Support probing on offline cross-architecture binary by adding getting
the target machine arch from ELF and choose correct register string for
the machine.
Here is an example:
-----
$ perf probe --vmlinux=./vmlinux-arm --definition 'do_sys_open $params'
p:probe/do_sys_open do_sys_open+0 dfd=%r5:s32 filename=%r1:u32 flags=%r6:s32 mode=%r3:u16
-----
Here, we can get probe/do_sys_open from above and append it to to the target
machine's tracing/kprobe_events file in the tracefs mountput, usually
/sys/kernel/debug/tracing/kprobe_events (or /sys/kernel/tracing/kprobe_events).
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214229717.23638.6440579792548044658.stgit@devbox
[ Add definition for EM_AARCH64 to fix the build on at least centos 6, debian 7 & ubuntu 12.04.5 ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.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-w246stf7ponfamclsai6b9zo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
'perf probe' through debuginfo__find_probes() in util/probe-finder.c
checks for the functions' frame descriptions in either .eh_frame section
of an ELF or the .debug_frame.
The check is based on whether either one of these sections is present.
Depending on distro, toolchain defaults, architetcutre, build flags,
etc., CFI might be found in either .eh_frame and/or .debug_frame.
Sometimes, it may happen that, .eh_frame, even if present, may not be
complete and may miss some descriptions.
Therefore, to be sure, to find the CFI covering an address we will
always have to investigate both if available.
For e.g., in powerpc, this may happen:
$ gcc -g bin.c -o bin
$ objdump --dwarf ./bin
<1><145>: Abbrev Number: 7 (DW_TAG_subprogram)
<146> DW_AT_external : 1
<146> DW_AT_name : (indirect string, offset: 0x9e): main
<14a> DW_AT_decl_file : 1
<14b> DW_AT_decl_line : 39
<14c> DW_AT_prototyped : 1
<14c> DW_AT_type : <0x57>
<150> DW_AT_low_pc : 0x100007b8
If the .eh_frame and .debug_frame are checked for the same binary, we
will find that, .eh_frame (although present) doesn't contain a
description for "main" function.
But, .debug_frame has a description:
000000d8 00000024 00000000 FDE cie=00000000 pc=100007b8..10000838
DW_CFA_advance_loc: 16 to 100007c8
DW_CFA_def_cfa_offset: 144
DW_CFA_offset_extended_sf: r65 at cfa+16
...
Due to this (since, perf checks whether .eh_frame is present and goes on
searching for that address inside that frame), perf is unable to process
the probes:
# perf probe -x ./bin main
Failed to get call frame on 0x100007b8
Error: Failed to add events.
To avoid this issue, we need to check both the sections (.eh_frame and
.debug_frame), which is done in this patch.
Note that, we can always force everything into both .eh_frame and
.debug_frame by:
$ gcc bin.c -fasynchronous-unwind-tables -fno-dwarf2-cfi-asm -g -o bin
Signed-off-by: Hemant Kumar <hemant@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1454426806-13974-1-git-send-email-hemant@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce probe_conf global configuration parameters for probe-event and
probe-finder, and removes related parameters from APIs.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.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/20150508010330.24812.21095.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If we use lazy matching, it failed to open a souce file if perf command
is invoked outside of compilation directory:
$ perf probe -a '__schedule;clear_*'
Failed to open kernel/sched/core.c: No such file or directory
Error: Failed to add events. (-2)
OTOH, other commands like "probe -L" can solve the souce directory by
themselves. Let's make it possible for lazy matching too!
Signed-off-by: Naohiro Aota <naota@elisp.net>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
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/1426223923-1493-1-git-send-email-naota@elisp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Support distro-style debuginfo supported by dso for setting uprobes.
Note that this tries to find a debuginfo file based on the real path of
the target binary. If the debuginfo is not correctly installed on the
system, this can not find it.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.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/20140206053227.29635.54434.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Find the given address from offline dwarfs instead of online kernel
dwarfs.
On the KASLR enabled kernel, the kernel text section is loaded with
random offset, and the debuginfo__new_online_kernel can't handle it. So
let's move to the offline dwarf loader instead of using the online dwarf
loader.
As a result, since we don't need debuginfo__new_online_kernel any more,
this also removes the functions related to that.
Without this change;
# ./perf probe -l
probe:t_show (on _stext+901288 with m v)
probe:t_show_1 (on _stext+939624 with m v t)
probe:t_show_2 (on _stext+980296 with m v fmt)
probe:t_show_3 (on _stext+1014392 with m v file)
With this change;
# ./perf probe -l
probe:t_show (on t_show@linux-3/kernel/trace/ftrace.c with m v)
probe:t_show_1 (on t_show@linux-3/kernel/trace/trace.c with m v t)
probe:t_show_2 (on t_show@kernel/trace/trace_printk.c with m v fmt)
probe:t_show_3 (on t_show@kernel/trace/trace_events.c with m v file)
Changes from v2:
- Instead of retrying, directly opens offline dwarf.
- Remove debuginfo__new_online_kernel and related functions.
- Refer map->reloc to get the correct address of a symbol.
- Add a special case for handling ref_reloc_sym based address.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.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/20140206053218.29635.74821.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
They convey no information, perhaps I was bitten by some snake at some
point, complete the detox by naming the last of those arguments more
sensibly.
Cc: Adrian Hunter <adrian.hunter@intel.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: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-u1r0dnjoro08dgztiy2g3t2q@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Support "$vars" meta argument syntax for tracing all local variables at
probe point.
Now you can trace all available local variables (including function
parameters) at the probe point by passing $vars.
# perf probe --add foo $vars
This automatically finds all local variables at foo() and adds it as
probe arguments.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20131011071023.15557.51770.stgit@udc4-manage.rcp.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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 <acme@ghostprotocols.net>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20130925131616.31632.46658.stgit@udc4-manage.rcp.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
No need for multiple definitions for STR() and die(), also use SuSv2's
PATH_MAX instead of adding MAX_PATH.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
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-qpujjkw7u0bf0tr4wt55cr9y@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
Introduce debuginfo to encapsulate dwarf information.
This new object allows us to reuse and expand debuginfo easily.
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/20110627072739.6528.12438.stgit@fedora15
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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>
v3 -> v2:
- Make pubname_search_cb more generic
- Add fastpath to find_probes also
v2 -> v1:
- Don't compare file names with cu_find_realpath(...), instead, compare
them with the name returned by dwarf_decl_file(sp_die)
The vmlinux file may have thousands of CUs.
We can lookup function name from .debug_pubnames section
to avoid the slow loop on CUs.
1. Improvement data for find_line_range
./perf stat -e cycles -r 10 -- ./perf probe -k /home/mlin/vmlinux \
-s /home/mlin/linux-2.6 \
--line csum_partial_copy_to_user > tmp.log
before patch applied
=====================
847,988,276 cycles
0.355075856 seconds time elapsed
after patch applied
=====================
206,102,622 cycles
0.086883555 seconds time elapsed
2. Improvement data for find_probes
./perf stat -e cycles -r 10 -- ./perf probe -k /home/mlin/vmlinux \
-s /home/mlin/linux-2.6 \
--vars csum_partial_copy_to_user > tmp.log
before patch applied
=====================
848,490,844 cycles
0.355307901 seconds time elapsed
after patch applied
=====================
205,684,469 cycles
0.086694010 seconds time elapsed
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
LKML-Reference: <1301041668.14111.52.camel@minggr.sh.intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This change removes the use of hardcoded absolute "/usr/include/elfutils" paths
from the perf build. The problem with hardcoded paths is that it prevents them
from being overridden by $prefix or by -I in CFLAGS (e.g., for cross-compiling
purposes).
Instead, just include the "elfutils/" subdirectory as a relative path when
files are needed from that directory.
Tested by building perf:
- Cross-compiled for ARM on x86_64
- Built natively on x86_64
- Built on x86_64 with /usr/include/elfutils moved to another location
and manually included in CFLAGS
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1289945793-31441-1-git-send-email-rmorell@nvidia.com>
Signed-off-by: Robert Morell <rmorell@nvidia.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add basic module probe support on perf probe. This introduces "--module
<MODNAME>" option to perf probe for putting probes and showing lines and
variables in the given module.
Currently, this supports only probing on running modules. Supporting off-line
module probing is the next step.
e.g.)
[show lines]
# ./perf probe --module drm -L drm_vblank_info
<drm_vblank_info:0>
0 int drm_vblank_info(struct seq_file *m, void *data)
1 {
struct drm_info_node *node = (struct drm_info_node *) m->private
3 struct drm_device *dev = node->minor->dev;
...
[show vars]
# ./perf probe --module drm -V drm_vblank_info:3
Available variables at drm_vblank_info:3
@<drm_vblank_info+20>
(unknown_type) data
struct drm_info_node* node
struct seq_file* m
[put a probe]
# ./perf probe --module drm drm_vblank_info:3 node m
Add new event:
probe:drm_vblank_info (on drm_vblank_info:3 with node m)
You can now use it on all perf tools, such as:
perf record -e probe:drm_vblank_info -aR sleep 1
[list probes]
# ./perf probe -l
probe:drm_vblank_info (on drm_vblank_info:3@drivers/gpu/drm/drm_info.c with ...
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101021101341.3542.71638.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add --externs for allowing --vars to show accessible global (externally
defined) variables from a given probe point too.
This will give you a hint which globals can be accessible from the probe point.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101021101335.3542.31003.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add -V (--vars) option for listing accessible local variables at given probe
point. This will help finding which local variables are available for event
arguments.
e.g.)
# perf probe -V call_timer_fn:23
Available variables at call_timer_fn:23
@<run_timer_softirq+345>
function_type* fn
int preempt_count
long unsigned int data
struct list_head work_list
struct list_head* head
struct timer_list* timer
struct tvec_base* base
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101021101323.3542.40282.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As a precursor for perf to support uprobes, rename fields/functions
that had kprobe in their name but can be shared across perf-kprobes
and perf-uprobes to probe.
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Naren A Devaiah <naren.devaiah@in.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20100729141351.GG21723@linux.vnet.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Check elfutils version, and if it is old don't compile CFI analysis code. This
allows to compile perf with old elfutils.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Tested-by: Stephane Eranian <eranian@google.com>
Reported-by: Robert Richter <robert.richter@amd.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20100510171207.26029.97604.stgit@localhost6.localdomain6>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add --max-probes option to change the maximum limit of
findable probe points per event, since inlined function can be
expanded into thousands of probe points. Default value is 128.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20100421195640.24664.62984.stgit@localhost6.localdomain6>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When building kernel without CONFIG_FRAME_POINTER, gcc uses
CFA (canonical frame address) for frame base. With this patch,
perf probe just gets CFI (call frame information) from debuginfo
and search corresponding CFA from the CFI. IOW, this allows
perf probe works correctly on the kernel without CONFIG_FRAME_POINTER.
<Before>
./perf probe -fn sched_slice:12 lw.weight
Fatal: DW_OP 156 is not supported.
(^^^ DW_OP_call_frame_cfa)
<After>
./perf probe -fn sched_slice:12 lw.weight
Add new event:
probe:sched_slice (on sched_slice:12 with weight=lw.weight)
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171728.3790.98217.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cleanup debuginfo related code to eliminate fragile code which
pointed by Ingo (Thanks!).
1) Invert logic of NO_DWARF_SUPPORT to DWARF_SUPPORT.
2) For removing assymetric/local variable ifdefs, introduce
more helper functions.
3) Change options order to reduce the number of ifdefs.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1269274229-20442-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Improve --list to show current exist probes with line number and
file name. This enables user easily to check which line is
already probed.
for example:
./perf probe --list
probe:vfs_read (on vfs_read:8@linux-2.6-tip/fs/read_write.c)
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100316220619.32050.48702.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Introduce kprobe_trace_event and perf_probe_event and replace
old probe_point structure with it. probe_point structure is
not enough flexible nor extensible. New data structures
will help implementing further features.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100316220612.32050.33806.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use original address for looking up the location of variables
for dwarf_getlocation_addr() instead of CU-based address.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20100315170235.31852.91195.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add lazy line matching support for specifying new probes.
