Commit Graph

107 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
a19afe4641 perf symbols: Factor out dso__load_vmlinux_path()
So that we can call it directly from regression tests, and also
to reduce the size of dso__load_kernel_sym(), making it more
clear.

Signed-off-by: Arnaldo 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: <1264633557-17597-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-29 09:20:57 +01:00
Arnaldo Carvalho de Melo
19fc2dedff perf symbols: Use the right variable to check for kallsyms in the cache
Probably this wasn't noticed when testing this on my parisc
machine because I must have copied manually to its cache the
vmlinux file used in the x86_64 machine, now that I tried
looking on a x86-32 machine with a fresh cache, kernel symbols
weren't being resolved even with the right kallsyms copy on its
cache, duh.

Signed-off-by: Arnaldo 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: <1264178102-4203-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-27 12:46:49 +01:00
Arnaldo Carvalho de Melo
e1c7c6a40c perf symbols: Fix inverted logic for showing kallsyms as the source of symbols
Only if we parsed /proc/kallsyms (or a copy found in the buildid
cache) we should set the dso long name to "[kernel.kallsyms]".

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Arnaldo 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: <1264178102-4203-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-27 12:46:49 +01:00
Arnaldo Carvalho de Melo
ef12a14130 perf buildid-cache: Add new command to manage build-id cache
For now it just has operations to examine a given file, find its
build-id and add or remove it to/from the cache.

Useful, for instance, when adding binaries sent together with a
perf.data file, so that we can add them to the cache and have
the tools find it when resolving symbols.

It'll also manage the size of the cache like 'ccache' does.

Signed-off-by: Arnaldo 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: <1264008525-29025-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-21 08:31:29 +01:00
Arnaldo Carvalho de Melo
dc8d6ab2b6 perf symbols: Use only --vmlinux if specified
Found while analysing a perf.data file collected on an ARM
machine where an explicitely specified vmlinux was being
disregarded.

Reported-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Arnaldo 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: <1263904574-30732-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-20 08:55:00 +01:00
Arnaldo Carvalho de Melo
88d3d9b7c8 perf buildid-list: Introduce --with-hits option
Using this option 'perf buildid-list' will process all samples,
marking the DSOs that had some hits to list just them.

This in turn will be used by a new porcelain, 'perf archive',
that will be just a shell script to create a tarball from the
'perf buildid-list --with-hits' output and the files cached by
'perf record' in ~/.debug.

Signed-off-by: Arnaldo 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: <1263519930-22803-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16 10:58:49 +01:00
Arnaldo Carvalho de Melo
cf4e5b0838 perf symbols: Use dso->long_name in dsos__find()
If not we end up duplicating the module DSOs because first we
insert them using the short name found in /proc/modules, then,
when processing synthesized MMAP events we add them again.

Signed-off-by: Arnaldo 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: <1263519930-22803-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16 10:58:47 +01:00
Arnaldo Carvalho de Melo
9e201442de perf symbols: Cache /proc/kallsyms files by build-id
So that when we don't have a vmlinux handy we can store the
kallsyms for later use by 'perf report'.

Signed-off-by: Arnaldo 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: <1263501006-14185-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16 10:58:47 +01:00
Arnaldo Carvalho de Melo
8d0591f6ad perf symbols: Don't try to load kallsyms if doesn't match the record build-id
Now a perf.data file collected on a x86_64 fedora 12 machine
gets properly parsed on a Debian testing PARISC64 machine with
32-bit userland:

  acme@parisc:~/git/linux-2.6-tip$ perf report 2> /dev/null | head -15
  # Samples: 293085637
  #
  # Overhead          Command                      Shared Object  Symbol
  # ........  ...............  .................................  ......
  #
      35.11%             find  [kernel.kallsyms]                  [k] 0xffffffff81002b5a
      18.25%             perf  [kernel.kallsyms]                  [k] 0xffffffff8102235f
       9.07%             find  find                               [.] 0x0000000000fb0e
       5.80%          swapper  [kernel.kallsyms]                  [k] 0xffffffff8102235f
       3.29%             perf  libc-2.10.2.so                     [.] __GI_strcmp
       2.70%             find  libc-2.10.2.so                     [.] __GI_memmove
       2.33%             init  [kernel.kallsyms]                  [k] 0xffffffff810091b9
       2.03%             find  libc-2.10.2.so                     [.] _int_malloc
       1.67%             find  libc-2.10.2.so                     [.] _IO_vfprintf_internal
       1.65%             sshd  libcrypto.so.0.9.8k                [.] 0x00000000105440
  acme@parisc:~/git/linux-2.6-tip$

