linux.git/tools/perf, branch v3.12-rc4

Revert "perf symbols: Demangle cloned functions"

2013-09-29T14:12:54+00:00

This reverts commit de95ab53645a2f0015e0f68ee723f18dce2b8b51.

Markus Trippelsdorf reported that this commit broke 'perf top':

 > I just see a gray screen with no text at all. Sometimes the
 > following error messages are printed:
 >
 >  *** Error in `perf': invalid fastbin entry (free): 0x00000000029b18c0
 >  ***
 >  *** Error in `perf': malloc(): memory corruption (fast): 0x0000000000ee0b10 ***

While this code is fixable, the commit itself fails on several levels:

 - it should have been a separate helper function
 - why the heck does it do strchr() twice
 - it casts a const char * over into char *
 - sloppy style
 - it's not even a regression fix!

So lets revert it and re-try the patch in v3.13.

Reported-by: Markus Trippelsdorf 
Cc: Andi Kleen 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Linus Torvalds 
Signed-off-by: Ingo Molnar

perf symbols: Demangle cloned functions

2013-09-25T15:58:21+00:00

The libbfd C++ demangler doesn't seem to deal with cloned functions,
like symbol.clone.NUM.

Just strip the dot part before demangling and add it back later.

Signed-off-by: Andi Kleen 
Link: http://lkml.kernel.org/r/1378998998-10802-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Fix path unpopulated in machine__create_modules()

2013-09-25T15:48:24+00:00

In machine__create_modules() the 'path' char array was used in a call to
symbol__restricted_filename() without always being populated.

Signed-off-by: Adrian Hunter 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Mike Galbraith 
Cc: Namhyung Kim 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1379845338-29637-2-git-send-email-adrian.hunter@intel.com
[ Split patch removing unrelated conversion of sprintf to snprintf to perf/core ]
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Explicitly add libdl dependency

2013-09-25T15:39:27+00:00

Fixes compile failure on Fedora 12.

Signed-off-by: David Ahern 
Link: http://lkml.kernel.org/r/1379900700-5186-3-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Fix probing symbols with optimization suffix

2013-09-25T15:27:31+00:00

Fix perf probe to probe on some symbols which have some optimzation
suffixes, e.g. ".part", ".isra", and ".constprop".

To fix this issue, instead of using the DIE name, perf probe uses the
symbol name found by dwfl_module_addrsym().

This also involves a perf probe --vars operation update which now shows
the symbol name instead of the DIE name.

Without this patch, putting a probe on an inlined function which was
compiled with a suffixed symbol will fail like this:

  $ perf probe -v getname_flags
  probe-definition(0): getname_flags
  symbol:getname_flags file:(null) line:0 offset:0 return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (6 entries long)
  Using /lib/modules/3.11.0+/build/vmlinux for symbols
  found inline addr: 0xffffffff8119bb70
  Probe point found: getname_flags+0
  found inline addr: 0xffffffff8119bcb6
  Probe point found: getname+6
  found inline addr: 0xffffffff811a06a6
  Probe point found: user_path_at_empty+6
  find 3 probe_trace_events.
  Opening /sys/kernel/debug//tracing/kprobe_events write=1
  Added new events:
  Writing event: p:probe/getname_flags getname_flags+0
  Failed to write event: No such file or directory
    Error: Failed to add events. (-1)

Because the debuginfo knows only the original (non suffix) symbol name,
it uses the original symbol for probe address but the kernel (kallsyms)
knows only suffixed symbol.  Then, the kernel rejects that original
symbol.

This patch uses dwfl_module_addrsym() to get the correct (suffixed)
symbol from symtab when a probe point is found.

Reported-by: Arnaldo Carvalho de Melo 
Signed-off-by: Masami Hiramatsu 
Cc: Ingo Molnar 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20130925131616.31632.46658.stgit@udc4-manage.rcp.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo

perf trace: Add mmap2 handler

2013-09-24T17:15:51+00:00

5c5e854b changed perf_event__synthesize_mmap_events to generate MMAP2
events. Since perf-trace does not have a handler for it it dies with a
segfault when trying to process files:

perf trace -i /tmp/perf.data
Segmentation fault

Signed-off-by: David Ahern 
Link: http://lkml.kernel.org/r/1379900700-5186-4-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf kmem: Make it work again on non NUMA machines

2013-09-24T17:13:46+00:00

The commit '2814eb0 perf kmem: Remove die() calls' disabled 'perf kmem'
command for machines without numa support. It made the command fail if
'/sys/devices/system/node' dir wasn't found.

Skipping the numa based initialization in case the directory is not
found and continue execution.

Signed-off-by: Jiri Olsa 
Cc: Corey Ashford 
Cc: Frederic Weisbecker 
Cc: Namhyung Kim 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1379003976-5839-5-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo

perf: Fix capabilities bitfield compatibility in 'struct perf_event_mmap_page'

2013-09-20T07:45:11+00:00

Solve the problems around the broken definition of perf_event_mmap_page::
cap_usr_time and cap_usr_rdpmc fields which used to overlap, partially
fixed by:

  860f085b74e9 ("perf: Fix broken union in 'struct perf_event_mmap_page'")

The problem with the fix (merged in v3.12-rc1 and not yet released
officially), noticed by Vince Weaver is that the new behavior is
not detectable by new user-space, and that due to the reuse of the
field names it's easy to mis-compile a binary if old headers are used
on a new kernel or new headers are used on an old kernel.

To solve all that make this change explicit, detectable and self-contained,
by iterating the ABI the following way:

 - Always clear bit 0, and rename it to usrpage->cap_bit0, to at least not
   confuse old user-space binaries. RDPMC will be marked as unavailable
   to old binaries but that's within the ABI, this is a capability bit.

 - Rename bit 1 to ->cap_bit0_is_deprecated and always set it to 1, so new
   libraries can reliably detect that bit 0 is deprecated and perma-zero
   without having to check the kernel version.

 - Use bits 2, 3, 4 for the newly defined, correct functionality:

	cap_user_rdpmc		: 1, /* The RDPMC instruction can be used to read counts */
	cap_user_time		: 1, /* The time_* fields are used */
	cap_user_time_zero	: 1, /* The time_zero field is used */

 - Rename all the bitfield names in perf_event.h to be different from the
   old names, to make sure it's not possible to mis-compile it
   accidentally with old assumptions.

The 'size' field can then be used in the future to add new fields and it
will act as a natural ABI version indicator as well.

Also adjust tools/perf/ userspace for the new definitions, noticed by
Adrian Hunter.

Reported-by: Vince Weaver 
Signed-off-by: Peter Zijlstra 
Also-Fixed-by: Adrian Hunter 
Link: http://lkml.kernel.org/n/tip-zr03yxjrpXesOzzupszqglbv@git.kernel.org
Signed-off-by: Ingo Molnar

perf tools: Fix old GCC build error in trace-event-parse.c:parse_proc_kallsyms()

2013-09-19T18:08:47+00:00

Old GCC (4.1) does not see through the code flow of parse_proc_kallsyms()
and gets confused about the status of 'fmt':

 util/trace-event-parse.c: In function ‘parse_proc_kallsyms’:
 util/trace-event-parse.c:189: warning: ‘fmt’ may be used uninitialized in this function
 make: *** [util/trace-event-parse.o] Error 1

Help out GCC by initializing 'fmt' to NULL.

Signed-off-by: Ingo Molnar 
Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: H. Peter Anvin 
Cc: Jiri Olsa 
Cc: Mike Galbraith 
Cc: Namhyung Kim 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20130912131649.GC23826@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Fix finder to find lines of given function

2013-09-19T14:35:05+00:00

The commit ba28c59bc9ed8fb7b9a753cd88ee54a2c4f6265b 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 
Cc: Ananth N Mavinakayanahalli 
Cc: Prashanth Nageshappa 
Cc: Srikar Dronamraju 
Cc: Steven Rostedt 
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