linux-stable.git/tools/perf, branch v5.4.7

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

2019-12-31T15:45:41+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

perf session: Fix decompression of PERF_RECORD_COMPRESSED records

2019-12-31T15:45:40+00:00

[ Upstream commit bb1835a3b86c73aa534ef6430ad40223728dfbc0 ]

Avoid termination of trace loading in case the last record in the
decompressed buffer partly resides in the following mmaped
PERF_RECORD_COMPRESSED record.

In this case NULL value returned by fetch_mmaped_event() means to
proceed to the next mmaped record then decompress it and load compressed
events.

The issue can be reproduced like this:

  $ perf record -z -- some_long_running_workload
  $ perf report --stdio -vv
  decomp (B): 44519 to 163000
  decomp (B): 48119 to 174800
  decomp (B): 65527 to 131072
  fetch_mmaped_event: head=0x1ffe0 event->header_size=0x28, mmap_size=0x20000: fuzzed perf.data?
  Error:
  failed to process sample
  ...

Testing:

  71: Zstd perf.data compression/decompression              : Ok

  $ tools/perf/perf report -vv --stdio
  decomp (B): 59593 to 262160
  decomp (B): 4438 to 16512
  decomp (B): 285 to 880
  Looking at the vmlinux_path (8 entries long)
  Using vmlinux for symbols
  decomp (B): 57474 to 261248
  prefetch_event: head=0x3fc78 event->header_size=0x28, mmap_size=0x3fc80: fuzzed or compressed perf.data?
  decomp (B): 25 to 32
  decomp (B): 52 to 120
  ...

Fixes: 57fc032ad643 ("perf session: Avoid infinite loop when seeing invalid header.size")
Link: https://marc.info/?l=linux-kernel&m=156580812427554&w=2
Co-developed-by: Jiri Olsa 
Acked-by: Jiri Olsa 
Signed-off-by: Alexey Budankov 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/cf782c34-f3f8-2f9f-d6ab-145cee0d5322@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

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

2019-12-31T15:45:05+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

2019-12-31T15:45:04+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

2019-12-31T15:45:04+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

2019-12-31T15:45:03+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

perf probe: Skip overlapped location on searching variables

2019-12-31T15:45:02+00:00

[ Upstream commit dee36a2abb67c175265d49b9a8c7dfa564463d9a ]

Since debuginfo__find_probes() callback function can be called with  the
location which already passed, the callback function must filter out
such overlapped locations.

add_probe_trace_event() has already done it by commit 1a375ae7659a
("perf probe: Skip same probe address for a given line"), but
add_available_vars() doesn't. Thus perf probe -v shows same address
repeatedly as below:

  # perf probe -V vfs_read:18
  Available variables at vfs_read:18
          @
                  char*   buf
                  loff_t* pos
                  ssize_t ret
                  struct file*    file
          @
                  char*   buf
                  loff_t* pos
                  ssize_t ret
                  struct file*    file
          @
                  char*   buf
                  loff_t* pos
                  ssize_t ret
                  struct file*    file

With this fix, perf probe -V shows it correctly:

  # perf probe -V vfs_read:18
  Available variables at vfs_read:18
          @
                  char*   buf
                  loff_t* pos
                  ssize_t ret
                  struct file*    file
          @
                  char*   buf
                  loff_t* pos
                  ssize_t ret
                  struct file*    file

Fixes: cf6eb489e5c0 ("perf probe: Show accessible local variables")
Signed-off-by: Masami Hiramatsu 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lore.kernel.org/lkml/157241938927.32002.4026859017790562751.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf parse: If pmu configuration fails free terms

2019-12-31T15:45:01+00:00

[ Upstream commit 38f2c4226e6bc3e8c41c318242821ba5dc825aba ]

Avoid a memory leak when the configuration fails.

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexei Starovoitov 
Cc: Andi Kleen 
Cc: Daniel Borkmann 
Cc: Jin Yao 
Cc: John Garry 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Martin KaFai Lau 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Yonghong Song 
Cc: bpf@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191030223448.12930-9-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf tools: Splice events onto evlist even on error

2019-12-31T15:44:58+00:00

[ Upstream commit 8e8714c3d157568b7a769917a5e05573bbaf5af0 ]

If event parsing fails the event list is leaked, instead splice the list
onto the out result and let the caller cleanup.

An example input for parse_events found by libFuzzer that reproduces
this memory leak is 'm{'.

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexei Starovoitov 
Cc: Andi Kleen 
Cc: Daniel Borkmann 
Cc: Jin Yao 
Cc: John Garry 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Martin KaFai Lau 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: Yonghong Song 
Cc: bpf@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191025180827.191916-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf tools: Fix cross compile for ARM64

2019-12-31T15:44:57+00:00

[ Upstream commit 71f699078b154fcb1c9162fd0208ada9ce532ffc ]

Currently when cross compiling perf tool for ARM64 on my x86 machine I
get this error:

  arch/arm64/util/sym-handling.c:9:10: fatal error: gelf.h: No such file or directory
   #include 

For the build, libelf is reported off:

  Auto-detecting system features:
  ...
  ...                        libelf: [ OFF ]

Indeed, test-libelf is not built successfully:

  more ./build/feature/test-libelf.make.output
  test-libelf.c:2:10: fatal error: libelf.h: No such file or directory
   #include 
          ^~~~~~~~~~
  compilation terminated.

I have no such problems natively compiling on ARM64, and I did not
previously have this issue for cross compiling. Fix by relocating the
gelf.h include.

Signed-off-by: John Garry 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/1573045254-39833-1-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin