linux-toradex.git/tools/perf/util/symbol.h, branch v3.2.15

perf report: Add option to show total period

2011-10-07T15:12:13+00:00

Just like --show-nr-samples, to help in diagnosing problems in the
tools.

Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-1lr7ejdjfvy2uwy2wkmatcpq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Make output more readable

2011-08-18T10:38:21+00:00

This patch adds two new options to perf annotate:
	- --no-asm-raw : Do not display raw instruction encodings
	- --no-source  : Do not interleave source code with assembly code

We believe those options make the output of annotate more readable.

Systematically displaying source can make it hard to follow code and
especially optimized code.

Raw encodings are not useful in most cases.

Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20110517153207.GA9834@quad
Signed-off-by: Stephane Eranian 
[committer note: Use the 'no-' option inverting logic]
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Use properly build_id kernel binaries

2011-08-11T11:58:03+00:00

If we bring the recorded perf data together with kernel binary from another
machine using:

	on server A:
	perf archive

	on server B:
	tar xjvf perf.data.tar.bz2 -C ~/.debug

the build_id kernel dso is not properly recognized during the "perf report"
command on server B.

The reason is, that build_id dsos are added during the session initialization,
while the kernel maps are created during the sample event processing.

The machine__create_kernel_maps functions ends up creating new dso object for
kernel, but it does not check if we already have one added by build_id
processing.

Also the build_id reading ABI quirk added in commit:

 - commit b25114817a73bbd2b84ce9dba02ee1ef8989a947
   perf build-id: Add quirk to deal with perf.data file format breakage

populates the "struct build_id_event::pid" with 0, which
is later interpreted as DEFAULT_GUEST_KERNEL_ID.

This is not always correct, so it's better to guess the pid
value based on the "struct build_id_event::header::misc" value.

- Tested with data generated on x86 kernel version v2.6.34
  and reported back on x86_64 current kernel.
- Not tested for guest kernel case.

Note the problem stays for PERF_RECORD_MMAP events recorded by perf that
does not use proper pid (HOST_KERNEL_ID/DEFAULT_GUEST_KERNEL_ID). They are
misinterpreted within the current perf code. Probably there's not much we
can do about that.

Cc: Avi Kivity 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Yanmin Zhang 
Link: http://lkml.kernel.org/r/20110601194346.GB1934@jolsa.brq.redhat.com
Signed-off-by: Jiri Olsa 
Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Handle /proc/sys/kernel/kptr_restrict

2011-05-26T14:15:25+00:00

Perf uses /proc/modules to figure out where kernel modules are loaded.

With the advent of kptr_restrict, non root users get zeroes for all module
start addresses.

So check if kptr_restrict is non zero and don't generate the syntethic
PERF_RECORD_MMAP events for them.

Warn the user about it in perf record and in perf report.

In perf report the reference relocation symbol being zero means that
kptr_restrict was set, thus /proc/kallsyms has only zeroed addresses, so don't
use it to fixup symbol addresses when using a valid kallsyms (in the buildid
cache) or vmlinux (in the vmlinux path) build-id located automatically or
specified by the user.

Provide an explanation about it in 'perf report' if kernel samples were taken,
checking if a suitable vmlinux or kallsyms was found/specified.

Restricted /proc/kallsyms don't go to the buildid cache anymore.

Example:

 [acme@emilia ~]$ perf record -F 100000 sleep 1

 WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted, check
 /proc/sys/kernel/kptr_restrict.

 Samples in kernel functions may not be resolved if a suitable vmlinux file is
 not found in the buildid cache or in the vmlinux path.

 Samples in kernel modules won't be resolved at all.

 If some relocation was applied (e.g. kexec) symbols may be misresolved even
 with a suitable vmlinux or kallsyms file.

 [ perf record: Woken up 1 times to write data ]
 [ perf record: Captured and wrote 0.005 MB perf.data (~231 samples) ]
 [acme@emilia ~]$

 [acme@emilia ~]$ perf report --stdio
 Kernel address maps (/proc/{kallsyms,modules}) were restricted,
 check /proc/sys/kernel/kptr_restrict before running 'perf record'.

 If some relocation was applied (e.g. kexec) symbols may be misresolved.

 Samples in kernel modules can't be resolved as well.

 # Events: 13  cycles
 #
 # Overhead  Command      Shared Object                 Symbol
 # ........  .......  .................  .....................
 #
    20.24%    sleep  [kernel.kallsyms]  [k] page_fault
    20.04%    sleep  [kernel.kallsyms]  [k] filemap_fault
    19.78%    sleep  [kernel.kallsyms]  [k] __lru_cache_add
    19.69%    sleep  ld-2.12.so         [.] memcpy
    14.71%    sleep  [kernel.kallsyms]  [k] dput
     4.70%    sleep  [kernel.kallsyms]  [k] flush_signal_handlers
     0.73%    sleep  [kernel.kallsyms]  [k] perf_event_comm
     0.11%    sleep  [kernel.kallsyms]  [k] native_write_msr_safe

 #
 # (For a higher level overview, try: perf report --sort comm,dso)
 #
 [acme@emilia ~]$

This is because it found a suitable vmlinux (build-id checked) in
/lib/modules/2.6.39-rc7+/build/vmlinux (use -v in perf report to see the long
file name).

If we remove that file from the vmlinux path:

 [root@emilia ~]# mv /lib/modules/2.6.39-rc7+/build/vmlinux \
		     /lib/modules/2.6.39-rc7+/build/vmlinux.OFF
 [acme@emilia ~]$ perf report --stdio
 [kernel.kallsyms] with build id 57298cdbe0131f6871667ec0eaab4804dcf6f562
 not found, continuing without symbols

 Kernel address maps (/proc/{kallsyms,modules}) were restricted, check
 /proc/sys/kernel/kptr_restrict before running 'perf record'.

 As no suitable kallsyms nor vmlinux was found, kernel samples can't be
 resolved.

 Samples in kernel modules can't be resolved as well.

 # Events: 13  cycles
 #
 # Overhead  Command      Shared Object  Symbol
 # ........  .......  .................  ......
 #
    80.31%    sleep  [kernel.kallsyms]  [k] 0xffffffff8103425a
    19.69%    sleep  ld-2.12.so         [.] memcpy

 #
 # (For a higher level overview, try: perf report --sort comm,dso)
 #
 [acme@emilia ~]$

Reported-by: Stephane Eranian 
Suggested-by: David Miller 
Cc: Dave Jones 
Cc: David Miller 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Kees Cook 
Cc: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Pekka Enberg 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Tom Zanussi 
Link: http://lkml.kernel.org/n/tip-mt512joaxxbhhp1odop04yit@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Give more useful names to 'self' parameters

2011-04-19T11:18:35+00:00

One more installment on an area that is mostly dormant.

Suggested-by: Thomas Gleixner 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Cc: Tom Zanussi 
LKML-Reference: 
Signed-off-by: Arnaldo Carvalho de Melo

perf symbol: Move sym_entry->skip to symbol->ignore

2011-03-11T16:36:01+00:00

While going thru each of the sym_entry fields looking to reduce it to
the set of entries needed when in an active symbols list, 'skip' should
really be in symbol, as we set it when loading the symtab.

And the space used by the basic symbol allocation remains the same as
we had 5 bytes of padding.

Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Tom Zanussi 
LKML-Reference: 
Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Rename dso->origin to dso->symtab_type

2011-03-11T16:28:45+00:00

And the DSO__ORIG_ enum to SYMTAB__, to clarify that this is about from
where the symtab was obtained.

Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Tom Zanussi 
LKML-Reference: 
Signed-off-by: Arnaldo Carvalho de Melo

perf hists: Remove needless global col lenght calcs

2011-03-06T01:31:04+00:00

To support multiple events we need to do these calcs per 'struct hists'
instance, and it turns out we already do that at:

	__hists__add_entry
		hists__inc_nr_entries
			hists__calc_col_len

for all the unfiltered hist_entry instances we stash in the rb tree, so
trow away the dead code.

Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Tom Zanussi 
LKML-Reference: 
Signed-off-by: Arnaldo Carvalho de Melo

Merge commit 'v2.6.37-rc8' into perf/core

2011-01-04T07:08:54+00:00

Merge reason: pick up latest -rc.

Signed-off-by: Ingo Molnar

perf symbols: Improve kallsyms symbol end addr calculation

2010-12-22T22:31:45+00:00

For kallsyms we don't have the symbol address end, so we do an extra pass and
set the symbol end addr as being the start of the next minus one.

But this was being done just after we filtered the symbols of a
particular type (functions, variables), so the symbol end was sometimes
after what it really is.

Fixing up symbol end also was falling apart when we have symbol aliases,
then the end address of all but the last alias was being set to be
before its start.

Fix it up by checking for symbol aliases and making the kallsyms__parse
routine use the next symbol, whatever its type, as the limit for the
previous symbol, passing that end address to the callback.

This was detected by the 'perf test' synthetic paranoid regression
tests, fix it up so that even that case doesn't mislead us.

Cc: Frederic Weisbecker 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Paul Mackerras 
Cc: Stephane Eranian 
LKML-Reference: 
Signed-off-by: Arnaldo Carvalho de Melo