linux-toradex.git/tools/perf/util/header.c, branch v3.2.28

perf tools: Use scnprintf where applicable

2012-03-23T18:21:22+00:00

commit e7f01d1e3d8d501deb8abeaa269d5d48a703b8b0 upstream.

Several places were expecting that the value returned was the number of
characters printed, not what would be printed if there was space.

Fix it by using the scnprintf and vscnprintf variants we inherited from
the kernel sources.

Some corner cases where the number of printed characters were not
accounted were fixed too.

Reported-by: Anton Blanchard 
Cc: Anton Blanchard 
Cc: Eric B Munson 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Yanmin Zhang 
Link: http://lkml.kernel.org/n/tip-kwxo2eh29cxmd8ilixi2005x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Greg Kroah-Hartman

perf header: Use event_name() to get an event name

2011-12-06T11:22:48+00:00

perf_evsel.name may be not initialized

Cc: David Ahern 
Cc: Ingo Molnar 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Arun Sharma 
Cc: devel@openvz.org
Link: http://lkml.kernel.org/r/1322471015-107825-2-git-send-email-avagin@openvz.org
Signed-off-by: Andrew Vagin 
Signed-off-by: Arnaldo Carvalho de Melo

perf header: Fix build on old systems

2011-10-26T15:15:41+00:00

For instance, on Fedora 8:

CC /home/acme/git/build/perf/util/header.o
cc1: warnings being treated as errors
util/header.c: In function ‘write_cpudesc’:
util/header.c:281: warning: implicit declaration of function ‘getline’
util/header.c:281: warning: nested extern declaration of ‘getline’
make: *** [/home/acme/git/build/perf/util/header.o] Error 1
make: Leaving directory `/home/acme/git/linux/tools/perf'
[acme@localhost linux]$

This happens due to header ordering, in perf util.h sets _GNU_SOURCE, so
it must come first.

Reported-by: Ingo Molnar 
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-alfra9wao63euguj7gr8jw7e@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix tracing info recording

2011-10-20T14:41:42+00:00

Fixing the way the tracing information is stored within record command.
The current implementation is causing issues for pipe output.

Following commands fail currently:
	perf script syscall-counts ls
	perf record -e syscalls:sys_exit_read ls | ./perf report -i -

The tracing information is part of the perf data file. It contains
several files from within the tracing debugfs and procs directories.

Beside some static header files, for each tracing event the format
file is added. The /proc/kallsyms file is also added.

The tracing data are stored with preceeding size. This is causing some
dificulties for pipe output, since there's no way to tell debugfs/proc
file size before reading it. So, for pipe output, all the debugfs files
were read twice. Once to get the overall size and once to store the
content itself. This can cause problem in case any of these file
changed, within the storage time.

To fix this behaviour and ensure the integrity of the tracing data, we:
    - read debugfs/proc file into the temp file
    - get temp file size and dump it to the pipe
    - dump the temp file contents to the pipe

Cc: Eric Dumazet 
Cc: Ingo Molnar 
Cc: Neil Horman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/r/20111020135943.GD2092@jolsa.brq.redhat.com
Signed-off-by: Jiri Olsa 
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: handle endianness of feature bitmap

2011-10-19T15:14:35+00:00

Feature bitmap is declared as an array of unsigned longs -- not good
since its size can differ between the host that generated the data file
and the host analyzing the file.

We need to handle endianness, but we don't know the size of the unsigned
long where the file was generated. Take a best guess at determining it:
try 64-bit swap first (ie., file created on a 64-bit host), and check if
the hostname feature bit is set (this feature bit is forced on as of
fbe96f2).  If the bit is not, undo the 64-bit swap and try a 32-bit
swap. If the hostname bit is still not set (e.g., older data file), punt
and fallback to the original behavior -- clearing all feature bits and
setting buildid.

Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1318980841-12616-1-git-send-email-dsahern@gmail.com
Signed-off-by: David Ahern 
Signed-off-by: Arnaldo Carvalho de Melo

perf script: Fix unknown feature comment

2011-10-19T15:12:56+00:00

"perf script -v" emits:

unknown feature 3, continuing...
unknown feature 4, continuing...
unknown feature 5, continuing...
unknown feature 6, continuing...
unknown feature 7, continuing...
unknown feature 8, continuing...
unknown feature 9, continuing...
unknown feature 10, continuing...
unknown feature 11, continuing...
unknown feature 12, continuing...
unknown feature 13, continuing...
unknown feature 14, continuing...

These are all new features added by fbe96f2. Update
perf_file_section__process to know they are valid feature ids.

Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1318984464-20650-1-git-send-email-dsahern@gmail.com
Signed-off-by: David Ahern 
Signed-off-by: Arnaldo Carvalho de Melo

perf buildid: Fix possible unterminated readlink() result buffer

2011-10-14T15:49:35+00:00

The readlink function doesn't guarantee that a '\0' will be put at the
end of the provided buffer if there is no space left.

No need to do "buf[len] = '\0';" since the buffer is allocated with
zalloc().

Link: http://lkml.kernel.org/r/4E986ABF.9040706@intra2net.com
Signed-off-by: Thomas Jarosch 
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Make perf.data more self-descriptive (v8)

2011-10-07T20:01:24+00:00

The goal of this patch is to include more information about the host
environment into the perf.data so it is more self-descriptive. Overtime,
profiles are captured on various machines and it becomes hard to track
what was recorded, on what machine and when.

This patch provides a way to solve this by extending the perf.data file
with basic information about the host machine. To add those extensions,
we leverage the feature bits capabilities of the perf.data format.  The
change is backward compatible with existing perf.data files.

We define the following useful new extensions:
 - HEADER_HOSTNAME: the hostname
 - HEADER_OSRELEASE: the kernel release number
 - HEADER_ARCH: the hw architecture
 - HEADER_CPUDESC: generic CPU description
 - HEADER_NRCPUS: number of online/avail cpus
 - HEADER_CMDLINE: perf command line
 - HEADER_VERSION: perf version
 - HEADER_TOPOLOGY: cpu topology
 - HEADER_EVENT_DESC: full event description (attrs)
 - HEADER_CPUID: easy-to-parse low level CPU identication

The small granularity for the entries is to make it easier to extend
without breaking backward compatiblity. Many entries are provided as
ASCII strings.

Perf report/script have been modified to print the basic information as
easy-to-parse ASCII strings. Extended information about CPU and NUMA
topology may be requested with the -I option.

Thanks to David Ahern for reviewing and testing the many versions of
this patch.

 $ perf report --stdio
 # ========
 # captured on : Mon Sep 26 15:22:14 2011
 # hostname : quad
 # os release : 3.1.0-rc4-tip
 # perf version : 3.1.0-rc4
 # arch : x86_64
 # nrcpus online : 4
 # nrcpus avail : 4
 # cpudesc : Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz
 # cpuid : GenuineIntel,6,15,11
 # total memory : 8105360 kB
 # cmdline : /home/eranian/perfmon/official/tip/build/tools/perf/perf record date
 # event : name = cycles, type = 0, config = 0x0, config1 = 0x0, config2 = 0x0, excl_usr = 0, excl_kern = 0, id = { 29, 30, 31,
 # HEADER_CPU_TOPOLOGY info available, use -I to display
 # HEADER_NUMA_TOPOLOGY info available, use -I to display
 # ========
 #
 ...

 $ perf report --stdio -I
 # ========
 # captured on : Mon Sep 26 15:22:14 2011
 # hostname : quad
 # os release : 3.1.0-rc4-tip
 # perf version : 3.1.0-rc4
 # arch : x86_64
 # nrcpus online : 4
 # nrcpus avail : 4
 # cpudesc : Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz
 # cpuid : GenuineIntel,6,15,11
 # total memory : 8105360 kB
 # cmdline : /home/eranian/perfmon/official/tip/build/tools/perf/perf record date
 # event : name = cycles, type = 0, config = 0x0, config1 = 0x0, config2 = 0x0, excl_usr = 0, excl_kern = 0, id = { 29, 30, 31,
 # sibling cores   : 0-3
 # sibling threads : 0
 # sibling threads : 1
 # sibling threads : 2
 # sibling threads : 3
 # node0 meminfo  : total = 8320608 kB, free = 7571024 kB
 # node0 cpu list : 0-3
 # ========
 #
 ...

Reviewed-by: David Ahern 
Tested-by: David Ahern 
Cc: David Ahern 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Robert Richter 
Cc: Andi Kleen 
Link: http://lkml.kernel.org/r/20110930134040.GA5575@quad
Signed-off-by: Stephane Eranian 
[ committer notes: Use --show-info in the tools as was in the docs, rename
  perf_header_fprintf_info to perf_file_section__fprintf_info, fixup
  conflict with f69b64f7 "perf: Support setting the disassembler style" ]
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 buildid-cache: Zero out buffer of filenames when adding/removing buildid

2011-07-22T11:59:26+00:00

The readlink() function doesn't append a null byte to buf. So we should
zero out buf with zalloc(). Or we'll see sometimes error like this:

[root@intel-s3e36-01]~# /usr/bin/perf buildid-cache -a /lib/modules/2.6.32-130.el6.x86_64/kernel/crypto/twofish_common.ko -v
Adding f64ba8efd5f53c7ad332fc17db1d21de309038e1 /lib/modules/2.6.32-130.el6.x86_64/kernel/crypto/twofish_common.ko: Ok
[root@intel-s3e36-01]~# /usr/bin/perf buildid-cache -r /lib/modules/2.6.32-130.el6.x86_64/kernel/crypto/twofish_common.ko -v
Removing f64ba8efd5f53c7ad332fc17db1d21de309038e1 /lib/modules/2.6.32-130.el6.x86_64/kernel/crypto/twofish_common.ko: FAIL
/lib/modules/2.6.32-130.el6.x86_64/kernel/crypto/twofish_common.ko wasn't in the cache

The change in build_id_cache__add_s() is a defense.

Tested-by: Jiri Olsa 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/20110718031314.GA5802@hpt.nay.redhat.com
Signed-off-by: Han Pingtian 
Signed-off-by: Arnaldo Carvalho de Melo