It should just load kernel symbols, not load the list of
modules. There are more stuff to move to other routines, but
lets do it in several steps.

End goal is to be able to defer symbol table loading till we
find a hit for that map address range. So that the kernel &
modules are handled just like all the other DSOs in the system.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1258757489-5978-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

[root@doppio linux-2.6-tip]# perf record -a -f sleep 3s ; perf
buildid-list | grep vmlinux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.171 MB perf.data (~7489
samples) ] 18e7cc53db62a7d35e9d6f6c9ddc23017d38ee9a vmlinux
[root@doppio linux-2.6-tip]#

Several refactorings were needed so that we can have symmetry
between dsos__load_modules() and dsos__load_kernel(), i.e. those
functions will respectively create and add to the dsos list the
loaded modules and kernel, with its buildids, but not load its
symbols. That is something the subcomands that need will have to
call dso__load_kernel_sym(), just like we do with modules with
dsos__load_module_sym()/dso__load_module_sym().

Next csets will actually use this info to stop producing bogus
results using mismatched vmlinux and .ko files.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1258582853-8579-4-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

[root@doppio linux-2.6-tip]# perf record -a sleep 2s;perf
buildid-list|tail [ perf record: Woken up 1 times to write data
] [ perf record: Captured and wrote 0.162 MB perf.data (~7078
samples) ] 881588fa57b3c1696bc91e5e804a11304f093535 [cfg80211]
4d47ce1da9d16bad00c962c072451b7c681e82df [snd_page_alloc]
5146377e89a7caac617f9782f1a02e46263d3a31 [rfkill]
2153b937bff0d345fea83b63a2e1d3138569f83d [i915]
4e6fb1bb97362e3ee4d306988b9ad6912d5fb9ae [drm_kms_helper]
f56ef2bf853e3a798f0d8d51f797622e5dc4420e [drm]
b0d157a3b5c4e017329ffc07c64623cd6ad65e95 [i2c_algo_bit]
8125374b905ef9fa8b65d98e166b008ad952f198 [i2c_core]
fc875c6e5a90e7b915e9d445d0efc859e1b2678c [video]
4b43c5006589f977e9762fdfc7ac1a92b72fca52 [output]
[root@doppio linux-2.6-tip]#

elfutils libdwfl/linux-kernel-modules.c was used as reference,
as suggested by Roland McGrath.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1258582853-8579-3-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

No need for this struct and its allocations, we can just use the
->build_id member we already have in struct dso, then ask for it
to be read, and later traverse the dsos list, writing the
buildid table to the perf.data file.

As a bonus, one more die() function got killed.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1258582853-8579-2-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

When we read the build_id from the DSO name to then index into
/usr/lib/debug/.buildid/DSO_BUILD_ID[0:2]/DSO_BUILD_ID[2:], we
were jumping directly to the comparision with the buildid we
already have in dso->build_id (that came from the perf.data
build_id section, collected at perf record time)
unconditionally, even if we didn't had recorded it, and
furthermore, comparing a formatted buildid with a rawbuildid, yikes.

Fix it by deleting the dso__read_build_id() function, that was
really misdesigned anyway, and do the necessary checks and
correct comparison of raw buildids.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1258582853-8579-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Using a two bytes hole we already had and since we also need to
calculate this strlen for fetching the buildids. We'll use it in
'perf top' to auto-adjust the output based on the terminal
width.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1258479655-28662-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Symbol offset history table size does not get updated properly
when it is being resized. This leads to garbage results in
perf annotate.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Porcelain can ignore it, humans can make more sense of it.
Suggested-by: NFrederic Weisbecker <fweisbec@gmail.com>
Suggested-by: NIngo Molnar <mingo@elte.hu>
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258415125-15019-2-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To print the buildids in the list of dsos. Will be used by 'perf
buildid-list'
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258396365-29217-4-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We need to pass the symbol to the filter so that, for instance,
'perf top' can do filtering and also set the private area it
manages, setting the ->map pointer, etc.

I found this while running 'perf top' on a machine where hits
happened on PLT symbols, where ->map wasn't being set up and
segfaults thus happened.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1258386491-20278-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We are saving the build id once we stop the profiling. And only
after doing that we know if we need to set that feature in the
header through the feature bitmap.

But if we want a proper feature support in the headers, using a
rule of offset/size pairs in sections, we need to know in
advance how many features we need to set in the headers, so that
we can reserve rooms for their section headers.

The current state doesn't allow that, as it forces us to first
save the build-ids to the file right after the datas instead of
planning any structured layout.

That's why this splits up the build-ids processing in two parts:
one that fetches the build-ids from the Dso objects, and one
that saves them into the file.
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>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
LKML-Reference: <1257911467-28276-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With this change 'perf record' will intercept PERF_RECORD_MMAP
calls, creating a linked list of DSOs, then when the session
finishes, it will traverse this list and read the buildids,
stashing them at the end of the file and will set up a new
feature bit in the header bitmask.

'perf report' will then notice this feature and populate the
'dsos' list and set the build ids.

When reading the symtabs it will refuse to load from a file that
doesn't have the same build id. This improves the
reliability of the profiler output, as symbols and profiling
data is more guaranteed to match.

Example:

 [root@doppio ~]# perf report | head
 /home/acme/bin/perf with build id b1ea544ac3746e7538972548a09aadecc5753868 not found, continuing without symbols
  # Samples: 2621434559
  #
  # Overhead          Command                  Shared Object  Symbol
  # ........  ...............  .............................  ......
  #
       7.91%             init  [kernel]        [k] read_hpet
       7.64%             init  [kernel]        [k] mwait_idle_with_hints
       7.60%          swapper  [kernel]        [k] read_hpet
       7.60%          swapper  [kernel]        [k] mwait_idle_with_hints
       3.65%             init  [kernel]        [k] 0xffffffffa02339d9
[root@doppio ~]#

In this case the 'perf' binary was an older one, vanished,
so its symbols probably wouldn't match or would cause subtly
different (and misleading) output.

Next patches will support the kernel as well, reading the build
id notes for it and the modules from /sys.

Another patch should also introduce a new plumbing command:

'perf list-buildids'

that will then be used in porcelain that is distro specific to
fetch -debuginfo packages where such buildids are present. This
will in turn allow for one to run 'perf record' in one machine
and 'perf report' in another.

Future work on having the buildid sent directly from the kernel
in the PERF_RECORD_MMAP event is needed to close races, as the
DSO can be changed during a 'perf record' session, but this
patch at least helps with non-corner cases and current/older
kernels.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K. Prasad <prasad@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1257367843-26224-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So that we can run it without having a DSO instance.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1257291970-8208-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Brown paper bag bug introduced in:

 66bd8424 ("perf tools: Delay
 loading symtabs till we hit a map with it")

Without this we were not loading any symtabs that happened to be
on a DSO for which the allocated memory for ->loaded was !0.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1257270738-5669-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Before we were storing this in the DSO, but in fact this is a
property of the 'symbol' class, not something that will vary
among DSOs, so move it to a global variable and initialize it
using the existing symbol__init routine.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256927305-4628-2-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256927305-4628-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So that we can have a quicker start on perf top and even
speedups in the other tools, as we can have maps with no hits,
so no need to load its symtabs.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256773881-4191-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The Makefile now automatically defines LIBELF_NO_MMAP when
libelf 0.8.x is detected. libelf 0.8 is still maintained and
some distributions such as Arch Linux use it instead of
elfutils.
Signed-off-by: NMarti Raudsepp <marti@juffo.org>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256400636.3007.16.camel@newn>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We were using eprintf in some places, that looks at a global
'verbose' level, and at other places passing a 'v' parameter to
specify the verbosity level, unify it by introducing
pr_{err,warning,debug,etc}, just like in the kernel.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256153646-10097-1-git-send-email-acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We have this sym_priv_size mechanism for attaching private areas
to struct symbol entries but annotate wasn't using it, adding
private areas to struct symbol in addition to a ->priv pointer.

Scrap all that and use the sym_priv_size mechanism.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256055940-19511-1-git-send-email-acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We need this because we get section relative addresses when
reading the symtabs, but when a tool like 'perf annotate' needs
to match these address to what 'objdump -dS' produces we need
the address + section back again.

So in annotate now we look at the 'struct hist_entry' instances
(that weren't really being used) so that we iterate only over
the symbols that had some hit and get the map where that
particular hit happened so that we can get the right address to
match with annotate.

Verified that at least:

 perf annotate mmap_read_counter # Uses the ~/bin/perf binary
 perf annotate --vmlinux /home/acme/git/build/perf/vmlinux intel_pmu_enable_all

on a 'perf record perf top' session seems to work.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1255979877-12533-1-git-send-email-acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This removes the ovelapping of vmlinux addresses with modules,
using the ELF section name when using --vmlinux and creating a
unique DSO name when using /proc/kallsyms ([kernel].N).

This is done by creating multiple 'struct map' instances for
address ranges backed by DSOs that have just the symbols for that
range and a name that is derived from the ELF section name.o

Now it is possible to ask for just the symbols in some particular
kernel section:

$ perf report -m --vmlinux ../build/tip-recvmmsg/vmlinux \
	--dsos [kernel].vsyscall_fn | head -15
    52.73%             Xorg  [.] vread_hpet
    18.61%          firefox  [.] vread_hpet
    14.50%     npviewer.bin  [.] vread_hpet
     6.83%           compiz  [.] vread_hpet
     5.73%         glxgears  [.] vread_hpet
     0.63%             java  [.] vread_hpet
     0.30%   gnome-terminal  [.] vread_hpet
     0.23%             perf  [.] vread_hpet
     0.18%            xchat  [.] vread_hpet
$

Now we don't have to first lookup the list of modules and then, if
it fails, vmlinux symbols, its just a simple lookup for the map
then the symbols, just like for threads.

Reports generated using /proc/kallsyms and --vmlinux should provide
the same results, modulo the DSO name for sections other than
".text".

But they don't right now because things like:

 ffffffff81011c20-ffffffff81012068 system_call
 ffffffff81011c30-ffffffff81011c9b system_call_after_swapgs
 ffffffff81011c9c-ffffffff81011cb6 system_call_fastpath
 ffffffff81011cb7-ffffffff81011cbb ret_from_sys_call

I.e. overlapping symbols, again some ASM special case that we have
to fixup.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1254934136-8503-1-git-send-email-acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Like printing every symbol created.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1254923340-4870-1-git-send-email-acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Asm routines that end up having size equal to zero are not really
zero sized, and as now we do kernel_maps__fixup_sym_end, at least
for kernel routines this gets fixed.

A similar fixup needs to be done for the userspace bits as well,
but as this fixup started only because in /proc/kallsyms we don't
have the end address nor the function size, it appeared here first.
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>
LKML-Reference: <1254796503-27203-1-git-send-email-acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

$ cut -d' ' -f1 /proc/modules|grep _|wc -l
 29
 $ cut -d' ' -f1 /proc/modules|grep _|sed 's/$/.ko'/g|while read n;do find /lib/modules/`uname -r` -name $n;done|wc -l
 12

For instance:

 $ grep ^aes_x86 /proc/modules
 aes_x86_64 9056 2 - Live 0xffffffffa0091000
 $ l /lib/modules/2.6.31-tip/kernel/arch/x86/crypto/aes-x86_64.ko
 -rw-r--r-- 1 root root 136438 2009-09-22 19:05 /lib/modules/2.6.31-tip/kernel/arch/x86/crypto/aes-x86_64.ko

Handle that by introducing a strxfrchar routine that replaces
dashes with underscores when matching file names to loaded modules.
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>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So that we get kallsyms processing closer to vmlinux + modules
symtabs processing.

One change in behaviour is that since when one specifies --vmlinux
-m should be used to ask for modules, so it is now for kallsyms as
well.

Also continue if one manages to load the vmlinux data but module
processing fails, so that at least some analisys can be done with
part of the needed symbols.
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>
LKML-Reference: <new-submission>
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>

Avi Kivity reported 'perf annotate' failures with modules, the
requested function was not annotated.

If there are no modules currently loaded, or the last module
scanned is not loaded, dso__load_modules() steps on the value from
dso__load_vmlinux(), so we happily load the kallsyms symbols on top
of what we've already loaded.

Fix that such that the total count of symbols loaded is returned.
Should module symbol load fail after parsing of vmlinux, is's a
hard failure, so do not silently fall-back to kallsyms.
Reported-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NMike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: rostedt@goodmis.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <1253697658.11461.36.camel@marge.simson.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Librarize trace_event() helper so that perf trace can use it
too. Also clean up the debug.h includes a bit.

It's not good to have it included in perf.h because it doesn't
make it flexible against other headers it may need (headers
that can also depend on perf.h and then create a recursive
header dependency).
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>
LKML-Reference: <1250453149-664-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Related to a shadowed variable bug fix Valdis Kletnieks noticed
that perf does not get built with -Wshadow, which could have
helped us avoid the bug.

So enable -Wshadow and also enable the following warnings on
perf builds, in addition to the already enabled -Wall -Wextra
-std=gnu99 warnings:

 -Wcast-align
 -Wformat=2
 -Wshadow
 -Winit-self
 -Wpacked
 -Wredundant-decls
 -Wstack-protector
 -Wstrict-aliasing=3
 -Wswitch-default
 -Wswitch-enum
 -Wno-system-headers
 -Wundef
 -Wvolatile-register-var
 -Wwrite-strings
 -Wbad-function-cast
 -Wmissing-declarations
 -Wmissing-prototypes
 -Wnested-externs
 -Wold-style-definition
 -Wstrict-prototypes
 -Wdeclaration-after-statement

And change/fix the perf code to build cleanly under GCC 4.3.2.

The list of warnings enablement is rather arbitrary: it's based
on my (quick) reading of the GCC manpages and trying them on
perf.

I categorized the warnings based on individually enabling them
and looking whether they trigger something in the perf build.
If i liked those warnings (i.e. if they trigger for something
that arguably could be improved) i enabled the warning.

If the warnings seemed to come from language laywers spamming
the build with tons of nuisance warnings i generally kept them
off. Most of the sign conversion related warnings were in
this category. (A second patch enabling some of the sign
warnings might be welcome - sign bugs can be nasty.)

I also kept warnings that seem to make sense from their manpage
description and which produced no actual warnings on our code
base. These warnings might still be turned off if they end up
being a nuisance.

I also left out a few warnings that are not supported in older
compilers.

[ Note that these changes might break the build on older
  compilers i did not test, or on non-x86 architectures that
  produce different warnings, so more testing would be welcome. ]

Reported-by: Valdis.Kletnieks@vt.edu
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>

It is better than showing the map addr, this way at least we
know that we can't get the symtabs because the DSO was deleted
(system update) while an app still used such DSO.

Yeah, don't do that, but if you do, you'll figure it out
quicker this way.

[acme@doppio linux-2.6-tip]$ perf report | head -15
 # Samples: 3796
 #
 # Overhead  Command                                                        Shared Object  Symbol
 # ........  .......  ...................................................................  ......
 #
    23.55%   pidgin  /lib64/libglib-2.0.so.0.2000.4.#prelink#.Pd98lu (deleted)            [.] 0x00000000038844
    21.55%   pidgin  /lib64/libpthread-2.10.1.so.#prelink#.AFwK8Q (deleted)               [.] 0x0000000000a42d
    10.85%   pidgin  [kernel]                                                             [.] vread_hpet
     7.85%   pidgin  /lib64/libgobject-2.0.so.0.2000.4.#prelink#.o1vpU7 (deleted)         [.] 0x00000000014de8
     3.35%   pidgin  /lib64/libc-2.10.1.so (deleted)                                      [.] 0x0000000007a875
     3.19%   pidgin  /lib64/libdbus-1.so.3.4.0.#prelink#.6mwgZP (deleted)                 [.] 0x0000000001d254
     3.06%   pidgin  /usr/lib64/libgtk-x11-2.0.so.0.1600.5.#prelink#.511hAl (deleted)     [.] 0x000000002334e7
     2.90%   pidgin  /usr/lib64/libgdk-x11-2.0.so.0.1600.5.#prelink#.5qlMo1 (deleted)     [.] 0x00000000037b2d
     1.84%   pidgin  [kernel]                                                             [k] do_sys_poll
     1.45%   pidgin  /usr/lib64/libX11.so.6.2.0.#prelink#.iR59Rx (deleted)                [.] 0x0000000004c751
[acme@doppio linux-2.6-tip]$
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Luis Claudio R. Gonçalves <lclaudio@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090811200436.GA3478@ghostprotocols.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In old binutils we can't access bfd_demangle(), use
cplus_demangle() just like oprofile.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Luis Claudio R. Gonçalves <lclaudio@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090811192211.GG18061@ghostprotocols.net>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Factorize multiple definitions of high level dso helpers into the
symbol source file.

The side effect is a general export of the verbose and eprintf
debugging helpers into a new file dedicated to debugging purposes.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Brice Goglin <Brice.Goglin@inria.fr>

perf report: Add debug help for the finding of symbol bugs - show the symtab origin (DSO, build-id, kernel, etc)

Used with perf report --verbose:

[acme@doppio linux-2.6-tip]$ perf report -v | head -16
     5.17%  firefox  /usr/lib64/xulrunner-1.9.1/libxul.so   0x00000000005d8eee f [.] imgContainer::DrawFrameTo(gfxIImageFrame*, gfxIImageFrame*, nsRect&)
     2.56%  firefox  /lib64/libpthread-2.10.1.so            0x0000000000008e02 d [.] __pthread_mutex_lock_internal
     1.94%  firefox  /usr/lib64/xulrunner-1.9.1/libxul.so   0x0000000000d0af8f f [.] SearchTable
     1.75%  firefox  [kernel]                               0xffffffffff60013b k [.] vread_hpet
     1.63%  firefox  /lib64/libpthread-2.10.1.so            0x000000000000a404 d [.] __pthread_mutex_unlock
     1.47%  firefox  /usr/lib64/xulrunner-1.9.1/libmozjs.so 0x00000000000482ea f [.] js_Interpret
     1.42%  firefox  /usr/lib64/xulrunner-1.9.1/libmozjs.so 0x000000000003eda3 f [.] JS_CallTracer
     1.24%  firefox  [kernel]                               0xffffffff8102ca4a k [k] read_hpet
     1.16%  firefox  [kernel]                               0xffffffff810f3dd4 k [k] fget_light
     1.11%  firefox  /usr/lib64/xulrunner-1.9.1/libmozjs.so 0x00000000000567ff f [.] js_TraceObject
     0.98%  firefox  /usr/lib64/firefox-3.5.2/firefox       0x000000000000dd23 b [.] arena_ralloc
[acme@doppio linux-2.6-tip]$

The new field is just after the symbol address. To help in
figuring out symbol resolution bugs.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In some cases distros have binaries and debuginfo in weird places:

[root@doppio tuna]# ls -la /usr/lib64/{xulrunner-1.9.1/xulrunner-stub,firefox-3.5.2/firefox}
-rwxr-xr-x 1 root root 90024 2009-08-03 19:45 /usr/lib64/firefox-3.5.2/firefox
-rwxr-xr-x 1 root root 90024 2009-08-03 18:23 /usr/lib64/xulrunner-1.9.1/xulrunner-stub
[root@doppio tuna]# sha1sum /usr/lib64/{xulrunner-1.9.1/xulrunner-stub,firefox-3.5.2/firefox}
19a858077d263d5de22c9c5da250d3e4396ae739  /usr/lib64/xulrunner-1.9.1/xulrunner-stub
19a858077d263d5de22c9c5da250d3e4396ae739  /usr/lib64/firefox-3.5.2/firefox
[root@doppio tuna]# rpm -qf /usr/lib64/{xulrunner-1.9.1/xulrunner-stub,firefox-3.5.2/firefox}
xulrunner-1.9.1.2-1.fc11.x86_64
firefox-3.5.2-2.fc11.x86_64
[root@doppio tuna]# ls -la /usr/lib/debug/{usr/lib64/xulrunner-1.9.1/xulrunner-stub,usr/lib64/firefox-3.5.2/firefox}.debug
ls: cannot access /usr/lib/debug/usr/lib64/firefox-3.5.2/firefox.debug: No such file or directory
-rwxr-xr-x 1 root root 403608 2009-08-03 18:22 /usr/lib/debug/usr/lib64/xulrunner-1.9.1/xulrunner-stub.debug

Seemingly we don't have a .symtab when we actually can find it
if we use the .note.gnu.build-id ELF section put in place by
some distros. Use it and find the symbols we need.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Since the C++ demangling isn't needed for everybody and
bfd/iberty aren't widely/easily available on all machines, make
it optional.

It also allows you to forcefully disable demangling by using
NO_DEMANGLE=1 and otherwise tries to detect libbfd/libiberty
combinations that result in a compiling demangler.
Reported-by: NJens Axboe <jens.axboe@oracle.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
LKML-Reference: <20090801082048.GX12579@kernel.dk>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch fixes a spelling error that has resulted from copy
and pasting. The location of the error was found using a
semantic patch but the semantic patch was not trying to find
these errors. After looking things over it seemed logical that
this change was needed. Please review it and then include the
patch if it is in fact the correct change.
Signed-off-by: NStoyan Gaydarov <sgayda2@uiuc.edu>
Signed-off-by: NPeter 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: <1248949529-20891-1-git-send-email-sgayda2@uiuc.edu>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

vmlinux meets the criteria for symbol adjustment, which breaks vmlinux generated symbols.
Fix this by exempting vmlinux.  This is a bit fragile in that someone could change the
kernel dso's name, but currently that name is also hardwired.
Signed-off-by: NMike Galbraith <efault@gmx.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248091298.18702.18.camel@marge.simson.net>

[acme@doppio ~]$ perf report -s comm,dso,symbol -C firefox -d /usr/lib64/xulrunner-1.9.1/libxul.so | grep :: | head
     2.21%  [.] nsDeque::Push(void*)
     1.78%  [.] GraphWalker::DoWalk(nsDeque&)
     1.30%  [.] GCGraphBuilder::AddNode(void*, nsCycleCollectionParticipant*)
     1.27%  [.] XPCWrappedNative::CallMethod(XPCCallContext&, XPCWrappedNative::CallMode)
     1.18%  [.] imgContainer::DrawFrameTo(gfxIImageFrame*, gfxIImageFrame*, nsRect&)
     1.13%  [.] nsDeque::PopFront()
     1.11%  [.] nsGlobalWindow::RunTimeout(nsTimeout*)
     0.97%  [.] nsXPConnect::Traverse(void*, nsCycleCollectionTraversalCallback&)
     0.95%  [.] nsJSEventListener::cycleCollection::Traverse(void*, nsCycleCollectionTraversalCallback&)
     0.95%  [.] nsCOMPtr_base::~nsCOMPtr_base()
[acme@doppio ~]$

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Suggested-by: NClark Williams <williams@redhat.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090720171412.GB10410@ghostprotocols.net>

So we need to get the richer .symtab from the debuginfo
packages but the PLT info from the original DSO where we have
just the leaner .dynsym symtab.

Example:

| [acme@doppio pahole]$ perf report --sort comm,dso,symbol > before
| [acme@doppio pahole]$ perf report --sort comm,dso,symbol > after
| [acme@doppio pahole]$ diff -U1 before after
| --- before	2009-07-11 11:04:22.688595741 -0300
| +++ after	2009-07-11 11:04:33.380595676 -0300
| @@ -80,3 +80,2 @@
|       0.07%  pahole ./build/pahole              [.] pahole_stealer
| -     0.06%  pahole /usr/lib64/libdw-0.141.so   [.] 0x00000000007140
|       0.06%  pahole /usr/lib64/libdw-0.141.so   [.] __libdw_getabbrev
| @@ -91,2 +90,3 @@
|       0.06%  pahole [kernel]                    [k] free_hot_cold_page
| +     0.06%  pahole /usr/lib64/libdw-0.141.so   [.] tfind@plt
|       0.05%  pahole ./build/libdwarves.so.1.0.0 [.] ftype__add_parameter
| @@ -242,2 +242,3 @@
|       0.01%  pahole [kernel]                    [k] account_group_user_time
| +     0.01%  pahole /usr/lib64/libdw-0.141.so   [.] strlen@plt
|       0.01%  pahole ./build/pahole              [.] strcmp@plt
| [acme@doppio pahole]$
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1247325517-12272-4-git-send-email-acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>