Signed-off-by: Arnaldo 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: <1263501006-14185-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-16 10:58:46 +01:00
Arnaldo Carvalho de Melo
b7cece7678 perf tools: Encode kernel module mappings in perf.data
We were always looking at the running machine /proc/modules,
even when processing a perf.data file, which only makes sense
when we're doing 'perf record' and 'perf report' on the same
machine, and in close sucession, or if we don't use modules at
all, right Peter? ;-)

Now, at 'perf record' time we read /proc/modules, find the long
path for modules, and put them as PERF_MMAP events, just like we
did to encode the reloc reference symbol for vmlinux. Talking
about that now it is encoded in .pgoff, so that we can use
.{start,len} to store the address boundaries for the kernel so
that when we reconstruct the kmaps tree we can do lookups right
away, without having to fixup the end of the kernel maps like we
did in the past (and now only in perf record).

One more step in the 'perf archive' direction when we'll finally
be able to collect data in one machine and analyse in another.

Signed-off-by: Arnaldo 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: <1263396139-4798-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 17:39:43 +01:00
Arnaldo Carvalho de Melo
a89e5abe3e perf symbols: Record the domain of DSOs in HEADER_BUILD_ID header table
So that we can restore them to the right DSO list (either
dsos__kernel or dsos__user).

We do that just like the kernel does for the other events,
encoding PERF_RECORD_MISC_{KERNEL,USER} in perf_event_header.

Signed-off-by: Arnaldo 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: <1262901583-8074-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 10:09:16 +01:00
Arnaldo Carvalho de Melo
56b03f3c4d perf tools: Handle relocatable kernels
DSOs don't have this problem because the kernel emits a
PERF_MMAP for each new executable mapping it performs on
monitored threads.

To fix the kernel case we simulate the same behaviour, by having
'perf record' to synthesize a PERF_MMAP for the kernel, encoded
like this:

[root@doppio ~]# perf record -a -f sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.344 MB perf.data (~15038 samples) ]
[root@doppio ~]# perf report -D | head -10

0xd0 [0x40]: event: 1
.
. ... raw event: size 64 bytes
.  0000:  01 00 00 00 00 00 40 00 00 00 00 00 00 00 00 00 ......@........
.  0010:  00 00 00 81 ff ff ff ff 00 00 00 00 00 00 00 00 ...............
.  0020:  00 00 00 00 00 00 00 00 5b 6b 65 72 6e 65 6c 2e ........  [kernel
.  0030:  6b 61 6c 6c 73 79 6d 73 2e 5f 74 65 78 74 5d 00  kallsyms._text]
.  0xd0
[0x40]: PERF_RECORD_MMAP 0/0: [0xffffffff81000000((nil)) @ (nil)]: [kernel.kallsyms._text]

I.e. we identify such event as having:

 .pid      = 0
 .filename = [kernel.kallsyms.REFNAME]
 .start    = REFNAME addr in /proc/kallsyms at 'perf record' time

and use now a hardcoded value of '.text' for REFNAME.

Then, later, in 'perf report', if there are any kernel hits and
thus we need to resolve kernel symbols, we search for REFNAME
and if its address changed, relocation happened and we thus must
change the kernel mapping routines to one that uses .pgoff as
the relocation to apply.

This way we use the same mechanism used for the other DSOs and
don't have to do a two pass in all the kernel symbols.

Reported-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
LKML-Reference: <1262717431-1246-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 10:09:11 +01:00
Arnaldo Carvalho de Melo
de1764892a perf session: Keep pointers to the vmlinux maps
So that tools such as 'perf probe' don't have to lookup
'[kernel.kallsyms]' but instead access them directly after
perf_session__create_kernel_maps or
map_groups__create_kernel_maps.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Masami Hiramatsu <mhiramat@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: <1262629169-22797-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 10:09:10 +01:00
Arnaldo Carvalho de Melo
36a3e6461a perf symbols: Export symbol_type__is_a
Will be needed by the new HEADER_DSO_INFO feature that will be a
HEADER_BUILD_ID superset, replacing it.

Signed-off-by: Arnaldo 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: <1262629169-22797-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 10:09:09 +01:00
Arnaldo Carvalho de Melo
682b335a5b perf symbols: Generalise the kallsyms parsing routine
Will be used to find an specific symbol by name on 'perf record'
to support relocation reference symbols to support relocatable
kernels.

Still have to conver the perf trace tools to use it instead of
their current reimplementation.

Signed-off-by: Arnaldo 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: <1262629169-22797-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 10:09:08 +01:00
Arnaldo Carvalho de Melo
4cf40131a5 perf record: Introduce a symtab cache
Now a cache will be created in a ~/.debug debuginfo like
hierarchy, so that at the end of a 'perf record' session all the
binaries (with build-ids) involved get collected and indexed by
their build-ids, so that perf report can find them.

This is interesting when developing software where you want to
do a 'perf diff' with the previous build and opens avenues for
lots more interesting tools, like a 'perf diff --graph' that
takes more than two binaries into account.

Tunables for collecting just the symtabs can be added if one
doesn't want to have the full binary, but having the full binary
allows things like 'perf rerecord' or other tools that can
re-run the tests by having access to the exact binary in some
perf.data file, so it may well be interesting to keep the full
binary there.

Space consumption is minimised by trying to use hard links, a
'perf cache' tool to manage the space used, a la ccache is
required to purge older entries.

With this in place it will be possible also to introduce new
commands, 'perf archive' and 'perf restore' (or some more
suitable and future proof names) to create a cpio/tar file with
the perf data and the files in the cache that _had_ perf hits of
interest.

There are more aspects to polish, like finding the right vmlinux
file to cache, etc, but this is enough for a first step.

Signed-off-by: Arnaldo 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: <1261957026-15580-10-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-28 09:03:36 +01:00
Arnaldo Carvalho de Melo
d599db3fc5 perf report: Generalize perf_session__fprintf_hists()
Pull it out of builtin-report - further changes will be made and it
will then be reusable in 'perf diff' as well.

Signed-off-by: Arnaldo 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: <1260914682-29652-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16 08:53:50 +01:00
Arnaldo Carvalho de Melo
c410a33887 perf symbols: Move symbol filtering to event__preprocess_sample()
So that --dsos, --comm, --symbols can bem used in more tools,
like in perf diff:

$ perf record -f find / > /dev/null
$ perf record -f find / > /dev/null
$ perf diff --dsos /lib64/libc-2.10.1.so | head -5
   1        +22392124     /lib64/libc-2.10.1.so   _IO_vfprintf_internal
   2         +6410655     /lib64/libc-2.10.1.so   __GI_memmove
   3    +1   +9192692     /lib64/libc-2.10.1.so   _int_malloc
   4    -1  -15158605     /lib64/libc-2.10.1.so   _int_free
   5           +45669     /lib64/libc-2.10.1.so   _IO_new_file_xsputn
$

Signed-off-by: Arnaldo 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: <1260914682-29652-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16 08:53:49 +01:00
Arnaldo Carvalho de Melo
655000e7c7 perf symbols: Adopt the strlists for dso, comm
Will be used in perf diff too.

Signed-off-by: Arnaldo 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: <1260914682-29652-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16 08:53:49 +01:00
Arnaldo Carvalho de Melo
75be6cf487 perf symbols: Make symbol_conf global
This simplifies a lot of functions, less stuff to be done by
tool writers.

Signed-off-by: Arnaldo 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: <1260914682-29652-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16 08:53:48 +01:00
Arnaldo Carvalho de Melo
4aa6563641 perf session: Move kmaps to perf_session
There is still some more work to do to disentangle map creation
from DSO loading, but this happens only for the kernel, and for
the early adopters of perf diff, where this disentanglement
matters most, we'll be testing different kernels, so no problem
here.

Further clarification: right now we create the kernel maps for
the various modules and discontiguous kernel text maps when
loading the DSO, we should do it as a two step process, first
creating the maps, for multiple mappings with the same DSO
store, then doing the dso load just once, for the first hit on
one of the maps sharing this DSO backing store.

