Process synth_opts.other_events and attr.aux_output to set up for
synthesizing PEBs via Intel PT events.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190806084606.4021-6-alexander.shishkin@linux.intel.com
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
[ Fixed up libbperf clashes, i.e. some places using perf_evsel (now in libperf)
  need to use instead 'evsel' (a tools/perf only abstraction) ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add itrace option 'o' to synthesize events recorded in the AUX area due
to the use of perf record's aux-output config term.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190806084606.4021-5-alexander.shishkin@linux.intel.com
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add aux_output attribute flag to match the kernel's perf_event.h file.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190806084606.4021-4-alexander.shishkin@linux.intel.com
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It is sometimes useful to generate a snapshot when perf record exits;
I've been using a wrapper script around the workload that would do a
killall -USR2 perf when the workload exits.

This patch makes it easier and also works when perf record is attached
to a pre-existing task. A new snapshot option 'e' can be specified in
-S to enable this behavior:

root@elsewhere:~# perf record -e intel_pt// -Se sleep 1
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.085 MB perf.data ]

Co-developed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190806144101.62892-1-alexander.shishkin@linux.intel.com
[ Fixed up !HAVE_AUXTRACE_SUPPORT build in builtin-record.c, adding 2 missing __maybe_unused ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

If we link against libcap, then we can state that CAP_SYS_ADMIN is
needed, if not, fallback to telling the user it needs to be root, as was
before linking against libcap.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Link: https://lkml.kernel.org/n/tip-hhnbjdo8r67054of9zm2kxtl@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The kernel requires CAP_SYS_ADMIN instead of euid==0 to mount debugfs
for ftrace.  Make perf do the same.

Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mathieu Poirier <mathieu.poirier@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://lkml.kernel.org/r/bd8763b72ed4d58d0b42d44fbc7eb474d32e53a3.1565188228.git.ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Some of the systems I test don't have that define, provide it
conditionally since we'll use it in the kptr_restrict checks in the next
patch.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Link: https://lkml.kernel.org/n/tip-dcize2v6jjab7tds5ngz97dk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We need to add these so that we test building without all selectable
features.

Acked-by: Igor Lubashev <ilubashe@akamai.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Link: https://lkml.kernel.org/n/tip-eknnvp22elznj0cl5a39hc4v@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add utilities to help checking capabilities of the running procss.  Make
perf link with libcap, if it is available. If no libcap-dev[el],
fallback to the geteuid() == 0 test used before.

Committer notes:

  $ perf test python
  18: 'import perf' in python                               : FAILED!
  $ perf test -v python
  Couldn't bump rlimit(MEMLOCK), failures may take place when creating BPF maps, etc
  18: 'import perf' in python                               :
  --- start ---
  test child forked, pid 23288
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  ImportError: /tmp/build/perf/python/perf.so: undefined symbol: cap_get_flag
  test child finished with -1
  ---- end ----
  'import perf' in python: FAILED!
  $

This happens because differently from the perf binary generated with
this patch applied:

  $ ldd /tmp/build/perf/perf | grep libcap
  	libcap.so.2 => /lib64/libcap.so.2 (0x00007f724a4ef000)
  $

The python binding isn't linking with libcap:

  $ ldd /tmp/build/perf/python/perf.so | grep libcap
  $

So add 'cap' to the 'extra_libraries' variable in
tools/perf/util/setup.py, and rebuild:

  $ perf test python
  18: 'import perf' in python                               : Ok
  $

If we explicitely disable libcap it also continues to work:

  $ make NO_LIBCAP=1 -C tools/perf O=/tmp/build/perf install-bin
    $ ldd /tmp/build/perf/perf | grep libcap
  $ ldd /tmp/build/perf/python/perf.so | grep libcap
  $ perf test python
  18: 'import perf' in python                               : Ok
  $

Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mathieu Poirier <mathieu.poirier@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
[ split from a larger patch ]
Link: http://lkml.kernel.org/r/8a1e76cf5c7c9796d0d4d240fbaa85305298aafa.1565188228.git.ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add utilities to help checking capabilities of the running procss.  Make
perf link with libcap, if it is available. If no libcap-dev[el], assume
no capabilities.

Committer testing:

  $ make O=/tmp/build/perf -C tools/perf install-bin
  make: Entering directory '/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j8' parallel build

  Auto-detecting system features:
  <SNIP>
  ...                        libbfd: [ on  ]
  ...                        libcap: [ OFF ]
  ...                        libelf: [ on  ]
  <SNIP>
  Makefile.config:833: No libcap found, disables capability support, please install libcap-devel/libcap-dev
  <SNIP>
  $ grep libcap /tmp/build/perf/FEATURE-DUMP
  feature-libcap=0
  $ cat /tmp/build/perf/feature/test-libcap.make.output
  test-libcap.c:2:10: fatal error: sys/capability.h: No such file or directory
      2 | #include <sys/capability.h>
        |          ^~~~~~~~~~~~~~~~~~
  compilation terminated.
  $

Now install libcap-devel and try again:

  $ make O=/tmp/build/perf -C tools/perf install-bin
  make: Entering directory '/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j8' parallel build
  Warning: Kernel ABI header at 'tools/include/linux/bits.h' differs from latest version at 'include/linux/bits.h'
  diff -u tools/include/linux/bits.h include/linux/bits.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'
  diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h

  Auto-detecting system features:
  <SNIP>
  ...                        libbfd: [ on  ]
  ...                        libcap: [ on  ]
  ...                        libelf: [ on  ]
  <SNIP>>
    CC       /tmp/build/perf/jvmti/libjvmti.o
  <SNIP>>
  $ grep libcap /tmp/build/perf/FEATURE-DUMP
  feature-libcap=1
  $ cat /tmp/build/perf/feature/test-libcap.make.output
  $ ldd /tmp/build/perf/feature/test-libcap.make.bin
  ldd: /tmp/build/perf/feature/test-libcap.make.bin: No such file or directory
  $ ldd /tmp/build/perf/feature/test-libcap.bin
  	linux-vdso.so.1 (0x00007ffc35bfe000)
  	libcap.so.2 => /lib64/libcap.so.2 (0x00007ff9c62ff000)
  	libc.so.6 => /lib64/libc.so.6 (0x00007ff9c6139000)
  	/lib64/ld-linux-x86-64.so.2 (0x00007ff9c6326000)
  $

Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
[ split from a larger patch ]
Link: http://lkml.kernel.org/r/8a1e76cf5c7c9796d0d4d240fbaa85305298aafa.1565188228.git.ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

And link them, i.e. find the hist entries in the non-leader events and
link them to the ones in the leader.

This should be the same thing already done for the 'perf report' case,
but now we do it periodically.

With this in place we get percentages in from the second overhead column
on, not just on the first (the leader).

Try it using:

  perf top --stdio -e '{cycles,instructions}'

You should see something like:

   PerfTop:   20776 irqs/sec  kernel:68.7%  exact:  0.0% lost: 0/0 drop: 0/0 [cycles],  (all, 8 CPUs)
  ---------------------------------------------------------------------------------------------------

     4.44%   0.44%  [kernel]                 [k] do_syscall_64
     2.27%   0.17%  [kernel]                 [k] entry_SYSCALL_64
     1.73%   0.27%  [kernel]                 [k] syscall_return_via_sysret
     1.60%   0.91%  [kernel]                 [k] _raw_spin_lock_irqsave
     1.45%   3.53%  libglib-2.0.so.0.6000.4  [.] g_string_insert_unichar
     1.39%   0.21%  [kernel]                 [k] copy_user_enhanced_fast_string
     1.26%   1.15%  [kernel]                 [k] psi_task_change
     1.16%   0.14%  libpixman-1.so.0.38.0    [.] 0x000000000006f403
     1.00%   0.32%  [kernel]                 [k] __sched_text_start
     0.97%   2.11%  [kernel]                 [k] n_tty_write
     0.96%   0.04%  [kernel]                 [k] queued_spin_lock_slowpath
     0.93%   0.88%  [kernel]                 [k] menu_select
     0.87%   0.14%  [kernel]                 [k] try_to_wake_up
     0.77%   0.10%  libpixman-1.so.0.38.0    [.] 0x000000000006f40b
     0.73%   0.09%  libpixman-1.so.0.38.0    [.] 0x000000000006f413
     0.69%   0.48%  libc-2.29.so             [.] __memmove_avx_unaligned_erms
     0.68%   0.29%  [kernel]                 [k] _raw_spin_lock_irq
     0.61%   0.04%  libpixman-1.so.0.38.0    [.] 0x000000000006f423
     0.60%   0.37%  [kernel]                 [k] native_sched_clock
     0.57%   0.23%  [kernel]                 [k] do_idle
     0.57%   0.23%  [kernel]                 [k] __fget
     0.56%   0.30%  [kernel]                 [k] __switch_to_asm
     0.56%   0.00%  libc-2.29.so             [.] __memset_avx2_erms
     0.52%   0.32%  [kernel]                 [k] _raw_spin_lock
     0.49%   0.24%  [kernel]                 [k] n_tty_poll
     0.49%   0.54%  libglib-2.0.so.0.6000.4  [.] g_mutex_lock
     0.48%   0.62%  [kernel]                 [k] _raw_spin_unlock_irqrestore
     0.47%   0.27%  [kernel]                 [k] __switch_to
     0.47%   0.25%  [kernel]                 [k] pick_next_task_fair
     0.45%   0.17%  [kernel]                 [k] filldir64
     0.40%   0.16%  [kernel]                 [k] update_rq_clock
     0.39%   0.19%  [kernel]                 [k] enqueue_task_fair
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-uw8cjeifxvjpkjp6x2iil0ar@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When he have an event group we have multiple struct hist instances, one
per evsel, and in each of these hists we may have hist_entries that
point to the same thing being observed, say a symbol, i.e. if we're
looking at instructions and cycles, then we'll have one hist_entry in
the "instructions" evsel and another in the "cycles" evsel.

We need to link those to then show one column for each. When we're
looking at some other pair of events, say instructions and cache misses,
we may have just the "instructions" hist entry and not one for "cache
misses", as instructions not necessarily generate cache misses, as the
logic expects one hist_entry per evsel, we end up adding "dummy"
hist_entries.

This is enough for 'perf report', that does this matching operation
(hists__match()) just once after processing all events, but for 'perf
top', we do this at each refresh, so we may finally find events matching
and then we need to trow away the dummies and link with the real events.

So if we find a match, traverse the link of matches and trow away
dummies for that hists.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-dwvtjqqifsbsczeb35q6mqkk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

'perf trace' reports the segmentation fault as below on Arm64:

  # perf trace -e string -e augmented_raw_syscalls.c
  LLVM: dumping tools/perf/examples/bpf/augmented_raw_syscalls.o
  perf: Segmentation fault
  Obtained 12 stack frames.
  perf(sighandler_dump_stack+0x47) [0xaaaaac96ac87]
  linux-vdso.so.1(+0x5b7) [0xffffadbeb5b7]
  /lib/aarch64-linux-gnu/libc.so.6(strlen+0x10) [0xfffface7d5d0]
  /lib/aarch64-linux-gnu/libc.so.6(_IO_vfprintf+0x1ac7) [0xfffface49f97]
  /lib/aarch64-linux-gnu/libc.so.6(__vsnprintf_chk+0xc7) [0xffffacedfbe7]
  perf(scnprintf+0x97) [0xaaaaac9ca3ff]
  perf(+0x997bb) [0xaaaaac8e37bb]
  perf(cmd_trace+0x28e7) [0xaaaaac8ec09f]
  perf(+0xd4a13) [0xaaaaac91ea13]
  perf(main+0x62f) [0xaaaaac8a147f]
  /lib/aarch64-linux-gnu/libc.so.6(__libc_start_main+0xe3) [0xfffface22d23]
  perf(+0x57723) [0xaaaaac8a1723]
  Segmentation fault

This issue is introduced by commit 30a910d7

 ("perf trace:
Preallocate the syscall table"), it allocates trace->syscalls.table[]
array and the element count is 'trace->sctbl->syscalls.nr_entries'; but
on Arm64, the system call number is not continuously used; e.g. the
syscall maximum id is 436 but the real entries is only 281.

So the table is allocated with 'nr_entries' as the element count, but it
accesses the table with the syscall id, which might be out of the bound
of the array and cause the segmentation fault.

This patch allocates trace->syscalls.table[] with the element count is
'trace->sctbl->syscalls.max_id + 1', this allows any id to access the
table without out of the bound.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Fixes: 30a910d7

 ("perf trace: Preallocate the syscall table")
Link: http://lkml.kernel.org/r/20190809104752.27338-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When we have multiple events in a group we link hist_entries in the
non-leader evsel hists to the one in the leader that points to the same
sorting criteria, in hists__match().

For 'perf report' we do this just once and then print the results, but
for 'perf top' we need to look if this was already done in the previous
refresh of the screen, so check for that and don't try to link again.

This is part of having 'perf top' using the hists browser for showing
multiple events in multiple columns.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-iwvb37rgb7upswhruwpcdnhw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When we want to attach just to the thread that updates the display it
helps having its COMM stand out, so change it from the default "perf" to
"perf-top-UI".

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-5w0hmlk3zfvysxvpsh763k9w@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add a Intel event file for perf.

Signed-off-by: Haiyan Song <haiyanx.song@intel.com>
Reviewed-by: Kan Liang <kan.liang@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: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/8859095e-5b02-d6b7-fbdc-3f42b714bae0@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

These paths point to the wrong location but still work because they get
picked up by a -I flag that happens to direct to the correct file. Fix
paths to lead to the actual file location without help from include
flags.

Signed-off-by: Luke Mujica <lukemujica@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20190719202253.220261-1-lukemujica@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To get the expected output we have to ignore whatever changes the user
has in its ~/.perfconfig file, so set PERF_CONFIG to /dev/null to
achieve that.

Before:

  # egrep 'trace|show_' ~/.perfconfig
  [trace]
  	show_zeros = yes
  	show_duration = no
  	show_timestamp = no
  	show_arg_names = no
  	show_prefix = yes
  # echo $PERF_CONFIG

  # perf test "trace + vfs_getname"
  70: Check open filename arg using perf trace + vfs_getname: FAILED!
  # export PERF_CONFIG=/dev/null
  # perf test "trace + vfs_getname"
  70: Check open filename arg using perf trace + vfs_getname: Ok
  #

After:

  # egrep 'trace|show_' ~/.perfconfig
  [trace]
  	show_zeros = yes
  	show_duration = no
  	show_timestamp = no
  	show_arg_names = no
  	show_prefix = yes
  # echo $PERF_CONFIG

  # perf test "trace + vfs_getname"
  70: Check open filename arg using perf trace + vfs_getname: Ok
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: https://lkml.kernel.org/n/tip-3up27pexg5i3exuzqrvt4m8u@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

There was a provision for setting this variable, but not the
getenv("PERF_CONFIG") call to set it, as this was fixed in the previous
cset, document that it can be used to ask for using an alternative
.perfconfig file or to disable reading whatever file exists in the
system or home directory, i.e. using:

  export PERF_CONFIG=/dev/null

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: https://lkml.kernel.org/n/tip-0u4o967hsk7j0o50zp9ctn89@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We had this comment in Documentation/perf_counter/config.c, i.e. since
when we got this from the git sources, but never really did that
getenv("PERF_CONFIG"), do it now as I need to disable whatever
~/.perfconfig root has so that tests parsing tool output are done for
the expected default output or that we specify an alternate config file
that when read will make the tools produce expected output.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Fixes: 07800601

 ("perf_counter tools: add in basic glue from Git")
Link: https://lkml.kernel.org/n/tip-jo209zac9rut0dz1rqvbdlgm@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Vince reported that when fuzzing the userland perf tool with a bogus
perf.data file he got into a infinite loop in 'perf report'.

