Currently perf record always errors out when you run it as non-root with
kptr_restrict == 1, which is often the default.

Make it only warn instead and fix the kernel resolve code to not
segfault later. Profiling works still fine, except kernel symbols are
not resolved.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1411594794-7229-1-git-send-email-andi@firstfloor.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

On systems with more than one socket perf stat --per-core would either
segfault or stop before outputting all cores.

The problem was that the output code referenced the id including the
socket number in the higher bits, which is far beyond any per cpu array.

Mask out the socket number before referencing cpus in abs_printout.

I also renamed the variable in nsec_printout to be clear what it is,
even though it doesn't reference cpus.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Stephane Eranian <eranian@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1411591846-32736-1-git-send-email-andi@firstfloor.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-fdarray-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf tooling updates from Arnaldo Carvalho de Melo.

Infrastructure changes:

  * We were not handling POLLHUP notifications for event file descriptors.

    Fix it by filtering entries in the events file descriptor array after
    poll() returns, refcounting mmaps so that when the last fd pointing to
    a perf mmap goes away we do the unmap. (Arnaldo Carvalho de Melo)

User visible changes:

  * Now 'record' and 'trace' properly exit when a target thread exits.
    (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

So that we don't continue polling on vanished file descriptors, i.e.
file descriptors for events monitoring threads that exited.

I.e. the following 'trace' command now exits as expected, instead
of staying in an eternal loop:

      $ sleep 5s &
      $ trace -p `pidof sleep`
Reported-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-6qegv786zbf6i8us6t4rxug9@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

So that we don't continue polling on vanished file descriptors, i.e.
file descriptors for events monitoring threads that exited.

I.e. the following 'perf record' command now exits as expected, instead
of staying in an eternal loop:

  $ sleep 5s &
  $ perf record -p `pidof sleep`
Reported-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-8dg8o21t2ntzly2bfh53p3sg@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

As noticed by receiving a POLLHUP for all its pollfd entries.

That will remove the refcount taken in perf_evlist__mmap_per_evsel(),
and when all events are consumed via perf_evlist__mmap_read() +
perf_evlist__mmap_consume(), the ring buffer will be unmap'ed.

Thanks to Jiri Olsa for pointing out that we must wait till all events
are consumed, not being ok to unmmap just when receiving all the
POLLHUPs.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-t10w1xk4myp7ca7m9fvip6a0@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We will use this in perf's evlist class so that it can, at
fdarray__filter() time, to unmap the associated ring buffer.

We may need to have further info associated with each fdarray entry, in
that case we'll make that int array a 'union fdarray_priv' one and put a
pointer there so that users can stash whatever they want there. For now,
an int is enough tho.

v2: Add clarification to the per array entry priv area, as well as make
    it a union, which makes usage a bit longer, but if/when we make it
    use more space by allowing per entry pointers existing users source
    code will not have to be changed, just rebuilt.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Link: http://lkml.kernel.org/n/tip-0p00bn83quck3fio3kcs9vca@git.kernel.org

We need to know how many fds are using a perf mmap via
PERF_EVENT_IOC_SET_OUTPUT, so that we can know when to ditch an mmap,
refcount it.

v2: Automatically unmap it when the refcount hits one, which will happen
when all fds are filtered by perf_evlist__filter_pollfd(), in later
patches.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140908153824.GG2773@kernel.org
Link: http://lkml.kernel.org/n/tip-cpv7v2lw0g74ucmxa39xdpms@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The extensible file description array that grew in the perf_evlist class
can be useful for other tools, as it is not something that only evlists
need, so move it to tools/lib/api/fd to ease sharing it.

v2: Don't use {} like in:

 libapi_dirs:
	$(QUIET_MKDIR)mkdir -p $(OUTPUT){fs,fd}/

in Makefiles, as it will not work in some systems, as in ubuntu13.10.

v3: Add fd/*.[ch] to LIBAPIKFS_SOURCES (Fix from Jiri Olsa)

v4: Leave the fcntl(fd, O_NONBLOCK) in the evlist layer, remains to
    be checked if it is really needed there, but has no place in the
    fdarray class (Fix from Jiri Olsa)

v5: Remove evlist details from fdarray grow/filter tests. Improve it a
    bit doing more tests about expected internal state.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-kleuni3hckbc3s0lu6yb9x40@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Since we have access two evlist members in all these poll calls, provide
a helper.

This will also help to make the patch introducing the pollfd class more
clear, as the evlist specific uses will be hiden away
perf_evlist__poll().
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-jr9d4aop4lvy9453qahbcgp0@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Since we can add file descriptors to the evlist pollfd and it will
autogrow, no need to copy all events to a local pollfd array, just add
the timer and stdin file descriptors.
Reviewed-by: David Ahern <dsahern@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-2hvp9iromiheh6rl4oaa08x5@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

  [acme@ssdandy linux]$ perf test "Add fd"
  34: Add fd to pollfd array, making it autogrow             : Ok
  [acme@ssdandy linux]$ perf test -v "Add fd"
  34: Add fd to pollfd array, making it autogrow             :
  --- start ---
  test child forked, pid 19817

  before growing array:   2 [ 1, 2 ]
  after 3rd add_pollfd:   3 [ 1, 2, 35 ]
  after 4th add_pollfd:   4 [ 1, 2, 35, 88 ]
  test child finished with 0
  ---- end ----
  Add fd to pollfd array, making it autogrow: Ok
  [acme@ssdandy linux]$
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-smflpyta146bzog7z0effjss@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This way we will be able to add more file descriptors to be polled,
like stdin or some timer fd.

At this point we might as well yank the pollfd class from evlist so that
it can be used in other places.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-o2mzsjl7taumsoc35ryol00i@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Because we want to notice when they get POLLHUP'ed, so that we can
figure out when all threads exited in a workload being monitored.

We can't just monitor the fds that were mmaped, we need to notice when
all the fds that were PERF_EVENT_IOC_SET_OUTPUT'ed too, because the mmap
stays even after the fd that originally was used to do the mmap call
went away, its only when all the set-output fds for a mmap are gone that
the mmap is.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20140908151016.GH17728@krava.brq.redhat.com
Link: http://lkml.kernel.org/n/tip-24omlq5asrfg4uo3muuzn2bl@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We want to know when the fd went away, like when a monitored thread
exits.

If we do not monitor such events, then the tools will wait forever on
events from a vanished thread, like when running:

 $ sleep 5s &
 $ perf record -p `pidof sleep`

This builds upon the kernel patch by Jiri Olsa that actually makes a
poll on those file descriptors to return POLLHUP.

It is also needed to change the tools to use
perf_evlist__filter_pollfd() to check if there are remainings fds to
monitor or if all are gone, in which case they will exit the
poll/mmap/read loop.
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-a4fslwspov0bs69nj825hqpq@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

That will use a synthetic evlist with just what is touched by this new
method to check that it works as expected.

Output in verbose mode:

  $ perf test -v pollfd
  33: Filter fds with revents mask in a pollfd array         :
  --- start ---
  filtering all but pollfd[2]:
  before:   5 [ 5, 4, 3, 2, 1 ]
   after:   1 [ 3 ]
  filtering all but (pollfd[0], pollfd[3]):
  before:   5 [ 5, 4, 3, 2, 1 ]
   after:   2 [ 5, 2 ]
  test child finished with 0
  ---- end ----
  Filter fds with revents mask in a pollfd array: Ok
  $
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-x7c8liszdvc3ocmanf2cet8p@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To remove all entries in evlist->pollfd[] that have revents matching at
least one of the bits in the specified mask.

It'll adjust evlist->nr_fds to the number of unfiltered fds and will
return this value, as a convenience and to avoid requiring direct access
to internal state of perf_evlist objects.

This will be used after polling the evlist fds so that we remove fds
that were closed by the kernel.
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-y2sca7z3wicvvy40a50lozwm@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This patch restructures the memory controller (IMC) uncore PMU support
for client SNB/IVB/HSW processors. The main change is that it can now
cope with more than one PCI device ID per processor model. There are
many flavors of memory controllers for each processor. They have
different PCI device ID, yet they behave the same w.r.t. the memory
controller PMU that we are interested in.

