The NMI watchdog status is required for metric group constraint
examination.  Factor out sysctl__nmi_watchdog_enabled() to retrieve the
NMI watchdog status.

Users may count more than one metric group each time. If so, the NMI
watchdog status may be retrieved several times. To reduce the overhead,
cache the NMI watchdog status.

Replace the NMI watchdog status checking in print_footer() by
sysctl__nmi_watchdog_enabled().
Suggested-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/1582581564-184429-4-git-send-email-kan.liang@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Factor out metricgroup__add_metric_weak_group() which add metrics into a
weak group. The change can improve code readability. Because following
patch will introduce a function which add standalone metrics.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/1582581564-184429-3-git-send-email-kan.liang@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

A new field "MetricConstraint" is introduced in JSON event list.

Extend jevents to parse the field and save the value in
metric_constraint.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/1582581564-184429-2-git-send-email-kan.liang@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add support for new deflate counters:

- Counter 247: cycles CPU spent obtaining access to Deflate unit
- Counter 252: cycles CPU is using Deflate unit
- Counter 264: Increments by one for every DEFLATE CONVERSION CALL
	    instruction executed.
- Counter 265: Increments by one for every DEFLATE CONVERSION CALL
	    instruction executed that ended in Condition Codes
	    0, 1 or 2.

Also adjust the some crypto counter description to latest documentation.
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: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200310142937.32045-1-tmricht@linux.ibm.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It would be nice to print the block percents with colors.

This patch supports the 'Sampled Cycles%' and 'Avg Cycles%' printed in
colors.

For example,

perf record -b ...
perf report --total-cycles or perf report --total-cycles --stdio

percent > 5%, colored in red
percent > 0.5%, colored in green
percent < 0.5%, default color
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.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/20200202141655.32053-5-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Currently we use a predefined array to set the block info output
formats, it's fixed and inflexible.

This patch adds two parameters "block_hpps" and "nr_hpps" in
block_info__create_report and other static functions, in order to let
user decide which columns to report and with specified report ordering.
It should be more flexible.

Buffers will be allocated to contain the new fmts, of course, we need to
release them before perf exits.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.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/20200202141655.32053-4-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

'perf diff' uses block_pair_cmp() to compare two blocks. But
block_info__cmp() has the similar functionality and it's a bit more
complete.

This patch removes block_pair_cmp() and uses __block_info__cmp()
instead. __block_info__cmp() is wrapped by block_info__cmp() and it
doesn't receives a perf_hpp_fmt parameter.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.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/20200202141655.32053-3-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Commit 60414418 ("perf block: Cleanup and refactor block info
functions") introduces block_info__cmp(), which compares two blocks.

But the issues are:

1. It should return the strcmp cmp value only if it's not 0.

2. When symbol names are matched, we need to compare the addresses
   of blocks further. But it wrongly uses the symbol addresses for
   comparison.

3. If the syms are both NULL, we can't consider these two blocks are
   matched.

This patch fixes above 3 issues.

Fixes: 60414418 ("perf block: Cleanup and refactor block info functions")
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.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/20200202141655.32053-2-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To match the error value of the expr__find_other function, so all
exported expr functions return the same values:
0 on success, -1 on error.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200228093616.67125-6-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Now that we have a flex parser we don't need to update the parsed string
pointer, so the interface can just be passed the pointer to the
expression instead of a pointer to pointer.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200228093616.67125-5-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We have metrics that define more than 15 variables, like
Branch_Misprediction_Cost. Increasing the allowed variables count to 20.

As Andy pointed out, we can't go too high in here, because some of the
code has O(n^2) complexity (already_seen) and we might want to do some
other changes (like using hash tables) before increasing the maximum
even more.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200228093616.67125-4-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Adding expr flex code instead of the manual parser code. So it's easily
extensible in upcoming changes.

The new flex code is in flex.l object and gets compiled like all the
other flexers we use.  It's defined as flex reentrant parser.

It's used by both expr__parse and expr__find_other interfaces by
separating the starting point.

There's no intended change of functionality ;-) the test expr is
passing.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200228093616.67125-3-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add generic expr code into new expr.c object.

The expr.c object will be mainly used in following change that will get
rid of the manual flex code,
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@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: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200228093616.67125-2-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf.data may be generated by a newer version of perf tool, which
support new input bits in attr, e.g. new bit for branch_sample_type.

The perf.data may be parsed by an older version of perf tool later.  The
old perf tool may parse the perf.data incorrectly. There is no warning
message for this case.

Current perf header never check for unknown input bits in attr.

When read the event desc from header, check the stored event attr.  The
reserved bits, sample type, read format and branch sample type will be
checked.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lkml.kernel.org/r/20200228163011.19358-4-kan.liang@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

A new branch sample type PERF_SAMPLE_BRANCH_HW_INDEX has been introduced
in latest kernel.

Enable HW_INDEX by default in LBR call stack mode.

If kernel doesn't support the sample type, switching it off.

Add HW_INDEX in attr_fprintf as well. User can check whether the branch
sample type is set via debug information or header.

Committer testing:

First collect some samples with LBR callchains, system wide, for a few
seconds:

  # perf record --call-graph lbr -a sleep 5
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.625 MB perf.data (224 samples) ]
  #

Now lets use 'perf evlist -v' to look at the branch_sample_type:

  # perf evlist -v
  cycles: size: 120, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|BRANCH_STACK, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1, branch_sample_type: USER|CALL_STACK|NO_FLAGS|NO_CYCLES|HW_INDEX
  #

So the machine has the kernel feature, and it was correctly added to
perf_event_attr.branch_sample_type, for the default 'cycles' event.

If we do it in another machine, where the kernel lacks the HW_INDEX
feature, we get:

  # perf record --call-graph lbr -a sleep 2s
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 1.690 MB perf.data (499 samples) ]
  # perf evlist -v
  cycles: size: 120, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|BRANCH_STACK, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1, branch_sample_type: USER|CALL_STACK|NO_FLAGS|NO_CYCLES
  #

No HW_INDEX in attr.branch_sample_type.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200228163011.19358-3-kan.liang@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The low level index of raw branch records for the most recent branch can
be recorded in a sample with PERF_SAMPLE_BRANCH_HW_INDEX
branch_sample_type. Extend struct branch_stack to support it.

However, if the PERF_SAMPLE_BRANCH_HW_INDEX is not applied, only nr and
entries[] will be output by kernel. The pointer of entries[] could be
wrong, since the output format is different with new struct
branch_stack.  Add a variable no_hw_idx in struct perf_sample to
indicate whether the hw_idx is output.  Add get_branch_entry() to return
corresponding pointer of entries[0].

To make dummy branch sample consistent as new branch sample, add hw_idx
in struct dummy_branch_stack for cs-etm and intel-pt.

Apply the new struct branch_stack for synthetic events as well.

Extend test case sample-parsing to support new struct branch_stack.

Committer notes:

Renamed get_branch_entries() to perf_sample__branch_entries() to have
proper namespacing and pave the way for this to be moved to libperf,
eventually.

Add 'static' to that inline as it is in a header.

Add 'hw_idx' to 'struct dummy_branch_stack' in cs-etm.c to fix the build
on arm64.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200228163011.19358-2-kan.liang@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To get the changes in:

  bbfd5e4f ("perf/core: Add new branch sample type for HW index of raw branch records")

This silences this perf tools build warning:

  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

This update is a prerequisite to adding support for the HW index of raw
branch records.
Acked-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200304134902.GB12612@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

If the precision of print_event_time() is zero or greater than the
timestamp, it uses a different format. But that format had an extra new
line at the end, and caused the output to not look right:

cpus=2
           sleep-3946  [001]111264306005
: function:             inotify_inode_queue_event
           sleep-3946  [001]111264307158
: function:             __fsnotify_parent
           sleep-3946  [001]111264307637
: function:             inotify_dentry_parent_queue_event
           sleep-3946  [001]111264307989
: function:             fsnotify
           sleep-3946  [001]111264308401
: function:             audit_syscall_exit

Fixes: 38847db9 ("libtraceevent, perf tools: Changes in tep_print_event_* APIs")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200303231852.6ab6882f@oasis.local.homeSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Current libperf man pages mention file counting.c "coming with libperf package",
however, the file is missing. Add the file then.

Fixes: 81de3bf3 ("libperf: Add man pages")
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LPU-Reference: 20200227194424.28210-1-mpetlan@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The 'nr_jumps' field in 'struct annotation' is not used since it's
inception in commit 2402e4a9 ("perf annotate browser: Show 'jumpy'
functions").  Get rid of it.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200204045233.474937-7-ravi.bangoria@linux.ibm.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To help in debugging, add this extra message:

  detect_kbuild_dir: Couldn't find "/lib/modules/5.4.20-200.fc31.x86_64/build/include/generated/autoconf.h", missing kernel-devel package?.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We have supported the event modifier "percore" which sums up the event
counts for all hardware threads in a core and show the counts per core.

For example,

 # perf stat -e cpu/event=cpu-cycles,percore/ -a -A -- sleep 1

  Performance counter stats for 'system wide':

 S0-D0-C0                395,072      cpu/event=cpu-cycles,percore/
 S0-D0-C1                851,248      cpu/event=cpu-cycles,percore/
 S0-D0-C2                954,226      cpu/event=cpu-cycles,percore/
 S0-D0-C3              1,233,659      cpu/event=cpu-cycles,percore/

This patch provides a new option "--percore-show-thread". It is used
with event modifier "percore" together to sum up the event counts for
all hardware threads in a core but show the counts per hardware thread.

This is essentially a replacement for the any bit (which is gone in
Icelake). Per core counts are useful for some formulas, e.g. CoreIPC.
The original percore version was inconvenient to post process. This
variant matches the output of the any bit.

With this patch, for example,

 # perf stat -e cpu/event=cpu-cycles,percore/ -a -A --percore-show-thread  -- sleep 1

  Performance counter stats for 'system wide':

 CPU0               2,453,061      cpu/event=cpu-cycles,percore/
 CPU1               1,823,921      cpu/event=cpu-cycles,percore/
 CPU2               1,383,166      cpu/event=cpu-cycles,percore/
 CPU3               1,102,652      cpu/event=cpu-cycles,percore/
 CPU4               2,453,061      cpu/event=cpu-cycles,percore/
 CPU5               1,823,921      cpu/event=cpu-cycles,percore/
 CPU6               1,383,166      cpu/event=cpu-cycles,percore/
 CPU7               1,102,652      cpu/event=cpu-cycles,percore/

We can see counts are duplicated in CPU pairs (CPU0/CPU4, CPU1/CPU5,
CPU2/CPU6, CPU3/CPU7).

The interval mode also works. For example,

 # perf stat -e cpu/event=cpu-cycles,percore/ -a -A --percore-show-thread  -I 1000
 #           time CPU                    counts unit events
      1.000425421 CPU0                 925,032      cpu/event=cpu-cycles,percore/
      1.000425421 CPU1                 430,202      cpu/event=cpu-cycles,percore/
      1.000425421 CPU2                 436,843      cpu/event=cpu-cycles,percore/
      1.000425421 CPU3               1,192,504      cpu/event=cpu-cycles,percore/
      1.000425421 CPU4                 925,032      cpu/event=cpu-cycles,percore/
      1.000425421 CPU5                 430,202      cpu/event=cpu-cycles,percore/
      1.000425421 CPU6                 436,843      cpu/event=cpu-cycles,percore/
      1.000425421 CPU7               1,192,504      cpu/event=cpu-cycles,percore/

If we offline CPU5, the result is:

 # perf stat -e cpu/event=cpu-cycles,percore/ -a -A --percore-show-thread -- sleep 1

  Performance counter stats for 'system wide':

 CPU0               2,752,148      cpu/event=cpu-cycles,percore/
 CPU1               1,009,312      cpu/event=cpu-cycles,percore/
 CPU2               2,784,072      cpu/event=cpu-cycles,percore/
 CPU3               2,427,922      cpu/event=cpu-cycles,percore/
 CPU4               2,752,148      cpu/event=cpu-cycles,percore/
 CPU6               2,784,072      cpu/event=cpu-cycles,percore/
 CPU7               2,427,922      cpu/event=cpu-cycles,percore/