Changing the return of fetch_mmaped_event() to ERR_PTR(-EINVAL) for that
case gets us out of that infinite loop.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726211415.GE24867@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To get closer to upstream and check if we need to sync more UAPI
headers, pick up fixes for libbpf that prevent perf's container tests
from completing successfuly, etc.

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

Pull dax fixes from Dan Williams:
 "A filesystem-dax and device-dax fix for v5.3.

  The filesystem-dax fix is tagged for stable as the implementation has
  been mistakenly throwing away all cow pages on any truncate or hole
  punch operation as part of the solution to coordinate device-dma vs
  truncate to dax pages.

  The device-dax change fixes up a regression this cycle from the
  introduction of a common 'internal per-cpu-ref' implementation.

  Summary:

   - Fix dax_layout_busy_page() to not discard private cow pages of
     fs/dax private mappings.

   - Update the memremap_pages core to properly cleanup on behalf of
     internal reference-count users like device-dax"

* tag 'dax-fixes-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  mm/memremap: Fix reuse of pgmap instances with internal references
  dax: dax_layout_busy_page() should not unmap cow pages

Pull NTB fix from Jon Mason:
 "Bug fix for NTB MSI kernel compile warning"

* tag 'ntb-5.3-bugfixes' of git://github.com/jonmason/ntb:
  NTB/msi: remove incorrect MODULE defines

Pull RISC-V updates from Paul Walmsley:
 "A few minor RISC-V updates for v5.3-rc4:

   - Remove __udivdi3() from the 32-bit Linux port, converting the only
     upstream user to use do_div(), per Linux policy

   - Convert the RISC-V standard clocksource away from per-cpu data
     structures, since only one is used by Linux, even on a multi-CPU
     system

   - A set of DT binding updates that remove an obsolete text binding in
     favor of a YAML binding, fix a bogus compatible string in the
     schema (thus fixing a "make dtbs_check" warning), and clarifies the
     future values expected in one of the RISC-V CPU properties"

* tag 'riscv/for-v5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  dt-bindings: riscv: fix the schema compatible string for the HiFive Unleashed board
  dt-bindings: riscv: remove obsolete cpus.txt
  RISC-V: Remove udivdi3
  riscv: delay: use do_div() instead of __udivdi3()
  dt-bindings: Update the riscv,isa string description
  RISC-V: Remove per cpu clocksource

Pull x86 fixes from Thomas Gleixner:
 "A few fixes for x86:

   - Don't reset the carefully adjusted build flags for the purgatory
     and remove the unwanted flags instead. The 'reset all' approach led
     to build fails under certain circumstances.

   - Unbreak CLANG build of the purgatory by avoiding the builtin
     memcpy/memset implementations.

   - Address missing prototype warnings by including the proper header

   - Fix yet more fall-through issues"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/lib/cpu: Address missing prototypes warning
  x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS
  x86/purgatory: Do not use __builtin_memcpy and __builtin_memset
  x86: mtrr: cyrix: Mark expected switch fall-through
  x86/ptrace: Mark expected switch fall-through

Pull perf tooling fixes from Thomas Gleixner:
 "Perf tooling fixes all over the place:

   - Fix the selection of the main thread COMM in db-export

   - Fix the disassemmbly display for BPF in annotate

   - Fix cpumap mask setup in perf ftrace when only one CPU is present

   - Add the missing 'cpu_clk_unhalted.core' event

   - Fix CPU 0 bindings in NUMA benchmarks

   - Fix the module size calculations for s390

   - Handle the gap between kernel end and module start on s390
     correctly

   - Build and typo fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf pmu-events: Fix missing "cpu_clk_unhalted.core" event
  perf annotate: Fix s390 gap between kernel end and module start
  perf record: Fix module size on s390
  perf tools: Fix include paths in ui directory
  perf tools: Fix a typo in a variable name in the Documentation Makefile
  perf cpumap: Fix writing to illegal memory in handling cpumap mask
  perf ftrace: Fix failure to set cpumask when only one cpu is present
  perf db-export: Fix thread__exec_comm()
  perf annotate: Fix printing of unaugmented disassembled instructions from BPF
  perf bench numa: Fix cpu0 binding

Pull scheduler fixes from Thomas Gleixner:
 "Three fixlets for the scheduler:

   - Avoid double bandwidth accounting in the push & pull code

   - Use a sane FIFO priority for the Pressure Stall Information (PSI)
     thread.

   - Avoid permission checks when setting the scheduler params for the
     PSI thread"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/psi: Do not require setsched permission from the trigger creator
  sched/psi: Reduce psimon FIFO priority
  sched/deadline: Fix double accounting of rq/running bw in push & pull

Pull irq fix from Thomas Gleixner:
 "A small fix for the affinity spreading code.

  It failed to handle situations where a single vector was requested
  either due to only one CPU being available or vector exhaustion
  causing only a single interrupt to be granted.

  The fix is to simply remove the requirement in the affinity spreading
  code for more than one interrupt being available"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/affinity: Create affinity mask for single vector

Pull objtool warning fix from Thomas Gleixner:
 "The recent objtool fixes/enhancements unearthed a unbalanced CLAC in
  the i915 driver.

  Chris asked me to pick the fix up and route it through"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  drm/i915: Remove redundant user_access_end() from __copy_from_user() error path

Pull gfs2 fix from Andreas Gruenbacher:
 "Fix incorrect lseek / fiemap results"

* tag 'gfs2-v5.3-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: gfs2_walk_metadata fix

A compilation -Wimplicit-fallthrough warning was enabled by commit
a035d552

 ("Makefile: Globally enable fall-through warning")

Even though clang 10.0.0 does not currently support this warning without
a patch, clang currently does not support a value for this option.

  Link: https://bugs.llvm.org/show_bug.cgi?id=39382

The gcc default for this warning is 3 so removing the =3 has no effect
for gcc and enables the warning for patched versions of clang.

Also remove the =3 from an existing use in a parisc Makefile:
arch/parisc/math-emu/Makefile

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-and-tested-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull char/misc driver fixes Greg KH:
 "Here are some small char/misc driver fixes for 5.3-rc4.

  Two of these are for the habanalabs driver for issues found when
  running on a big-endian system (are they still alive?) The others are
  tiny fixes reported by people, and a MAINTAINERS update about the
  location of the fpga development tree.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  coresight: Fix DEBUG_LOCKS_WARN_ON for uninitialized attribute
  MAINTAINERS: Move linux-fpga tree to new location
  nvmem: Use the same permissions for eeprom as for nvmem
  habanalabs: fix host memory polling in BE architecture
  habanalabs: fix F/W download in BE architecture

Pull driver core fixes from Greg KH:
 "Here are two small fixes for some driver core issues that have been
  reported. There is also a kernfs "fix" here, which was then reverted
  because it was found to cause problems in linux-next.

  The driver core fixes both resolve reported issues, one with gpioint
  stuff that showed up in 5.3-rc1, and the other finally (and hopefully)
  resolves a very long standing race when removing glue directories.
  It's nice to get that issue finally resolved and the developers
  involved should be applauded for the persistence it took to get this
  patch finally accepted.

  All of these have been in linux-next for a while with no reported
  issues. Well, the one reported issue, hence the revert :)"

* tag 'driver-core-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  Revert "kernfs: fix memleak in kernel_ops_readdir()"
  kernfs: fix memleak in kernel_ops_readdir()
  driver core: Fix use-after-free and double free on glue directory
  driver core: platform: return -ENXIO for missing GpioInt

Pull tty fix from Greg KH:
 "Here is a single tty kgdb fix for 5.3-rc4.