The patch now supports two distinct memory controllers for IVB
processors: one for mobile, one for desktop.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140917090616.GA11281@quad
Cc: ak@linux.intel.com
Cc: kan.liang@intel.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

The PCU frequency band filters use 8 bit each in a register.
When setting up the value the shift value was not correctly
scaled, which resulted in all filters except for band 0 to
be zero. Fix the scaling.

This allows to correctly monitor multiple uncore frequency bands.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1409872109-31645-5-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

The IvyBridge-EP uncore driver was missing three filter flags:
NC, ISOC, C6 which are useful in some cases. Support them in the same way
as the Haswell EP driver, by allowing to set them and exposing
them in the sysfs formats.

Also fix a typo in a define.

Relies on the Haswell EP driver to be applied earlier.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1409872109-31645-4-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Current code registers PMUs for all possible uncore pci devices.
This is not good because, on some machines, one or more uncore pci
devices can be missing. The missing pci device make corresponding
PMU unusable. Register the PMU only if the uncore device exists.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1409872109-31645-3-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

The uncore subsystem in Haswell-EP is similar to Sandy/Ivy
Bridge-EP. There are some differences in config register
encoding and pci device IDs. The Haswell-EP uncore also
supports a few new events. Add the Haswell-EP driver to
the snbep split driver.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
[ Add missing break. Add imc events. Add cbox nc/isoc/c6. ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1409872109-31645-2-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Use the newly added Broadwell cache event list for Haswell too.
All Haswell and Broadwell events and offcore masks used in these lists
are identical.

However Haswell is very different from the Sandy Bridge
list that was used previously. That fixes a wide range of mis-counting
cache events.

The node events are now only for retired memory events, so prefetching
and speculative memory accesses are not included. They are PEBS
capable now, which makes it much easier to sample for them, plus it's
possible to create address maps with -d.

The prefetch events are gone now. They way the hardware counts
them is very misleading (some prefetches included, others not), so
it seemed best to leave them out.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1409683455-29168-5-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

On Broadwell INST_RETIRED.ALL cannot be used with any period
that doesn't have the lowest 6 bits cleared. And the period
should not be smaller than 128.

Add a new callback to enforce this, and set it for Broadwell.

This is erratum BDM57 and BDM11.

How does this handle the case when an app requests a specific
period with some of the bottom bits set

The apps thinks it is sampling at X occurences per sample, when it is
in fact at X - 63 (worst case).

Short answer:

Any useful instruction sampling period needs to be 4-6 orders
of magnitude larger than 128, as an PMI every 128 instructions
would instantly overwhelm the system and be throttled.
So the +-64 error from this is really small compared to the
period, much smaller than normal system jitter.

Long answer:

<write up by Peter:>

IFF we guarantee perf_event_attr::sample_period >= 128.

Suppose we start out with sample_period=192; then we'll set period_left
to 192, we'll end up with left = 128 (we truncate the lower bits). We
get an interrupt, find that period_left = 64 (>0 so we return 0 and
don't get an overflow handler), up that to 128. Then we trigger again,
at n=256. Then we find period_left = -64 (<=0 so we return 1 and do get
an overflow). We increment with sample_period so we get left = 128. We
fire again, at n=384, period_left = 0 (<=0 so we return 1 and get an
overflow). And on and on.

So while the individual interrupts are 'wrong' we get then with
interval=256,128 in exactly the right ratio to average out at 192. And
this works for everything >=128.

So the num_samples*fixed_period thing is still entirely correct +- 127,
which is good enough I'd say, as you already have that error anyhow.

So no need to 'fix' the tools, al we need to do is refuse to create
INST_RETIRED:ALL events with sample_period < 128.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com>
Cc: Mark Davies <junk@eslaf.co.uk>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1409683455-29168-4-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Add Broadwell support for Broadwell Client to perf.  This is very
similar to Haswell.  It uses a new cache event table, because there
were various changes there.

The constraint list has one new event that needs to be handled over
Haswell.

The PEBS event list is the same, so we reuse Haswell's.

[fengguang.wu: make intel_bdw_event_constraints[] static]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1409683455-29168-3-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Add names for each Haswell model as requested by Peter.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1409683455-29168-2-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

71 is a Broadwell, not a Haswell. The model number was added
by mistake earlier.

Remove it for now, until it can be re-added later with
real Broadwell support.

In practice it does not cause a lot of issues because the Broadwell
PMU is very similar to Haswell, but some details were wrong,
and it's better to handle it correctly.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/1409683455-29168-1-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

This reverts commit 1f9a7268.

With the fix of the initial state for the cloned event we now correctly
handle the error described in:

  1f9a7268 perf: Do not allow optimized switch for non-cloned events

so we can revert it.

I made an automated test for this, but its not suitable for automated
perf tests framework. It needs to be customized for each machine (the
more cpu the higher numbers for GROUPS/WORKERS/BYTES) and it could take
longer time to hit the issue.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140910143535.GD2409@krava.brq.redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Currently we initialize the child event based on the original
parent state. This is wrong, because the original parent event
(and its state) is not related to current fork and also could
be already gone.

We need to initialize the child state based on the immediate
parent event state.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1410520708-19275-2-git-send-email-jolsa@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Currently we return POLLHUP in event polling if the monitored
process is done, but we didn't consider possible children,
that might be still running and producing data.

Before returning POLLHUP making sure that:

   1) the monitored task has exited and that
   2) we don't have any children to monitor

Also adding parent wakeup when the child event is gone.
Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1410520708-19275-1-git-send-email-jolsa@kernel.org
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

User visible changes:

  o Add +field argument support for --sort option (Jiri Olsa)

  o Do not access kallsyms when analyzing user binaries with 'probe' (Masami Hiramatsu)

  o Ignore stripped vmlinux and fallback to kallsyms (Anton Blanchard)

  o Add path to Ubuntu kernel debuginfo file (Anton Blanchard)

  o Disable kernel symbol demangling by default (Avi Kivity)

Infrastructure changes:

  o More intel PT prep work, from Adrian Hunter, including:

    - Let a user specify a PMU event without any config terms
    - Add perf-with-kcore script
    - Let default config be defined for a PMU
    - Add perf_pmu__scan_file()

  o "perf kvm stat report" improvements by Alexander Yarygin:
    o  Save pid string in opts.target.pid
    o  Enable the target.system_wide flag
    o  Unify the title bar output

  o Fix build issue on powerpc when DWARF support is disabled (Anton Blanchard)

  o Allow to specify lib compile variable for spec usage (Jiri Olsa)

  o Fix build on ARM (Stephane Eranian)

  o Fix build on powerpc when DWARF support is disabled (Anton Blanchard)

  o Don't include sys/poll.h directly (Arnaldo Carvalho de Melo)

  o Use ring buffer consume method to look like other tools (Arnaldo Carvalho de Melo)

  o Allow to specify lib compile variable for spec usage (Jiri Olsa)

  o Fix GNU-only grep usage in Makefile (John Spencer)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

All builtins that consume events from perf's ring buffer now end up
calling perf_evlist__mmap_consume(), which will allow unmapping the ring
buffer when all the fds gets closed and all events in the buffer
consumed.

This is in preparation for the patchkit that will notice POLLHUP on
perf events file descriptors.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-8vhaeeoq11ppz0713el4xcps@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Do not use dwfl_module_addrsym if dwarf_diename can find the symbol
name, since dwfl_module_addrsym can be failed on shared libraries.

Without this patch
  ----
  $ perf probe -x ../lib/traceevent/libtraceevent.so -V create_arg_op
  Failed to find symbol at 0x11df1
  Failed to find the address of create_arg_op
    Error: Failed to show vars.
  ----
With this patch
  ----
  $ perf probe -x ../lib/traceevent/libtraceevent.so -V create_arg_op
  Available variables at create_arg_op
          @<create_arg_op+0>
                  enum filter_op_type     btype
                  struct filter_arg*      arg
  ----

This bug was reported on linux-perf-users@vger.kernel.org.
Reported-by: david lerner <dlernerdroid@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: david lerner <dlernerdroid@gmail.com>
Cc: linux-perf-user@vger.kernel.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/1691
Link: http://lkml.kernel.org/r/20140917084101.3722.25299.stgit@kbuild-f20.novalocalSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Do not access kallsyms to show available variables and show source lines
in user binaries.