        1.001416041 seconds time elapsed

 v4:
 ---
 Ravi Bangoria reports an issue in v3. Once we offline a CPU,
 the output is not correct. The issue is we should use the cpu
 idx in print_percore_thread rather than using the cpu value.

 v3:
 ---
 1. Fix the interval mode output error
 2. Use cpu value (not cpu index) in config->aggr_get_id().
 3. Refine the code according to Jiri's comments.

 v2:
 ---
 Add the explanation in change log. This is essentially a replacement
 for the any bit. No code change.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200214080452.26402-1-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Move it from tools/perf/util/cgroup.c as it can be used by other places.
Note that cgroup filesystem is different from others since it's usually
mounted separately (in v1) for each subsystem.

I just copied the code with a little modification to pass a name of
subsystem.
Suggested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200127100031.1368732-1-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To pick up fixes.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

clang warns:

  util/block-info.c:298:18: error: result of comparison against a string
  literal is unspecified (use an explicit string comparison function
  instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                          ^  ~~~~~~~~~~~~~~~
  util/block-info.c:298:51: error: result of comparison against a string
  literal is unspecified (use an explicit string comparison function
  instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                                                           ^  ~~~~~~~~~~~~~~~
  util/block-info.c:298:18: error: result of comparison against a string
  literal is unspecified (use an explicit string
  comparison function instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                          ^  ~~~~~~~~~~~~~~~
  util/block-info.c:298:51: error: result of comparison against a string
  literal is unspecified (use an explicit string comparison function
  instead) [-Werror,-Wstring-compare]
          if ((start_line != SRCLINE_UNKNOWN) && (end_line != SRCLINE_UNKNOWN)) {
                                                           ^  ~~~~~~~~~~~~~~~
  util/map.c:434:15: error: result of comparison against a string literal
  is unspecified (use an explicit string comparison function instead)
  [-Werror,-Wstring-compare]
                  if (srcline != SRCLINE_UNKNOWN)
                              ^  ~~~~~~~~~~~~~~~

Reviewer Notes:

Looks good to me. Some more context:
https://clang.llvm.org/docs/DiagnosticsReference.html#wstring-compare
The spec says:
J.1 Unspecified behavior
The following are unspecified:
.. Whether two string literals result in distinct arrays (6.4.5).
Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Keeping <john@metanate.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: clang-built-linux@googlegroups.com
Link: https://github.com/ClangBuiltLinux/linux/issues/900
Link: http://lore.kernel.org/lkml/20200223193456.25291-1-nick.desaulniers@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-urgent-for-mingo-5.6-20200303' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

perf symbols:

  Arnaldo Carvalho de Melo:

  - Don't try to find a vmlinux file when looking for kernel modules,
    fixing symbol resolution in systems with compressed kernel modules.

perf env:

  Arnaldo Carvalho de Melo:

  - Do not return pointers to local variables, fixing valid warning from
    gcc 10 for corner case that stops the build due to -Werror.

perf tests:

  Arnaldo Carvalho de Melo:

  - Make global variable static in the bp_account entry to fix build
    with gcc 10.

perf parse-events:

  Arnaldo Carvalho de Melo:

  - Use asprintf() instead of strncpy() to read tracepoint files, addressing
    compiler warning that stops the build as we use -Werror.

perf bench:

  Arnaldo Carvalho de Melo:

  - Share some global variables to fix build with gcc 10.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull cifs fixes from Steve French:
 "Five small cifs/smb3 fixes, two for stable (one for a reconnect
  problem and the other fixes a use case when renaming an open file)"

* tag '5.6-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Use #define in cifs_dbg
  cifs: fix rename() by ensuring source handle opened with DELETE bit
  cifs: add missing mount option to /proc/mounts
  cifs: fix potential mismatch of UNC paths
  cifs: don't leak -EAGAIN for stat() during reconnect

The dso->kernel value is now set to everything that is in
machine->kmaps, but that was being used to decide if vmlinux lookup is
needed, which ended up making that lookup be made for kernel modules,
that now have dso->kernel set, leading to these kinds of warnings when
running on a machine with compressed kernel modules, like fedora:31:

  [root@five ~]# perf record -F 10000 -a sleep 2
  [ perf record: Woken up 1 times to write data ]
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  lzma: fopen failed on vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux: 'No such file or directory'
  lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory'
  lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory'
  [ perf record: Captured and wrote 1.024 MB perf.data (1366 samples) ]
  [root@five ~]#

This happens when collecting the buildid, when we find samples for
kernel modules, fix it by checking if the looked up DSO is a kernel
module by other means.