  It fixes an annoying log message that has caused kdb to become
  useless. It's another fallout from commit ddde3c18 ("vt: More
  locking checks") which tries to enforce locking checks more strictly
  in the tty layer, unfortunatly when kdb is stopped, there's no need
  for locks :)

  This patch has been linux-next for a while with no reported issues"

* tag 'tty-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  kgdboc: disable the console lock when in kgdb

Pull staging / IIO driver fixes from Greg KH:
 "Here are some small staging and IIO driver fixes for 5.3-rc4.

  Nothing major, just resolutions for a number of small reported issues,
  full details in the shortlog.

  All have been in linux-next for a while with no reported issues"

* tag 'staging-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  iio: adc: gyroadc: fix uninitialized return code
  docs: generic-counter.rst: fix broken references for ABI file
  staging: android: ion: Bail out upon SIGKILL when allocating memory.
  Staging: fbtft: Fix GPIO handling
  staging: unisys: visornic: Update the description of 'poll_for_irq()'
  staging: wilc1000: flush the workqueue before deinit the host
  staging: gasket: apex: fix copy-paste typo
  Staging: fbtft: Fix reset assertion when using gpio descriptor
  Staging: fbtft: Fix probing of gpio descriptor
  iio: imu: mpu6050: add missing available scan masks
  iio: cros_ec_accel_legacy: Fix incorrect channel setting
  IIO: Ingenic JZ47xx: Set clock divider on probe
  iio: adc: max9611: Fix misuse of GENMASK macro

Pull USB fixes from Greg KH:
 "Here are some small USB fixes for 5.3-rc4.

  The "biggest" one here is moving code from one file to another in
  order to fix a long-standing race condition with the creation of sysfs
  files for USB devices. Turns out that there are now userspace tools
  out there that are hitting this long-known bug, so it's time to fix
  them. Thankfully the tool-maker in this case fixed the issue :)

  The other patches in here are all fixes for reported issues. Now that
  syzbot knows how to fuzz USB drivers better, and is starting to now
  fuzz the userspace facing side of them at the same time, there will be
  more and more small fixes like these coming, which is a good thing.

  All of these have been in linux-next with no reported issues"

* tag 'usb-5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: setup authorized_default attributes using usb_bus_notify
  usb: iowarrior: fix deadlock on disconnect
  Revert "USB: rio500: simplify locking"
  usb: usbfs: fix double-free of usb memory upon submiturb error
  usb: yurex: Fix use-after-free in yurex_delete
  usb: typec: tcpm: Ignore unsupported/unknown alternate mode requests
  xhci: Fix NULL pointer dereference at endpoint zero reset.
  usb: host: xhci-rcar: Fix timeout in xhci_suspend()
  usb: typec: ucsi: ccg: Fix uninitilized symbol error
  usb: typec: tcpm: remove tcpm dir if no children
  usb: typec: tcpm: free log buf memory when remove debug file
  usb: typec: tcpm: Add NULL check before dereferencing config

Pull pin control fixes from Linus Walleij:

 - Delay acquisition of regmaps in the Aspeed G5 driver.

 - Make a symbol static to reduce compiler noise.

* tag 'pinctrl-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: aspeed: Make aspeed_pinmux_ips static
  pinctrl: aspeed-g5: Delay acquisition of regmaps

Pull powerpc fix from Michael Ellerman:
 "Just one fix, a revert of a commit that was meant to be a minor
  improvement to some inline asm, but ended up having no real benefit
  with GCC and broke booting 32-bit machines when using Clang.

  Thanks to: Arnd Bergmann, Christophe Leroy, Nathan Chancellor, Nick
  Desaulniers, Segher Boessenkool"

* tag 'powerpc-5.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  Revert "powerpc: slightly improve cache helpers"