When in the hists browser, i.e. in 'perf report' or in 'perf top', it is
possible to press '/' and specify a substring to filter by symbol name.

Clarify how to remove a filter by making the prompt be:

   Please enter the name of symbol you want to see.
   To remove the filter later, press / + ENTER

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-vbq2b0kyufwy6p0ctkfswcoe@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

They were repurposed for horizontal scrolling, so use just ENTER/ESC in
the help messages.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: c6c3c02d ("perf hists browser: Implement horizontal scrolling")
Link: http://lkml.kernel.org/n/tip-n5ar4qg8fs12ax4vhr3rxhxj@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Not as the first attempt at finding a vmlinux for the running kernel,
this way we get a more informative filename to present in tools, it will
check that the build-id is the same as the one previously loaded in the
DSO in dso->build_id, reading from /sys/kernel/notes, for instance.

E.g. in the annotation TUI, going from 'perf top', for the scsi_sg_alloc
kernel function, in the first line:

Before:

scsi_sg_alloc  /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1

After:

scsi_sg_alloc  /lib/modules/4.3.0-rc1+/build/vmlinux

And:

  # ls -la /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1
lrwxrwxrwx. 1 root root 81 Sep 22 16:11 /root/.debug/.build-id/28/2777c262e6b3c0451375163c9a81c893218ab1 -> ../../home/git/build/v4.3.0-rc1+/vmlinux/282777c262e6b3c0451375163c9a81c893218ab1
  # file ~/.debug/home/git/build/v4.3.0-rc1+/vmlinux/282777c262e6b3c0451375163c9a81c893218ab1
/root/.debug/home/git/build/v4.3.0-rc1+/vmlinux/282777c262e6b3c0451375163c9a81c893218ab1: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, BuildID[sha1]=282777c262e6b3c0451375163c9a81c893218ab1, not stripped
  #

The same as:

  # file /lib/modules/4.3.0-rc1+/build/vmlinux
/lib/modules/4.3.0-rc1+/build/vmlinux: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, BuildID[sha1]=282777c262e6b3c0451375163c9a81c893218ab1, not stripped

Furthermore:

  # sha256sum /lib/modules/4.3.0-rc1+/build/vmlinux
  e7a789bbdc61029ec09140c228e1dd651271f38ef0b8416c0b7d5ff727b98be2  /lib/modules/4.3.0-rc1+/build/vmlinux
  # sha256sum ~/.debug/home/git/build/v4.3.0-rc1+/vmlinux/282777c262e6b3c0451375163c9a81c893218ab1
  e7a789bbdc61029ec09140c228e1dd651271f38ef0b8416c0b7d5ff727b98be2  /root/.debug/home/git/build/v4.3.0-rc1+/vmlinux/282777c262e6b3c0451375163c9a81c893218ab1
  [root@zoo new]#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9y42ikzq3jisiddoi6f07n8z@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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:

  - Adding a field via 'perf report -F' that already is enabled makes
    the tool get stuck in a loop, fix it. (Jiri Olsa)

Infrastructure changes:

  - Support PERF_RECORD_SWITCH in the python binding. (Arnaldo Carvalho de Melo)

  - Fix handling read() result using a signed variable, found with Coccinelle.
    (Andrzej Hajda)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

To test it check tools/perf/python/twatch.py, after following the
instructions there to enable context_switch, output looks like:

  [root@zoo linux]# tools/perf/python/twatch.py
  cpu: 1, pid: 31463, tid: 31463 { type: context_switch, next_prev_pid: 31463, next_prev_tid: 31463, switch_out: 0 }
  cpu: 2, pid: 31463, tid: 31496 { type: context_switch, next_prev_pid: 31463, next_prev_tid: 31496, switch_out: 0 }
  cpu: 2, pid: 31463, tid: 31496 { type: context_switch, next_prev_pid: 31463, next_prev_tid: 31496, switch_out: 1 }
  cpu: 3, pid: 31463, tid: 31527 { type: context_switch, next_prev_pid: 31463, next_prev_tid: 31527, switch_out: 0 }
  cpu: 1, pid: 31463, tid: 31463 { type: context_switch, next_prev_pid: 31463, next_prev_tid: 31463, switch_out: 1 }
  cpu: 3, pid: 31463, tid: 31527 { type: context_switch, next_prev_pid: 31463, next_prev_tid: 31527, switch_out: 1 }
  cpu: 1, pid: 31463, tid: 31463 { type: context_switch, next_prev_pid: 31463, next_prev_tid: 31463, switch_out: 0 }
  ^CTraceback (most recent call last):
    File "tools/perf/python/twatch.py", line 67, in <module>
      main(context_switch = 1, thread = 31463)
    File "tools/perf/python/twatch.py", line 40, in main
      evlist.poll(timeout = -1)
  KeyboardInterrupt
  [root@zoo linux]#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Guy Streeter <streeter@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-1ukistmpamc5z717k80ctcp2@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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

