This patch adds support for taken branch sampling, i.e, the
PERF_SAMPLE_BRANCH_STACK feature to perf report. In other
words, to display histograms based on taken branches rather
than executed instructions addresses.
The new option is called -b and it takes no argument. To
generate meaningful output, the perf.data must have been
obtained using perf record -b xxx ... where xxx is a branch
filter option.
The output shows symbols, modules, sorted by 'who branches
where' the most often. The percentages reported in the first
column refer to the total number of branches captured and
not the usual number of samples.
Here is a quick example.
Here branchy is simple test program which looks as follows:
void f2(void)
{}
void f3(void)
{}
void f1(unsigned long n)
{
if (n & 1UL)
f2();
else
f3();
}
int main(void)
{
unsigned long i;
for (i=0; i < N; i++)
f1(i);
return 0;
}
Here is the output captured on Nehalem, if we are
only interested in user level function calls.
$ perf record -b any_call,u -e cycles:u branchy
$ perf report -b --sort=symbol
52.34% [.] main [.] f1
24.04% [.] f1 [.] f3
23.60% [.] f1 [.] f2
0.01% [k] _IO_new_file_xsputn [k] _IO_file_overflow
0.01% [k] _IO_vfprintf_internal [k] _IO_new_file_xsputn
0.01% [k] _IO_vfprintf_internal [k] strchrnul
0.01% [k] __printf [k] _IO_vfprintf_internal
0.01% [k] main [k] __printf
About half (52%) of the call branches captured are from main()
-> f1(). The second half (24%+23%) is split in two equal shares
between f1() -> f2(), f1() ->f3(). The output is as expected
given the code.
It should be noted, that using -b in perf record does not
eliminate information in the perf.data file. Consequently, a
typical profile can also be obtained by perf report by simply
not using its -b option.
It is possible to sort on branch related columns:
- dso_from, symbol_from
- dso_to, symbol_to
- mispredict
Signed-off-by: Roberto Agostino Vitillo <ravitillo@lbl.gov>
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: acme@redhat.com
Cc: robert.richter@amd.com
Cc: ming.m.lin@intel.com
Cc: andi@firstfloor.org
Cc: asharma@fb.com
Cc: vweaver1@eecs.utk.edu
Cc: khandual@linux.vnet.ibm.com
Cc: dsahern@gmail.com
Link: http://lkml.kernel.org/r/1328826068-11713-14-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Pull perf fixes from Ingo Molnar:
"It contains three cherry-picked fixes from perf/core, which turned out
to be more urgent than we originally thought."
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf tools: Handle kernels that don't support attr.exclude_{guest,host}
perf tools: Change perf_guest default back to false
perf record: No build id option fails
If perf_evsel__open() failed, the errno was set and returned properly.
However since the perf_evlist__open() called close() on fd's for all of
evsel x cpu x thread after the failure, the errno was overridden by
other code (EBADF). So the caller of the function ended up seeing
different error message and getting confused.
Fit it by restoring original return value. Because one of caller of the
function is in the python extension, and it uses system errno
internally, it'd be better restoring the original value rather than
using the return value of the function directly, IMHO (i.e. I'm not a
python expert :)
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1329966816-23175-1-git-send-email-namhyung.kim@lge.com
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch allows cpupower tool to generate its output files in a
seperate directory. This is now possible by passing the 'O=<path>' to
the command line.
This can be usefull for a normal user if the kernel source code is
located in a read only location.
This is patch stole some bits of the perf makefile.
[linux@dominikbrodowski.net: fix commit message]
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Use the '-p' and '-o' switches to specify the pathname of the output
file to xgettext(1). This avoids to move manually the output file if
xgettext(1) succeeds.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
UTIL_BINS and IDLE_OBJS variables are not defined at all, so
there's no need to remove their content from the 'clean' target.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Looks like some not needed debug code slipped in.
Also this code:
tmp = sysfs_get_idlestate_name(cpu, idlestates - 1);
performs a strdup and the mem was not freed again.
-> delete it.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
The number of idle states was wrong.
The POLL idle state (on X86) was missed out:
Number of idle states: 4
Available idle states: C1-NHM C3-NHM C6-NHM
While the POLL is not a real idle state, its
statistics should still be shown. It's now also
explained in a detailed manpage.
This should fix a bug of missing the first idle
state on other archs.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
cpupower-frequency-* manpages slightly differed from the others.
- Use uppercase letters in the title
- Show cpupower Manual in the header
- Remove Mattia from left down corner of the manpage, he is already
listed as author
- Remove --help, prints this message -> not needed
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
The last missing manpage for cpupower tools.
More info about other architecture's sleep state specialities would be great.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
AMD's BKDG (Bios and Kernel Developers Guide) talks in the CPU spec of their
CPU families about PCI registers defined by "device" (slot) and func(tion).
