linux.git/tools/perf/arch, branch v4.8-rc2

perf probe ppc64le: Fix probe location when using DWARF

2016-08-09T15:14:29+00:00

Powerpc has Global Entry Point and Local Entry Point for functions.  LEP
catches call from both the GEP and the LEP. Symbol table of ELF contains
GEP and Offset from which we can calculate LEP, but debuginfo does not
have LEP info.

Currently, perf prioritize symbol table over dwarf to probe on LEP for
ppc64le. But when user tries to probe with function parameter, we fall
back to using dwarf(i.e. GEP) and when function called via LEP, probe
will never hit.

For example:

  $ objdump -d vmlinux
    ...
    do_sys_open():
    c0000000002eb4a0:       e8 00 4c 3c     addis   r2,r12,232
    c0000000002eb4a4:       60 00 42 38     addi    r2,r2,96
    c0000000002eb4a8:       a6 02 08 7c     mflr    r0
    c0000000002eb4ac:       d0 ff 41 fb     std     r26,-48(r1)

  $ sudo ./perf probe do_sys_open
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060904

  $ sudo ./perf probe 'do_sys_open filename:string'
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060896 filename_string=+0(%gpr4):string

For second case, perf probed on GEP. So when function will be called via
LEP, probe won't hit.

  $ sudo ./perf record -a -e probe:do_sys_open ls
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.195 MB perf.data ]

To resolve this issue, let's not prioritize symbol table, let perf
decide what it wants to use. Perf is already converting GEP to LEP when
it uses symbol table. When perf uses debuginfo, let it find LEP offset
form symbol table. This way we fall back to probe on LEP for all cases.

After patch:

  $ sudo ./perf probe 'do_sys_open filename:string'
  $ sudo cat /sys/kernel/debug/tracing/kprobe_events
    p:probe/do_sys_open _text+3060904 filename_string=+0(%gpr4):string

  $ sudo ./perf record -a -e probe:do_sys_open ls
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.197 MB perf.data (11 samples) ]

Signed-off-by: Ravi Bangoria 
Acked-by: Masami Hiramatsu 
Cc: Alexander Shishkin 
Cc: Ananth N Mavinakayanahalli 
Cc: Balbir Singh 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1470723805-5081-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-07-30T19:11:36+00:00

Pull perf fixes from Thomas Gleixner:
 "This update contains:

   - a fix for the bpf tools to use the new EM_BPF code

   - a fix for the module parser of perf to retrieve the
     proper text start address

   - add str_error_c to libapi to avoid linking against
     tools/lib/str_error_r.o"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools lib api: Add str_error_c to libapi
  perf s390: Fix 'start' address of module's map
  tools lib bpf: Use official ELF e_machine value

Merge tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2016-07-29T00:38:16+00:00

Pull libnvdimm updates from Dan Williams:

 - Replace pcommit with ADR / directed-flushing.

   The pcommit instruction, which has not shipped on any product, is
   deprecated.  Instead, the requirement is that platforms implement
   either ADR, or provide one or more flush addresses per nvdimm.

   ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers
   to the memory controller on a power-fail event.

   Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware
   Interface Table (NFIT) sub-structure: "Flush Hint Address Structure".
   A flush hint is an mmio address that when written and fenced assures
   that all previous posted writes targeting a given dimm have been
   flushed to media.

 - On-demand ARS (address range scrub).

   Linux uses the results of the ACPI ARS commands to track bad blocks
   in pmem devices.  When latent errors are detected we re-scrub the
   media to refresh the bad block list, userspace can also request a
   re-scrub at any time.

 - Support for the Microsoft DSM (device specific method) command
   format.

 - Support for EDK2/OVMF virtual disk device memory ranges.

 - Various fixes and cleanups across the subsystem.

* tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits)
  libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
  nfit: do an ARS scrub on hitting a latent media error
  nfit: move to nfit/ sub-directory
  nfit, libnvdimm: allow an ARS scrub to be triggered on demand
  libnvdimm: register nvdimm_bus devices with an nd_bus driver
  pmem: clarify a debug print in pmem_clear_poison
  x86/insn: remove pcommit
  Revert "KVM: x86: add pcommit support"
  nfit, tools/testing/nvdimm/: unify shutdown paths
  libnvdimm: move ->module to struct nvdimm_bus_descriptor
  nfit: cleanup acpi_nfit_init calling convention
  nfit: fix _FIT evaluation memory leak + use after free
  tools/testing/nvdimm: add manufacturing_{date|location} dimm properties
  tools/testing/nvdimm: add virtual ramdisk range
  acpi, nfit: treat virtual ramdisk SPA as pmem region
  pmem: kill __pmem address space
  pmem: kill wmb_pmem()
  libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes
  fs/dax: remove wmb_pmem()
  libnvdimm, pmem: flush posted-write queues on shutdown
  ...

perf s390: Fix 'start' address of module's map

2016-07-26T19:46:12+00:00

At present, when creating module's map, perf gets 'start' address by
parsing '/proc/modules', but it's the module base address, it isn't the
start address of the '.text' section.