This behavior always requires the root privilege when sysctl sets
kernel.kptr_restrict=1, but we don't need it just for analyzing user
binaries.

Without this patch (by normal user, kptr_restrict=1):
  ----
  $ perf probe -x ./perf -V add_cmdname
  Failed to init vmlinux path.
    Error: Failed to show vars.
  $ perf probe -x ./perf -L add_cmdname
  Failed to init vmlinux path.
    Error: Failed to show lines.
  ----

With this patch:
  ----
  $ perf probe -x ./perf -V add_cmdname
  Available variables at add_cmdname
          @<perf_unknown_cmd_config+144>
                  (No matched variables)
          @<list_commands_in_dir+160>
                  (No matched variables)
          @<add_cmdname+0>
                  char*   name
                  size_t  len
                  struct cmdnames*        cmds
  $ perf probe -x ./perf -L add_cmdname
  <add_cmdname@/home/fedora/ksrc/linux-3/tools/perf/util/help.c:0>
        0  void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
        1  {
        2         struct cmdname *ent = malloc(sizeof(*ent) + len + 1);

        4         ent->len = len;
        5         memcpy(ent->name, name, len);
        6         ent->name[len] = 0;
  ...
  ----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: david lerner <dlernerdroid@gmail.com>
Cc: linux-perf-user@vger.kernel.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140917084054.3722.73975.stgit@kbuild-f20.novalocal
[ Added missing 'bool user' argument to the !DWARF show_line_range() stub ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Ubuntu places the kernel debuginfo in /usr/lib/debug/boot/vmlinux-*
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
echo Link: http://lkml.kernel.org/n/tip-`ranpwd -l 24`@git.kernel.org
Link: http://lkml.kernel.org/r/20140909091152.2698c0f7@kryten
[ Adapted it to use the perf.data file kernel version as in 0a7e6d1b ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

If a vmlinux is stripped, perf will use it and ignore kallsyms. We
end up with useless profiles where everything maps to a few
runtime symbols:

    63.39%       swapper  [kernel.kallsyms]   [k] hcall_real_table
     4.90%      beam.smp  [kernel.kallsyms]   [k] hcall_real_table
     4.44%      beam.smp  [kernel.kallsyms]   [k] __sched_text_start
     3.72%      beam.smp  [kernel.kallsyms]   [k] __run_at_kexec

Detect this case and fallback to using kallsyms. This fixes the issue:

    62.81%       swapper  [kernel.kallsyms]   [k] snooze_loop
     4.44%      beam.smp  [kernel.kallsyms]   [k] __schedule
     0.91%      beam.smp  [kernel.kallsyms]   [k] _switch
     0.73%      beam.smp  [kernel.kallsyms]   [k] put_prev_entity
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140909085929.4a5a81f0@krytenSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

_BSD_SOURCE was deprecated in favour of _DEFAULT_SOURCE since glibc
2.20[1]. To avoid build warning on glibc2.20, _DEFAULT_SOURCE should
also be defined.

[1]: https://sourceware.org/glibc/wiki/Release/2.20Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1410487817-13403-1-git-send-email-chanho61.park@samsung.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Include poll.h instead.

Fixes the following warning in systems with musl's libc:

  /usr/include/sys/poll.h:1:2: warning: #warning redirecting incorrect #include
  <sys/poll.h> to <poll.h> [-Wcpp]
Reported-by: John Spencer <maillist-linux@barfooze.de>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://thread.gmane.org/gmane.linux.kernel.perf.user/1687/focus=1690
Link: http://lkml.kernel.org/n/tip-k4ocrq1de3fk146oevy346bi@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This makes it work with non-GNU grep's as well.
Signed-off-by: John Spencer <maillist-linux@barfooze.de>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: http://thread.gmane.org/gmane.linux.kernel.perf.user/1686Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Some Linux symbols (for example __vt_event_wait) are interpreted by the
demangler as C++ mangled names, which of course they aren't.

Disable kernel symbol demangling by default to avoid this, and allow
enabling it with a new option --demangle-kernel for those who wish it.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1410581705-26968-1-git-send-email-avi@cloudius-systems.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>