Commit Graph

12 Commits

Author SHA1 Message Date
Thomas Gleixner 2025cf9e19 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 263 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00
Andi Kleen 61f611593f perf script: Fix LBR skid dump problems in brstackinsn
This is a fix for another instance of the skid problem Milian recently
found [1]

The LBRs don't freeze at the exact same time as the PMI is triggered.
The perf script brstackinsn code that dumps LBR assembler assumes that
the last branch in the LBR leads to the sample point.  But with skid
it's possible that the CPU executes one or more branches before the
sample, but which do not appear in the LBR.

What happens then is either that the sample point is before the last LBR
branch. In this case the dumper sees a negative length and ignores it.
Or it the sample point is long after the last branch. Then the dumper
sees a very long block and dumps it upto its block limit (16k bytes),
which is noise in the output.

On typical sample session this can happen regularly.

This patch tries to detect and handle the situation. On the last block
that is dumped by the LBR dumper we always stop on the first branch. If
the block length is negative just scan forward to the first branch.
Otherwise scan until a branch is found.

The PT decoder already has a function that uses the instruction decoder
to detect branches, so we can just reuse it here.

Then when a terminating branch is found print an indication and stop
dumping. This might miss a few instructions, but at least shows no
runaway blocks.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Link: http://lkml.kernel.org/r/20181120050617.4119-1-andi@firstfloor.org
[ Resolved conflict with dd2e18e9ac ("perf tools: Support 'srccode' output") ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-12-28 16:33:02 -03:00
Ingo Molnar 61f63e3837 perf/core improvements and fixes:
New features:
 
 - Add 'brstackinsn' field in 'perf script' to reuse the x86 instruction
   decoder used in the Intel PT code to study hot paths to samples (Andi Kleen)
 
 Kernel:
 
 - Default UPROBES_EVENTS to Y (Alexei Starovoitov)
 
 - Fix check for kretprobe offset within function entry (Naveen N. Rao)
 
 Infrastructure:
 
 - Introduce util func is_sdt_event() (Ravi Bangoria)
 
 - Make perf_event__synthesize_mmap_events() scale on older kernels where
   reading /proc/pid/maps is way slower than reading /proc/pid/task/pid/maps (Stephane Eranian)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJYyrdSAAoJENZQFvNTUqpAe+4P/3c4ilBSOxLCCxGO7jDYo9oq
 /KqlvsCIg7+vo5eqrOUJAb4qXFnvpYxwjMMkL5rx7gdsBCRfRXIINGWUMrq5mNyk
 MgxuqYnp+yRuxLYml2wn+tdwLzcHWSN2EO9mqQ14N4I+HvgdLmVPQ44ACQXs6KfL
 dk/Ix8YtnFWl2sDZjvyr7ZBqwCPzzklZgHM6erxNUr/WJspzUiixAWqUmewodOUl
 P3PitlHXkITOK3AxSqOjJ4g1k933215nGih7hr0XdjEm4pIYaYksShQ6k9DASCrv
 dn2o1pF1LTu7KCtAo70aaSB7GXydwoA//o2gRbDkSwJJ25DIImZxJXQz9PAYDOo1
 vXSIhmlQ72c4/Yv/XzVOrIoMMMpmWKS3lGZxMVGR/Ie9Gw4kbotkaoEqEpNQsaDZ
 iIaU5v/EcvvToT7T7VHrGg0+vmHgYxm5gSlyASi2IrO2/wJAs0v2pYfuL6gYhXGp
 mhv/pHUv4l9OW+Ubm+zJEEcg337c2RQU5wT/bk4PihxY6nQyEH2Pn5VzdNbZLuMR
 eWnqTH/md+8/bkhmuZJp71wm60oPHoPvbDjvtfVmXAa52AzO+NWSc9Veke3C/QRm
 XgNkrXlzeKopEso3j4gw2iAolqw9t8FHFLGgbTkS+6UCKjAM7vNLiIV02LQqhM50
 qCnKEusMDCRgzeOXxYt+
 =Bg5M
 -----END PGP SIGNATURE-----

Merge tag 'perf-core-for-mingo-4.12-20170316' 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:

New features:

 - Add 'brstackinsn' field in 'perf script' to reuse the x86 instruction
   decoder used in the Intel PT code to study hot paths to samples (Andi Kleen)

Kernel changes:

 - Default UPROBES_EVENTS to Y (Alexei Starovoitov)

 - Fix check for kretprobe offset within function entry (Naveen N. Rao)

Infrastructure changes:

 - Introduce util func is_sdt_event() (Ravi Bangoria)

 - Make perf_event__synthesize_mmap_events() scale on older kernels where
   reading /proc/pid/maps is way slower than reading /proc/pid/task/pid/maps (Stephane Eranian)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-16 17:29:23 +01:00
Andi Kleen 48d02a1d5c perf script: Add 'brstackinsn' for branch stacks
Implement printing instruction sequences as hex dump for branch stacks.

This relies on the x86 instruction decoder used by the PT decoder to
find the lengths of instructions to dump them individually.

This is good enough for pattern matching.

This allows to study hot paths for individual samples, together with
branch misprediction and cycle count / IPC information if available (on
Skylake systems).

  % perf record -b ...
  % perf script -F brstackinsn
  ...
    read_hpet+67:
          ffffffff9905b843        insn: 74 ea                     # PRED
          ffffffff9905b82f        insn: 85 c9
          ffffffff9905b831        insn: 74 12
          ffffffff9905b833        insn: f3 90
          ffffffff9905b835        insn: 48 8b 0f
          ffffffff9905b838        insn: 48 89 ca
          ffffffff9905b83b        insn: 48 c1 ea 20
          ffffffff9905b83f        insn: 39 f2
          ffffffff9905b841        insn: 89 d0
          ffffffff9905b843        insn: 74 ea                     # PRED

Only works when no special branch filters are specified.

Occasionally the path does not reach up to the sample IP, as the LBRs
may be frozen before executing a final jump. In this case we print a
special message.

The instruction dumper piggy backs on the existing infrastructure from
the IP PT decoder.

An earlier iteration of this patch relied on a disassembler, but this
version only uses the existing instruction decoder.

Committer note:

Added hint about how to get suitable perf.data files for use with
'-F brstackinsm':

  $ perf record usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.018 MB perf.data (8 samples) ]
  $
  $ perf script -F brstackinsn
  Display of branch stack assembler requested, but non all-branch filter set
  Hint: run 'perf record -b ...'
  $

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: http://lkml.kernel.org/r/20170223234634.583-1-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-16 09:24:35 -03:00
Ingo Molnar 2b95bd7d58 Merge branch 'linus' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-16 09:50:50 +01:00
Adrian Hunter f1c4d1ad39 perf intel-PT/BTS: Add missing initialization
$ perf test decoder
  57: x86 instruction decoder - new instructions : FAILED!
  $

  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 80 78 56 34 12 	bndstx %bnd0,0x12345678(%rax)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 85 78 56 34 12 	bndstx %bnd0,0x12345678(%rbp)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 84 01 78 56 34 12 	bndstx %bnd0,0x12345678(%rcx,%rax,1)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 84 05 78 56 34 12 	bndstx %bnd0,0x12345678(%rbp,%rax,1)
  Failed to decode 'rel' value (0xfffffffc vs expected 0): 0f 1b 84 08 78 56 34 12 	bndstx %bnd0,0x12345678(%rax,%rcx,1)

There is missing initialization.  It only affects the test because it is
checking 'rel' even in cases where there is no value.

Fix it.

Reported-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/08c6ad07-7994-3e56-b20e-d75727ca7765@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-03 19:07:18 -03:00
Borislav Petkov 940b2f2fd9 x86/events: Remove last remnants of old filenames
Update to the new file paths, remove them from introductory comments.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170218113140.8051-1-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-01 11:27:26 +01:00
Andi Kleen faaa87680b perf intel-pt/bts: Report instruction bytes and length in sample
Change Intel PT and BTS to pass up the length and the instruction
bytes of the decoded or sampled instruction in the perf sample.

The decoder already knows this information, we just need to pass it
up. Since it is only a couple of movs it is not very expensive.

Handle instruction cache too. Make sure ilen is always initialized.

Used in the next patch.

[Adrian: re-base on top (and adjust for) instruction buffer size tidy-up]
[Adrian: add BTS support and adjust commit message accordingly]

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/r/1475847747-30994-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-24 10:31:32 -03:00
Adrian Hunter 32f98aab75 perf intel-pt/bts: Tidy instruction buffer size usage
Tidy instruction buffer size usage in preparation for copying the
instruction bytes onto samples.

The instruction buffer is presently used for debugging, so rename its
size macro from INTEL_PT_INSN_DBG_BUF_SZ to INTEL_PT_INSN_BUF_SZ, and
use it everywhere.

Note that the maximum instruction size is 15 which is a less efficient size
to copy than 16, which is why a separate buffer size is used.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1475847747-30994-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-24 10:31:32 -03:00
Adrian Hunter 97db62062a perf tools: Fix build on powerpc broken by pt/bts
It is theoretically possible to process perf.data files created on x86
and that contain Intel PT or Intel BTS data, on any other architecture,
which is why it is possible for there to be build errors on powerpc
caused by pt/bts.

The errors were:

	util/intel-pt-decoder/intel-pt-insn-decoder.c: In function ‘intel_pt_insn_decoder’:
	util/intel-pt-decoder/intel-pt-insn-decoder.c:138:3: error: switch missing default case [-Werror=switch-default]
	   switch (insn->immediate.nbytes) {
	   ^
	cc1: all warnings being treated as errors

	linux-acme.git/tools/perf/perf-obj/libperf.a(libperf-in.o): In function `intel_pt_synth_branch_sample':
	sources/linux-acme.git/tools/perf/util/intel-pt.c:871: undefined reference to `tsc_to_perf_time'
	linux-acme.git/tools/perf/perf-obj/libperf.a(libperf-in.o): In function `intel_pt_sample':
	sources/linux-acme.git/tools/perf/util/intel-pt.c:915: undefined reference to `tsc_to_perf_time'
	sources/linux-acme.git/tools/perf/util/intel-pt.c:962: undefined reference to `tsc_to_perf_time'
	linux-acme.git/tools/perf/perf-obj/libperf.a(libperf-in.o): In function `intel_pt_process_event':
	sources/linux-acme.git/tools/perf/util/intel-pt.c:1454: undefined reference to `perf_time_to_tsc'

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441046384-28663-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-31 15:47:33 -03:00
Adrian Hunter 5839a5506d perf tools: Fix tarball build broken by pt/bts
Fix some include paths and add missing inat_types.h.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/55D77696.60102@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-22 12:27:07 -03:00
Adrian Hunter 237fae79f5 perf tools: Add Intel PT instruction decoder
Add support for decoding instructions for Intel Processor Trace.  The
kernel x86 instruction decoder is copied for this.

This essentially provides intel_pt_get_insn() which takes a binary
buffer, uses the kernel's x86 instruction decoder to get details of the
instruction and then categorizes it for consumption by an Intel PT
decoder.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1439450095-30122-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-17 11:11:36 -03:00