Pull perf/urgent fix from Arnaldo Carvalho de Melo:

  - Fix build break on (at least) powerpc due to sample_reg_masks, not being
    available for linking. (Sukadev Bhattiprolu)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

perf_regs.c does not get built on Powerpc as CONFIG_PERF_REGS is false.
So the weak definition for 'sample_regs_masks' doesn't get picked up.

Adding perf_regs.o to util/Build unconditionally, exposes a redefinition
error for 'perf_reg_value()' function (due to the static inline version
in util/perf_regs.h). So use #ifdef HAVE_PERF_REGS_SUPPORT' around that
function.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: linuxppc-dev@ozlabs.org
Link: http://lkml.kernel.org/r/20150930182836.GA27858@us.ibm.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Bugfixes:
   - Fix a use-after-free bug in the RPC/RDMA client
   - Fix a write performance regression
   - Fix up page writeback accounting
   - Don't try to reclaim unused state owners
   - Fix a NFSv4 nograce recovery hang
   - reset states to use open_stateid when returning delegation
     voluntarily
   - Fix a tracepoint NULL-pointer dereference"

* tag 'nfs-for-4.3-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: Fix a tracepoint NULL-pointer dereference
  nfs4: reset states to use open_stateid when returning delegation voluntarily
  NFSv4: Fix a nograce recovery hang
  NFSv4.1: nfs4_opendata_check_deleg needs to handle NFS4_OPEN_CLAIM_DELEG_CUR_FH
  NFSv4: Don't try to reclaim unused state owners
  NFS: Fix a write performance regression
  NFS: Fix up page writeback accounting
  xprtrdma: disconnect and flush cqs before freeing buffers

This reverts commit 998ef75d.

The commit itself does not appear to be buggy per se, but it is exposing
a bug in ext4 (and Ted thinks ext3 too, but we solved that by getting
rid of it).  It's too late in the release cycle to really worry about
this, even if Dave Hansen has a patch that may actually fix the
underlying ext4 problem.  We can (and should) revisit this for the next
release.

The problem is that moving the prefaulting later now exposes a special
case with partially successful writes that isn't handled correctly.  And
the prefaulting likely isn't normally even that much of a performance
issue - it looks like at least one reason Dave saw this in his
performance tests is that he also ran them on Skylake that now supports
the new SMAP code, which makes the normally very cheap user space
prefaulting noticeably more expensive.
Bisected-and-acked-by: Ted Ts'o <tytso@mit.edu>
Analyzed-and-acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Running xfstest generic/013 with the tracepoint nfs:nfs4_open_file
enabled produces a NULL-pointer dereference when calculating fileid and
filehandle of the opened file.  Fix this by checking if state is NULL
before trying to use the inode pointer.
Reported-by: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

The function can return negative value, assigning it to unsigned
variable can cause memory corruption.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/1444122017-16856-1-git-send-email-a.hajda@samsung.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf_hpp__init currently does not respect sorting dimensions and the
setup_sorting function could endup queueing same format twice. That
screwed up the perf_hpp__list and got stuck in loop within
perf_hpp__setup_output_field function.

