The 'trace_fields' sort key is similar as 'trace' sort key, but it shows
each fields separately.  Each event will get different columns as their
fields.

  $ perf report -s trace_fields --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 20K of event 'kmem:kmalloc'
  # Event count (approx.): 20533
  #
  # Overhead  Command           call_site                 ptr  bytes_req  bytes_alloc            gfp_flags
  # ........  .......  ..................  ..................  .........  ...........  ...................
  #
      99.89%  perf       ffffffffa01d4396  0xffff8803ffb79720         96           96    GFP_NOFS|GFP_ZERO
       0.06%  sleep      ffffffff8114e1cd  0xffff8803d228a000       4096         4096           GFP_KERNEL
       0.03%  perf       ffffffff811d6ae6  0xffff8803f7678f00        240          256  GFP_KERNEL|GFP_ZERO
       0.00%  perf       ffffffff812263c1  0xffff880406172380        128          128           GFP_KERNEL
       0.00%  perf       ffffffff812264b9  0xffff8803ffac1600        504          512           GFP_KERNEL
       0.00%  perf       ffffffff81226634  0xffff880401dc5280         28           32           GFP_KERNEL
       0.00%  sleep      ffffffff81226da9  0xffff8803ffac3a00        392          512           GFP_KERNEL

  # Samples: 20K of event 'kmem:kfree'
  # Event count (approx.): 20597
  #
  # Overhead           call_site                 ptr
  # ........  ..................  ..................
  #
      99.58%    ffffffffa01d85ad  0xffff8803ffb79720
       0.07%    ffffffff81443f5c  0xffff8803f7669400
       0.02%    ffffffff811d5753  0xffff8803f7678f00
       0.01%    ffffffff81443f5c  0xffff8803f766be00
       0.01%    ffffffff8114e359  0xffff8803d228a000
       0.01%    ffffffff81443f5c  0xffff8800d156dc00
       0.01%    ffffffff81443f5c  0xffff8803f7669400
       0.01%    ffffffff8114e359  0xffff8803d228a000
       0.01%    ffffffff8114e359  0xffff8803d228a000
       0.01%    ffffffff8114e359  0xffff8803d228a000
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-13-git-send-email-namhyung@kernel.org
[ Combined with "perf tools: Fix segfault when using -s trace_fields" ]
Link: http://lkml.kernel.org/r/1451991518-25673-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When there are multiple events, each dynamic sort key is defined just
for one event.  In this case other events will always show "N/A" for
those fields.  But they are meaningless and consume precious screen
width.

Let's skip those undefined dynamic fields.

  $ perf record -e kmem:kmalloc,kmem:kfree -a sleep 1

  $ perf report -s 'comm,kmalloc.*' --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 20K of event 'kmem:kmalloc'
  # Event count (approx.): 20533
  #
  # Overhead  Command           call_site                 ptr  bytes_req  bytes_alloc            gfp_flags
  # ........  .......  ..................  ..................  .........  ...........  ...................
  #
      99.89%  perf       ffffffffa01d4396  0xffff8803ffb79720         96           96    GFP_NOFS|GFP_ZERO
       0.06%  sleep      ffffffff8114e1cd  0xffff8803d228a000       4096         4096           GFP_KERNEL
       0.03%  perf       ffffffff811d6ae6  0xffff8803f7678f00        240          256  GFP_KERNEL|GFP_ZERO
       0.00%  perf       ffffffff812263c1  0xffff880406172380        128          128           GFP_KERNEL
       0.00%  perf       ffffffff812264b9  0xffff8803ffac1600        504          512           GFP_KERNEL
       0.00%  perf       ffffffff81226634  0xffff880401dc5280         28           32           GFP_KERNEL
       0.00%  sleep      ffffffff81226da9  0xffff8803ffac3a00        392          512           GFP_KERNEL

  # Samples: 20K of event 'kmem:kfree'
  # Event count (approx.): 20597
  #
  # Overhead  Command
  # ........  ..............
  #
      99.63%  perf
       0.14%  sleep
       0.11%  irq/36-iwlwifi
       0.11%  kworker/u16:0
       0.01%  Xorg
       0.00%  firefox
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-12-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Support '*' character for field name to add all (non-common) fields as
sort keys easily.

  $ perf report -s 'switch.*' --stdio
  ...
  # Overhead    prev_comm  prev_pid   prev_prio  prev_state     next_comm  next_pid  next_prio
  # ........  ...........  .........  .........  ..........  ............  ........  .........
  #
       3.82%    swapper/0         0         120           0   netctl-auto     18711        120
       3.75%  netctl-auto     18711         120           1     swapper/0         0        120
       2.24%    swapper/1         0         120           0   netctl-auto     18709        120
       2.24%  netctl-auto     18709         120           1     swapper/1         0        120
       1.80%    swapper/2         0         120           0   rcu_preempt         7        120
       1.80%    swapper/2         0         120           0   netctl-auto     18711        120
       1.80%  rcu_preempt         7         120           1     swapper/2         0        120
       1.80%  netctl-auto     18711         120           1     swapper/2         0        120
  ...
Suggested-and-acked-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-11-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The dynamic sort key requires event name but specifying full event name
is rather inconvenient.  This patch adds more ways to identify the event
in a more compact way.

  1. If session has just one event, event name can be omitted.
  2. Events can be accessed by index preceded by a percent sign.
  3. A part of the name can be used, if it's not ambiguous.  The partial
     name should not contain ':' in it.
  4. Full system + event name is still used, it should contain ':'.

So in the below example all does same thing:

  $ perf record -e sched:sched_switch -a sleep 1

  $ perf report -s next_pid,next_comm
  $ perf report -s %1.next_pid,%1.next_comm
  $ perf report -s switch.next_pid,switch.next_comm
  $ perf report -s sched:sched_switch.next_pid,sched:sched_switch.next_comm
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-10-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The --raw-trace option allows disabling pretty printing by the event's
print_fmt or plugin.  Besides that, each dynamic sort key now can
receive a 'raw' suffix separated by '/' to ask for the raw trace of a
specific field.

  $ perf report -s comm,kmem:kmalloc.gfp_flags
  ...
  # Overhead  Command            gfp_flags
  # ........  .......  ...................
  #
      99.89%  perf       GFP_NOFS|GFP_ZERO
       0.06%  sleep             GFP_KERNEL
       0.03%  perf     GFP_KERNEL|GFP_ZERO
       0.01%  perf              GFP_KERNEL

Now

  $ perf report -s comm,kmem:kmalloc.gfp_flags --raw-trace
or
  $ perf report -s comm,kmem:kmalloc.gfp_flags/raw
  ...
  # Overhead  Command   gfp_flags
  # ........  .......  ..........
  #
      99.89%  perf          32848
       0.06%  sleep           208
       0.03%  perf          32976
       0.01%  perf            208
Suggested-and-Acked-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-9-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 'trace' sort key is to show tracepoint event output using either
print fmt or plugin.  For example sched_switch event (using plugin) will
show output like below:

  # perf record -e sched:sched_switch -a usleep 10
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.197 MB perf.data (69 samples) ]
  #

  $ perf report -s trace --stdio
  ...
  # Overhead  Trace output
  # ........  ...................................................
  #
       9.48%  swapper/0:0 [120] R ==> transmission-gt:17773 [120]
       9.48%  transmission-gt:17773 [120] S ==> swapper/0:0 [120]
       9.04%  swapper/2:0 [120] R ==> transmission-gt:17773 [120]
       8.92%  transmission-gt:17773 [120] S ==> swapper/2:0 [120]
       5.25%  swapper/0:0 [120] R ==> kworker/0:1H:109 [100]
       5.21%  kworker/0:1H:109 [100] S ==> swapper/0:0 [120]
       1.78%  swapper/3:0 [120] R ==> transmission-gt:17773 [120]
       1.78%  transmission-gt:17773 [120] S ==> swapper/3:0 [120]
       1.53%  Xephyr:6524 [120] S ==> swapper/0:0 [120]
       1.53%  swapper/0:0 [120] R ==> Xephyr:6524 [120]
       1.17%  swapper/2:0 [120] R ==> irq/33-iwlwifi:233 [49]
       1.13%  irq/33-iwlwifi:233 [49] S ==> swapper/2:0 [120]

Note that the 'trace' sort key works only for tracepoint events.  If
it's used to other type of events, just "N/A" will be printed.
Suggested-and-acked-by: NJiri Olsa <jolsa@redhat.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-8-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Each tracepoint event has format string for print to improve
readability.  Try to parse the output and match the field name.  If it
finds one, use that for the result.  If not, fallbacks to the original
output.

For example, sort on kmem:kmalloc.gfp_flags looks like below:
(Note: libtraceevent plugins are not installed on my system.  They might
affect the output below)

Before:
  # Overhead  Command   gfp_flags
  # ........  .......  ..........
  #
      99.89%  perf          32848
       0.06%  sleep           208
       0.03%  perf          32976
       0.01%  perf            208

After:
  # Overhead  Command            gfp_flags
  # ........  .......  ...................
  #
      99.89%  perf       GFP_NOFS|GFP_ZERO
       0.06%  sleep             GFP_KERNEL
       0.03%  perf     GFP_KERNEL|GFP_ZERO
       0.01%  perf              GFP_KERNEL
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-7-git-send-email-namhyung@kernel.org
[ Fixed clash with earlier, updated patch in this patchkit ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The existing sort keys are less useful for tracepoint events in that
they are always sampled at the same place, the function where the
tracepoint is located.

For example, a 'perf report' on sched:sched_switch event looks like the
following:

  # Overhead  Command          Shared Object     Symbol
  # ........  ...............  ................  ..............
  #
      47.22%  swapper          [kernel.vmlinux]  [k] __schedule
      21.67%  transmission-gt  [kernel.vmlinux]  [k] __schedule
       8.23%  netctl-auto      [kernel.vmlinux]  [k] __schedule
       5.53%  kworker/0:1H     [kernel.vmlinux]  [k] __schedule
       1.98%  Xephyr           [kernel.vmlinux]  [k] __schedule
       1.33%  irq/33-iwlwifi   [kernel.vmlinux]  [k] __schedule
       1.17%  wpa_cli          [kernel.vmlinux]  [k] __schedule
       1.13%  rcu_preempt      [kernel.vmlinux]  [k] __schedule
       0.85%  ksoftirqd/0      [kernel.vmlinux]  [k] __schedule
       0.77%  Timer            [kernel.vmlinux]  [k] __schedule

In fact, tracepoints have meaningful information in their fields but
there's no way to use in 'perf report' currently.  The dynamic sort keys
are introduced in this patc to overcome this limitation.

The sched:sched_switch events have following fields:

  # sudo cat /sys/kernel/debug/tracing/events/sched/sched_switch/format
  name: sched_switch
  ID: 268
  format:
	field:unsigned short common_type;         offset:0; size:2; signed:0;
	field:unsigned char common_flags;         offset:2; size:1; signed:0;
	field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
	field:int common_pid;                     offset:4; size:4; signed:1;

	field:char prev_comm[16]; offset:8;  size:16; signed:1;
	field:pid_t prev_pid;     offset:24; size:4;  signed:1;
	field:int prev_prio;      offset:28; size:4;  signed:1;
	field:long prev_state;    offset:32; size:8;  signed:1;
	field:char next_comm[16]; offset:40; size:16; signed:1;
	field:pid_t next_pid;     offset:56; size:4;  signed:1;
	field:int next_prio;      offset:60; size:4;  signed:1;

  print fmt: "prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==>
              next_comm=%s next_pid=%d next_prio=%d",
    REC->prev_comm, REC->prev_pid, REC->prev_prio,
    REC->prev_state & (2048-1) ? __print_flags(REC->prev_state & (2048-1),
    "|", { 1, "S"} , { 2, "D" }, { 4, "T" }, { 8, "t" }, { 16, "Z" }, { 32, "X" },
    { 64, "x" }, { 128, "K"}, { 256, "W" }, { 512, "P" }, { 1024, "N" }) : "R",
    REC->prev_state & 2048 ? "+" : "", REC->next_comm, REC->next_pid, REC->next_prio

With dynamic sort keys, you can use <event.field> as a sort key.  Those
dynamic keys are checked and created on demand.  For instance, below is
to sort by next_pid field output on the same data file:

  $ perf report -s comm,sched:sched_switch.next_pid --stdio
  ...
  # Overhead  Command            next_pid
  # ........  ...............  ..........
  #
      21.23%  transmission-gt           0
      20.86%  swapper               17773
       6.62%  netctl-auto               0
       5.25%  swapper                 109
       5.21%  kworker/0:1H              0
       1.98%  Xephyr                    0
       1.98%  swapper                6524
       1.98%  swapper               27478
       1.37%  swapper               27476
       1.17%  swapper                 233

Multiple dynamic sort keys are also supported:

  $ perf report -s comm,sched:sched_switch.next_pid,sched:sched_switch.next_comm --stdio
  ...
  # Overhead  Command            next_pid         next_comm
  # ........  ...............  ..........  ................
  #
      20.86%  swapper               17773   transmission-gt
       9.64%  transmission-gt           0         swapper/0
       9.16%  transmission-gt           0         swapper/2
       5.25%  swapper                 109      kworker/0:1H
       5.21%  kworker/0:1H              0         swapper/0
       2.14%  netctl-auto               0         swapper/2
       1.98%  netctl-auto               0         swapper/0
       1.98%  swapper                6524            Xephyr
       1.98%  swapper               27478       netctl-auto
       1.78%  transmission-gt           0         swapper/3
       1.53%  Xephyr                    0         swapper/0
       1.29%  netctl-auto               0         swapper/1
       1.29%  swapper               27476       netctl-auto
       1.21%  netctl-auto               0         swapper/3
       1.17%  swapper                 233    irq/33-iwlwifi

Note that pid 0 exists for each cpu so have comm of 'swapper/N'.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-6-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is a preparation to support dynamic sort keys for tracepoint
events.  Dynamic sort keys can be created for specific fields in trace
events so it needs the event information.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-5-git-send-email-namhyung@kernel.org
[ Moving the evlist creation earlier in top was split to a previous patch ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is a preparation to support dynamic sort keys for tracepoint
events.  Dynamic sort keys can be created for specific fields in trace
events so it needs the event information, so we need to pass the evlist
to the sort routines, create it sooner so that the next patch can do
that.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-5-git-send-email-namhyung@kernel.org
[ Split from the patch passing the evlist to the sort routines ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The print_event_field() and print_event_fields() functions print basic
information of a given field or event without the print format.  They'll
be used by dynamic sort keys later.

Committer note:

Rename it to pevent_print_field[s]() to get proper namespacing, as
discussed with Steven Rostedt.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450876121-22494-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The raw_data and raw_size fields are to provide tracepoint specific
information.  They will be used by dynamic sort keys later.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450923377-18641-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is a preparation to add more info into the hist_entry.  Also it
already passes too many argument, so passing sample directly will reduce
the overhead of the function call.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1450804030-29193-2-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is a long standing bug with the l1-dcache-stores generic event on
AMD machines.  My perf_event testsuite has been complaining about this
for years and I'm finally getting around to trying to get it fixed.

The data_cache_refills:system event does not make sense for l1-dcache-stores.
Maybe this was a typo and it was meant to be for l1-dcache-store-misses?

In any case, the values returned are nowhere near correct for l1-dcache-stores
and in fact the umask values for the event have completely changed with
fam15h so it makes even less sense than ever.  So just remove it.
Signed-off-by: NVince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1512091134350.24311@vincent-weaver-1.umelst.maine.eduSigned-off-by: NIngo Molnar <mingo@kernel.org>

Knights Landing uncore performance monitoring (perfmon) is derived from
Haswell-EP uncore perfmon with several differences. One notable difference
is in PCI device IDs. Knights Landing uses common PCI device ID for
multiple instances of an uncore PMU device type. In Haswell-EP, each
instance of a PMU device type has a unique device ID.

Knights Landing uncore components that have performance monitoring units
are UBOX, CHA, EDC, MC, M2PCIe, IRP and PCU. Perfmon registers in EDC, MC,
IRP, and M2PCIe reside in the PCIe configuration space. Perfmon registers
in UBOX, CHA and PCU are accessed via the MSR interface.

For more details, please refer to the public document:

  https://software.intel.com/sites/default/files/managed/15/8d/IntelXeonPhi%E2%84%A2x200ProcessorPerformanceMonitoringReferenceManual_Volume1_Registers_v0%206.pdfSigned-off-by: NHarish Chegondi <harish.chegondi@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Harish Chegondi <harish.chegondi@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/8ac513981264c3eb10343a3f523f19cc5a2d12fe.1449470704.git.harish.chegondi@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Call uncore_pci_box_ctl() function to get the PMON box control MSR offset
instead of hard coding the offset. This would allow us to use this
snbep_uncore_pci_init_box() function for other PCI PMON devices whose box
control MSR offset is different from SNBEP_PCI_PMON_BOX_CTL.
Signed-off-by: NHarish Chegondi <harish.chegondi@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Harish Chegondi <harish.chegondi@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/872e8ef16cfc38e5ff3b45fac1094e6f1722e4ad.1449470704.git.harish.chegondi@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Knights Landing core is based on Silvermont core with several differences.
Like Silvermont, Knights Landing has 8 pairs of LBR MSRs. However, the
LBR MSRs addresses match those of the Xeon cores' first 8 pairs of LBR MSRs
Unlike Silvermont, Knights Landing supports hyperthreading. Knights Landing
offcore response events config register mask is different from that of the
Silvermont.

This patch was developed based on a patch from Andi Kleen.

For more details, please refer to the public document:

  https://software.intel.com/sites/default/files/managed/15/8d/IntelXeonPhi%E2%84%A2x200ProcessorPerformanceMonitoringReferenceManual_Volume1_Registers_v0%206.pdfSigned-off-by: NHarish Chegondi <harish.chegondi@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Harish Chegondi <harish.chegondi@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukasz Anaczkowski <lukasz.anaczkowski@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/d14593c7311f78c93c9cf6b006be843777c5ad5c.1449517401.git.harish.chegondi@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The uncore subsystem for Broadwell-EP is similar to Haswell-EP.
There are some differences in pci device IDs, box number and
constraints. This patch extends the Broadwell-DE codes to support
Broadwell-EP.
Signed-off-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1449176411-9499-1-git-send-email-kan.liang@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Actually, rapl_sysfs_show is a duplicate of perf_event_sysfs_show. We
prefer to use the unified interface.
Signed-off-by: NHuang Rui <ray.huang@amd.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dasaratharaman Chandramouli<dasaratharaman.chandramouli@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <rric@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1449223661-2437-1-git-send-email-ray.huang@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patch updates the PEBS support for Intel Atom to provide
an alias for the cycles:pp event used by perf record/top by default
nowadays.

On Atom, only INST_RETIRED:ANY supports PEBS, so we use this event
instead with a large cmask to count cycles. Given that Core2 has
the same issue, we use the intel_pebs_aliases_core2() function for Atom
as well.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1449172990-30183-3-git-send-email-eranian@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patch fixes broken PEBS support on Intel Atom and Core2
due to wrong pointer arithmetic in intel_pmu_drain_pebs_core().

The get_next_pebs_record_by_bit() was called on PEBS format fmt0
which does not use the pebs_record_nhm layout.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Fixes: 21509084 ("perf/x86/intel: Handle multiple records in the PEBS buffer")
Link: http://lkml.kernel.org/r/1449182000-31524-3-git-send-email-eranian@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patches fixes the LBR kernel crashes on Intel Atom.

The kernel was assuming that if the CPU supports 64-bit format
LBR, then it has an LBR_SELECT MSR. Atom uses 64-bit LBR format
but does not have LBR_SELECT. That was causing NULL pointer
dereferences in a couple of places.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Fixes: 96f3eda6 ("perf/x86/intel: Fix static checker warning in lbr enable")
Link: http://lkml.kernel.org/r/1449182000-31524-2-git-send-email-eranian@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patch fixes a bug in the filter_events() function.

The patch fixes the bug whereby if some mappings did not
exist, e.g., STALLED_CYCLES_FRONTEND, then any event after it
in the attrs array would disappear from the published list of
events in /sys/devices/cpu/events. This could be verified
easily on any system post SNB (which do not publish
STALLED_CYCLES_FRONTEND):

	$ ./perf stat -e cycles,ref-cycles true
	Performance counter stats for 'true':
              1,217,348      cycles
	<not supported>      ref-cycles

The problem is that in filter_events() there is an assumption
that the argument (attrs) is organized in increasing continuous
event indexes related to the event_map(). But if we remove the
non-supported events by shifing the position in the array, then
the lookup x86_pmu.event_map() needs to compensate for it, otherwise
we are looking up the wrong index. This patch corrects this problem
by compensating for the deleted events and with that ref-cycles
reappears (here shown on Haswell):

	$ perf stat -e ref-cycles,cycles true
	Performance counter stats for 'true':
         4,525,910      ref-cycles
         1,064,920      cycles
       0.002943888 seconds time elapsed
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: jolsa@kernel.org
Cc: kan.liang@intel.com
Fixes: 8300daa2 ("perf/x86: Filter out undefined events from sysfs events attribute")
Link: http://lkml.kernel.org/r/1449516805-6637-1-git-send-email-eranian@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Add a new 'three-p' precise level, that uses INST_RETIRED.PREC_DIST as
base. The basic mechanism of abusing the inverse cmask to get all
cycles works the same as before.

PREC_DIST is available on Sandy Bridge or later. It had some problems
on Sandy Bridge, so we only use it on IvyBridge and later. I tested it
on Broadwell and Skylake.

PREC_DIST has special support for avoiding shadow effects, which can
give better results compare to UOPS_RETIRED. The drawback is that
PREC_DIST can only schedule on counter 1, but that is ok for cycle
sampling, as there is normally no need to do multiple cycle sampling
runs in parallel. It is still possible to run perf top in parallel, as
that doesn't use precise mode. Also of course the multiplexing can
still allow parallel operation.

:pp stays with the previous event.

Example:

Sample a loop with 10 sqrt with old cycles:pp

	  0.14 │10:   sqrtps %xmm1,%xmm0     <--------------
	  9.13 │      sqrtps %xmm1,%xmm0
	 11.58 │      sqrtps %xmm1,%xmm0
	 11.51 │      sqrtps %xmm1,%xmm0
	  6.27 │      sqrtps %xmm1,%xmm0
	 10.38 │      sqrtps %xmm1,%xmm0
	 12.20 │      sqrtps %xmm1,%xmm0
	 12.74 │      sqrtps %xmm1,%xmm0
	  5.40 │      sqrtps %xmm1,%xmm0
	 10.14 │      sqrtps %xmm1,%xmm0
	 10.51 │    ↑ jmp    10

We expect all 10 sqrt to get roughly the sample number of samples.

But you can see that the instruction directly after the JMP is
systematically underestimated in the result, due to sampling shadow
effects.

With the new PREC_DIST based sampling this problem is gone and all
instructions show up roughly evenly:

	  9.51 │10:   sqrtps %xmm1,%xmm0
	 11.74 │      sqrtps %xmm1,%xmm0
	 11.84 │      sqrtps %xmm1,%xmm0
	  6.05 │      sqrtps %xmm1,%xmm0
	 10.46 │      sqrtps %xmm1,%xmm0
	 12.25 │      sqrtps %xmm1,%xmm0
	 12.18 │      sqrtps %xmm1,%xmm0
	  5.26 │      sqrtps %xmm1,%xmm0
	 10.13 │      sqrtps %xmm1,%xmm0
	 10.43 │      sqrtps %xmm1,%xmm0
	  0.16 │    ↑ jmp    10

Even with PREC_DIST there is still sampling skid and the result is not
completely even, but systematic shadow effects are significantly
reduced.

The improvements are mainly expected to make a difference in high IPC
code. With low IPC it should be similar.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1448929689-13771-2-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

I added UOPS_RETIRED.ALL by mistake to the Skylake PEBS event list for
cycles:pp. But the event is not documented for Skylake, and has some
issues.

