linux-stable.git/tools, branch v4.4.211

perf probe: Fix wrong address verification

2020-01-23T07:18:41+00:00

commit 07d369857808b7e8e471bbbbb0074a6718f89b31 upstream.

Since there are some DIE which has only ranges instead of the
combination of entrypc/highpc, address verification must use
dwarf_haspc() instead of dwarf_entrypc/dwarf_highpc.

Also, the ranges only DIE will have a partial code in different section
(e.g. unlikely code will be in text.unlikely as "FUNC.cold" symbol). In
that case, we can not use dwarf_entrypc() or die_entrypc(), because the
offset from original DIE can be a minus value.

Instead, this simply gets the symbol and offset from symtab.

Without this patch;

  # perf probe -D clear_tasks_mm_cpumask:1
  Failed to get entry address of clear_tasks_mm_cpumask
    Error: Failed to add events.

And with this patch:

  # perf probe -D clear_tasks_mm_cpumask:1
  p:probe/clear_tasks_mm_cpumask clear_tasks_mm_cpumask+0
  p:probe/clear_tasks_mm_cpumask_1 clear_tasks_mm_cpumask+5
  p:probe/clear_tasks_mm_cpumask_2 clear_tasks_mm_cpumask+8
  p:probe/clear_tasks_mm_cpumask_3 clear_tasks_mm_cpumask+16
  p:probe/clear_tasks_mm_cpumask_4 clear_tasks_mm_cpumask+82

Committer testing:

I managed to reproduce the above:

  [root@quaco ~]# perf probe -D clear_tasks_mm_cpumask:1
  p:probe/clear_tasks_mm_cpumask _text+919968
  p:probe/clear_tasks_mm_cpumask_1 _text+919973
  p:probe/clear_tasks_mm_cpumask_2 _text+919976
  [root@quaco ~]#

But then when trying to actually put the probe in place, it fails if I
use :0 as the offset:

  [root@quaco ~]# perf probe -L clear_tasks_mm_cpumask | head -5
  
        0  void clear_tasks_mm_cpumask(int cpu)
        1  {
        2  	struct task_struct *p;

  [root@quaco ~]# perf probe clear_tasks_mm_cpumask:0
  Probe point 'clear_tasks_mm_cpumask' not found.
    Error: Failed to add events.
  [root@quaco

The next patch is needed to fix this case.

Fixes: 576b523721b7 ("perf probe: Fix probing symbols with optimization suffix")
Reported-by: Arnaldo Carvalho de Melo 
Tested-by: Arnaldo Carvalho de Melo 
Signed-off-by: Masami Hiramatsu 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/157199318513.8075.10463906803299647907.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Greg Kroah-Hartman

rseq/selftests: Turn off timeout setting

2020-01-23T07:18:38+00:00

[ Upstream commit af9cb29c5488381083b0b5ccdfb3cd931063384a ]

As the rseq selftests can run for a long period of time, disable the
timeout that the general selftests have.

Signed-off-by: Mathieu Desnoyers 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: Peter Zijlstra (Intel) 
Cc: "Paul E. McKenney" 
Cc: Boqun Feng 
Cc: "H . Peter Anvin" 
Cc: Paul Turner 
Cc: Dmitry Vyukov 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

Revert "perf report: Add warning when libunwind not compiled in"

2020-01-12T10:22:41+00:00

This reverts commit 59b706ce44dbfd35a428f2cbad47794ce5dce1eb.

This change depends on more changes that didn't exist in 4.9 and older.

Signed-off-by: Sasha Levin

perf regs: Make perf_reg_name() return "unknown" instead of NULL

2020-01-04T12:34:37+00:00

[ Upstream commit 5b596e0ff0e1852197d4c82d3314db5e43126bf7 ]

To avoid breaking the build on arches where this is not wired up, at
least all the other features should be made available and when using
this specific routine, the "unknown" should point the user/developer to
the need to wire this up on this particular hardware architecture.

Detected in a container mipsel debian cross build environment, where it
shows up as:

  In file included from /usr/mipsel-linux-gnu/include/stdio.h:867,
                   from /git/linux/tools/perf/lib/include/perf/cpumap.h:6,
                   from util/session.c:13:
  In function 'printf',
      inlined from 'regs_dump__printf' at util/session.c:1103:3,
      inlined from 'regs__printf' at util/session.c:1131:2:
  /usr/mipsel-linux-gnu/include/bits/stdio2.h:107:10: error: '%-5s' directive argument is null [-Werror=format-overflow=]
    107 |   return __printf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ());
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

cross compiler details:

  mipsel-linux-gnu-gcc (Debian 9.2.1-8) 9.2.1 20190909

Also on mips64:

  In file included from /usr/mips64-linux-gnuabi64/include/stdio.h:867,
                   from /git/linux/tools/perf/lib/include/perf/cpumap.h:6,
                   from util/session.c:13:
  In function 'printf',
      inlined from 'regs_dump__printf' at util/session.c:1103:3,
      inlined from 'regs__printf' at util/session.c:1131:2,
      inlined from 'regs_user__printf' at util/session.c:1139:3,
      inlined from 'dump_sample' at util/session.c:1246:3,
      inlined from 'machines__deliver_event' at util/session.c:1421:3:
  /usr/mips64-linux-gnuabi64/include/bits/stdio2.h:107:10: error: '%-5s' directive argument is null [-Werror=format-overflow=]
    107 |   return __printf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ());
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  In function 'printf',
      inlined from 'regs_dump__printf' at util/session.c:1103:3,
      inlined from 'regs__printf' at util/session.c:1131:2,
      inlined from 'regs_intr__printf' at util/session.c:1147:3,
      inlined from 'dump_sample' at util/session.c:1249:3,
      inlined from 'machines__deliver_event' at util/session.c:1421:3:
  /usr/mips64-linux-gnuabi64/include/bits/stdio2.h:107:10: error: '%-5s' directive argument is null [-Werror=format-overflow=]
    107 |   return __printf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ());
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

cross compiler details:

  mips64-linux-gnuabi64-gcc (Debian 9.2.1-8) 9.2.1 20190909

Fixes: 2bcd355b71da ("perf tools: Add interface to arch registers sets")
Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lkml.kernel.org/n/tip-95wjyv4o65nuaeweq31t7l1s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf probe: Fix to show function entry line as probe-able

2020-01-04T12:34:23+00:00

commit 91e2f539eeda26ab00bd03fae8dc434c128c85ed upstream.

Fix die_walk_lines() to list the function entry line correctly.  Since
the dwarf_entrypc() does not return the entry pc if the DIE has only
range attribute, __die_walk_funclines() fails to list the declaration
line (entry line) in that case.

To solve this issue, this introduces die_entrypc() which correctly
returns the entry PC (the first address range) even if the DIE has only
range attribute. With this fix die_walk_lines() shows the function entry
line is able to probe correctly.

Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface")
Signed-off-by: Masami Hiramatsu 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/157190837419.1859.4619125803596816752.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Thomas Backlund 
Signed-off-by: Greg Kroah-Hartman

libtraceevent: Fix memory leakage in copy_filter_type

2020-01-04T12:34:17+00:00

[ Upstream commit 10992af6bf46a2048ad964985a5b77464e5563b1 ]

It is necessary to free the memory that we have allocated when error occurs.

Fixes: ef3072cd1d5c ("tools lib traceevent: Get rid of die in add_filter_type()")
Signed-off-by: Hewenliang 
Reviewed-by: Steven Rostedt (VMware) 
Cc: Tzvetomir Stoyanov 
Link: http://lore.kernel.org/lkml/20191119014415.57210-1-hewenliang4@huawei.com
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf probe: Filter out instances except for inlined subroutine and subprogram

2020-01-04T12:34:15+00:00

[ Upstream commit da6cb952a89efe24bb76c4971370d485737a2d85 ]

Filter out instances except for inlined_subroutine and subprogram DIE in
die_walk_instances() and die_is_func_instance().

This fixes an issue that perf probe sets some probes on calling address
instead of a target function itself.

When perf probe walks on instances of an abstruct origin (a kind of
function prototype of inlined function), die_walk_instances() can also
pass a GNU_call_site (a GNU extension for call site) to callback. Since
it is not an inlined instance of target function, we have to filter out
when searching a probe point.

Without this patch, perf probe sets probes on call site address too.This
can happen on some function which is marked "inlined", but has actual
symbol. (I'm not sure why GCC mark it "inlined"):

  # perf probe -D vfs_read
  p:probe/vfs_read _text+2500017
  p:probe/vfs_read_1 _text+2499468
  p:probe/vfs_read_2 _text+2499563
  p:probe/vfs_read_3 _text+2498876
  p:probe/vfs_read_4 _text+2498512
  p:probe/vfs_read_5 _text+2498627

With this patch:

Slightly different results, similar tho:

  # perf probe -D vfs_read
  p:probe/vfs_read _text+2498512

Committer testing:

  # uname -a
  Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

Before:

  # perf probe -D vfs_read
  p:probe/vfs_read _text+3131557
  p:probe/vfs_read_1 _text+3130975
  p:probe/vfs_read_2 _text+3131047
  p:probe/vfs_read_3 _text+3130380
  p:probe/vfs_read_4 _text+3130000
  # uname -a
  Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
  #

After:

  # perf probe -D vfs_read
  p:probe/vfs_read _text+3130000
  #

Fixes: db0d2c6420ee ("perf probe: Search concrete out-of-line instances")
Signed-off-by: Masami Hiramatsu 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/157241937063.32002.11024544873990816590.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf probe: Skip end-of-sequence and non statement lines

2020-01-04T12:34:15+00:00

[ Upstream commit f4d99bdfd124823a81878b44b5e8750b97f73902 ]

Skip end-of-sequence and non-statement lines while walking through lines
list.

The "end-of-sequence" line information means:

 "the current address is that of the first byte after the
  end of a sequence of target machine instructions."
 (DWARF version 4 spec 6.2.2)

This actually means out of scope and we can not probe on it.

On the other hand, the statement lines (is_stmt) means:

 "the current instruction is a recommended breakpoint location.
  A recommended breakpoint location is intended to “represent”
  a line, a statement and/or a semantically distinct subpart
  of a statement."

 (DWARF version 4 spec 6.2.2)

So, non-statement line info also should be skipped.

These can reduce unneeded probe points and also avoid an error.

E.g. without this patch:

  # perf probe -a "clear_tasks_mm_cpumask:1"
  Added new events:
    probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1)
    probe:clear_tasks_mm_cpumask_1 (on clear_tasks_mm_cpumask:1)
    probe:clear_tasks_mm_cpumask_2 (on clear_tasks_mm_cpumask:1)
    probe:clear_tasks_mm_cpumask_3 (on clear_tasks_mm_cpumask:1)
    probe:clear_tasks_mm_cpumask_4 (on clear_tasks_mm_cpumask:1)

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

  	perf record -e probe:clear_tasks_mm_cpumask_4 -aR sleep 1

  #

This puts 5 probes on one line, but acutally it's not inlined function.
This is because there are many non statement instructions at the
function prologue.

With this patch:

  # perf probe -a "clear_tasks_mm_cpumask:1"
  Added new event:
    probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1)

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

  	perf record -e probe:clear_tasks_mm_cpumask -aR sleep 1

  #

Now perf-probe skips unneeded addresses.

Committer testing:

Slightly different results, but similar:

Before:

  # uname -a
  Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
  #
  # perf probe -a "clear_tasks_mm_cpumask:1"
  Added new events:
    probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1)
    probe:clear_tasks_mm_cpumask_1 (on clear_tasks_mm_cpumask:1)
    probe:clear_tasks_mm_cpumask_2 (on clear_tasks_mm_cpumask:1)

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

  	perf record -e probe:clear_tasks_mm_cpumask_2 -aR sleep 1

  #

After:

  # perf probe -a "clear_tasks_mm_cpumask:1"
  Added new event:
    probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1)

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

  	perf record -e probe:clear_tasks_mm_cpumask -aR sleep 1

  # perf probe -l
    probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask@kernel/cpu.c)
  #

Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface")
Signed-off-by: Masami Hiramatsu 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/157241936090.32002.12156347518596111660.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf probe: Fix to show calling lines of inlined functions

2020-01-04T12:34:15+00:00

[ Upstream commit 86c0bf8539e7f46d91bd105e55eda96e0064caef ]

Fix to show calling lines of inlined functions (where an inline function
is called).

die_walk_lines() filtered out the lines inside inlined functions based
on the address. However this also filtered out the lines which call
those inlined functions from the target function.

To solve this issue, check the call_file and call_line attributes and do
not filter out if it matches to the line information.

Without this fix, perf probe -L doesn't show some lines correctly.
(don't see the lines after 17)

  # perf probe -L vfs_read
  
        0  ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
        1  {
        2         ssize_t ret;

        4         if (!(file->f_mode & FMODE_READ))
                          return -EBADF;
        6         if (!(file->f_mode & FMODE_CAN_READ))
                          return -EINVAL;
        8         if (unlikely(!access_ok(buf, count)))
                          return -EFAULT;

       11         ret = rw_verify_area(READ, file, pos, count);
       12         if (!ret) {
       13                 if (count > MAX_RW_COUNT)
                                  count =  MAX_RW_COUNT;
       15                 ret = __vfs_read(file, buf, count, pos);
       16                 if (ret > 0) {
                                  fsnotify_access(file);
                                  add_rchar(current, ret);
                          }

With this fix:

  # perf probe -L vfs_read
  
        0  ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
        1  {
        2         ssize_t ret;

        4         if (!(file->f_mode & FMODE_READ))
                          return -EBADF;
        6         if (!(file->f_mode & FMODE_CAN_READ))
                          return -EINVAL;
        8         if (unlikely(!access_ok(buf, count)))
                          return -EFAULT;

       11         ret = rw_verify_area(READ, file, pos, count);
       12         if (!ret) {
       13                 if (count > MAX_RW_COUNT)
                                  count =  MAX_RW_COUNT;
       15                 ret = __vfs_read(file, buf, count, pos);
       16                 if (ret > 0) {
       17                         fsnotify_access(file);
       18                         add_rchar(current, ret);
                          }
       20                 inc_syscr(current);
                  }

Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface")
Signed-off-by: Masami Hiramatsu 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/157241937995.32002.17899884017011512577.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf probe: Return a better scope DIE if there is no best scope

2020-01-04T12:34:15+00:00

[ Upstream commit c701636aeec4c173208697d68da6e4271125564b ]

Make find_best_scope() returns innermost DIE at given address if there
is no best matched scope DIE. Since Gcc sometimes generates intuitively
strange line info which is out of inlined function address range, we
need this fixup.

Without this, sometimes perf probe failed to probe on a line inside an
inlined function:

  # perf probe -D ksys_open:3
  Failed to find scope of probe point.
    Error: Failed to add events.

With this fix, 'perf probe' can probe it:

  # perf probe -D ksys_open:3
  p:probe/ksys_open _text+25707308
  p:probe/ksys_open_1 _text+25710596
  p:probe/ksys_open_2 _text+25711114
  p:probe/ksys_open_3 _text+25711343
  p:probe/ksys_open_4 _text+25714058
  p:probe/ksys_open_5 _text+2819653
  p:probe/ksys_open_6 _text+2819701

Signed-off-by: Masami Hiramatsu 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Namhyung Kim 
Cc: Ravi Bangoria 
Cc: Steven Rostedt (VMware) 
Cc: Tom Zanussi 
Link: http://lore.kernel.org/lkml/157291300887.19771.14936015360963292236.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin