Commit Graph

29 Commits

Author SHA1 Message Date
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that 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 you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Jin Yao a36ebe4e24 perf config: Rename to HAVE_DWARF_GETLOCATIONS_SUPPORT
In Makefile.config, to make all libraries flags have _SUPPORT suffix,
rename HAVE_DWARF_GETLOCATIONS to HAVE_DWARF_GETLOCATIONS_SUPPORT

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Suggested-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1522402036-22915-4-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-02 13:50:24 -03:00
Arnaldo Carvalho de Melo a43783aeec perf tools: Include errno.h where needed
Removing it from util.h, part of an effort to disentangle the includes
hell, that makes changes to util.h or something included by it to cause
a complete rebuild of the tools.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ztrjy52q1rqcchuy3rubfgt2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19 13:01:51 -03:00
Arnaldo Carvalho de Melo a067558e2f perf tools: Move extra string util functions to util/string2.h
Moving them from util.h, where they don't belong. Since libc already
have string.h, name it slightly differently, as string2.h.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-eh3vz5sqxsrdd8lodoro4jrw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19 13:01:51 -03:00
Arnaldo Carvalho de Melo fd20e8111c perf tools: Including missing inttypes.h header
Needed to use the PRI[xu](32,64) formatting macros.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-wkbho8kaw24q67dd11q0j39f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-19 13:01:46 -03:00
Masami Hiramatsu d5a00296a6 perf probe: Match linkage name with mangled name
Match linkage name with mangled name if exists. The linkage_name is used
for storing mangled name of the object.

Thus, this allows 'perf probe' to find appropriate probe point from
mangled symbol as below.

E.g. without this fix:
  ----
  $ perf probe -x /usr/lib64/libstdc++.so.6 \
    -D _ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
  Probe point '_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv'
  not found.
    Error: Failed to add events.
  ----

With this fix, perf probe can find the correct one.
  ----
  $ perf probe -x /usr/lib64/libstdc++.so.6 \
    -D _ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
  p:probe_libstdc/_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
  /usr/lib64/libstdc++.so.6.0.22:0x8ca60
  ----

Committer notes:

After the fix, setting it for real (no -D/--definition, that amounts to
a --dry-run):

  # perf probe -x /usr/lib64/libstdc++.so.6 _ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
  Added new event:
    probe_libstdc:_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv (on _ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv in /usr/lib64/libstdc++.so.6.0.22)

  You can now use it in all perf tools, such as:

	perf record -e probe_libstdc:_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv -aR sleep 1

  # perf probe -l probe_libstdc:*
    probe_libstdc:_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv (on is_open@libstdc++-v3/include/fstream in /usr/lib64/libstdc++.so.6.0.22)
  #

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147464493162.29804.16715053505069382443.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-29 11:17:08 -03:00
Ravi Bangoria 6243b9dc4c perf probe: Move dwarf specific functions to dwarf-aux.c
Move generic dwarf related functions from util/probe-finder.c to
util/dwarf-aux.c. Functions name and their prototype are also changed
accordingly. No functionality changes.

Suggested-and-Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1472546377-25612-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-01 12:42:26 -03:00
Masami Hiramatsu bf4d5f25c9 perf probe: Check the return value of strbuf APIs
Check the return value of strbuf APIs in perf-probe
related code, so that it can handle errors in strbuf.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160510054707.6158.69861.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-10 11:53:34 -03:00
Arnaldo Carvalho de Melo bd0419e2a5 perf probe: Check if dwarf_getlocations() is available
If not, tell the user that:

  config/Makefile:273: Old libdw.h, finding variables at given 'perf probe' point will not work, install elfutils-devel/libdw-dev >= 0.157

And return -ENOTSUPP in die_get_var_range(), failing features that
need it, like the one pointed out above.

This fixes the build on older systems, such as Ubuntu 12.04.5.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Vinson Lee <vlee@freedesktop.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9l7luqkq4gfnx7vrklkq4obs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-06 10:44:28 -03:00
Arnaldo Carvalho de Melo 88fd633cdf perf probe: No need to use formatting strbuf method
We have addch() for chars, add() for fixed size data, and addstr() for
variable length strings, use them.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0ap02fn2xtvpduj2j6b2o1j4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-03-23 16:53:05 -03:00
Masami Hiramatsu 86a7602745 perf probe: Fix to add missed brace around if block
The commit 75186a9b09 (perf probe: Fix to show lines of sys_ functions
correctly) introduced a bug by a missed brace around if block. This
fixes to add it.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 75186a9b09 ("perf probe: Fix to show lines of sys_ functions correctly")
Link: http://lkml.kernel.org/r/20150812215541.9088.62425.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-13 14:51:26 -03:00
Masami Hiramatsu 75186a9b09 perf probe: Fix to show lines of sys_ functions correctly
"perf probe --lines sys_poll" shows only the first line of sys_poll,
because the SYSCALL_DEFINE macro:

  ----
  SYSCALL_DEFINE*(foo,...)
  {
    body;
  }
  ----

  is expanded as below (on debuginfo)

  ----

  static inline int SYSC_foo(...)
  {
    body;
  }
  int SyS_foo(...) <- is an alias of sys_foo.
  {
    return SYSC_foo(...);
  }
  ----

So, "perf probe --lines sys_foo" decodes SyS_foo function and it also skips
inlined functions(SYSC_foo) inside the target function because those functions
are usually defined somewhere else.

To fix this issue, this fix checks whether the inlined function is defined at
the same point of the target function, and if so, it doesn't skip the inline
function.

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20150812012406.11811.94691.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-12 13:20:27 -03:00
Jiri Olsa c1b9034db7 perf tools: Fix dwarf-aux.c compilation on i386
Replacing %lu format strings for Dwarf_Addr type with PRIu64 as it fits
for Dwarf_Addr (defined as uint64_t) type and works also on both 32/64
bits.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
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/1431706991-15646-1-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-15 16:59:43 -03:00
Naveen N. Rao d4c537e6bf perf probe: Ignore tail calls to probed functions
perf probe currently errors out if there are any tail calls to probed
functions:

[root@rhel71be]# perf probe do_fork
Failed to find probe point in any functions.
  Error: Failed to add events.

Fix this by teaching perf to ignore tail calls.

Without patch:

  [root@rhel71be perf]# ./perf probe -v do_fork
  probe-definition(0): do_fork symbol:do_fork file:(null) line:0 offset:0
  return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (7 entries long)
  symsrc__init: build id mismatch for /boot/vmlinux.
  Using /usr/lib/debug/lib/modules/3.10.0-201.el7.ppc64/vmlinux for symbols
  Open Debuginfo file:
  /usr/lib/debug/lib/modules/3.10.0-201.el7.ppc64/vmlinux
  Try to find probe point from debuginfo.
  found inline addr: 0xc0000000000bb9b0
  Probe point found: do_fork+0
  found inline addr: 0xc0000000000bbe20
  Probe point found: kernel_thread+48
  found inline addr: 0xc0000000000bbe5c
  Probe point found: sys_fork+28
  found inline addr: 0xc0000000000bbfac
  Probe point found: sys_vfork+44
  found inline addr: 0xc0000000000bc27c
  Failed to find probe point in any functions.
  An error occurred in debuginfo analysis (-2).
  Error: Failed to add events. Reason: No such file or directory (Code: -2)

With patch:

  [root@rhel71be perf]# ./perf probe -v do_fork
  probe-definition(0): do_fork symbol:do_fork file:(null) line:0 offset:0
  return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (7 entries long)
  symsrc__init: build id mismatch for /boot/vmlinux.
  Using /usr/lib/debug/lib/modules/3.10.0-201.el7.ppc64/vmlinux for symbols
  Open Debuginfo file:
  /usr/lib/debug/lib/modules/3.10.0-201.el7.ppc64/vmlinux
  Try to find probe point from debuginfo.
  found inline addr: 0xc0000000000bb9b0
  Probe point found: do_fork+0
  found inline addr: 0xc0000000000bbe20
  Probe point found: kernel_thread+48
  found inline addr: 0xc0000000000bbe5c
  Probe point found: sys_fork+28
  found inline addr: 0xc0000000000bbfac
  Probe point found: sys_vfork+44
  found inline addr: 0xc0000000000bc27c
  Ignoring tail call from SyS_clone
  Found 4 probe_trace_events.
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  No kprobe blacklist support, ignored
  Added new events:
  Writing event: p:probe/do_fork _text+768432
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)

[Ignore the error about failure to write event - this kernel is missing
a patch to resolve _text properly]

The reason to ignore tail calls is that the address does not belong to
any function frame. In the example above, the address in SyS_clone is
0xc0000000000bc27c, but looking at the debug-info:

 <1><830081>: Abbrev Number: 133 (DW_TAG_subprogram)
    <830083>   DW_AT_external    : 1
    <830083>   DW_AT_name        : (indirect string, offset: 0x3cea3): SyS_clone
    <830087>   DW_AT_decl_file   : 7
    <830088>   DW_AT_decl_line   : 1689
    <83008a>   DW_AT_prototyped  : 1
    <83008a>   DW_AT_type        : <0x8110eb>
    <83008e>   DW_AT_low_pc      : 0xc0000000000bc270
    <830096>   DW_AT_high_pc     : 0xc
    <83009e>   DW_AT_frame_base  : 1 byte block: 9c 	(DW_OP_call_frame_cfa)
    <8300a0>   DW_AT_GNU_all_call_sites: 1
    <8300a0>   DW_AT_sibling     : <0x830178>
<snip>
 <3><830147>: Abbrev Number: 125 (DW_TAG_GNU_call_site)
    <830148>   DW_AT_low_pc      : 0xc0000000000bc27c
    <830150>   DW_AT_GNU_tail_call: 1
    <830150>   DW_AT_abstract_origin: <0x82e7e1>

The frame ends at 0xc0000000000bc27c. I suppose this is why this
particular call is a "tail" call. FWIW, systemtap seems to ignore these
as well and requires users to explicitly place probes at these call
sites if necessary. I print out the caller so that users know.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/1430394151-15928-1-git-send-email-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-14 10:05:09 -03:00
He Kuang 349e8d2611 perf probe: Add --range option to show a variable's location range
It is not easy for users to get the accurate byte offset or the line
number where a local variable can be probed.

With '--range' option, local variables in the scope of the probe point
are showed with a byte offset range, and can be added according to this
range information.

For example, there are some variables in the function
generic_perform_write():

  <generic_perform_write@mm/filemap.c:0>
  0  ssize_t generic_perform_write(struct file *file,
  1                                 struct iov_iter *i, loff_t pos)
  2  {
  3          struct address_space *mapping = file->f_mapping;
  4          const struct address_space_operations *a_ops = mapping->a_ops;
  ...
  42                 status = a_ops->write_begin(file, mapping, pos, bytes, flags,
                                               &page, &fsdata);
  44                 if (unlikely(status < 0))

But we fail when we try to probe the variable 'a_ops' at line 42 or 44.

  $ perf probe --add 'generic_perform_write:42 a_ops'
  Failed to find the location of a_ops at this address.
    Perhaps, it has been optimized out.

This is because the source code do not match the assembly, so a variable
may not be available in the source code line where it appears.

After this patch, we can lookup the accurate byte offset range of a
variable, 'INV' indicates that this variable is not valid at the given
point, but available in the scope:

  $ perf probe --vars 'generic_perform_write:42' --range
  Available variables at generic_perform_write:42
    @<generic_perform_write+141>
       [INV] ssize_t written @<generic_perform_write+[324-331]>
       [INV] struct address_space_operations*        a_ops   @<generic_perform_write+[55-61,170-176,223-246]>
       [VAL] (unknown_type)  fsdata  @<generic_perform_write+[70-307,346-411]>
       [VAL] loff_t  pos     @<generic_perform_write+[0-286,286-336,346-411]>
       [VAL] long int        status  @<generic_perform_write+[83-342,346-411]>
       [VAL] long unsigned int       bytes   @<generic_perform_write+[122-311,320-338,346-403,403-411]>
       [VAL] struct address_space*   mapping @<generic_perform_write+[35-344,346-411]>
       [VAL] struct iov_iter*        i       @<generic_perform_write+[0-340,346-411]>
       [VAL] struct page*    page    @<generic_perform_write+[70-307,346-411]>

Then it is more clear for us to add a probe with this variable:

  $ perf probe --add 'generic_perform_write+170 a_ops'
  Added new event:
    probe:generic_perform_write (on generic_perform_write+170 with a_ops)

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1431336304-16863-2-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-12 09:59:50 -03:00
He Kuang fb9596d173 perf probe: Remove length limitation for showing available variables
Use struct strbuf instead of bare char[] to remove the length limitation
of variables in variable_list, so they will not disappear due to
overlength, and make preparation for adding more description for
variables.

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1431336304-16863-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-12 09:59:49 -03:00
Masami Hiramatsu 4c85935122 perf probe: Support glob wildcards for function name
Support glob wildcards for function name when adding new probes. This
will allow us to build caches of function-entry level information with
$params.

e.g.
  ----
  # perf probe --no-inlines --add 'kmalloc* $params'
  Added new events:
    probe:kmalloc_slab   (on kmalloc* with $params)
    probe:kmalloc_large_node (on kmalloc* with $params)
    probe:kmalloc_order_trace (on kmalloc* with $params)

  You can now use it in all perf tools, such as:

        perf record -e probe:kmalloc_order_trace -aR sleep 1

  # perf probe --list
    probe:kmalloc_large_node (on kmalloc_large_node@mm/slub.c with size flags node)
    probe:kmalloc_order_trace (on kmalloc_order_trace@mm/slub.c with size flags order)
    probe:kmalloc_slab   (on kmalloc_slab@mm/slab_common.c with size flags)
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150508010335.24812.19972.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:31:02 -03:00
Masami Hiramatsu c72738355b perf probe: Fix to track down unnamed union/structure members
Fix 'perf probe' to track down unnamed union/structure members.

perf probe did not track down the tree of unnamed union/structure
members, since it just failed to find given "name" in a parent
structure/union.  To solve this issue, I've introduced 2 changes.

- Fix die_find_member() to track down the type-DIE if it is
  unnamed, and if it contains the specified member, returns the
  unnamed member.
  (note that we don't return found member, since unnamed member
   has the offset in the parent structure)
- Fix convert_variable_fields() to track down the unnamed union/
  structure (one-by-one).

With this patch, perf probe can access unnamed fields:
  -----
  #./perf probe -nfx ./perf lock__delete ops 'locked_ops=ops->locked.ops'
  Added new event:
    probe_perf:lock__delete (on lock__delete in /home/mhiramat/ksrc/linux-3/tools/perf/perf with ops locked_ops=ops->locked.ops)

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:lock__delete -aR sleep 1
  -----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Report-Link: https://lkml.org/lkml/2015/3/5/431
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150402073312.14482.37942.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-02 13:18:44 -03:00
Masami Hiramatsu e1ecbbc3fa perf probe: Fix to handle optimized not-inlined functions
Fix to handle optimized no-inline functions which have only function
definition but no actual instance at that point.

To fix this problem, we need to find actual instance of the function.

Without this patch:
  ----
  # perf probe -a __up
  Failed to get entry address of __up.
    Error: Failed to add events.
  # perf probe -L __up
  Specified source line is not found.
    Error: Failed to show lines.
  ----

With this patch:
  ----
  # perf probe -a __up
  Added new event:
    probe:__up           (on __up)

  You can now use it in all perf tools, such as:

          perf record -e probe:__up -aR sleep 1

  # perf probe -L __up
  <__up@/home/fedora/ksrc/linux-3/kernel/locking/semaphore.c:0>
        0  static noinline void __sched __up(struct semaphore *sem)
           {
                  struct semaphore_waiter *waiter = list_first_entry(&sem->wait_
                                                          struct semaphore_waite
        4         list_del(&waiter->list);
        5         waiter->up = true;
        6         wake_up_process(waiter->task);
        7  }
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150130093744.30575.43290.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-06 11:46:36 +01:00
Masami Hiramatsu 082f96a93e perf probe: Fix perf probe to find correct variable DIE
Fix perf probe to find correct variable DIE which has location or
external instance by tracking down the lexical blocks.

Current die_find_variable() expects that the all variable DIEs
which has DW_TAG_variable have a location. However, since recent
dwarf information may have declaration variable DIEs at the
entry of function (subprogram), die_find_variable() returns it.

To solve this problem, it must track down the DIE tree to find
a DIE which has an actual location or a reference for external
instance.

e.g. finding a DIE which origin is <0xdc73>;

 <1><11496>: Abbrev Number: 95 (DW_TAG_subprogram)
    <11497>   DW_AT_abstract_origin: <0xdc42>
    <1149b>   DW_AT_low_pc      : 0x1850
[...]
 <2><114cc>: Abbrev Number: 119 (DW_TAG_variable) <- this is a declaration
    <114cd>   DW_AT_abstract_origin: <0xdc73>
 <2><114d1>: Abbrev Number: 119 (DW_TAG_variable)
[...]
 <3><115a7>: Abbrev Number: 105 (DW_TAG_lexical_block)
    <115a8>   DW_AT_ranges      : 0xaa0
 <4><115ac>: Abbrev Number: 96 (DW_TAG_variable) <- this has a location
    <115ad>   DW_AT_abstract_origin: <0xdc73>
    <115b1>   DW_AT_location    : 0x486c        (location list)

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20140529121930.30879.87092.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
2014-06-04 14:49:20 +02:00
Masami Hiramatsu e08cfd4bda perf probe: Fix to find line information for probe list
Fix to find the correct (as much as possible) line information for
listing probes. Without this fix, perf probe --list action will show
incorrect line information as below;

  probe:getname_flags  (on getname_flags@ksrc/linux-3/fs/namei.c)
  probe:getname_flags_1 (on getname:-89@x86/include/asm/current.h)
  probe:getname_flags_2 (on user_path_at_empty:-2054@x86/include/asm/current.h)

The minus line number is obviously wrong, and current.h is not related
to the probe point. Deeper investigation discovered that there were 2
issues related to this bug, and minor typos too.

The 1st issue is the rack of considering about nested inlined functions,
which causes the wrong (relative) line number.

The 2nd issue is that the dwarf line info is not correct at those
points. It points 14th line of current.h.

Since it seems that the line info includes somewhat unreliable
information, this fixes perf to try to find correct line information
from both of debuginfo and line info as below.

1) Probe address is the entry of a function instance

  In this case, the line is set as the function declared line.

2) Probe address is the entry of an expanded inline function block

  In this case, the line is set as the function call-site line.
  This means that the line number is relative from the entry line
  of caller function (which can be an inlined function if nested)

3) Probe address is inside a function instance or an expanded
   inline function block

  In this case, perf probe queries the line number from lineinfo
  and verify the function declared file is same as the file name
  queried from lineinfo.

  If the file name is different, it is a failure case. The probe
  address is shown as symbol+offset.

4) Probe address is not in the any function instance

  This is a failure case, the probe address is shown as
  symbol+offset.

With this fix, perf probe -l shows correct probe lines as below;

  probe:getname_flags  (on getname_flags@ksrc/linux-3/fs/namei.c)
  probe:getname_flags_1 (on getname:2@ksrc/linux-3/fs/namei.c)
  probe:getname_flags_2 (on user_path_at_empty:4@ksrc/linux-3/fs/namei.c)

Changes at v2:
 - Fix typos in the function comments. (Thanks to Namhyung Kim)
 - Use die_find_top_inlinefunc instead of die_find_inlinefunc_next.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
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/20130930092144.1693.11058.stgit@udc4-manage.rcp.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-10-04 15:16:05 -03:00
Masami Hiramatsu 0dbb1cac1d perf probe: Fix finder to find lines of given function
The commit ba28c59bc9 fixed a declaration
entry bug in probe_point_search_cb().  There are same bugs in line
finder and call_probe_finder().  This introduces a new dwarf utility
function to determine given DIE is a function definition, not
declaration.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20120423032435.8737.80064.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-09-19 11:35:05 -03:00
Hyeoncheol Lee bb2d17a014 perf probe: Print an enum type variable in "enum variable-name" format when showing accessible variables
When showing accessible variables, an enum type variable was printed in
"variable-name" format. Change this format into "enum variable-name".

Signed-off-by: Hyeoncheol Lee <hyc.lee@gmail.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/1348713399-4541-1-git-send-email-hyc.lee@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-09-27 10:58:57 -03:00
Masami Hiramatsu 3f4460a28f perf probe: Filter out redundant inline-instances
With gcc4.6, some instances of concrete inlined function looks redundant
and broken, because it appears inside of a concrete instance and its
call_file and call_line are same as the original abstruct's decl_file
and decl_line respectively.

e.g.
 [  d1aa]    subprogram
             external             (flag) Yes
             name                 (strp) "add_timer"
             decl_file            (data1) 2		;here is original
             decl_line            (data2) 847		;line and file
             prototyped           (flag) Yes
             inline               (data1) inlined (1)
             sibling              (ref4) [  d1c6]
...
 [ 11d84]    subprogram
             abstract_origin      (ref4) [  d1aa]	; concrete instance
             low_pc               (addr) .text+0x000000000000246f <add_timer>
             high_pc              (addr) .text+0x000000000000248b <mod_timer_pending>
             frame_base           (block1)               [   0] call_frame_cfa
             sibling              (ref4) [ 11dd9]
 [ 11d9f]      formal_parameter
               abstract_origin      (ref4) [  d1b9]
               location             (data4) location list [  701b]
 [ 11da8]      inlined_subroutine
               abstract_origin      (ref4) [  d1aa]	; redundant instance
               low_pc               (addr) .text+0x000000000000247e <add_timer+0xf>
               high_pc              (addr) .text+0x0000000000002480 <add_timer+0x11>
               call_file            (data1) 2		; call line and file
               call_line            (data2) 847		; are same as above

Those redundant instances leads unwilling results;

e.g. find probe points inside of functions even if we specify
a function entry as below;

$ perf probe -V add_timer
Available variables at add_timer
        @<add_timer+0>
                struct timer_list*      timer
        @<add_timer+15>
                (No matched variables)

So, this filters out those redundant instances based on call-site and
decl-site information.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20110811110317.19900.59525.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-12 09:34:35 -03:00
Masami Hiramatsu db0d2c6420 perf probe: Search concrete out-of-line instances
gcc 4.6 generates a concrete out-of-line instance when there is a
function which is implicitly inlined somewhere but also has its own
instance. The concrete out-of-line instance means that it has an
abstract origin of the function which is referred by not only
inlined-subroutines but also a concrete subprogram.

Since current dwarf_func_inline_instances() can find only instances of
inlined-subroutines, this introduces new die_walk_instances() to find
both of subprogram and inlined-subroutines.

e.g. without this,
Available variables at sched_group_rt_period
        @<cpu_rt_period_read_uint+9>
                struct task_group*      tg

perf probe failed to find actual subprogram instance of
sched_group_rt_period().

With this,

Available variables at sched_group_rt_period
        @<cpu_rt_period_read_uint+9>
                struct task_group*      tg
        @<sched_group_rt_period+0>
                struct task_group*      tg

Now it found the sched_group_rt_period() itself.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20110811110311.19900.63997.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-12 09:32:10 -03:00
Masami Hiramatsu 221d061182 perf probe: Fix to search local variables in appropriate scope
Fix perf probe to search local variables in appropriate local inlined
function scope. For example, pre_schedule() has only 2 local variables,
as below;

$ perf probe -L pre_schedule
<pre_schedule@/home/mhiramat/ksrc/linux-2.6/kernel/sched.c:0>
      0  static inline void pre_schedule(struct rq *rq, struct task_struct *prev)
         {
      2         if (prev->sched_class->pre_schedule)
      3                 prev->sched_class->pre_schedule(rq, prev);
         }

However, current perf probe shows 4 local variables on pre_schedule(),
because it searches variables in the caller(schedule()) scope.

$ perf probe -V pre_schedule
Available variables at pre_schedule
        @<schedule+445>
                int     cpu
                long unsigned int*      switch_count
                struct rq*      rq
                struct task_struct*     prev

This patch fixes this issue by searching variables in the local scope of
the instance of inlined function. Here is the result.

$ perf probe -V pre_schedule
Available variables at pre_schedule
        @<schedule+445>
                struct rq*      rq
                struct task_struct*     prev

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20110811110259.19900.85664.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-12 09:28:45 -03:00
Masami Hiramatsu b0e9cb2802 perf probe: Fix to search nested inlined functions in CU
Fix perf probe to walk through the lines of all nested inlined function
call sites and declared lines when a whole CU is passed to the line
walker.

The die_walk_lines() can have two different type of DIEs, subprogram (or
inlined-subroutine) DIE and CU DIE.

If a caller passes a subprogram DIE, this means that the walker walk on
lines of given subprogram. In this case, it just needs to search on
direct children of DIE tree for finding call-site information of inlined
function which directly called from given subprogram.

On the other hand, if a caller passes a CU DIE to the walker, this means
that the walker have to walk on all lines in the source files included
in given CU DIE. In this case, it has to search whole DIE trees of all
subprograms to find the call-site information of all nested inlined
functions.

Without this patch:

$ perf probe --line kernel/cpu.c:151-157
</home/mhiramat/ksrc/linux-2.6/kernel/cpu.c:151>

         static int cpu_notify(unsigned long val, void *v)
         {
    154         return __cpu_notify(val, v, -1, NULL);
         }

With this:
$ perf probe --line kernel/cpu.c:151-157
</home/mhiramat/ksrc/linux-2.6/kernel/cpu.c:151>

    152  static int cpu_notify(unsigned long val, void *v)
         {
    154         return __cpu_notify(val, v, -1, NULL);
         }

As you can see, --line option with source line range shows the declared
lines as probe-able.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20110811110241.19900.34994.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-12 09:23:39 -03:00
Masami Hiramatsu a128405c6b perf probe: Fix line walker to check CU correctly
Fix line walker to check whether a given DIE is CU or not.

Actually this function accepts CU, subprogram and inlined_subroutine
DIEs.

Without this fix, perf probe always fails to analyze lines on inlined
functions;

$ perf probe -L pre_schedule
Debuginfo analysis failed. (-2)
  Error: Failed to show lines. (-2)

This fixes that bug, as below.

$ perf probe -L pre_schedule
<pre_schedule@/home/mhiramat/ksrc/linux-2.6/kernel/sched.c:0>
      0  static inline void pre_schedule(struct rq *rq, struct task_struct *prev
         {
      2         if (prev->sched_class->pre_schedule)
      3                 prev->sched_class->pre_schedule(rq, prev);
         }

         /* rq->lock is NOT held, but preemption is disabled */

Changes from v1:
 - Update against current tip tree.(Fix dwarf-aux.c)

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20110811110235.19900.20614.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-08-12 09:22:46 -03:00
Masami Hiramatsu e0d153c690 perf-probe: Move dwarf library routines to dwarf-aux.{c, h}
Move dwarf library related routines to dwarf-aux.{c,h}.
This includes several minor changes.
- Add simple documents for each API.
- Rename die_find_real_subprogram() to die_find_realfunc()
- Rename line_walk_handler_t to line_walk_callback_t.
- Minor cleanups.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Link: http://lkml.kernel.org/r/20110627072727.6528.57647.stgit@fedora15
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-07-15 16:10:17 -04:00