Fixes: 02213cec ("perf maps: Mark module DSOs with kernel type")
Tested-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200302191007.GD10335@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Noticed with gcc 10 (fedora rawhide) that those variables were not being
declared as static, so end up with:

  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here
  make[4]: *** [/git/perf/tools/build/Makefile.build:145: /tmp/build/perf/bench/perf-in.o] Error 1

Prefix those with bench__ and add them to bench/bench.h, so that we can
share those on the tools needing to access those variables from signal
handlers.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200303155811.GD13702@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Make the code more compact by using asprintf() instead of malloc()+strncpy() which also uses
less memory and avoids these warnings with gcc 10:

    CC       /tmp/build/perf/util/cloexec.o
  In file included from /usr/include/string.h:495,
                   from util/parse-events.h:12,
                   from util/parse-events.c:18:
  In function ‘strncpy’,
      inlined from ‘tracepoint_id_to_path’ at util/parse-events.c:271:5:
  /usr/include/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ offset [275, 511] from the object at ‘sys_dirent’ is out of the bounds of referenced subobject ‘d_name’ with type ‘char[256]’ at offset 19 [-Werror=array-bounds]
    106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  In file included from /usr/include/dirent.h:61,
                   from util/parse-events.c:5:
  util/parse-events.c: In function ‘tracepoint_id_to_path’:
  /usr/include/bits/dirent.h:33:10: note: subobject ‘d_name’ declared here
     33 |     char d_name[256];  /* We must not include limits.h! */
        |          ^~~~~~
  In file included from /usr/include/string.h:495,
                   from util/parse-events.h:12,
                   from util/parse-events.c:18:
  In function ‘strncpy’,
      inlined from ‘tracepoint_id_to_path’ at util/parse-events.c:273:5:
  /usr/include/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ offset [275, 511] from the object at ‘evt_dirent’ is out of the bounds of referenced subobject ‘d_name’ with type ‘char[256]’ at offset 19 [-Werror=array-bounds]
    106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  In file included from /usr/include/dirent.h:61,
                   from util/parse-events.c:5:
  util/parse-events.c: In function ‘tracepoint_id_to_path’:
  /usr/include/bits/dirent.h:33:10: note: subobject ‘d_name’ declared here
     33 |     char d_name[256];  /* We must not include limits.h! */
        |          ^~~~~~
    CC       /tmp/build/perf/util/call-path.o

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200302145535.GA28183@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It is possible to return a pointer to a local variable when looking up
the architecture name for the running system and no normalization is
done on that value, i.e. we may end up returning the uts.machine local
variable.

While this doesn't happen on most arches, as normalization takes place,
lets fix this by making that a static variable and optimize it a bit by
not always running uname(), only the first time.

Noticed in fedora rawhide running with:

  [perfbuilder@a5ff49d6e6e4 ~]$ gcc --version
  gcc (GCC) 10.0.1 20200216 (Red Hat 10.0.1-0.8)
Reported-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To fix the build with newer gccs, that without this patch exit with:

    LD       /tmp/build/perf/tests/perf-in.o
  ld: /tmp/build/perf/tests/bp_account.o:/git/perf/tools/perf/tests/bp_account.c:22: multiple definition of `the_var'; /tmp/build/perf/tests/bp_signal.o:/git/perf/tools/perf/tests/bp_signal.c:38: first defined here
  make[4]: *** [/git/perf/tools/build/Makefile.build:145: /tmp/build/perf/tests/perf-in.o] Error 1

First noticed in fedora:rawhide/32 with:

  [perfbuilder@a5ff49d6e6e4 ~]$ gcc --version
  gcc (GCC) 10.0.1 20200216 (Red Hat 10.0.1-0.8)
Reported-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull x86 fixes from Ingo Molnar:
 "Misc fixes: a pkeys fix for a bug that triggers with weird BIOS
  settings, and two Xen PV fixes: a paravirt interface fix, and
  pagetable dumping fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix dump_pagetables with Xen PV
  x86/ioperm: Add new paravirt function update_io_bitmap()
  x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes

Pull scheduler fix from Ingo Molnar:
 "Fix a scheduler statistics bug"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix statistics for find_idlest_group()

Pull perf fixes from Ingo Molnar:
 "No kernel side changes, all tooling fixes plus two tooling cleanups
  that were committed late in the merge window alongside the perf
  annotate fixes, delayed by Arnaldo's European trip"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  perf annotate: Fix segfault with source toggle
  perf annotate: Align struct annotate_args
  perf annotate: Simplify disasm_line allocation and freeing code
  perf annotate: Remove privsize from symbol__annotate() args
  perf probe: Check return value of strlist__add() for -ENOMEM
  perf config: Document missing config options
  perf annotate: Fix perf config option description
  perf annotate: Prefer cmdline option over default config
  perf annotate: Make perf config effective
  perf config: Introduce perf_config_u8()
  perf annotate: Fix --show-nr-samples for tui/stdio2
  perf annotate: Fix --show-total-period for tui/stdio2
  perf annotate/tui: Re-render title bar after switching back from script browser
  tools headers UAPI: Update tools's copy of kvm.h headers
  tools arch x86: Sync the msr-index.h copy with the kernel sources
  perf arch powerpc: Sync powerpc syscall.tbl with the kernel sources
  perf auxtrace: Add auxtrace_record__read_finish()
  perf arm-spe: Fix endless record after being terminated
  perf cs-etm: Fix endless record after being terminated
  perf intel-bts: Fix endless record after being terminated
  ...

Pull EFI fixes from Ingo Molnar:
 "Three fixes to EFI mixed boot mode, mostly related to x86-64 vmap
  stacks activated years ago, bug-fixed recently for EFI, which had
  knock-on effects of various 1:1 mapping assumptions in mixed mode.

  There's also a READ_ONCE() fix for reading an mmap-ed EFI firmware
  data field only once, out of caution"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: READ_ONCE rng seed size before munmap
  efi/x86: Handle by-ref arguments covering multiple pages in mixed mode
  efi/x86: Remove support for EFI time and counter services in mixed mode
  efi/x86: Align GUIDs to their size in the mixed mode runtime wrapper

Pull ext4 fixes from Ted Ts'o:
 "Two more bug fixes (including a regression) for 5.6"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: potential crash on allocation error in ext4_alloc_flex_bg_array()
  jbd2: fix data races at struct journal_head

Pull KVM fixes from Paolo Bonzini:
 "More bugfixes, including a few remaining "make W=1" issues such as too
  large frame sizes on some configurations.

  On the ARM side, the compiler was messing up shadow stacks between EL1
  and EL2 code, which is easily fixed with __always_inline"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: check descriptor table exits on instruction emulation
  kvm: x86: Limit the number of "kvm: disabled by bios" messages
  KVM: x86: avoid useless copy of cpufreq policy
  KVM: allow disabling -Werror
  KVM: x86: allow compiling as non-module with W=1
  KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
  KVM: Introduce pv check helpers
  KVM: let declaration of kvm_get_running_vcpus match implementation
  KVM: SVM: allocate AVIC data structures based on kvm_amd module parameter
  arm64: Ask the compiler to __always_inline functions used by KVM at HYP
  KVM: arm64: Define our own swab32() to avoid a uapi static inline
  KVM: arm64: Ask the compiler to __always_inline functions used at HYP
  kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe()
  KVM: arm/arm64: Fix up includes for trace.h

KVM emulates UMIP on hardware that doesn't support it by setting the
'descriptor table exiting' VM-execution control and performing
instruction emulation. When running nested, this emulation is broken as
KVM refuses to emulate L2 instructions by default.

Correct this regression by allowing the emulation of descriptor table
instructions if L1 hasn't requested 'descriptor table exiting'.

Fixes: 07721fee ("KVM: nVMX: Don't emulate instructions in guest mode")
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Cc: stable@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>