The recommended replacement for cycles:pp is to use
INST_RETIRED.ANY+pebs as a base, similar to what CPUs before Sandy
Bridge did. This new event is called INST_RETIRED.TOTAL_CYCLES_PS. The
event is not really new, but has been already used by perf before
Sandy Bridge for the original cycles:p

Note the SDM doesn't document that event either, but it's being
documented in the latest version of the event list on:

  https://download.01.org/perfmon/SKL

This patch does:

 - Remove UOPS_RETIRED.ALL from the Skylake PEBS event list

 - Add INST_RETIRED.ANY to the Skylake PEBS event list, and an table entry to
   allow cmask=16,inv=1 for cycles:pp

 - We don't need an extra entry for the base INST_RETIRED event,
   because it is already covered by the catch-all PEBS table entry.

 - Switch Skylake to use the Core2 PEBS alias (which is
   INST_RETIRED.TOTAL_CYCLES_PS)
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1448929689-13771-1-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Normally we drop PEBS events with a zero status field. But when
there is only a single PEBS event active we can assume the
PEBS record is for that event. The PEBS buffer is always flushed
when PEBS events are disabled, so there is no risk of mishandling
state PEBS records this way.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1449177740-5422-2-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

The recent commit:

  75f80859 ("perf/x86/intel/pebs: Robustify PEBS buffer drain")

causes lots of warnings on different CPUs before Skylake
when running PEBS intensive workloads.

They can have a zero status field in the PEBS record when
PEBS is racing with clearing of GLOBAl_STATUS.

This also can cause hangs (it seems there are still
problems with printk in NMI).

Disable the warning, but still ignore the record.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1449177740-5422-1-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patch collapses the two 'hard' cases, which are
perf_event_{dis,en}able().

I cannot seem to convince myself the current code is correct.

So starting with perf_event_disable(); we don't strictly need to test
for event->state == ACTIVE, ctx->is_active is enough. If the event is
not scheduled while the ctx is, __perf_event_disable() still does the
right thing.  Its a little less efficient to IPI in that case,
over-all simpler.

For perf_event_enable(); the same goes, but I think that's actually
broken in its current form. The current condition is: ctx->is_active
&& event->state == OFF, that means it doesn't do anything when
!ctx->active && event->state == OFF. This is wrong, it should still
mark the event INACTIVE in that case, otherwise we'll still not try
and schedule the event once the context becomes active again.

This patch implements the two function using the new
event_function_call() and does away with the tricky event->state
tests.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: NAlexander Shishkin <alexander.shishkin@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Signed-off-by: NIngo Molnar <mingo@kernel.org>

There's a race on CPU unplug where we free the swevent hash array
while it can still have events on. This will result in a
use-after-free which is BAD.

Simply do not free the hash array on unplug. This leaves the thing
around and no use-after-free takes place.

When the last swevent dies, we do a for_each_possible_cpu() iteration
anyway to clean these up, at which time we'll free it, so no leakage
will occur.
Reported-by: NSasha Levin <sasha.levin@oracle.com>
Tested-by: NSasha Levin <sasha.levin@oracle.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

I managed to tickle this warning:

  [ 2338.884942] ------------[ cut here ]------------
  [ 2338.890112] WARNING: CPU: 13 PID: 35162 at ../kernel/events/core.c:2702 task_ctx_sched_out+0x6b/0x80()
  [ 2338.900504] Modules linked in:
  [ 2338.903933] CPU: 13 PID: 35162 Comm: bash Not tainted 4.4.0-rc4-dirty #244
  [ 2338.911610] Hardware name: Intel Corporation S2600GZ/S2600GZ, BIOS SE5C600.86B.02.02.0002.122320131210 12/23/2013
  [ 2338.923071]  ffffffff81f1468e ffff8807c6457cb8 ffffffff815c680c 0000000000000000
  [ 2338.931382]  ffff8807c6457cf0 ffffffff810c8a56 ffffe8ffff8c1bd0 ffff8808132ed400
  [ 2338.939678]  0000000000000286 ffff880813170380 ffff8808132ed400 ffff8807c6457d00
  [ 2338.947987] Call Trace:
  [ 2338.950726]  [<ffffffff815c680c>] dump_stack+0x4e/0x82
  [ 2338.956474]  [<ffffffff810c8a56>] warn_slowpath_common+0x86/0xc0
  [ 2338.963195]  [<ffffffff810c8b4a>] warn_slowpath_null+0x1a/0x20
  [ 2338.969720]  [<ffffffff811a49cb>] task_ctx_sched_out+0x6b/0x80
  [ 2338.976244]  [<ffffffff811a62d2>] perf_event_exec+0xe2/0x180
  [ 2338.982575]  [<ffffffff8121fb6f>] setup_new_exec+0x6f/0x1b0
  [ 2338.988810]  [<ffffffff8126de83>] load_elf_binary+0x393/0x1660
  [ 2338.995339]  [<ffffffff811dc772>] ? get_user_pages+0x52/0x60
  [ 2339.001669]  [<ffffffff8121e297>] search_binary_handler+0x97/0x200
  [ 2339.008581]  [<ffffffff8121f8b3>] do_execveat_common.isra.33+0x543/0x6e0
  [ 2339.016072]  [<ffffffff8121fcea>] SyS_execve+0x3a/0x50
  [ 2339.021819]  [<ffffffff819fc165>] stub_execve+0x5/0x5
  [ 2339.027469]  [<ffffffff819fbeb2>] ? entry_SYSCALL_64_fastpath+0x12/0x71
  [ 2339.034860] ---[ end trace ee1337c59a0ddeac ]---

Which is a WARN_ON_ONCE() indicating that cpuctx->task_ctx is not
what we expected it to be.

This is because context switches can swap the task_struct::perf_event_ctxp[]
pointer around. Therefore you have to either disable preemption when looking
at current, or hold ctx->lock.

Fix perf_event_enable_on_exec(), it loads current->perf_event_ctxp[]
before disabling interrupts, therefore a preemption in the right place
can swap contexts around and we're using the wrong one.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: syzkaller <syzkaller@googlegroups.com>
Link: http://lkml.kernel.org/r/20151210195740.GG6357@twins.programming.kicks-ass.netSigned-off-by: NIngo Molnar <mingo@kernel.org>

Merge tag 'perf-core-for-mingo-3' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull new perf tool feature from Arnaldo Carvalho de Melo:

" User visible changes:

  - Generate perf.data files from 'perf stat', to tap into the scripting
    capabilities perf has instead of defining a 'perf stat' specific scripting
    support to calculate event ratios, etc. Simple example:

    $ perf stat record -e cycles usleep 1

     Performance counter stats for 'usleep 1':

           1,134,996      cycles

         0.000670644 seconds time elapsed

    $ perf stat report

     Performance counter stats for '/home/acme/bin/perf stat record -e cycles usleep 1':

           1,134,996      cycles

         0.000670644 seconds time elapsed

    $

    It generates PERF_RECORD_ userspace records to store the details:

    $ perf report -D | grep PERF_RECORD
    0xf0 [0x28]: PERF_RECORD_THREAD_MAP nr: 1 thread: 27637
    0x118 [0x12]: PERF_RECORD_CPU_MAP nr: 1 cpu: 65535
    0x12a [0x40]: PERF_RECORD_STAT_CONFIG
    0x16a [0x30]: PERF_RECORD_STAT
    -1 -1 0x19a [0x40]: PERF_RECORD_MMAP -1/0: [0xffffffff81000000(0x1f000000) @ 0xffffffff81000000]: x [kernel.kallsyms]_text
    0x1da [0x18]: PERF_RECORD_STAT_ROUND
    [acme@ssdandy linux]$

    An effort was made to make perf.data files generated like this to not
    generate cryptic messages when processed by older tools.

    The 'perf script' bits need rebasing, will go up later.

  Jiri's cover letter for this series:

  The initial attempt defined its own formula lang and allowed triggering user's
  script on the end of the stat command:

    http://marc.info/?l=linux-kernel&m=136742146322273&w=2

  This patchset abandons the idea of new formula language and rather adds support
  to:

    - store stat data into perf.data file
    - add python support to process stat events

  Basically it allows to store stat data into perf.data and post process it with
  python scripts in a similar way we do for sampling data.

  The stat data are stored in new stat, stat-round, stat-config user events.
    stat        - stored for each read syscall of the counter
    stat round  - stored for each interval or end of the command invocation
    stat config - stores all the config information needed to process data
                  so report tool could restore the same output as record

  The python script can now define 'stat__<eventname>_<modifier>' functions
  to get stat events data and 'stat__interval' to get stat-round data.

  See CPI script example in scripts/python/stat-cpi.py."

Also a few other changes:

User visible changes:

  - Make command line options always available, even when they
    depend on some feature being enabled, warning the user about
    use of such options (Wang Nan)

  - Support --vmlinux in perf record, useful, so far, for eBPF,
    where we will set up events that will be used in the record
    session (He Kuang)

  - Automatically disable collecting branch flags and cycles with
    --call-graph lbr. This allows avoiding a bunch of extra MSR
    reads in the PMI on Skylake.  (Andi Kleen)

Infrastructure changes:

  - Dump the stack when a 'perf test -v ' entry segfaults, so far we
    would have to run it under gdb with 'set follow-fork-mode child'
    set to get a proper backtrace (Arnaldo Carvalho de Melo)

  - Initialize the refcnt in 'struct thread' to 1 and fixup its
    users accordingly, so that we try to have the same refcount
    model accross the perf codebase (Arnaldo Carvalho de Melo)

  - More prep work for moving the subcmd infrastructure out of
    tools/perf/ and into tools/lib/subcmd/ to be used by other
    tools/ living utilities (Josh Poimboeuf)

  - Fix 'perf test' hist testcases when kptr_restrict is on (Namhyung Kim)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Merge branch 'perf/urgent' into perf/core, to make sure a cherry-picked commit does not create conflicts
Signed-off-by: NIngo Molnar <mingo@kernel.org>

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

Pull perf/urgent tooling fix from Arnaldo Carvalho de Melo:

  User visible changes:

    - Fix 'perf list' segfault due to lack of support for PERF_CONF_SW_BPF_OUTPUT
      in an array used just for printing available events, robustify the code
      involved (Arnaldo Carvalho de Melo)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Merge tag 'perf-core-for-mingo-2.1' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements from Arnaldo Carvalho de Melo:

User visible changes:

  - Add record.build-id config option to 'perf record', to allow configuring
    in the ~/.perfconfig file if and how build-ids should be processed, allowing
    a permanent setting for options such as -B and -N: (Namhyung Kim)

    $ perf record -h -B -N

     Usage: perf record [<options>] [<command>]
        or: perf record [<options>] -- <command> [<options>]

        -B, --no-buildid       do not collect buildids in perf.data
        -N, --no-buildid-cache do not update the buildid cache

    $

Infrastructure changes:

  - Move code for options parsing and subcommand handling from tools/perf/
    to tools/lib/subcmd/, so that it can be used by other tools/ living
    utilities (Josh Poimboeuf)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Allowing to override record aggr_mode. It's possible to use perf stat
like:

   $ perf stat report -A
   $ perf stat report --per-core
   $ perf stat report --per-socket

To customize the recorded aggregate mode regardless what was used during
the stat record command.
Reported-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1446734469-11352-19-git-send-email-jolsa@kernel.org
[ Renamed 'stat' parameter to 'st' to fix 'already defined' build error with older distros (e.g. RHEL6.7) ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Adding processing of event update events, so perf stat report can store
additional info for events - unit,scale,name.

Committer note:

Before:

  # perf stat record -e power/energy-cores/ -a
  ^C
  Performance counter stats for 'system wide':

             77.41 Joules power/energy-cores/

       1.597176695 seconds time elapsed

  # perf stat report

  Performance counter stats for '/home/acme/bin/perf stat record -e power/energy-cores/ -a':

   332,488,114,176      power/energy-cores/

       1.597176695 seconds time elapsed

  #

After, using the same perf.data file generated in the "Before" case
above:

  # perf stat report

  Performance counter stats for '/home/acme/bin/perf stat record -e power/energy-cores/ -a':

             77.41 Joules power/energy-cores/

       1.597176695 seconds time elapsed

  #
Reported-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1446734469-11352-17-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Adding processing of stat and stat round events.

The stat data com in stat events, using generic function
process_stat_round_event to store data under perf_evsel object.

The stat-round events comes each interval or as last event in non
interval mode. The function process_stat_round_event process stored data
for each perf_evsel object and print it out.

Committer note:

After this patch:

  $ perf stat record usleep 1

   Performance counter stats for 'usleep 1':

        0.498381  task-clock (msec)       #    0.571 CPUs utilized
               2  context-switches        #    0.004 M/sec
               0  cpu-migrations          #    0.000 K/sec
             149  page-faults             #    0.299 M/sec
       1,271,635  cycles                  #    2.552 GHz
         928,712  stalled-cycles-frontend #   73.03% frontend cycles idle
         663,286  stalled-cycles-backend  #   52.16% backend  cycles idle
         792,614  instructions            #    0.62  insns per cycle
                                          #    1.17  stalled cycles per insn
         136,850  branches                #  274.589 M/sec
   <not counted>  branch-misses            (0.00%)

     0.000873419 seconds time elapsed

  $
  $ perf stat report

   Performance counter stats for '/home/acme/bin/perf stat record usleep 1':

        0.498381  task-clock (msec)       #    0.571 CPUs utilized
               2  context-switches        #    0.004 M/sec
               0  cpu-migrations          #    0.000 K/sec
             149  page-faults             #    0.299 M/sec
       1,271,635  cycles                  #    2.552 GHz
         928,712  stalled-cycles-frontend #   73.03% frontend cycles idle
         663,286  stalled-cycles-backend  #   52.16% backend  cycles idle
         792,614  instructions            #    0.62  insns per cycle
                                          #    1.17  stalled cycles per insn
         136,850  branches                #  274.589 M/sec
   <not counted>  branch-misses            (0.00%)

     0.000873419 seconds time elapsed

  $
Reported-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1446734469-11352-16-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

So we have csv_sep properly initialized before report command leg.
Reported-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1446734469-11352-18-git-send-email-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Using perf.data's perf_env data to initialize aggregate config.
Reported-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1446734469-11352-15-git-send-email-jolsa@kernel.org
[ s/stat/st/g, s/socket/socket_id/g to fix 'already defined' build error with older distros (e.g. RHEL6.7) ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>