This also changes the syntax of perf probe a bit. Now
perf probe accepts one of below probe event definitions.
1) Define event based on function name
[EVENT=]FUNC[@SRC][:RLN|+OFF|%return|;PTN] [ARG ...]
2) Define event based on source file with line number
[EVENT=]SRC:ALN [ARG ...]
3) Define event based on source file with lazy pattern
[EVENT=]SRC;PTN [ARG ...]
- New lazy matching pattern(PTN) follows ';' (semicolon). And it
must be put the end of the definition.
- So, @SRC is no longer the part which must be put at the end
of the definition.
Note that ';' (semicolon) can be interpreted as the end of
a command by the shell. This means that you need to quote it.
(anyway you will need to quote the lazy pattern itself too,
because it may contains other sensitive characters, like
'[',']' etc.).
Lazy matching
-------------
The lazy line matching is similar to glob matching except
ignoring spaces in both of pattern and target.
e.g.
'a=*' can matches 'a=b', 'a = b', 'a == b' and so on.
This provides some sort of flexibility and robustness to
probe point definitions against minor code changes.
(for example, actual 10th line of schedule() can be changed
easily by modifying schedule(), but the same line matching
'rq=cpu_rq*' may still exist.)
Changes in v3:
- Cast Dwarf_Addr to uintmax_t for printf-formats.
Changes in v2:
- Cast Dwarf_Addr to unsigned long long for printf-formats.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20100225133611.6725.45078.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Check (inlined) function address range strictly for
improving output of probe-able lines of inline functions.
Without this change, perf probe --line <function> sometimes
showed other inline function bodies too, because it didn't
filter out inlined functions.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20100225133557.6725.20697.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use libdw callback functions aggressively, and remove
local tree-search API. This change simplifies the code.
Changes in v3:
- Cast Dwarf_Addr to uintmax_t for printf-formats.
Changes in v2:
- Cast Dwarf_Addr to unsigned long long for printf-formats.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20100225133549.6725.81499.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Newer gcc introduces newer & richer debuginfo, and only libdw
in elfutils project can support it. So perf probe moves onto
elfutils-libdw from libdwarf.
Changes in v3:
- Cast Dwarf_Addr/Dwarf_Word to uintmax_t for printf-formats.
- Recover a sign-prefix which was removed in v2 by mistake.
Changes in v2:
- Fix a type-casting bug in Makefile.
- Cast Dwarf_Addr/Dwarf_Word to unsigned long long for printf-formats.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20100225133542.6725.34724.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add --line option to support showing probable source-code lines.
perf probe --line SRC:LN[-LN|+NUM]
or
perf probe --line FUNC[:LN[-LN|+NUM]]
This option shows source-code with line number if the line can
be probed. Lines without line number (and blue color) means that
the line can not be probed, because debuginfo doesn't have the
information of those lines.
The argument specifies the range of lines, "source.c:100-120"
shows lines between 100th to l20th in source.c file. And
"func:10+20" shows 20 lines from 10th line of func function.
e.g.
# ./perf probe --line kernel/sched.c:1080
<kernel/sched.c:1080>
*
* called with rq->lock held and irqs disabled
*/
static void hrtick_start(struct rq *rq, u64 delay)
{
struct hrtimer *timer = &rq->hrtick_timer;
1086 ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
hrtimer_set_expires(timer, time);
1090 if (rq == this_rq()) {
1091 hrtimer_restart(timer);
1092 } else if (!rq->hrtick_csd_pending) {
1093 __smp_call_function_single(cpu_of(rq), &rq->hrtick_csd,
1094 rq->hrtick_csd_pending = 1;
If you specifying function name, this shows function-relative
line number.
# ./perf probe --line schedule
<schedule:0>
asmlinkage void __sched schedule(void)
1 {
struct task_struct *prev, *next;
unsigned long *switch_count;
struct rq *rq;
int cpu;
need_resched:
preempt_disable();
9 cpu = smp_processor_id();
10 rq = cpu_rq(cpu);
11 rcu_sched_qs(cpu);
12 prev = rq->curr;
13 switch_count = &prev->nivcsw;
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <20100106144534.27218.77939.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
And this resulted in the need for adding some missing includes
in some places that were getting the definitions needed out of
sheer luck.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1261957026-15580-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix libdwarf include path to fit debian-like systems too.
Borislav Petkov reported:
> even after installing libdwarf-dev on my debian box here,
> make in tools/perf/ still complains that it cannot find libdwarf:
>
> Makefile:491: No libdwarf.h found or old libdwarf.h found, disables dwarf
> support. Please install libdwarf-dev/libdwarf-devel >= 20081231
>
> The problem is that the include path on debian is not
> /usr/include/libdwarf/ but simply /usr/include because the debian
> package libdwarf-dev puts the headers straight into
> /usr/include.
This patch adds -I/usr/include/libdwarf to BASIC_CFLAGS
and fix probe-finder.h to include just libdwarf.h/dwarf.h.
This patch also adds a workaround for the undefined _MIPS_SZLONG
bug in libdwarf.h.
Reported-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Gabor Gombas <gombasg@sztaki.hu>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091216221618.13816.83296.stgit@dhcp-100-2-132.bos.redhat.com>
[ v2: small stylistic fixlets to probe-finder.h ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Support event name syntax for --add option. This allows
users to specify event name for each new event.
The --add syntax is:
perf probe --add '[EVENT=]SRC:LINE ARGS'
or
perf probe --add '[EVENT=]FUNC[+OFFS|%return|:RLN][@SRC] ARGS'
e.g.
./perf probe --add myprobe1=schedule
Note: currently group name is not supported yet, because it
can cause name-space confliction with other tracepoint/
hw-breakpoint events.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091215153218.17436.84675.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add function-entry relative line number specifying support to
perf-probe. This allows users to define probes by line number
from entry of the function.
e.g.
perf probe schedule:16
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
LKML-Reference: <20091027204319.30545.30678.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This changes probe point syntax of perf-probe as below
<SRC>[:ABS_LN] [ARGS]
or
<FUNC>[+OFFS|%return][@SRC] [ARGS]
And event name and event group name are automatically
generated based on probe-symbol and offset as below.
perfprobes/SYMBOL_OFFSET[_NUM]
Where SYMBOL is the probing symbol and OFFSET is
the byte offset from the symbol.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
LKML-Reference: <20091027204310.30545.84984.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Enables 'perf probe' even if libdwarf is not installed. If libdwarf is
not found, 'perf probe' just disables dwarf support. Users can use
'perf probe' to set up new events by using kprobe_events format.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
LKML-Reference: <20091007222830.1684.25665.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Add perf probe subcommand that implements a kprobe-event setup helper
to the perf command.
This allows user to define kprobe events using C expressions (C line
numbers, C function names, and C local variables).
Usage
-----
perf probe [<options>] -P 'PROBEDEF' [-P 'PROBEDEF' ...]
-k, --vmlinux <file> vmlinux/module pathname
-P, --probe <p|r:[GRP/]NAME FUNC[+OFFS][@SRC]|@SRC:LINE [ARG ...]>
probe point definition, where
p: kprobe probe
r: kretprobe probe
GRP: Group name (optional)
NAME: Event name
FUNC: Function name
OFFS: Offset from function entry (in byte)
SRC: Source code path
LINE: Line number
ARG: Probe argument (local variable name or
kprobe-tracer argument format is supported.)
Changes in v4:
- Add _GNU_SOURCE macro for strndup().
Changes in v3:
- Remove -r option because perf always be used for online kernel.
- Check malloc/calloc results.
Changes in v2:
- Check synthesized string length.
- Rename perf kprobe to perf probe.
- Use spaces for separator and update usage comment.
- Check error paths in parse_probepoint().
- Check optimized-out variables.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
LKML-Reference: <20091008211737.29299.14784.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>