packet state is
INTEL_PT_STATE_FUP or INTEL_PT_STATE_FUP_NO_TIP. That was mishandled
resulting in the state becoming INTEL_PT_STATE_IN_SYNC prematurely. The
result was an occasional lost EXSTOP event.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200710151104.15137-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To sync headers, for instance, in this case tools/perf was ahead of
upstream till Linus merged tip/perf/core to get the
PERF_RECORD_TEXT_POKE changes:
Warning: Kernel ABI header at 'tools/include/uapi/linux/perf_event.h' differs from latest version at 'include/uapi/linux/perf_event.h'
diff -u tools/include/uapi/linux/perf_event.h include/uapi/linux/perf_event.h
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since commit 0a892c1c94 ("perf record: Add dummy event during system wide synthesis"),
a dummy event is added to capture mmaps.
But if we run perf-record as,
# perf record -e cycles:p -IXMM0 -a -- sleep 1
Error:
dummy:HG: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'
The issue is, if we enable the extended regs (-IXMM0), but the
pmu->capabilities is not set with PERF_PMU_CAP_EXTENDED_REGS, the kernel
will return -EOPNOTSUPP error.
See following code:
/* in kernel/events/core.c */
static int perf_try_init_event(struct pmu *pmu, struct perf_event *event)
{
....
if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) &&
has_extended_regs(event))
ret = -EOPNOTSUPP;
....
}
For software dummy event, the PMU should not be set with
PERF_PMU_CAP_EXTENDED_REGS. But unfortunately now, the dummy
event has possibility to be set with PERF_REG_EXTENDED_MASK bit.
In evsel__config, /* tools/perf/util/evsel.c */
if (opts->sample_intr_regs) {
attr->sample_regs_intr = opts->sample_intr_regs;
}
If we use -IXMM0, the attr>sample_regs_intr will be set with
PERF_REG_EXTENDED_MASK bit.
It doesn't make sense to set attr->sample_regs_intr for a
software dummy event.
This patch adds dummy event checking before setting
attr->sample_regs_intr and attr->sample_regs_user.
After:
# ./perf record -e cycles:p -IXMM0 -a -- sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.413 MB perf.data (45 samples) ]
Committer notes:
Adrian said this when providing his Acked-by:
"
This is fine. It will not break PT.
no_aux_samples is useful for evsels that have been added by the code rather
than requested by the user. For old kernels PT adds sched_switch tracepoint
to track context switches (before the current context switch event was
added) and having auxiliary sample information unnecessarily uses up space
in the perf buffer.
"
Fixes: 0a892c1c94 ("perf record: Add dummy event during system wide synthesis")
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
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: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200720010013.18238-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce --control fd:ctl-fd[,ack-fd] options to pass open file
descriptors numbers from command line.
Extend perf-record.txt file with --control fd:ctl-fd[,ack-fd] options
description.
Document possible usage model introduced by --control fd:ctl-fd[,ack-fd]
options by providing example bash shell script.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/8dc01e1a-3a80-3f67-5385-4bc7112b0dd3@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Implement handling of 'enable' and 'disable' control commands coming
from control file descriptor.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/f0fde590-1320-dca1-39ff-da3322704d3b@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Extend -D,--delay option with -1 to start collection with events
disabled to be enabled later by 'enable' command provided via control
file descriptor.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/3e7d362c-7973-ee5d-e81e-c60ea22432c3@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce --control fd:ctl-fd[,ack-fd] options to pass open file
descriptors numbers from command line. Extend perf-stat.txt file with
--control fd:ctl-fd[,ack-fd] options description. Document possible
usage model introduced by --control fd:ctl-fd[,ack-fd] options by
providing example bash shell script.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/feabd5cf-0155-fb0a-4587-c71571f2d517@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Minor conflict in tools/perf/arch/arm/util/auxtrace.c as one fix there
was cherry-picked for the last perf/urgent pull req to Linus, so was
already there.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When recording with cache-misses and arm_spe_x event, I found that it
will just fail without showing any error info if i put cache-misses
after 'arm_spe_x' event.
[root@localhost 0620]# perf record -e cache-misses \
-e arm_spe_0/ts_enable=1,pct_enable=1,pa_enable=1,load_filter=1,jitter=1,store_filter=1,min_latency=0/ sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.067 MB perf.data ]
[root@localhost 0620]#
[root@localhost 0620]# perf record -e arm_spe_0/ts_enable=1,pct_enable=1,pa_enable=1,load_filter=1,jitter=1,store_filter=1,min_latency=0/ \
-e cache-misses sleep 1
[root@localhost 0620]#
The current code can only work if the only event to be traced is an
'arm_spe_x', or if it is the last event to be specified. Otherwise the
last event type will be checked against all the arm_spe_pmus[i]->types,
none will match and an out of bound 'i' index will be used in
arm_spe_recording_init().
We don't support concurrent multiple arm_spe_x events currently, that
is checked in arm_spe_recording_options(), and it will show the relevant
info. So add the check and record of the first found 'arm_spe_pmu' to
fix this issue here.
Fixes: ffd3d18c20 ("perf tools: Add ARM Statistical Profiling Extensions (SPE) support")
Signed-off-by: Wei Li <liwei391@huawei.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20200724071111.35593-2-liwei391@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 5aa98879ef ("s390/cpum_sf: prohibit callchain data collection")
prohibits call graph sampling for hardware events on s390. The
information recorded is out of context and does not match.
On s390 this commit now breaks test case 68 Zstd perf.data
compression/decompression.
Therefore omit call graph sampling on s390 in this test.
Output before:
[root@t35lp46 perf]# ./perf test -Fv 68
68: Zstd perf.data compression/decompression :
--- start ---
Collecting compressed record file:
Error:
cycles: PMU Hardware doesn't support sampling/overflow-interrupts.
Try 'perf stat'
---- end ----
Zstd perf.data compression/decompression: FAILED!
[root@t35lp46 perf]#
Output after:
[root@t35lp46 perf]# ./perf test -Fv 68
68: Zstd perf.data compression/decompression :
--- start ---
Collecting compressed record file:
500+0 records in
500+0 records out
256000 bytes (256 kB, 250 KiB) copied, 0.00615638 s, 41.6 MB/s
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.004 MB /tmp/perf.data.X3M,
compressed (original 0.002 MB, ratio is 3.609) ]
Checking compressed events stats:
# compressed : Zstd, level = 1, ratio = 4
COMPRESSED events: 1
2ELIFREPh---- end ----
Zstd perf.data compression/decompression: Ok
[root@t35lp46 perf]#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200729135314.91281-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Following the previous change that rename egroup to metric, there's no
reason to call the list 'group_list' anymore, renaming it to
metric_list.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-20-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Renaming struct egroup to metric, because it seems to make more sense.
Plus renaming all the variables that hold egroup to appropriate names.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-19-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding test for metric group plus compute_metric_group function to get
metrics values within the group.
Committer notes:
Fixed this;
tests/parse-metric.c:327:7: error: missing field 'val' initializer [-Werror,-Wmissing-field-initializers]
{ 0 },
^
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-18-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So far compute_single function relies on the fact, that there's only
single metric defined within evlist in all tests. In following patch we
will add test for metric group, so we need to be able to compute metric
by given name.
Adding the name argument to compute_single and iterating evlist and
evsel's expression to find the given metric.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-17-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Keeping the stack of nested metrics via 'struct expr_id' objects
and checking if we are in recursion via already processed metric.
The stack is implemented as static array within the struct egroup
with 100 entries, which should be enough nesting depth for any
metric we have or plan to have at the moment.
Adding test that simulates the recursion and checks we can
detect it.
Committer notes:
Bumped RECURSION_ID_MAX to 1000 as per Jiri's reply to Paul Clark on the
patch series e-mail discussion.
Fixed these:
tests/parse-metric.c:308:7: error: missing field 'val' initializer [-Werror,-Wmissing-field-initializers]
{ 0 },
^
util/metricgroup.c:924:28: error: missing field 'parent' initializer [-Werror,-Wmissing-field-initializers]
struct expr_ids ids = { 0 };
^
util/metricgroup.c:924:26: error: suggest braces around initialization of subobject [-Werror,-Wmissing-braces]
struct expr_ids ids = { 0 };
^
{}
util/metricgroup.c:924:26: error: suggest braces around initialization of subobject [-Werror,-Wmissing-braces]
struct expr_ids ids = { 0 };
^
{}
util/metricgroup.c:924:28: error: missing field 'cnt' initializer [-Werror,-Wmissing-field-initializers]
struct expr_ids ids = { 0 };
^
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-16-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding test that compute DCache_L2 metrics with other related metrics in it.
Committer notes:
Fixed up this:
tests/parse-metric.c:285:7: error: missing field 'val' initializer [-Werror,-Wmissing-field-initializers]
{ 0 },
^
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-15-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding test that compute metric with other metrics in it.
cache_miss_cycles = metric:dcache_miss_cpi + metric:icache_miss_cycles
Committer notes:
Fixed up initializer to cope with:
tests/parse-metric.c:242:7: error: missing field 'val' initializer [-Werror,-Wmissing-field-initializers]
{ 0 },
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-14-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no need to iterate the whole list of groups, when adding new
events. The currently created groups are the ones we want to add.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-13-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding computation (expr__parse call) of referenced metric at
the point when it needs to be resolved during the parent metric
computation.
Once the inner metric is computed, the result is stored and
used if there's another usage of that metric.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-12-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding referenced metrics to the parsing context so they can be resolved
during the metric processing.
Adding expr__add_ref function to store referenced metrics into parse
context.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-11-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add referenced metrics into struct metric_expr object, so they are
accessible when computing the metric.
Storing just name and expression itself, so the metric can be resolved
and computed.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-10-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Collecting referenced metrics in struct metric_ref_node object,
so we can process them later on.
The change will parse nested metric names out of expression and
'resolve' them.
All referenced metrics are dissolved into one context, meaning all
nested metrics events and added to the parent context.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-9-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Renaming __metricgroup__add_metric to __add_metric to fit in the current
function names.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-8-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Decouple metric adding logging into add_metric function,
so it can be used from other places in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-7-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding following macros to iterate events and metric:
map_for_each_event(__pe, __idx, __map)
- iterates over all pmu_events_map events
map_for_each_metric(__pe, __idx, __map, __metric)
- iterates over all metrics that match __metric argument
and use it in metricgroup__add_metric function. Macros will be be used
from other places in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding expr__del_id function to remove ID from hashmap. It will save us
few lines in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Changing expr__get_id to use and return struct expr_id_data
pointer as value for the ID. This way we can access data other
than value for given ID in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add the expr__add_id() function to data for ID with zero value, which is
used when scanning the expression for IDs.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo found that we don't release value data in case the hashmap__set
fails. Releasing it in case of an error.
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200719181320.785305-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Test that a command line option doesn't override the period set on a
libpfm4 event.
Without libpfm4 test passes as unsupported.
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200728085734.609930-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jin Yao reported issue with possible conflict between raw events and
term values in pmu event syntax.
Currently following syntax is resolved as raw event with 0xead value:
uncore_imc_free_running/read/
instead of using 'read' term from uncore_imc_free_running pmu, because
'read' is correct raw event syntax with 0xead value.
To solve this issue we do following:
- check existing terms during rXXXX syntax processing
and make them priority in case of conflict
- allow pmu/r0x1234/ syntax to be able to specify conflicting
raw event (implemented in previous patch)
Also add automated tests for this and perf_pmu__parse_cleanup call to
parse_events_terms, so the test gets properly cleaned up.
Fixes: 3a6c51e4d6 ("perf parser: Add support to specify rXXX event with pmu")
Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200726075244.1191481-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support to specify raw event with 'r0<HEX>' syntax within pmu term
syntax like:
-e cpu/r0xdead/
It will be used to specify raw events in cases where they conflict with
real pmu terms, like 'read', which is valid raw event syntax, but also a
possible pmu term name as reported by Jin Yao.
Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200725121959.1181869-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
- auxtrace_record__init() is called only once, so there is no point in
using a static variable to cache the results of
find_all_arm_spe_pmus(), make it local and free the results after use.
- Another reason is, even though SPE is micro-architecture dependent,
but so far it only supports "statistical-profiling-extension-v1" and
we have no chance to use multiple SPE's PMU events in Perf command.
So remove the useless check code to make it clear.
Signed-off-by: Wei Li <liwei391@huawei.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20200724071111.35593-3-liwei391@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When recording with cache-misses and arm_spe_x event, I found that it
will just fail without showing any error info if i put cache-misses
after 'arm_spe_x' event.
[root@localhost 0620]# perf record -e cache-misses \
-e arm_spe_0/ts_enable=1,pct_enable=1,pa_enable=1,load_filter=1,jitter=1,store_filter=1,min_latency=0/ sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.067 MB perf.data ]
[root@localhost 0620]#
[root@localhost 0620]# perf record -e arm_spe_0/ts_enable=1,pct_enable=1,pa_enable=1,load_filter=1,jitter=1,store_filter=1,min_latency=0/ \
-e cache-misses sleep 1
[root@localhost 0620]#
The current code can only work if the only event to be traced is an
'arm_spe_x', or if it is the last event to be specified. Otherwise the
last event type will be checked against all the arm_spe_pmus[i]->types,
none will match and an out of bound 'i' index will be used in
arm_spe_recording_init().
