Make system wide (-a) the default option if no target was specified and
one of following conditions is met:

  - there's no workload specified (current behaviour)
  - there is workload specified but all requested
    events are system wide ones

Mixed events core/uncore with workload:

  $ perf stat -e 'uncore_cbox_0/clockticks/,cycles' sleep 1

   Performance counter stats for 'sleep 1':

     <not supported>      uncore_cbox_0/clockticks/
             980,489      cycles

         1.000897406 seconds time elapsed

Uncore event with workload:

  $ perf stat -e 'uncore_cbox_0/clockticks/' sleep 1

   Performance counter stats for 'system wide':

  281,473,897,192,670      uncore_cbox_0/clockticks/

         1.000833784 seconds time elapsed

Committer note:

When testing I realized the default case for !root, i.e. no events
passed via -e, was broke by v2 of this patch, reported and after a
patch provided by Jiri it is back working:

  [acme@jouet linux]$ perf stat usleep 1

   Performance counter stats for 'usleep 1':

         0.401335      task-clock:u (msec)     #   0.297 CPUs utilized
                0      context-switches:u      #   0.000 K/sec
                0      cpu-migrations:u        #   0.000 K/sec
               48      page-faults:u           #   0.120 M/sec
          458,146      cycles:u                #   1.142 GHz
          245,113      instructions:u          #   0.54  insn per cycle
           47,991      branches:u              # 119.578 M/sec
            4,022      branch-misses:u         #   8.38% of all branches

      0.001350029 seconds time elapsed

  [acme@jouet linux]$
Suggested-and-Tested-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170227094818.GA12764@kravaSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

  $ perf test decoder
  57: x86 instruction decoder - new instructions : FAILED!
  $

  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 80 78 56 34 12 	bndstx %bnd0,0x12345678(%rax)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 85 78 56 34 12 	bndstx %bnd0,0x12345678(%rbp)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 84 01 78 56 34 12 	bndstx %bnd0,0x12345678(%rcx,%rax,1)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 84 05 78 56 34 12 	bndstx %bnd0,0x12345678(%rbp,%rax,1)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 84 08 78 56 34 12 	bndstx %bnd0,0x12345678(%rax,%rcx,1)

There is missing initialization.  It only affects the test because it is
checking 'rel' even in cases where there is no value.

Fix it.
Reported-and-Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/08c6ad07-7994-3e56-b20e-d75727ca7765@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Generalize probe event file open routine into a generic function for opening
trace files.
Signed-off-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/b580465c7a4dcd5d3b40fdf8568e6be45d0a6333.1487849577.git.naveen.n.rao@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It's convenient to use the pager when seeing many lines of result.

Note that setup_pager() should be called after perf_evlist__prepare_workload()
since they can interfere each other regarding shared stdio streams.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170224011251.14946-4-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The -a/--all-cpus and -C/--cpu option is for controlling tracing cpus.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170224011251.14946-3-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The cpu_map__snprint_mask() generates a string representation of a
cpumask bitmap.  For cpu 0 to 11, it'll return "fff".

Committer notes:

Fix compiler warning on some toolchains:

    19 fedora:24-x-ARC-uClibc: FAIL

    CC       /tmp/build/perf/util/cpumap.o
  util/cpumap.c: In function 'hex_char':
  util/cpumap.c:679:2: error: comparison is always true due to limited range of data type [-Werror=type-limits]
    if (0 <= val && val <= 9)
    ^
  cc1: all warnings being treated as errors

Applying patch from Namhyung that makes function receive an 'unsigned
char', that is what the callers are passing to this function.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170224011251.14946-2-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The -p (--pid) option enables to trace existing process by its pid.

Committer notes:

Testing it:

Using the function_graph tracer on a process that is just waiting for user
input and thus will make 'perf ftrace' sit there waiting for that, then press
any key on that mutt session and see what happens:

  # perf ftrace -t function_graph -p `pidof mutt` | head -40
  2)   1.038 us    |  switch_mm_irqs_off();
  ------------------------------------------
  2)    <idle>-0    =>   mutt-3595
  ------------------------------------------

  2)               |              finish_task_switch() {
  2)               |                smp_irq_work_interrupt() {
  2)               |                  irq_enter() {
  2)   0.180 us    |                    rcu_irq_enter();
  2)   1.248 us    |                  }
  2)               |                  __wake_up() {
  2)   0.126 us    |                    _raw_spin_lock_irqsave();
  2)               |                    __wake_up_common() {
  2)               |                      pollwake() {
  2)               |                        default_wake_function() {
  2)               |                          try_to_wake_up() {
  2)   0.662 us    |                            _raw_spin_lock_irqsave();
  2)               |                            select_task_rq_fair() {
  2)   1.719 us    |                              effective_load.isra.41();
  2)   1.343 us    |                              effective_load.isra.41();
  2)               |                              select_idle_sibling() {
  2)   0.331 us    |                                idle_cpu();
  2)   1.458 us    |                              }
  2)   8.350 us    |                            }
  2)   0.200 us    |                            _raw_spin_lock();
  2)               |                            ttwu_do_activate() {
  2)               |                              activate_task() {
  2)   0.136 us    |                                update_rq_clock.part.77();
  2)               |                                enqueue_task_fair() {
  2)               |                                  enqueue_entity() {
  2)   0.146 us    |                                    update_curr();
  2)   0.330 us    |                                    account_entity_enqueue();
  2)   0.280 us    |                                    update_cfs_shares();
  2)   0.321 us    |                                    place_entity();
  2)   0.206 us    |                                    __enqueue_entity();
  2)   6.926 us    |                                  }
  2)               |                                  enqueue_entity() {
  2)   0.105 us    |                                    update_curr();
  2)   0.175 us    |                                    account_entity_enqueue();
  2)   0.531 us    |                                    update_cfs_shares();
 #
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170224011251.14946-1-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add new sort key 'symbol_size' to allow user to sort by symbol size, or
(more usefully) display the symbol size using --fields=...,symbol_size.

Committer note:

Testing it together with the recently added -q, to remove the headers,
and using the '+' sign with -s, to add the symbol_size sort order to
the default, which is '-s/--sort comm,dso,symbol':

  # perf report -q -s +symbol_size | head -10
  10.39%  swapper       [kernel.vmlinux] [k] intel_idle               270
   3.45%  swapper       [kernel.vmlinux] [k] update_blocked_averages 1546
   2.61%  swapper       [kernel.vmlinux] [k] update_load_avg         1292
   2.36%  swapper       [kernel.vmlinux] [k] update_cfs_shares        240
   1.83%  swapper       [kernel.vmlinux] [k] __hrtimer_run_queues     606
   1.74%  swapper       [kernel.vmlinux] [k] update_cfs_rq_load_avg. 1187
   1.66%  swapper       [kernel.vmlinux] [k] apic_timer_interrupt     152
   1.60%  CPU 0/KVM     [kvm]            [k] kvm_set_msr_common      3046
   1.60%  gnome-shell   libglib-2.0.so.0 [.] g_slist_find              37
   1.46%  gnome-termina libglib-2.0.so.0 [.] g_hash_table_lookup      370
  #
Signed-off-by: NCharles Baylis <charles.baylis@linaro.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1487943176-13840-1-git-send-email-charles.baylis@linaro.org
[ Use symbol__size(), remove needless %lld + (long long) casting ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is an odd refcount use case, so add some more comments to help
understand that when it hits zero it really means that the mmap()ed area
(on a perf_event_open() returned fd) has been munmap()ed.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170223162344.GD3595@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of
atomic_t when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-10-git-send-email-elena.reshetova@intel.com
[ Did missing tests/thread-map.c conversion ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-9-git-send-email-elena.reshetova@intel.com
[ Did missing conversion in __machine__remove_thread() ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of
atomic_t when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-8-git-send-email-elena.reshetova@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of
atomic_t when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-7-git-send-email-elena.reshetova@intel.com
[ Did the missing conversion of tests/thread-mg-share.c too ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of
atomic_t when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-6-git-send-email-elena.reshetova@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-5-git-send-email-elena.reshetova@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of
atomic_t when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-4-git-send-email-elena.reshetova@intel.com
[ Reinstated comm_str__get() function, needed when reusing entries in the rbtree ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: alsa-devel@alsa-project.org
Link: http://lkml.kernel.org/r/1487691303-31858-3-git-send-email-elena.reshetova@intel.com
[ fixed mixed conversion to refcount in tests/cpumap.c ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The refcount_t type and corresponding API should be used instead of
atomic_t when the variable is used as a reference counter.

This allows to avoid accidental refcounter overflows that might lead to
use-after-free situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Kook <keescook@chromium.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: alsa-devel@alsa-project.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kees Kook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1487691303-31858-2-git-send-email-elena.reshetova@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To aid in catching bugs when using atomics as a reference count.

This is a trimmed down version with just what is used by tools/ at
this point.

After this, the patches submitted by Elena for tools/ doing the
conversion from atomic_ to recount_ methods can be applied and tested.

To activate it, buint perf with:

  make DEBUG=1 -C tools/perf

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-dqtxsumns9ov0l9r5x398f19@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The kernel has it and some files we got from there would require us
including the userland header for that, so add it conditionally.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-gmwyal7c9vzzttlyk6u59rzn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We've been using an atomic_t implementation subset based on the gcc
builtin functions for a while, now, with refcount.h we need cmpxchg(),
use gcc's __sync_val_compare_and_swap() for that.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-b9zovyxgpa0c4vi3nm0kjo97@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Will be used by refcnt.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-jszriruqfqpez1bkivwfj6qb@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Will be used by atomic_cmpxchg_relaxed(), in turn used by refcount.h.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-kdmovd3l4gw5b1w31ypr6ddv@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Will be included from atomic.h and used in refcount.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-pzrydfee75mhq64kazxmf9it@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

From the kernel, get the gcc one and provide the fallback so that we can
continue build with other compilers, such as with clang.

Will be used by tools/arch/x86/include/asm/cmpxchg.h.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-pecgz6efai4a9euuk4rxuotr@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When using perf stat on an AMD F15h system with the default hw events
attributes, some of the events don't get counted:

 Performance counter stats for 'sleep 1':

          0.749208      task-clock (msec)         #    0.001 CPUs utilized
                 1      context-switches          #    0.001 M/sec
                 0      cpu-migrations            #    0.000 K/sec
                54      page-faults               #    0.072 M/sec
         1,122,815      cycles                    #    1.499 GHz
           286,740      stalled-cycles-frontend   #   25.54% frontend cycles idle
     <not counted>      stalled-cycles-backend                                        (0.00%)
     ^^^^^^^^^^^^
     <not counted>      instructions                                                  (0.00%)
     ^^^^^^^^^^^^
     <not counted>      branches                                                      (0.00%)
     <not counted>      branch-misses                                                 (0.00%)

       1.001550070 seconds time elapsed

The reason is that we have the HW watchdog consuming one PMU counter and
when perf tries to schedule 6 events on 6 counters and some of those
counters are constrained to only a specific subset of PMCs by the
hardware, the event scheduling fails.

So issue a hint to disable the HW watchdog around a perf stat session.

Committer note:

Testing it...

  # perf stat -d usleep 1

   Performance counter stats for 'usleep 1':

          1.180203      task-clock (msec)         #    0.490 CPUs utilized
                 1      context-switches          #    0.847 K/sec
                 0      cpu-migrations            #    0.000 K/sec
                54      page-faults               #    0.046 M/sec
           184,754      cycles                    #    0.157 GHz
           714,553      instructions              #    3.87  insn per cycle
           154,661      branches                  #  131.046 M/sec
             7,247      branch-misses             #    4.69% of all branches
           219,984      L1-dcache-loads           #  186.395 M/sec
            17,600      L1-dcache-load-misses     #    8.00% of all L1-dcache hits    (90.16%)
     <not counted>      LLC-loads                                                     (0.00%)
     <not counted>      LLC-load-misses                                               (0.00%)

       0.002406823 seconds time elapsed

  Some events weren't counted. Try disabling the NMI watchdog:
	echo 0 > /proc/sys/kernel/nmi_watchdog
	perf stat ...
	echo 1 > /proc/sys/kernel/nmi_watchdog
  #
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NIngo Molnar <mingo@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <rric@kernel.org>
Cc: Vince Weaver <vince@deater.net>
Link: http://lkml.kernel.org/r/20170211183218.ijnvb5f7ciyuunx4@pd.tnicSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Reuse events from KnightsLanding for KnightsMill
Signed-off-by: NKarol Wachowski <karol.wachowski@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peter.zijlstra@intel.com>
Cc: Piotr Luc <piotr.luc@intel.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: http://lkml.kernel.org/r/1487591440-25172-1-git-send-email-karol.wachowski@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The '__unreachable' and '__func_stack_frame_non_standard' sections are
only used at compile time.  They're discarded for vmlinux but they
should also be discarded for modules.

Since this is a recurring pattern, prefix the section names with
".discard.".  It's a nice convention and vmlinux.lds.h already discards
such sections.

Also remove the 'a' (allocatable) flag from the __unreachable section
since it doesn't make sense for a discarded section.
Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: d1091c7f ("objtool: Improve detection of BUG() and other dead ends")
Link: http://lkml.kernel.org/r/20170301180444.lhd53c5tibc4ns77@trebleSigned-off-by: NIngo Molnar <mingo@kernel.org>

Fix typos and add the following to the scripts/spelling.txt:

  overrided||overridden

Link: http://lkml.kernel.org/r/1481573103-11329-22-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix typos and add the following to the scripts/spelling.txt:

  an one||a one

I dropped the "an" before "one or more" in
drivers/net/ethernet/sfc/mcdi_pcol.h.

Link: http://lkml.kernel.org/r/1481573103-11329-6-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix typos and add the following to the scripts/spelling.txt:

  an union||a union

Link: http://lkml.kernel.org/r/1481573103-11329-5-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix typos and add the following to the scripts/spelling.txt:

  an user||a user
  an userspace||a userspace

I also added "userspace" to the list since it is a common word in Linux.
I found some instances for "an userfaultfd", but I did not add it to the
list.  I felt it is endless to find words that start with "user" such as
"userland" etc., so must draw a line somewhere.

Link: http://lkml.kernel.org/r/1481573103-11329-4-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently it uses %i for bitmasks, which makes it difficult to properly
decode the values.  Use %x instead.

Link: http://lkml.kernel.org/r/b7b4c45d-2f21-de6c-d1c8-16c8386da27c@list.ruSigned-off-by: NStas Sergeev <stsp@users.sourceforge.net>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This saves 32 bytes on my x86-64 build, mostly due to alignment
considerations and sharing more code between find_next_bit and
find_next_zero_bit, but it does save a couple of instructions.

There's really two parts to this commit:
 - First, the first half of the test: (!nbits || start >= nbits) is
   trivially a subset of the second half, since nbits and start are both
   unsigned
 - Second, while looking at the disassembly, I noticed that GCC was
   predicting the branch taken. Since this is a failure case, it's
   clearly the less likely of the two branches, so add an unlikely() to
   override GCC's heuristics.

[mawilcox@microsoft.com: v2]
  Link: http://lkml.kernel.org/r/1483709016-1834-1-git-send-email-mawilcox@linuxonhyperv.com
Link: http://lkml.kernel.org/r/1483709016-1834-1-git-send-email-mawilcox@linuxonhyperv.comSigned-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Acked-by: NYury Norov <ynorov@caviumnetworks.com>
Acked-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now when madvise(MADV_REMOVE) notifies uffd reader, we should verify
that appliciation actually sees zeros at the removed range.

Link: http://lkml.kernel.org/r/1484814154-1557-4-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: NAndrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "userfaultfd: non-cooperative: add madvise() event for
MADV_REMOVE request".

These patches add notification of madvise(MADV_REMOVE) event to
non-cooperative userfaultfd monitor.

The first pacth renames EVENT_MADVDONTNEED to EVENT_REMOVE along with
relevant functions and structures.  Using _REMOVE instead of
_MADVDONTNEED describes the event semantics more clearly and I hope it's
not too late for such change in the ABI.

This patch (of 3):

The UFFD_EVENT_MADVDONTNEED purpose is to notify uffd monitor about
removal of certain range from address space tracked by userfaultfd.
Hence, UFFD_EVENT_REMOVE seems to better reflect the operation
semantics.  Respectively, 'madv_dn' field of uffd_msg is renamed to
'remove' and the madvise_userfault_dontneed callback is renamed to
userfaultfd_remove.

Link: http://lkml.kernel.org/r/1484814154-1557-2-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: NAndrea Arcangeli <aarcange@redhat.com>
Acked-by: NHillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The BUG() macro's use of __builtin_unreachable() via the unreachable()
macro tells gcc that the instruction is a dead end, and that it's safe
to assume the current code path will not execute past the previous
instruction.

On x86, the BUG() macro is implemented with the 'ud2' instruction.  When
objtool's branch analysis sees that instruction, it knows the current
code path has come to a dead end.

Peter Zijlstra has been working on a patch to change the WARN macros to
use 'ud2'.  That patch will break objtool's assumption that 'ud2' is
always a dead end.

Generally it's best for objtool to avoid making those kinds of
assumptions anyway.  The more ignorant it is of kernel code internals,
the better.

So create a more generic way for objtool to detect dead ends by adding
an annotation to the unreachable() macro.  The annotation stores a
pointer to the end of the unreachable code path in an '__unreachable'
section.  Objtool can read that section to find the dead ends.
Tested-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/41a6d33971462ebd944a1c60ad4bf5be86c17b77.1487712920.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This will verify -EINVAL is returned with hugetlbfs/shmem and it'll do a
functional test of UFFDIO_ZEROPAGE on anonymous memory.

Link: http://lkml.kernel.org/r/20161216144821.5183-42-aarcange@redhat.comSigned-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add test for userfaultfd events used in non-cooperative scenario when
the process that monitors the userfaultfd and handles user faults is not
the same process that causes the page faults.

Link: http://lkml.kernel.org/r/20161216144821.5183-41-aarcange@redhat.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With future addition of event tests, copy_page will be called with
different userfault file descriptors

Link: http://lkml.kernel.org/r/20161216144821.5183-40-aarcange@redhat.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>