  $ perf report -F +overhead

  0x00000000004c1355 in perf_hpp__is_sort_entry (format=format@entry=0x880440 <perf_hpp.format>) at util/sort.c:1506
  1506    {

     #0  0x00000000004c1355 in perf_hpp__is_sort_entry (format=format@entry=0x880440 <perf_hpp.format>) at util/sort.c:1506
     #1  0x00000000004c139d in perf_hpp__same_sort_entry (a=a@entry=0x880440 <perf_hpp.format>, b=b@entry=0x2bb2fe0) at util/sort.c:1380
     #2  0x00000000004f8d3c in perf_hpp__setup_output_field () at ui/hist.c:554
     #3  0x00000000004c1d1e in setup_sorting () at util/sort.c:1984
     #4  0x000000000042efbf in cmd_report (argc=0, argv=0x7ffea5a0e790, prefix=<optimized out>) at builtin-report.c:874
     #5  0x0000000000476f13 in run_builtin (p=p@entry=0x875628 <commands+168>, argc=argc@entry=3, argv=argv@entry=0x7ffea5a0e790) at perf.c:385
     #6  0x000000000047710b in handle_internal_command (argc=3, argv=0x7ffea5a0e790) at perf.c:445
     #7  0x0000000000477176 in run_argv (argcp=argcp@entry=0x7ffea5a0e5fc, argv=argv@entry=0x7ffea5a0e5f0) at perf.c:489
     #8  0x00000000004773e7 in main (argc=3, argv=0x7ffea5a0e790) at perf.c:606

Using hpp_dimension__add_output function to register the output column.
It will also mark the dimension as taken and omit above stuck.
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444134312-29136-4-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This function will allow to register output column from ui code and
respect taken sort/output dimensions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444134312-29136-3-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

There's no need to call reset_dimensions within __setup_output_field
function. It's already called in its caller setup_sorting right before
perf_hpp__init, which will be changed in following patch to respect
taken dimension.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444134312-29136-2-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

In multi-segment system, uncore devices may belong to buses whose segment
number is other than 0:

  ....
  0000:ff:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03)
  ...
  0001:7f:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03)
  ...
  0001:bf:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03)
  ...
  0001:ff:10.5 System peripheral: Intel Corporation Xeon E5 v3/Core i7 Scratchpad & Semaphore Registers (rev 03
  ...

In that case, relation of bus number and physical id may be broken
because "uncore_pcibus_to_physid" doesn't take account of PCI segment.
For example, bus 0000:ff and 0001:ff uses the same entry of
"uncore_pcibus_to_physid" array.

This patch fixes this problem by introducing the segment-aware pci2phy_map instead.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: hpa@zytor.com
Link: http://lkml.kernel.org/r/1443096621-4119-1-git-send-email-izumi.taku@jp.fujitsu.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

This patch adds new PMUs to support cstate related free running
(read-only) counters. These counters may be used simultaneously by other
tools, such as turbostat. However, it still make sense to implement them
in perf. Because we can conveniently collect them together with other
events, and allow to use them from tools without special MSR access
code.

These counters include CORE_C*_RESIDENCY and PKG_C*_RESIDENCY.
According to counters' scope and category, two PMUs are registered with
the perf_event core subsystem.

 - 'cstate_core': The counter is available for each physical core. The
                  counters include CORE_C*_RESIDENCY.

 - 'cstate_pkg':  The counter is available for each physical package. The
                  counters include PKG_C*_RESIDENCY.

The events are exposed in sysfs for use by perf stat and other tools.
The files are:

  /sys/devices/cstate_core/events/c*-residency
  /sys/devices/cstate_pkg/events/c*-residency

These events only support system-wide mode counting.
The /sys/devices/cstate_*/cpumask file can be used by tools to figure
out which CPUs to monitor by default.

The PMU type (attr->type) is dynamically allocated and is available from
/sys/devices/core_misc/type and /sys/device/cstate_*/type.

Sampling is not supported.

Here is an example.

 - To caculate the fraction of time when the core is running in C6 state
   CORE_C6_time% = CORE_C6_RESIDENCY / TSC

 # perf stat -x, -e"cstate_core/c6-residency/,msr/tsc/" -C0 -- taskset -c 0 sleep 5

   11838820015,,cstate_core/c6-residency/,5175919658,100.00
   11877130740,,msr/tsc/,5175922010,100.00

 For sleep, 99.7% of time we ran in C6 state.

 # perf stat -x, -e"cstate_core/c6-residency/,msr/tsc/" -C0 -- taskset -c 0 busyloop

   1253316,,cstate_core/c6-residency/,4360969154,100.00
   10012635248,,msr/tsc/,4360972366,100.00

 For busyloop, 0.01% of time we ran in C6 state.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1443443404-8581-1-git-send-email-kan.liang@intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull xen bug fixes from David Vrabel:

 - Fix VM save performance regression with x86 PV guests

 - Make kexec work in x86 PVHVM guests (if Xen has the soft-reset ABI)

 - Other minor fixes.

* tag 'for-linus-4.3b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen/p2m: hint at the last populated P2M entry
  x86/xen: Do not clip xen_e820_map to xen_e820_map_entries when sanitizing map
  x86/xen: Support kexec/kdump in HVM guests by doing a soft reset
  xen/x86: Don't try to write syscall-related MSRs for PV guests
  xen: use correct type for HYPERVISOR_memory_op()

Pull s390 fixes from Martin Schwidefsky:
 "Three bug fixes and an update to the default configuration"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/defconfig: set SCSI_DH=y
  s390/vtime: correct scaled cputime of partially idle CPUs
  s390/boot/decompression: disable floating point in decompressor
  s390/numa: use correct type for node_to_cpumask_map

Pull CIFS fixes from Steve French:
 "Two fixes for problems pointed out by automated tools.

  Thanks PaX/grsecurity team and Dan Carpenter (and the Smatch tool)"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  [CIFS] Update cifs version number
  [SMB3] Do not fall back to SMBWriteX in set_file_size error cases
  [SMB3] Missing null tcon check

With commit 633d6f17 (x86/xen: prepare
p2m list for memory hotplug) the P2M may be sized to accomdate a much
larger amount of memory than the domain currently has.

When saving a domain, the toolstack must scan all the P2M looking for
populated pages.  This results in a performance regression due to the
unnecessary scanning.

Instead of reporting (via shared_info) the maximum possible size of
the P2M, hint at the last PFN which might be populated.  This hint is
increased as new leaves are added to the P2M (in the expectation that
they will be used for populated entries).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org> # 4.0+

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:

  - Switch the default callchain output mode to 'graph,0.5,caller', to make it
    look like the default for other tools, reducing the learning curve for
    people used to 'caller' based viewing. (Arnaldo Carvalho de Melo)

  - Implement column based horizontal scrolling in the hists browser (top, report),
    making it possible to use the TUI for things like 'perf mem report' where
    there are many more columns than can fit in a terminal. (Arnaldo Carvalho de Melo)

  - Support sorting by symbol_iaddr with perf.data files produced by
    'perf mem record'. (Don Zickus)

  - Display DATA_SRC sample type bit, i.e. when running 'perf evlist -v' the
    "DATA_SRC" wasn't appearing when set, fix it to look like: (Jiri Olsa)

      cpu/mem-loads/pp: ...SNIP... sample_type: IP|TID|TIME|ADDR|CPU|PERIOD|DATA_SRC

  - Introduce the 'P' event modifier, meaning 'max precision level, please', i.e.:

     $ perf record -e cycles:P usleep 1

    Is now similar to:

     $ perf record usleep 1

    Useful, for instance, when specifying multiple events. (Jiri Olsa)

  - Make 'perf -v' and 'perf -h' work. (Jiri Olsa)

  - Fail properly when pattern matching fails to find a tracepoint, i.e.
    '-e non:existent' was being correctly handled, with a proper error message
    about that not being a valid event, but '-e non:existent*' wasn't,
    fix it. (Jiri Olsa)

Infrastructure changes:

  - Separate arch specific entries in 'perf test' and add an 'Intel CQM' one
    to be fun on x86 only. (Matt Fleming)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Currently we dont fail properly when pattern matching fails to find any
tracepoint.

Current behaviour:

  $ perf record -e 'sched:krava*' sleep 1
  WARNING: event parser found nothinginvalid or unsupported event: 'sched:krava*'
  Run 'perf list' for a list of valid events

  usage: perf record [<options>] [<command>]
     or: perf record [<options>] -- <command> [<options>]

This patch change:

  $ perf record -e 'sched:krava*' sleep 1
  event syntax error: 'sched:krava*'
                       \___ unknown tracepoint

  Error:  File /sys/kernel/debug/tracing/events/sched/krava* not found.
  Hint:   Perhaps this kernel misses some CONFIG_ setting to enable this feature?.

  Run 'perf list' for a list of valid events

   usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]
Reported-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444073477-3181-1-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Do it using the recently introduced ui_brower scrolling mode, setting
ui_browser.columns to the number of sort columns and then, when
rendering each line, skipping as many initial columns as the user
pressed the right arrow.

As the user presses the left arrow, the ui_browser code will remove the
scrolling counter and the left scrolling takes place.

The right arrow key was an alias for ENTER, so people used to press it
may get a bit annoyed at first, sorry! Ditto for ESC and the left key.

Callchains can be left as is or we can, when rendering the Symbol
column, store the at what position on the screen it is and then
using ui_browser__gotorc() to print it from there, i.e. the callchain
would move around with the symbol.

Leaving it as is, i.e. at a fixed position, close to the left, saves
precious screen real state for it, so I'm inclined to leave it as is
now.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-ccqq9sabgfge5dwbqjwh71ij@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

If the classes derived from ui_browser want to do some sort of
horizontal scrolling, they have just to set ui_browser->columns to
the number of columns available.

Those columns can be the number of characters on the screen, if what is
desired is to scroll character by character, or the number of columns in
a spreadsheet like table.

This is what the hist_browser will do, skipping ui_browser->horiz_scroll
columns when rendering each of its lines.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-q6a22bpmpgcr1awgzrmd4jrs@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Which is the most common default found in other similar tools.
Requested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://www.youtube.com/watch?v=nXaxk27zwlk
Link: http://lkml.kernel.org/n/tip-v8lq36aispvdwgxdmt9p9jd9@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Peter reports that it's possible to trigger a WARN_ON_ONCE() in the
Intel CQM code by combining a hardware event and an Intel CQM
(software) event into a group. Unfortunately, the perf tools are not
able to create this bundle and we need to manually construct a test
case.

For posterity, record Peter's proof of concept test case in tools/perf
so that it presents a model for how we can perform architecture
specific tests, or "arch tests", in perf in the future.

The particular issue triggered in the test case is that when the
counter for the hardware event overflows and triggers a PMI we'll read
both the hardware event and the software event counters.
Unfortunately, for CQM that involves performing an IPI to read the CQM
event counters on all sockets, which in NMI context triggers the
WARN_ON_ONCE().
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Vikas Shivappa <vikas.shivappa@intel.com>
Cc: Vince Weaver <vince@deater.net>
Link: http://lkml.kernel.org/r/1437490509-15373-1-git-send-email-matt@codeblueprint.co.uk
Link: http://lkml.kernel.org/n/tip-3p4ra0u8vzm7m289a1m799kf@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Move out the x86-specific tests into tools/perf/arch/x86/tests and
define an 'arch_tests' array, which is the list of tests that only apply
to the build architecture.

We can also now begin to get rid of some of the #ifdef code that is
present in the generic perf tests.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@intel.com>
Cc: Vince Weaver <vince@deater.net>
Link: http://lkml.kernel.org/n/tip-9s68h4ptg06ah0lgnjz55mqn@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Tests that only make sense for some architectures currently live in
the same place as the generic tests. Move out the x86-specific tests
into tools/perf/arch/x86/tests and define an 'arch_tests' array, which
is the list of tests that only apply to the build architecture.

The main idea is to encourage developers to add arch tests to build
out perf's test coverage, without dumping everything in
tools/perf/tests.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vikas Shivappa <vikas.shivappa@intel.com>
Cc: Vince Weaver <vince@deater.net>
Link: http://lkml.kernel.org/n/tip-p4uc1c15ssbj8xj7ku5slpa6@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Adding handling for '-h' and '-v' options to invoke help and version
command respectively.

Current behaviour is:

   $ perf -v
   Unknown option: -v

    Usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS]
   $ perf -h
   Unknown option: -h

    Usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS]

New behaviour:

  $ perf -h

   usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS]

   The most commonly used perf commands are:
     annotate        Read perf.data (created by perf record) and display annotated code
     archive         Create archive with object files with build-ids found in perf.data file
     bench           General framework for benchmark suites
   ...

  $ perf -v
  perf version 4.3.rc3.gc99e32

Updated man page.
Requested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-10-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We need to properly initialize column width for symbol_iaddr field, so
all symbols could fit in the column.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-9-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Sorting on 'symbol' gives to broad a resolution as it can cover a range
of IP address.  Use the iaddr instead to get proper sorting on IP
addresses.  Need to use the 'mem_sort' feature of perf record.

New sort option is: symbol_iaddr, header label is 'Code Symbol'.

  $ perf mem report --stdio -F +symbol_iaddr
  # Overhead       Samples  Code Symbol              Local Weight
  # ........  ............  ........................ ............
  #
      54.08%             1  [k] nmi_handle           192
       4.51%             1  [k] finish_task_switch   16
       3.66%             1  [.] malloc               13
       3.10%             1  [.] __strcoll_l          11
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-8-git-send-email-jolsa@kernel.orgSigned-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We cant test 'P' modifier gets properly parsed, the functionality test
itself is beyond this suite.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-7-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The 'P' will cause the event to get maximum possible detected precise
level.

Following record:
  $ perf record -e cycles:P ...

will detect maximum precise level for 'cycles' event and use it.

Commiter note:

Testing it:

  $ perf record -e cycles:P usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.013 MB perf.data (9 samples) ]
  $ perf evlist
  cycles:P
  $ perf evlist -v
  cycles:P: size: 112, { sample_period, sample_freq }: 4000, sample_type:
  IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1,
  enable_on_exec: 1, task: 1, precise_ip: 2, sample_id_all: 1, mmap2: 1,
  comm_exec: 1
  $
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-6-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It'll be used in following patch.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-5-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The annotated_source::sizeof_sym_hist could easily overflow int size,
resulting in crash in __symbol__inc_addr_samples.

Changing its type int size_t as was probably intended from beginning
based on the initialization code in symbol__alloc_hist.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-4-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Adding DATA_SRC bit_name call to display sample_type properly.

   $ perf evlist -v
   cpu/mem-loads/pp: ...SNIP... sample_type: IP|TID|TIME|ADDR|CPU|PERIOD|DATA_SRC, ...
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-3-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Because there's no point, PATH_MAX is big enough.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-2-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull strscpy string copy function implementation from Chris Metcalf.

Chris sent this during the merge window, but I waffled back and forth on
the pull request, which is why it's going in only now.

The new "strscpy()" function is definitely easier to use and more secure
than either strncpy() or strlcpy(), both of which are horrible nasty
interfaces that have serious and irredeemable problems.

strncpy() has a useless return value, and doesn't NUL-terminate an
overlong result.  To make matters worse, it pads a short result with
zeroes, which is a performance disaster if you have big buffers.

strlcpy(), by contrast, is a mis-designed "fix" for strlcpy(), lacking
the insane NUL padding, but having a differently broken return value
which returns the original length of the source string.  Which means
that it will read characters past the count from the source buffer, and
you have to trust the source to be properly terminated.  It also makes
error handling fragile, since the test for overflow is unnecessarily
subtle.

strscpy() avoids both these problems, guaranteeing the NUL termination
(but not excessive padding) if the destination size wasn't zero, and
making the overflow condition very obvious by returning -E2BIG.  It also
doesn't read past the size of the source, and can thus be used for
untrusted source data too.

So why did I waffle about this for so long?

Every time we introduce a new-and-improved interface, people start doing
these interminable series of trivial conversion patches.

And every time that happens, somebody does some silly mistake, and the
conversion patch to the improved interface actually makes things worse.
Because the patch is mindnumbing and trivial, nobody has the attention
span to look at it carefully, and it's usually done over large swatches
of source code which means that not every conversion gets tested.

So I'm pulling the strscpy() support because it *is* a better interface.
But I will refuse to pull mindless conversion patches.  Use this in
places where it makes sense, but don't do trivial patches to fix things
that aren't actually known to be broken.

* 'strscpy' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: use global strscpy() rather than private copy
  string: provide strscpy()
  Make asm/word-at-a-time.h available on all architectures