We don't support concurrent multiple arm_spe_x events currently, that
is checked in arm_spe_recording_options(), and it will show the relevant
info. So add the check and record of the first found 'arm_spe_pmu' to
fix this issue here.
Fixes: ffd3d18c20 ("perf tools: Add ARM Statistical Profiling Extensions (SPE) support")
Signed-off-by: Wei Li <liwei391@huawei.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20200724071111.35593-2-liwei391@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The usefulness of having a standard way of testing syscall performance
has come up from time to time[0]. Furthermore, some of our testing
machinery (such as 'mmtests') already makes use of a simplified version
of the microbenchmark. This patch mainly takes the same idea to measure
syscall throughput compatible with 'perf-bench' via getppid(2), yet
without any of the additional template stuff from Ingo's version (based
on numa.c). The code is identical to what mmtests uses.
[0] https://lore.kernel.org/lkml/20160201074156.GA27156@gmail.com/
Committer notes:
Add mising stdlib.h and unistd.h to get the prototypes for exit() and
getppid().
Committer testing:
$ perf bench
Usage:
perf bench [<common options>] <collection> <benchmark> [<options>]
# List of all available benchmark collections:
sched: Scheduler and IPC benchmarks
syscall: System call benchmarks
mem: Memory access benchmarks
numa: NUMA scheduling and MM benchmarks
futex: Futex stressing benchmarks
epoll: Epoll stressing benchmarks
internals: Perf-internals benchmarks
all: All benchmarks
$
$ perf bench syscall
# List of available benchmarks for collection 'syscall':
basic: Benchmark for basic getppid(2) calls
all: Run all syscall benchmarks
$ perf bench syscall basic
# Running 'syscall/basic' benchmark:
# Executed 10000000 getppid() calls
Total time: 3.679 [sec]
0.367957 usecs/op
2717708 ops/sec
$ perf bench syscall all
# Running syscall/basic benchmark...
# Executed 10000000 getppid() calls
Total time: 3.644 [sec]
0.364456 usecs/op
2743815 ops/sec
$
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20190308181747.l36zqz2avtivrr3c@linux-r8p5
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The UDP reuseport conflict was a little bit tricky.
The net-next code, via bpf-next, extracted the reuseport handling
into a helper so that the BPF sk lookup code could invoke it.
At the same time, the logic for reuseport handling of unconnected
sockets changed via commit efc6b6f6c3
which changed the logic to carry on the reuseport result into the
rest of the lookup loop if we do not return immediately.
This requires moving the reuseport_has_conns() logic into the callers.
While we are here, get rid of inline directives as they do not belong
in foo.c files.
The other changes were cases of more straightforward overlapping
modifications.
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement handling of 'enable' and 'disable' control commands coming
from control file descriptor. If poll event splits initiated timeout
interval then the reminder is calculated and still waited in the
following evlist__poll() call.
Committer testing:
The testing instructions came in the cover letter, here I'll extract the
parts that are needed to test this specific patch, so that we don't
introduce bisection regressions by testing only the patch series as a
whole:
<FILL IN THE TEST INSTRUCTIONS>
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/3cb8a826-145f-81f4-fcb2-fa20045c6957@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Extend -D,--delay option with -1 value to start monitoring with
events disabled to be enabled later by enable command provided
via control file descriptor.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/81ac633c-a844-5cfb-931c-820f6e6cbd12@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Consolidate event dispatching loops for fork, attach and system wide
monitoring use cases into common dispatch_events() function.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/8a900bd5-200a-9b0f-7154-80a2343bfd1a@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Factor out body of event handling loop for fork case reusing
handle_interval() function.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/a8ae3f8d-a30e-fd40-998a-f5ca3e98cd45@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Check for target existence in loop control statement jointly external
asynchronous 'done' signal.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/79037528-578c-af64-f06c-a644b7f5ba6a@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce handle_interval() function that factors out body of event
handling loop for attach and system wide monitoring use cases.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/73130f9e-0d0f-7391-da50-41b4bf4bf54d@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Implement functions of initialization, finalization and processing of
control command messages coming from control file descriptors.
Allocate control file descriptor as descriptor at struct pollfd object
of evsel_list for atomic poll() operation.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/62518ceb-1cc9-2aba-593b-55408d07c1bf@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