Assuming that CPU specific configuration PCI devices are always on domain
and bus zero a pci_slot_func_init() func which gets the slot and func of
the desired PCI device passed looks like the most convenient way.
This also obsoletes the PCI device id maintenance.
Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: Andreas Herrmann <herrmann.der.user@googlemail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Pulling latest branches from Ingo:
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
memblock: Fix size aligning of memblock_alloc_base_nid()
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf probe: Ensure offset provided is not greater than function length without DWARF info too
perf tools: Ensure comm string is properly terminated
perf probe: Ensure offset provided is not greater than function length
perf evlist: Return first evsel for non-sample event on old kernel
perf/hwbp: Fix a possible memory leak
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
CPU hotplug, cpusets, suspend: Don't touch cpusets during suspend/resume
USB: Gadget: changes for 3.4
This merge is rather big. Here's what it contains:
For am5536udc we have just simple coding style fixes. Nothing that has any
potential to cause any issues going forward.
With mv_udc, there's only one single change removing an unneeded NULL check.
at91_udc also only saw a single change this merge window, and that's only
removing a duplicated header.
The Renesas controller has a few more involved changes. Support for SUDMAC was
added, there's now a special handling of IRQ resources for when the IRQ line is
shared between Renesas controller and SUDMAC, we also had a bug fix where
Renesas controller would sleep in atomic context while doing DMA transfers from
a tasklet. There were also a set of minor cleanups.
The FSL UDC also had a scheduling in atomic context bug fix, but that's all.
Thanks to Sebastian, the dummy_hcd now works better than ever with support for
scatterlists and streams. Sebastian also added SuperSpeed descriptors to the
serial gadgets.
The highlight on this merge is the addition of a generic API for mapping and
unmapping usb_requests. This will avoid code duplication on all UDC controllers
and also kills all the defines for DMA_ADDR_INVALID which UDC controllers
sprinkled around. A few of the UDC controllers were already converted to use
this new API.
Conflicts:
drivers/usb/dwc3/gadget.c
If threads in a multi-threaded process have names shorter than the main
thread the comm for the named threads is not properly terminated.
E.g., for the process 'namedthreads' where each thread is named noploop%d
where %d is the thread number:
Before:
perf script -f comm,tid,ip,sym,dso
noploop:4ads 21616 400a49 noploop (/tmp/namedthreads)
The 'ads' in the thread comm bleeds over from the process name.
After:
perf script -f comm,tid,ip,sym,dso
noploop:4 21616 400a49 noploop (/tmp/namedthreads)
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1330111898-68071-1-git-send-email-dsahern@gmail.com
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are various hostprogs in the kernel that are rolling their own
implementations of {get,put}_unaligned_le*(). Copy the byteshift
headers from include/linux/unaligned so that they can all use a single
implementation.
This requires changing some of the data types to the userspace
exported ones (u32 -> __u32, etc).
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-2-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
While demoing ktest at ELC in 2012, it was embarrassing that the
make_min_config test failed to work because the snowball board I was
testing it against had a config that would not build. But the
make_min_config only tested the testing part and ignored build failures.
The end result was a config file that would not boot.
This time, for real.
* tag 'ktest-fix-make-min-failed-build-for-real' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest:
ktest: Fix make_min_config test when build fails
The make_min_config does not take into account when the build fails,
resulting in a invalid MIN_CONFIG .config file. When the build fails,
it is ignored and the boot test is executed, using the previous built
kernel. The configs that should be tested are not tested and they may
be added or removed depending on the result of the last kernel that
succeeded to be built.
If the build fails, mark the current config as a failure and the
configs that were disabled may still be needed.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The following commit:
b52956c perf tools: Allow multiple threads or processes in record, stat, top
introduced a bug in the thread_map code which caused perf record -a to
not setup system-wide monitoring properly.
$ taskset -c 1 noploop 1000 &
$ perf record -a -C 1 sleep 10
$ perf report -D | tail -20
cycles stats:
TOTAL events: 4413
MMAP events: 4025
COMM events: 340
SAMPLE events: 48
Here I was expecting about 10,000 samples and not 48.
In system-wide mode, the PID passed to perf_event_open() must be -1 and
it was 0. That caused the kernel to setup a per-process event on PID:0.
Consequently, the number of samples captured does not correspond to the
requested measurement.
The following one-liner fixes the problem for me with or without -C.
I would also suggest to change the malloc() to something that matches
the struct definition. thread_map->map[] is declared as int map[] and
not pid_t map[]. If map[] can only contain pids, then change the struct
definition.
Acked-by: David Ahern <dsahern@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120221145424.GA6757@quad
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
