If the kernel is compiled with gcc 4.6.0 which supports -mfentry,
then use that instead of mcount.
With mcount, frame pointers are forced with the -pg option and we
get something like:
<can_vma_merge_before>:
55 push %rbp
48 89 e5 mov %rsp,%rbp
53 push %rbx
41 51 push %r9
e8 fe 6a 39 00 callq ffffffff81483d00 <mcount>
31 c0 xor %eax,%eax
48 89 fb mov %rdi,%rbx
48 89 d7 mov %rdx,%rdi
48 33 73 30 xor 0x30(%rbx),%rsi
48 f7 c6 ff ff ff f7 test $0xfffffffff7ffffff,%rsi
With -mfentry, frame pointers are no longer forced and the call looks
like this:
<can_vma_merge_before>:
e8 33 af 37 00 callq ffffffff81461b40 <__fentry__>
53 push %rbx
48 89 fb mov %rdi,%rbx
31 c0 xor %eax,%eax
48 89 d7 mov %rdx,%rdi
41 51 push %r9
48 33 73 30 xor 0x30(%rbx),%rsi
48 f7 c6 ff ff ff f7 test $0xfffffffff7ffffff,%rsi
This adds the ftrace hook at the beginning of the function before a
frame is set up, and allows the function callbacks to be able to access
parameters. As kprobes now can use function tracing (at least on x86)
this speeds up the kprobe hooks that are at the beginning of the
function.
Link: http://lkml.kernel.org/r/20120807194100.130477900@goodmis.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Thanks to Andi Kleen, gcc 4.6.0 now supports -mfentry for x86
(and hopefully soon for other archs). What this does is to have
the function profiler start at the beginning of the function
instead of after the stack is set up. As plain -pg (mcount) is
called after the stack is set up, and in some cases can have issues
with the function graph tracer. It also requires frame pointers to
be enabled.
The -mfentry now calls __fentry__ at the beginning of the function.
This allows for compiling without frame pointers and even has the
ability to access parameters if needed.
If the architecture and the compiler both support -mfentry then
use that instead.
Link: http://lkml.kernel.org/r/20120807194059.392617243@goodmis.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
* Fix include order for bison/flex-generated C files, from Ben Hutchings
* Build fixes and documentation corrections from David Ahern
* Group parsing support, from Jiri Olsa
* UI/gtk refactorings and improvements from Namhyung Kim
* NULL deref fix for perf script, from Namhyung Kim
* Assorted cleanups from Robert Richter
* Let O= makes handle relative paths, from Steven Rostedt
* perf script python fixes, from Feng Tang.
* Improve 'perf lock' error message when the needed tracepoints
are not present, from David Ahern.
* Initial bash completion support, from Frederic Weisbecker
* Allow building without libelf, from Namhyung Kim.
* Support DWARF CFI based unwind to have callchains when %bp
based unwinding is not possible, from Jiri Olsa.
* Symbol resolution fixes, while fixing support PPC64 files with an .opt ELF
section was the end goal, several fixes for code that handles all
architectures and cleanups are included, from Cody Schafer.
* Add a description for the JIT interface, from Andi Kleen.
* Assorted fixes for Documentation and build in 32 bit, from Robert Richter
* Add support for non-tracepoint events in perf script python, from Feng Tang
* Cache the libtraceevent event_format associated to each evsel early, so that we
avoid relookups, i.e. calling pevent_find_event repeatedly when processing
tracepoint events.
[ This is to reduce the surface contact with libtraceevents and make clear what
is that the perf tools needs from that lib: so far parsing the common and per
event fields. ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull ftrace updates from Steve Rostedt:
" This patch series extends ftrace function tracing utility to be
more dynamic for its users. It allows for data passing to the callback
functions, as well as reading regs as if a breakpoint were to trigger
at function entry.
The main goal of this patch series was to allow kprobes to use ftrace
as an optimized probe point when a probe is placed on an ftrace nop.
With lots of help from Masami Hiramatsu, and going through lots of
iterations, we finally came up with a good solution. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Build currently fails:
$ make -C tools/perf O=/tmp/pbuild NO_LIBELF=1
util/symbol.c: In function ‘dso__load’:
util/symbol.c:1128:27: error: ‘struct symsrc’ has no member named ‘dynsym’
CC /tmp/pbuild/util/pager.o
make: *** [/tmp/pbuild/util/symbol.o] Error 1
make: *** Waiting for unfinished jobs....
Moving the dynsym reference to symbol-elf.c reveals that NO_LIBELF requires
NO_LIBUNWIND:
$ make -C tools/perf O=/tmp/pbuild NO_LIBELF=1
LINK /tmp/pbuild/perf
/tmp/pbuild/libperf.a(unwind.o): In function `elf_section_offset':
/opt/sw/ahern/perf.git/tools/perf/util/unwind.c:176: undefined reference to `elf_begin'
/opt/sw/ahern/perf.git/tools/perf/util/unwind.c:181: undefined reference to `gelf_getehdr'
/tmp/pbuild/libperf.a(unwind.o): In function `elf_section_by_name':
/opt/sw/ahern/perf.git/tools/perf/util/unwind.c:157: undefined reference to `elf_nextscn'
/opt/sw/ahern/perf.git/tools/perf/util/unwind.c:160: undefined reference to `gelf_getshdr'
/opt/sw/ahern/perf.git/tools/perf/util/unwind.c:161: undefined reference to `elf_strptr'
/tmp/pbuild/libperf.a(unwind.o): In function `elf_section_offset':
/opt/sw/ahern/perf.git/tools/perf/util/unwind.c:190: undefined reference to `elf_end'
/tmp/pbuild/libperf.a(unwind.o): In function `read_unwind_spec':
/opt/sw/ahern/perf.git/tools/perf/util/unwind.c:190: undefined reference to `elf_end'
collect2: ld returned 1 exit status
make: *** [/tmp/pbuild/perf] Error 1
make: Leaving directory `/opt/sw/ahern/perf.git/tools/perf'
This patch fixes both.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1345391234-71906-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If GTK2 development packages are not installed, make is rather noisy:
$ make -C tools/perf O=/tmp/pbuild
Package gtk+-2.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `gtk+-2.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'gtk+-2.0' found
make: Entering directory `/opt/sw/ahern/perf.git/tools/perf'
Makefile:593: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev
PERF_VERSION = 3.6.rc1.205.gdb146f.dirty
make: Leaving directory `/opt/sw/ahern/perf.git/tools/perf'
Package gtk+-2.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `gtk+-2.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'gtk+-2.0' found
make: Entering directory `/opt/sw/ahern/perf.git/tools/perf'
Makefile:593: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev
...
Silence the pkg-config errors. Aftewards:
$ make -C tools/perf O=/tmp/pbuild
make: Entering directory `/opt/sw/ahern/perf.git/tools/perf'
Makefile:593: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev
PERF_VERSION = 3.6.rc1.206.gd43ff9.dirty
make: Leaving directory `/opt/sw/ahern/perf.git/tools/perf'
make: Entering directory `/opt/sw/ahern/perf.git/tools/perf'
Makefile:593: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev
...
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/1345391202-71865-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When I did a compile of perf using a relative path for the output
directory, the build failed when it tried to compile libtraceevent. This
is because it continues to use the same relative path when the new
working directory is in a different path.
SUBDIR ../lib/traceevent/
/bin/sh: line 0: cd: ../../../nobackup/perf/: No such file or directory
Makefile:74: *** output directory "../../../nobackup/perf/" does not exist. Stop.
make: *** [../../../nobackup/perf///libtraceevent.a] Error 2
Make the path used an absolute path when building perf with O=.
Boris:
Teach Makefile to check whether the supplied O= directory exists and
bail out if not. Reportedly, kernel dudes are idiots and need to be
guarded so as not to shoot themselves in the foot when playing in the
sandbox.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120815163923.GD15989@aftab.osrc.amd.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Just like was done for parse_events__set_leader.
Also we need to have the list_entry set_leader method in evlist.c so that we
don't grow another dep in the python binding:
# ~acme/git/linux/tools/perf/python/twatch.py
Traceback (most recent call last):
File "/home/acme/git/linux/tools/perf/python/twatch.py", line 16, in <module>
import perf
ImportError: /home/acme/git/build/perf/python/perf.so: undefined symbol: parse_events__set_leader
And also remove a pr_debug from evsel.c so that we avoid this one too:
# ~acme/git/linux/tools/perf/python/twatch.py
Traceback (most recent call last):
File "/home/acme/git/linux/tools/perf/python/twatch.py", line 16, in <module>
import perf
ImportError: /home/acme/git/build/perf/python/perf.so: undefined symbol: eprintf
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-0hk9dazg9pora9jylkqngovm@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch adds a functionality that allows to create event groups
based on the way they are specified on the command line. Adding
functionality to the '{}' group syntax introduced in earlier patch.
The current '--group/-g' option behaviour remains intact. If you
specify it for record/stat/top command, all the specified events
become members of a single group with the first event as a group
leader.
With the new '{}' group syntax you can create group like:
# perf record -e '{cycles,faults}' ls
resulting in single event group containing 'cycles' and 'faults'
events, with cycles event as group leader.
All groups are created with regards to threads and cpus. Thus
recording an event group within a 2 threads on server with
4 CPUs will create 8 separate groups.
Examples (first event in brackets is group leader):
# 1 group (cpu-clock,task-clock)
perf record --group -e cpu-clock,task-clock ls
perf record -e '{cpu-clock,task-clock}' ls
# 2 groups (cpu-clock,task-clock) (minor-faults,major-faults)
perf record -e '{cpu-clock,task-clock},{minor-faults,major-faults}' ls
# 1 group (cpu-clock,task-clock,minor-faults,major-faults)
perf record --group -e cpu-clock,task-clock -e minor-faults,major-faults ls
perf record -e '{cpu-clock,task-clock,minor-faults,major-faults}' ls
# 2 groups (cpu-clock,task-clock) (minor-faults,major-faults)
perf record -e '{cpu-clock,task-clock} -e '{minor-faults,major-faults}' \
-e instructions ls
# 1 group
# (cpu-clock,task-clock,minor-faults,major-faults,instructions)
perf record --group -e cpu-clock,task-clock \
-e minor-faults,major-faults -e instructions ls perf record -e
'{cpu-clock,task-clock,minor-faults,major-faults,instructions}' ls
It's possible to use standard event modifier for a group, which spans
over all events in the group and updates each event modifier settings,
for example:
# perf record -r '{faults:k,cache-references}:p'
resulting in ':kp' modifier being used for 'faults' and ':p' modifier
being used for 'cache-references' event.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/n/tip-ho42u0wcr8mn1otkalqi13qp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding support to update already defined event's attribute with
event modifier. This change will allow to use group modifier as
an update to the existing event modifiers.
Adding 'add' parameter to the parse_events__modifier_event function.
Calling it with 'add' = false/true, the event modifier is
initialized/updated respectively.
Added exclude_GH flag to evsel struct, because we need to remember
if one of 'GH' modifiers was used for event. The reason is that the
default settings for exclude_guest is 1 and during the group
modifier processing we have no other way of knowing if it was set
by default or by event modifier.
Keeping the current behaviour, that any event/group modifier reset
the defaults for exclude_host (0) and exclude_guest (1).
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/n/tip-8peaey3e2qc9dwtkvzbi4wmx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding scanner/parser bits to parse event groups.