In most arches, it's OK. But for s390, it places 'GOT' and 'PLT'
relocations before '.text' section. So there exists an offset between
module base address and '.text' section, which will incur wrong symbol
resolution for modules.

Fix this bug by getting 'start' address of module's map from parsing
'/sys/module/[module name]/sections/.text', not from '/proc/modules'.

Signed-off-by: Song Shan Gong 
Acked-by: Jiri Olsa 
Cc: Christian Borntraeger 
Cc: David Ahern 
Link: http://lkml.kernel.org/r/1469070651-6447-2-git-send-email-gongss@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo

x86/insn: remove pcommit

2016-07-23T18:04:23+00:00

The pcommit instruction is being deprecated in favor of either ADR
(asynchronous DRAM refresh: flush-on-power-fail) at the platform level, or
posted-write-queue flush addresses as defined by the ACPI 6.x NFIT (NVDIMM
Firmware Interface Table).

Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: x86@kernel.org
Cc: Josh Poimboeuf 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Borislav Petkov 
Cc: Andy Lutomirski 
Cc: Xiao Guangrong 
Cc: Adrian Hunter 
Cc: Ross Zwisler 
Acked-by: Ingo Molnar 
Signed-off-by: Dan Williams

perf tools: Add AVX-512 instructions to the new instructions test

2016-07-21T12:37:26+00:00

Previous patches added support for Intel's AVX-512 instructions to the
kernel and perf tools instruction decoders.

AVX-512 instructions are documented in Intel Architecture Instruction
Set Extensions Programming Reference (February 2016).

Add a representative set of instructions to perf's "new instructions"
test. e.g.

	perf test "new instructions"

Or to view a particular instruction:

	perf test -v "new instructions" 2>&1 | grep vbroadcasti64x4

Signed-off-by: Adrian Hunter 
Acked-by: Ingo Molnar 
Acked-by: Masami Hiramatsu 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Andy Lutomirski 
Cc: Dan Williams 
Cc: H. Peter Anvin 
Cc: Jiri Olsa 
Cc: Thomas Gleixner 
Cc: X86 ML 
Link: http://lkml.kernel.org/r/1469003437-32706-5-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

x86/insn: perf tools: Fix vcvtph2ps instruction decoding

2016-07-20T12:57:46+00:00

vcvtph2ps does not have an immediate operand, so remove the erroneous
'Ib' from its opcode map entry. Add vcvtph2ps to the perf tools new
instructions test to verify it.

Signed-off-by: Adrian Hunter 
Acked-by: Ingo Molnar 
Acked-by: Masami Hiramatsu 
Cc: Andy Lutomirski 
Cc: Dan Williams 
Cc: H. Peter Anvin 
Cc: Jiri Olsa 
Cc: Thomas Gleixner 
Cc: X86 ML 
Link: http://lkml.kernel.org/r/1469003437-32706-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove needless includes from cache.h

2016-07-12T18:19:58+00:00

The cache.h header doesn't use any of the definitions in some of the
headers it includes, ditch them and fix the fallout, where files were
getting stuff they needed just because they were including it, sometimes
not using what it really exports at all.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-l6r2bmj8h1g3e01wr981on0n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tests x86 rdpmc: Add missing headers

2016-07-12T18:19:57+00:00

Another case of a file using definitions and getting them by chance,
from indirect header inclusion, fix it.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-o3l1vi4gw2w6xyc6z4ig938s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools: Introduce str_error_r()

2016-07-12T18:19:47+00:00

The tools so far have been using the strerror_r() GNU variant, that
returns a string, be it the buffer passed or something else.

But that, besides being tricky in cases where we expect that the
function using strerror_r() returns the error formatted in a provided
buffer (we have to check if it returned something else and copy that
instead), breaks the build on systems not using glibc, like Alpine
Linux, where musl libc is used.

So, introduce yet another wrapper, str_error_r(), that has the GNU
interface, but uses the portable XSI variant of strerror_r(), so that
users rest asured that the provided buffer is used and it is what is
returned.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-d4t42fnf48ytlk8rjxs822tf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo