This reverts commit 9a92b479 ("perf
tools: Improve thread comm resolution in perf sched") and fixes the
real bug.

The bug was elsewhere:

We are failing to resolve thread names in perf sched because the
table of threads we are building, on top of comm events, has a per
process granularity. But perf sched, unlike the other perf tools,
needs a per thread granularity as we are profiling every tasks
individually.

So fix it by building our threads table using the tid instead of
the pid as the thread identifier.

v2: Revert the previous fix - it is not really needed
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1255028657-11158-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When we get sched traces that involve a task that was already
created before opening the event, we won't have the comm event for
it.

So if we can't find the comm event for a given thread, we look at
the traces that may contain these informations.

Before:

 ata/1:371             |      0.000 ms |        1 | avg: 3988.693 ms | max: 3988.693 ms |
 kondemand/1:421       |      0.096 ms |        3 | avg:  345.346 ms | max: 1035.989 ms |
 kondemand/0:420       |      0.025 ms |        3 | avg:  421.332 ms | max:  964.014 ms |
 :5124:5124            |      0.103 ms |        5 | avg:   74.082 ms | max:  277.194 ms |
 :6244:6244            |      0.691 ms |        9 | avg:  125.655 ms | max:  271.306 ms |
 firefox:5080          |      0.924 ms |        5 | avg:   53.833 ms | max:  257.828 ms |
 npviewer.bin:6225     |     21.871 ms |       53 | avg:   22.462 ms | max:  220.835 ms |
 :6245:6245            |      9.631 ms |       21 | avg:   41.864 ms | max:  213.349 ms |

After:

 ata/1:371             |      0.000 ms |        1 | avg: 3988.693 ms | max: 3988.693 ms |
 kondemand/1:421       |      0.096 ms |        3 | avg:  345.346 ms | max: 1035.989 ms |
 kondemand/0:420       |      0.025 ms |        3 | avg:  421.332 ms | max:  964.014 ms |
 firefox:5124          |      0.103 ms |        5 | avg:   74.082 ms | max:  277.194 ms |
 npviewer.bin:6244     |      0.691 ms |        9 | avg:  125.655 ms | max:  271.306 ms |
 firefox:5080          |      0.924 ms |        5 | avg:   53.833 ms | max:  257.828 ms |
 npviewer.bin:6225     |     21.871 ms |       53 | avg:   22.462 ms | max:  220.835 ms |
 npviewer.bin:6245     |      9.631 ms |       21 | avg:   41.864 ms | max:  213.349 ms |
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1255012632-7882-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Representing modules as struct map entries, backed by a DSO, etc,
using /proc/modules to find where the module is loaded.

DSOs now can have a short and long name, so that in verbose mode we
can show exactly which .ko or vmlinux image was used.

As kernel modules now are a DSO separate from the kernel, we can
ask for just the hits for a particular set of kernel modules, just
like we can do with shared libraries:

[root@doppio linux-2.6-tip]# perf report -n --vmlinux
/home/acme/git/build/tip-recvmmsg/vmlinux --modules --dsos \[drm\] | head -15
    84.58%      13266             Xorg  [k] drm_clflush_pages
     4.02%        630             Xorg  [k] trace_kmalloc.clone.0
     3.95%        619             Xorg  [k] drm_ioctl
     2.07%        324             Xorg  [k] drm_addbufs
     1.68%        263             Xorg  [k] drm_gem_close_ioctl
     0.77%        120             Xorg  [k] drm_setmaster_ioctl
     0.70%        110             Xorg  [k] drm_lastclose
     0.68%        106             Xorg  [k] drm_open
     0.54%         85             Xorg  [k] drm_mm_search_free
[root@doppio linux-2.6-tip]#

Specifying --dsos /lib/modules/2.6.31-tip/kernel/drivers/gpu/drm/drm.ko
would have the same effect. Allowing specifying just 'drm.ko' is left
for another patch.

Processing kallsyms so that per kernel module struct map are
instantiated was also left for another patch. That will allow
removing the module name from each of its symbols.

struct symbol was reduced by removing the ->module backpointer and
moving it (well now the map) to struct symbol_entry in perf top,
that is its only user right now.

The total linecount went down by ~500 lines.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Threads can have many and kernel modules will be represented as a
tree of maps as well.

Ah, and for a perf.data with 146607 samples:

Before:

[root@doppio ~]# perf stat -r 5 perf report > /dev/null

 Performance counter stats for 'perf report' (5 runs):

     699.823680  task-clock-msecs         #      0.991 CPUs    ( +-   0.454% )
             74  context-switches         #      0.000 M/sec   ( +-   1.709% )
              2  CPU-migrations           #      0.000 M/sec   ( +-  17.008% )
          23114  page-faults              #      0.033 M/sec   ( +-   0.000% )
     1381257019  cycles                   #   1973.721 M/sec   ( +-   0.290% )
     1456894438  instructions             #      1.055 IPC     ( +-   0.007% )
       18779818  cache-references         #     26.835 M/sec   ( +-   0.380% )
         641799  cache-misses             #      0.917 M/sec   ( +-   1.200% )

    0.705972729  seconds time elapsed   ( +-   0.501% )

[root@doppio ~]#

After

 Performance counter stats for 'perf report' (5 runs):

     691.261451  task-clock-msecs         #      0.993 CPUs    ( +-   0.307% )
             72  context-switches         #      0.000 M/sec   ( +-   0.829% )
              6  CPU-migrations           #      0.000 M/sec   ( +-  18.409% )
          23127  page-faults              #      0.033 M/sec   ( +-   0.000% )
     1366395876  cycles                   #   1976.670 M/sec   ( +-   0.153% )
     1443136016  instructions             #      1.056 IPC     ( +-   0.012% )
       17956402  cache-references         #     25.976 M/sec   ( +-   0.325% )
         661924  cache-misses             #      0.958 M/sec   ( +-   1.335% )

    0.696127275  seconds time elapsed   ( +-   0.377% )

I.e. we see some speedup too.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
LKML-Reference: <20090928174846.GA3361@ghostprotocols.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There was a colorful mix of header guards - standardize them.
Signed-off-by: NJohn Kacur <jkacur@redhat.com>
LKML-Reference: <alpine.LFD.2.00.0909241756530.11383@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This prints a textual context-switching outline of workload
captured via perf sched record.

For example, on a 16 CPU box it outputs:

   N1  O1  .   .   .   S1  .   .   .   B0  .  *I0  C1  .   M1  .    23002.773423 secs
   N1  O1  .  *Q0  .   S1  .   .   .   B0  .   I0  C1  .   M1  .    23002.773423 secs
   N1  O1  .   Q0  .   S1  .   .   .   B0  .  *R1  C1  .   M1  .    23002.773485 secs
   N1  O1  .   Q0  .   S1  .  *S0  .   B0  .   R1  C1  .   M1  .    23002.773478 secs
  *L0  O1  .   Q0  .   S1  .   S0  .   B0  .   R1  C1  .   M1  .    23002.773523 secs
   L0  O1  .  *.   .   S1  .   S0  .   B0  .   R1  C1  .   M1  .    23002.773531 secs
   L0  O1  .   .   .   S1  .   S0  .   B0  .   R1  C1 *T1  M1  .    23002.773547 secs T1 => irqbalance:2089
   L0  O1  .   .   .   S1  .   S0  .  *P0  .   R1  C1  T1  M1  .    23002.773549 secs
  *N1  O1  .   .   .   S1  .   S0  .   P0  .   R1  C1  T1  M1  .    23002.773566 secs
   N1  O1  .   .   .  *J0  .   S0  .   P0  .   R1  C1  T1  M1  .    23002.773571 secs
   N1  O1  .   .   .   J0  .   S0 *B0  P0  .   R1  C1  T1  M1  .    23002.773592 secs
   N1  O1  .   .   .   J0  .  *U0  B0  P0  .   R1  C1  T1  M1  .    23002.773582 secs
   N1  O1  .   .   .  *S1  .   U0  B0  P0  .   R1  C1  T1  M1  .    23002.773604 secs
   N1  O1  .   .   .   S1  .   U0  B0 *.   .   R1  C1  T1  M1  .    23002.773615 secs
   N1  O1  .   .   .   S1  .   U0  B0  .   .  *K0  C1  T1  M1  .    23002.773631 secs
   N1  O1  .  *M0  .   S1  .   U0  B0  .   .   K0  C1  T1  M1  .    23002.773624 secs
   N1  O1  .   M0  .   S1  .   U0 *.   .   .   K0  C1  T1  M1  .    23002.773644 secs
   N1  O1  .   M0  .   S1  .   U0  .   .   .  *R1  C1  T1  M1  .    23002.773662 secs
   N1  O1  .   M0  .   S1  .  *.   .   .   .   R1  C1  T1  M1  .    23002.773648 secs
   N1  O1  .  *.   .   S1  .   .   .   .   .   R1  C1  T1  M1  .    23002.773680 secs
   N1  O1  .   .   .  *L0  .   .   .   .   .   R1  C1  T1  M1  .    23002.773717 secs
  *N0  O1  .   .   .   L0  .   .   .   .   .   R1  C1  T1  M1  .    23002.773709 secs
  *N1  O1  .   .   .   L0  .   .   .   .   .   R1  C1  T1  M1  .    23002.773747 secs

Columns stand for individual CPUs, from CPU0 to CPU15, and the
two-letter shortcuts stand for tasks that are running on a CPU.

'*' denotes the CPU that had the event.

A dot signals an idle CPU.

New tasks are assigned new two-letter shortcuts - when they occur
first they are printed. In the above example 'T1' stood for irqbalance:

      T1 => irqbalance:2089

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use a sort list for thread atoms insertion as well - instead of
hardcoded for PID.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Librarize register_idle_thread() used by annotate and report.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1251693921-6579-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Factorize the thread management code used by perf-annotate and
perf-report in dedicated source and header files.

v2: pass last_match by address so that it can actually be
modified.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1250245313-6995-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>