The grammar for group is:
groups: groups ',' group | group
group: group_name '{' events '}' group_mod
group_name: name | empty
group_mod: ':' group_mods | empty
group_mods: event_mod
It's possible to use standard event modifier as a modifier
for group. It'll be used as an update to existing event
modifiers.
It's necessary to use quoting ("'\) when specifying group on
command line, since {} characters are interpreted by most of
the shells.
It is now possible to specify groups in event syntax like:
'{cycles,faults}'
- anonymous group
'group1{cycles,faults}
- group with name 'group1'
'{cycles,faults}:k
- anonymous group with event modifier 'k'
'{cpu-clock,task-clock},{minor-faults,major-faults}'
- two anonymous groups
The grouping functionality itself is coming shortly.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/n/tip-p4j8bnvo879uokum4k4zk5q6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We keep both a 'runtime' elf image as well as a 'debug' elf image around
and generate symbols by looking at both of these.
This eliminates the need for the want_symtab/goto restart mechanism
combined with iterating over and reopening the elf images a second time.
Also give dso__synthsize_plt_symbols() the runtime image (which has
dynsyms) instead of the symbol image (which may only have a symtab and
no dynsyms).
Previously if a debug image was found all runtime images were ignored.
This fixes 2 issues:
- Symbol resolution to failure on PowerPC systems with debug symbols
installed, as the debug images lack a '.opd' section which contains
function descriptors.
- On all archs, plt synthesis failed when a debug image was loaded and
that debug image lacks a dynsym section while a runtime image has a
dynsym section.
Assumptions:
- If a .opd section exists, it is contained in the highest priority
image with a dynsym section.
- This generally implies that the debug image lacks a dynsym section
(ie: it is marked as NO_BITS).
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: David Hansen <dave@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Matt Hellsley <matthltc@us.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1344637382-22789-17-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To properly handle platforms with an opd section, both a runtime image
(which contains the opd section but possibly lacks symbols) and a symbol
image (which probably lacks an opd section but has symbols).
The next patch ("perf symbol: use both runtime and debug images")
adjusts the callsite in dso__load() to take advantage of being able to
pass both runtime & debug images.
Assumptions made here:
- The opd section, if it exists in the runtime image, has headers in
both the runtime image and the debug/syms image.
- The index of the opd section (again, only if it exists in the runtime
image) is the same in both the runtime and debug/symbols image.
Both of these are true on RHEL, but it is unclear how accurate they are
in general (on platforms with function descriptors in opd sections).
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: David Hansen <dave@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Matt Hellsley <matthltc@us.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1344637382-22789-16-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Factors opening of certain sections & tracking certain elf info into an
external structure.
The goal here is to keep multiple elfs (and their looked up
sections/indexes) around during the symbol generation process (in
dso__load()).
We need this to properly resolve symbols on PPC due to the use of
function descriptors & the .opd section (ie: symbols which are functions
don't point to their actual location, they point to their function
descriptor in .opd which contains their actual location.
It would be possible to just keep the (Elf *) around, but then we'd end
up with duplicate code for looking up the same sections and checking for
the existence of an important section wouldn't be as clean (and we need
to keep the Elf stuff confined to symtab-elf.c).
Utilized by the later patch
"perf symbols: Use both runtime and debug images"
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: David Hansen <dave@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Matt Hellsley <matthltc@us.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1344637382-22789-12-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
kallsyms__parse() takes a callback that is called on every discovered
symbol. As /proc/kallsyms does not supply symbol sizes, the callback was
simply called with end=start, faking the symbol size to 1.
All of the callbacks (there are 2) used in calls to kallsyms__parse()
are _only_ used as callbacks for kallsyms__parse().
Given that kallsyms__parse() lacks real information about what
end/length should be, don't make up a length in kallsyms__parse().
Instead have the callbacks handle guessing the length.
Also relocate a comment regarding symbol creation to the callback which
does symbol creation (kallsyms__parse() is not in general used to create
symbols).
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: David Hansen <dave@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Matt Hellsley <matthltc@us.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1344637382-22789-3-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