Signed-off-by: Arnaldo 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: <1260741029-4430-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-14 16:57:17 +01:00
Arnaldo Carvalho de Melo
ea08d8cbd1 perf symbols: Ditch dso->find_symbol
It is always wired to dso__find_symbol.

Signed-off-by: Arnaldo 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: <1260564999-13371-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12 07:42:11 +01:00
Arnaldo Carvalho de Melo
79406cd789 perf symbols: Allow lookups by symbol name too
Configurable via symbol_conf.sort_by_name, so that the cost of an
extra rb_node on all 'struct symbol' instances is not paid by tools
that only want to decode addresses.

How to use it:

	symbol_conf.sort_by_name = true;
	symbol_init(&symbol_conf);

	struct map *map = map_groups__find_by_name(kmaps, MAP__VARIABLE, "[kernel.kallsyms]");

	if (map == NULL) {
		pr_err("couldn't find map!\n");
		kernel_maps__fprintf(stdout);
	} else {
		struct symbol *sym = map__find_symbol_by_name(map, sym_filter, NULL);
		if (sym == NULL)
			pr_err("couldn't find symbol %s!\n", sym_filter);
		else
			pr_info("symbol %s: %#Lx-%#Lx \n", sym_filter, sym->start, sym->end);
	}

Looking over the vmlinux/kallsyms is common enough that I'll add a
variable to the upcoming struct perf_session to avoid the need to
use map_groups__find_by_name to get the main vmlinux/kallsyms map.

The above example looks on the 'variable' symtab, but it is just
like that for the functions one.

Also the sort operation is done when we first use
map__find_symbol_by_name, in a lazy way.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260564622-12392-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12 07:42:11 +01:00
Arnaldo Carvalho de Melo
f1dfa0b1c1 perf symbols: Add support for 'variable' symtabs
Example:

{
	u64 addr = strtoull(sym_filter, NULL, 16);
	struct map *map = map_groups__find(kmaps, MAP__VARIABLE, addr);

	if (map == NULL)
		pr_err("couldn't find map!\n");
	else {
		struct symbol *sym = map__find_symbol(map, addr, NULL);
		if (sym == NULL)
			pr_err("couldn't find addr!\n");
		else
			pr_info("addr %#Lx is in %s global var\n", addr, sym->name);
	}
	exit(0);
}

Added just after symbol__init() call in 'perf top', then:

{
        u64 addr = strtoull(sym_filter, NULL, 16);
        struct map *map = map_groups__find(kmaps, MAP__VARIABLE, addr);

        if (map == NULL)
                pr_err("couldn't find map!\n");
        else {
                struct symbol *sym = map__find_symbol(map, addr, NULL);
                if (sym == NULL)
                        pr_err("couldn't find addr!\n");
                else
                        pr_info("addr %#Lx is in %s global var\n", addr, sym->name);
        }
        exit(0);
}

[root@doppio linux-2.6-tip]# grep ' [dD] ' /proc/kallsyms | grep ' sched'
ffffffff817827d8 d sched_nr_latency
ffffffff81782ce0 d sched_domains_mutex
ffffffff8178c070 d schedstr.22423
ffffffff817909a0 d sched_register_mutex
ffffffff81823490 d sched_feat_names
ffffffff81823558 d scheduler_running
ffffffff818235b8 d sched_clock_running
ffffffff818235bc D sched_clock_stable
ffffffff81824f00 d sched_switch_trace
[root@doppio linux-2.6-tip]# perf top -s 0xffffffff817827d9
addr 0xffffffff817827d9 is in sched_nr_latency global var
[root@doppio linux-2.6-tip]# perf top -s ffffffff81782ce0
addr 0xffffffff81782ce0 is in sched_domains_mutex global var
[root@doppio linux-2.6-tip]#
[root@doppio linux-2.6-tip]# perf top -s ffffffff81782ce0 --vmlinux OFF
The file OFF cannot be used, trying to use /proc/kallsyms...addr 0xffffffff81782ce0 is in sched_domains_mutex global var
[root@doppio linux-2.6-tip]# perf top -s ffffffff818235bc --vmlinux OFF
The file OFF cannot be used, trying to use /proc/kallsyms...addr 0xffffffff818235bc is in sched_clock_stable global var
[root@doppio linux-2.6-tip]#

So it works with both /proc/kallsyms and with ELF symtabs, either
the one on the vmlinux explicitely passed via --vmlinux or in one
in the vmlinux_path that matches the buildid for the running kernel
or the one found in the buildid header section in a perf.data file.

Signed-off-by: Arnaldo 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: <1260550239-5372-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12 07:42:10 +01:00
Arnaldo Carvalho de Melo
d45868d38c perf symbols: Introduce ELF counterparts to symbol_type__is_a
For selecting the right types of symbols in ELF symtabs.

Signed-off-by: Arnaldo 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: <1260550239-5372-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12 07:42:10 +01:00
Arnaldo Carvalho de Melo
6893d4ee67 perf symbols: Introduce symbol_type__is_a
For selecting the right types of symbols in /proc/kallsyms, will be
followed by elf_symbol_type__is_a, for the same purpose on ELF
symtabs.

Signed-off-by: Arnaldo 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: <1260550239-5372-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12 07:42:09 +01:00
Arnaldo Carvalho de Melo
9958e1f0ae perf symbols: Rename kthreads to kmaps, using another abstraction for it
Using a struct thread instance just to hold the kernel space maps
(vmlinux + modules) is overkill and confuses people trying to
understand the perf symbols abstractions.

The kernel maps are really present in all threads, i.e. the kernel
is a library, not a separate thread.

So introduce the 'map_groups' abstraction and use it for the kernel
maps, now in the kmaps global variable.

It, in turn, will move, together with the threads list to the
perf_file abstraction, so that we can support multiple perf_file
instances, needed by perf diff.

Brainstormed-with: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Eduardo Habkost <ehabkost@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: <1260550239-5372-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-12 07:42:09 +01:00
Arnaldo Carvalho de Melo
8b4825bf8d perf symbols: dsos__read_build_ids() should read both user and kernel buildids
Signed-off-by: Arnaldo 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: <1260396578-19116-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:28 +01:00
Arnaldo Carvalho de Melo
1ed091c45a perf tools: Consolidate symbol resolving across all tools
Now we have a very high level routine for simple tools to
process IP sample events:

	int event__preprocess_sample(const event_t *self,
				     struct addr_location *al,
				     symbol_filter_t filter)

It receives the event itself and will insert new threads in the
global threads list and resolve the map and symbol, filling all
this info into the new addr_location struct, so that tools like
annotate and report can further process the event by creating
hist_entries in their specific way (with or without callgraphs,
etc).

It in turn uses the new next layer function:

	void thread__find_addr_location(struct thread *self, u8 cpumode,
					enum map_type type, u64 addr,
					struct addr_location *al,
					symbol_filter_t filter)

This one will, given a thread (userspace or the kernel kthread
one), will find the given type (MAP__FUNCTION now, MAP__VARIABLE
too in the near future) at the given cpumode, taking vdsos into
account (userspace hit, but kernel symbol) and will fill all
these details in the addr_location given.

Tools that need a more compact API for plain function
resolution, like 'kmem', can use this other one:

	struct symbol *thread__find_function(struct thread *self, u64 addr,
					     symbol_filter_t filter)

So, to resolve a kernel symbol, that is all the 'kmem' tool
needs, its just a matter of calling:

	sym = thread__find_function(kthread, addr, NULL);

The 'filter' parameter is needed because we do lazy
parsing/loading of ELF symtabs or /proc/kallsyms.

With this we remove more code duplication all around, which is
always good, huh? :-)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1259346563-12568-12-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:22:02 +01:00
Arnaldo Carvalho de Melo
1de8e24520 perf symbols: When not using modules, discard its symbols
Signed-off-by: Arnaldo 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: <1259346563-12568-10-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:22:01 +01:00
Arnaldo Carvalho de Melo
95011c6007 perf symbols: Support multiple symtabs in struct thread
Making the routines that were so far specific to the kernel maps
useful for all threads.

This is done by making the kernel maps be contained in a kernel
"thread".

This gets the kernel specific routines closer to the userspace
counterparts, which will help in reducing the boilerplate for
resolving a symbol, as will be demonstrated in the next patches.

Signed-off-by: Arnaldo 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: <1259346563-12568-9-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:22:00 +01:00
Arnaldo Carvalho de Melo
23ea4a3fad perf symbols: Kernel_maps should be an array of MAP__NR_TYPES entries
So that we can support multiple symbol table types.

Signed-off-by: Arnaldo 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: <1259346563-12568-8-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:22:00 +01:00
Arnaldo Carvalho de Melo
4e06255f5c perf symbols: Make the kallsyms loading routines part of the dso class
So that the kallsyms loading routines are the direct counterpart
of the vmlinux loading ones, i.e. dso__load_kallsyms is the
counterpart of dso__load_vmlinux.

In the process make them also use the symbols rb tree indexed by
map->type, paving the way for supporting other types of symtabs,
such as the next one to be supported: variables.

This also allowed removal of yet another global variable:
kernel_map__functions.

Signed-off-by: Arnaldo 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: <1259346563-12568-7-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:21:59 +01:00
Arnaldo Carvalho de Melo
6a4694a433 perf symbols: Better support for multiple symbol tables per dso
By using an array of rb_roots in struct dso we can, from a
struct map instance to get the right symbol rb_tree more easily.
This way we can have just one symbol lookup method for struct
map instances, map__find_symbol, instead of one per symtab type
(functions, variables).

Signed-off-by: Arnaldo 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: <1259346563-12568-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:21:59 +01:00
Arnaldo Carvalho de Melo
3610583c29 perf symbols: Add a 'type' field to struct map
That way we will be able to check if the right symtab is loaded
in the underlying DSO.

Signed-off-by: Arnaldo 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: <1259346563-12568-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:21:59 +01:00
Arnaldo Carvalho de Melo
605ca4ba01 perf symbols: Unexport kernel_map__functions
perf annotate was the only user, and it doesn't really need it.

Signed-off-by: Arnaldo 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: <1259346563-12568-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:21:58 +01:00
Arnaldo Carvalho de Melo
b0da954a47 perf symbols: Split the dsos list into kernel and user parts
We don't need to look at modules in dsos__findnew because the
kernel events come only with user DSOs. Also we need a way to
list just the module DSOs so that we can create multiple sets of
maps, now that we will support maps for the variables in a
symtab.

Signed-off-by: Arnaldo 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: <1259346563-12568-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:21:58 +01:00
Arnaldo Carvalho de Melo
61f37a824d perf symbols: Rename kernel_mapto kernel_map[s]__functions
As we'll have kernel_map[s]__variables too.

Signed-off-by: Arnaldo 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: <1259346563-12568-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:21:57 +01:00
Arnaldo Carvalho de Melo
3f5ee186f6 perf symbols: Avoid annoying message about loading symbols
This should be properly fixed when we remove the XXX comment in
'perf report', function resolve_symbol.

Signed-off-by: Arnaldo 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: <1259346563-12568-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-27 20:21:57 +01:00
Arnaldo Carvalho de Melo
fcf1203a91 perf symbols: Rename find_symbol routines to find_function
Paving the way for supporting variable in adition to function
symbols.

Signed-off-by: Arnaldo 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: <1259074912-5924-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-24 16:37:03 +01:00
Arnaldo Carvalho de Melo
364794845c perf tools: Introduce zalloc() for the common calloc(1, N) case
This way we type less characters and it looks more like the
kzalloc kernel counterpart.

Signed-off-by: Arnaldo 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: <1259071517-3242-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-24 16:37:02 +01:00
Arnaldo Carvalho de Melo
b32d133aec perf symbols: Simplify symbol machinery setup
And also express its configuration toggles via a struct.

Now all one has to do is to call symbol__init(NULL) if the
defaults are OK, or pass a struct symbol_conf pointer with the
desired configuration.

If a tool uses kernel_maps__find_symbol() to look at the kernel
and modules mappings for a symbol but didn't call symbol__init()
first, that will generate a one time warning too, alerting the
subcommand developer that symbol__init() must be called.

Signed-off-by: Arnaldo 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: <1259071517-3242-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-24 16:37:02 +01:00
Arnaldo Carvalho de Melo
cc612d8199 perf symbols: Look for vmlinux in more places
Now that we can check the buildid to see if it really matches,
this can be done safely:

  vmlinux
  /boot/vmlinux
  /boot/vmlinux-<uts.release>
  /lib/modules/<uts.release>/build/vmlinux
  /usr/lib/debug/lib/modules/%s/vmlinux

More can be added - if you know about distros that put the
vmlinux somewhere else please let us know.

Signed-off-by: Arnaldo 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: <1259001550-8194-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 19:51:48 +01:00
Arnaldo Carvalho de Melo
87f8ea4cd3 perf symbols: Show messages about module loading only if verbose >= 1
Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arnaldo 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: <1258903301-20584-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 18:54:24 +01:00
Pekka Enberg
e57cfcdac6 perf symbols: Fix ELF header errors during "perf kmem record"
The write_event() function in builtin-record.c writes out all
mmap()'d DSOs including non-ELF files like GNOME resource files
and such.

Therefore, check for ELF_K_ELF in filename__read_build_id()
before attempting to read the ELF header with gelf_getehdr().

Fixes the following error messages when running "perf kmem
record":

  penberg@penberg-laptop:~/src/linux/tools/perf$ perf kmem record
  ^C[ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.753 MB perf.data (~32885 samples) ]
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1258885784-11709-1-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 12:19:07 +01:00
Arnaldo Carvalho de Melo
c12e15e71d perf symbols: Old versions of elf.h don't have NT_GNU_BUILD_ID
Signed-off-by: Arnaldo 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: <1258821086-11521-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 17:45:59 +01:00
Arnaldo Carvalho de Melo
90c83218c3 perf symbols: Fixup kernel_maps__fixup_end end map
We better call this routine after both the kernel and modules
are loaded, because as it was if there weren't modules it would not
be called, resulting in kernel_map->end remaining at zero, so no
map would be found and consequently the kernel symtab wouldn't
get loaded, i.e. no kernel symbols would be resolved.

Also this fixes another case, that is when we _have_ modules,
but the last map would have its ->end address not set before we
loaded its symbols, which would never happen because ->end was
not set.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arnaldo 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: <1258821086-11521-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 17:45:58 +01:00
Arnaldo Carvalho de Melo
ef6ae72425 perf symbols: Change the kernel DSO name if it comes from kallsyms
So that the user have a clearer indication about the source of
the symbols, as we only state buildid mismatches in verbose
mode, because 'perf top' would overwrite such warning anyway.

Signed-off-by: Arnaldo 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: <1258757489-5978-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:34 +01:00
Arnaldo Carvalho de Melo
fbd733b815 perf symbols: Check vmlinux buildid
E.g.:

[root@doppio linux-2.6-tip]# perf top -v --vmlinux
../build/tip/vmlinux > /dev/null build_id in vmlinux is
e96699725a47413a50c231864a8e7a8ced40a31b while expected is
18e7cc53db62a7d35e9d6f6c9ddc23017d38ee9a, ignoring it

I.e. perf top was told to use a vmlinux file that is not the one
currently running on the machine, it ignores it and falls back
to using /proc/kallsyms.

This solves many, at first, mysterious results when people have
a stale vmlinux file while keeping the default of trying to use
the vmlinux file in the current directory in things like 'perf
annotate' where the DWARF info is required and thus we can't use
just /proc/kallsyms.

Modules buildids are already being checked as of the previous
changeset in this series, because we are using the default
dso__load routine, that will look at a series of places looking
for the best file with a matching buildid, starting in the
-debuginfo directories.

Signed-off-by: Arnaldo 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: <1258757489-5978-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:34 +01:00
Arnaldo Carvalho de Melo
c338aee853 perf symbols: Do lazy symtab loading for the kernel & modules too
Just like we do with the other DSOs. This also simplifies the
kernel_maps setup process, now all that the tools need to do is
to call kernel_maps__init and the maps for the modules and
kernel will be created, then, later, when
kernel_maps__find_symbol() is used, it will also call
maps__find_symbol that already checks if the symtab was loaded,
loading it if needed.

Now if one does 'perf top --hide_kernel_symbols' we won't pay
the price of loading the (many) symbols in /proc/kallsyms or
vmlinux.

Signed-off-by: Arnaldo 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: <1258757489-5978-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:33 +01:00