The commit dfef99cd0b ("perf probe: Use ref_reloc_sym based address
instead of the symbol name") converts kprobes to use ref_reloc_sym (i.e.
_stext) and offset instead of using symbol's name directly. So on my
system, adding do_fork ends up with like below:
$ sudo perf probe -v --add do_fork%return
probe-definition(0): do_fork%return
symbol:do_fork file:(null) line:0 offset:0 return:1 lazy:(null)
0 arguments
Looking at the vmlinux_path (7 entries long)
Using /lib/modules/3.17.6-1-ARCH/build/vmlinux for symbols
Could not open debuginfo. Try to use symbols.
Opening /sys/kernel/debug/tracing/kprobe_events write=1
Added new event:
Writing event: r:probe/do_fork _stext+456136
Failed to write event: Invalid argument
Error: Failed to add events. Reason: Operation not permitted (Code: -1)
As you can see, the do_fork was translated to _stext+456136. This was
because to support (local) symbols that have same name. But the problem
is that kretprobe requires to be inserted at function start point so it
simply checks whether it's called with offset 0. And if not, it'll
return with -EINVAL. You can see it with dmesg.
$ dmesg | tail -1
[125621.764103] Return probe must be used without offset.
So we need to use the symbol name instead of ref_reloc_sym in case of
return probes.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1421234288-22758-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Removing boilerplate from two places, where one would have to find the
first entry, then iterate using symbol__next_by_name + strcmp to see if
the next member had the same name.
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/n/tip-eh73z8gthv20yowirmx2yk38@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The find_probe_trace_events_from_map() searches matching symbol from a
map (so from a backing dso). For uprobes, it'll create a new map (and
dso) and loads it using a filter. It's a little bit inefficient in that
it'll read out the symbol table everytime but works well anyway.
For kprobes however, it'll reuse existing kernel map which might be
loaded before. In this case map__load() just returns with no result.
It makes kprobes always failed to find symbol even if it exists in the
map (dso).
To fix it, use map__find_symbol_by_name() instead. It'll load a map
with full symbols and sorts them by name. It needs to search sibing
nodes since there can be multiple (local) symbols with same name.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/1421234288-22758-3-git-send-email-namhyung@kernel.org
[ Use symbol__next_by_name ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When it failed to write probe commands to the probe_event file in
debugfs, it needs to propagate the error code properly. Current code
blindly uses the return value of the write(2) so it always uses
-1 (-EPERM) and it might confuse users.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1420886028-15135-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix to fall back to find a probe point in symbols if perf fails to find
it in debuginfo.
This can happen when the target function is an alias of another
function. Such alias doesn't have an entry in debuginfo but in symbols.
David Ahern reported this problem in https://lkml.org/lkml/2014/12/29/355
I ensured the problem and deeper investigation discovers it.
-----
eu-readelf --debug-dump=info /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.19.so | grep \"malloc\" -A6
name (strp) "malloc"
decl_file (data1) 25
decl_line (data2) 466
prototyped (flag_present)
type (ref4) [ 81b5]
declaration (flag_present)
[ 8f58] formal_parameter
--
name (strp) "malloc"
decl_file (data1) 23
decl_line (data2) 466
prototyped (flag_present)
type (ref4) [ 9f4a]
declaration (flag_present)
sibling (ref4) [ bb29]
...
-----
All these entires have no instances (all of them are declarations)
This is why the perf probe failed to find it in debuginfo.
However, there are some malloc instances in symbols.
-----
eu-readelf --symbols /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.19.so | grep malloc$
1181: 0000000000080700 5332 FUNC LOCAL DEFAULT 12 _int_malloc
4537: 00000000000831d0 339 FUNC LOCAL DEFAULT 12 __GI___libc_malloc
5545: 00000000000831d0 339 FUNC LOCAL DEFAULT 12 __malloc
6063: 00000000000831d0 339 FUNC GLOBAL DEFAULT 12 malloc
7302: 00000000000831d0 339 FUNC GLOBAL DEFAULT 12 __libc_malloc
-----
As you an see, malloc and __libc_malloc have same address, and actually
__libc_malloc has an entry in debuginfo. So you can set up a probe on
__libc_malloc.
To fix this problem shortly, perf probe simply falls back to find probe
point(malloc) in symbols if it is not found in debuginfo.
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20141231062747.2087.80961.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add --quiet(-q) option to suppress output result message for --add, and
--del options (Note that --lines/funcs/vars are not affected). This
option is useful if you run the perf probe inside your scripts.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20141027203131.21219.35170.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is a precursor patch to enable long name searching of DSOs using
a rbtree.
In this patch, a new dsos structure is created which contains only a
list head structure for the moment.
The new dsos structure is used, in turn, in the machine structure for
the user_dsos and kernel_dsos fields.
Only the following 3 dsos functions are modified to accept the new dsos
structure parameter instead of list_head:
- dsos__add()
- dsos__find()
- __dsos__findnew()
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hp.com>
Link: http://lkml.kernel.org/r/1412021249-19201-2-git-send-email-Waiman.Long@hp.com
[ Move struct dsos to dso.h to reduce the dso methods depends on machine.h ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Do not access kallsyms to show available variables and show source lines
in user binaries.
This behavior always requires the root privilege when sysctl sets
kernel.kptr_restrict=1, but we don't need it just for analyzing user
binaries.
Without this patch (by normal user, kptr_restrict=1):
----
$ perf probe -x ./perf -V add_cmdname
Failed to init vmlinux path.
Error: Failed to show vars.
$ perf probe -x ./perf -L add_cmdname
Failed to init vmlinux path.
Error: Failed to show lines.
----
With this patch:
----
$ perf probe -x ./perf -V add_cmdname
Available variables at add_cmdname
@<perf_unknown_cmd_config+144>
(No matched variables)
@<list_commands_in_dir+160>
(No matched variables)
@<add_cmdname+0>
char* name
size_t len
struct cmdnames* cmds
$ perf probe -x ./perf -L add_cmdname
<add_cmdname@/home/fedora/ksrc/linux-3/tools/perf/util/help.c:0>
0 void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
1 {
2 struct cmdname *ent = malloc(sizeof(*ent) + len + 1);
4 ent->len = len;
5 memcpy(ent->name, name, len);
6 ent->name[len] = 0;
...
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: david lerner <dlernerdroid@gmail.com>
Cc: linux-perf-user@vger.kernel.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140917084054.3722.73975.stgit@kbuild-f20.novalocal
[ Added missing 'bool user' argument to the !DWARF show_line_range() stub ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To make error messages thread-safe, this replaces strerror with
strerror_r for warnings, and just shows the return value instead of
using strerror for debug messages.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140814022234.3545.22199.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since the strlist__add doesn't involves any IO, the failure reason must
be ENOMEM or EINVAL, moreover this is just a debug message, we don't
need to show the error string.
And also, if get_probe_trace_command_rawlist() returns NULL, it doesn't
mean the rawlist is empty, there is an error. So caller must use
-ENOMEM for the error.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140814022230.3545.99254.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Warn user to rebuild target with debuginfo when the perf probe fails to
find debug information in the target binary.
Without this, perf probe just reports the failure, but it's no hint for
users. This gives more hint for users.
Without this:
$ strip perf
$ ./perf probe -x perf -L argv_split
Failed to open debuginfo file.
Error: Failed to show lines.
With this:
$ strip perf
$ ./perf probe -x perf -L argv_split
The /home/fedora/ksrc/linux-3/tools/perf/perf file has no debug information.
Rebuild with -g, or install an appropriate debuginfo package.
Error: Failed to show lines.
The "rebuild with ..." part changes to "rebuild with CONFIG_DEBUG_INFO"
if the target is the kernel or a kernel module.
Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140815014432.29869.57941.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently vmlinux_path__init() only tries to find vmlinux file from
current directory, /boot and some canonical directories with version
number of the running kernel. This can be a problem when reporting old
data recorded on a kernel version not running currently.
We can use --symfs option for this but it's annoying for user to do it
always. As we already have the info in the perf.data file, it can be
changed to use it for the search automatically.
Before:
$ perf report
...
# Samples: 4K of event 'cpu-clock'
# Event count (approx.): 1067250000
#
# Overhead Command Shared Object Symbol
# ........ .......... ................. ..............................
71.87% swapper [kernel.kallsyms] [k] recover_probed_instruction
After:
# Overhead Command Shared Object Symbol
# ........ .......... ................. ....................
71.87% swapper [kernel.kallsyms] [k] native_safe_halt
This requires to change signature of symbol__init() to receive struct
perf_session_env *.
Reported-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1407825645-24586-14-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Current perf probe --del doesn't work if only CONFIG_UPROBE_EVENTS=y
because it aborts when it fails to open kprobe_events file before
checking uprobe_events file.
This fixes --del option to delete dynamic events if it can open either
kprobe_events or uprobe_events. Only if it failed to open both of them,
it shows an error message and aborts.
Without this patch, if we run perf probe -d on the kernel configured
with CONFIG_KPROBE_EVENTS=n and CONFIG_UPROBE_EVENTS=y,
# perf probe -d \*
kprobe_events file does not exist - please rebuild kernel with CONFIG_KPROBE_EVENTS.
Error: Failed to delete events.
With this patch,
# perf probe -d \*
Removed event: probe_perf:alloc_event
Changes in v2:
- Use strerror_r instead of strerror.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140813161250.26440.24028.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Current perf probe --list doesn't work if only CONFIG_UPROBE_EVENTS=y
because it aborts when it fails to open kprobe_events file before
checking uprobe_events file.
This fixes --list option to show dynamic events if it can open either
kprobe_events or uprobe_events. Only if it failed to open both of them,
it shows an error message and aborts.
Without this patch, if we run perf probe -l on the kernel configured
with CONFIG_KPROBE_EVENTS=n and CONFIG_UPROBE_EVENTS=y,
# perf probe -l
/sys/kernel/debug/tracing/kprobe_events file does not exist - please rebuild ker
Error: Failed to show event list.
With this patch,
# perf probe -l
probe_perf:alloc_event (on alloc_event@lib/traceevent/event-parse.c in /home/fedora/ksrc/linux-3/tools/perf/perf)
Changes in v2:
- Use strerror_r instead of strerror.
Reported-by: Naohiro Aota <naota@elisp.net>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140813161248.26440.84370.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Improve error messages of 'perf probe --line' mode.
Currently 'perf probe' shows the "Debuginfo analysis failed" message with
an error code when the given symbol is not found:
-----
# perf probe -L page_cgroup_init_flatmem
Debuginfo analysis failed. (-2)
Error: Failed to show lines.
-----
But -2 (-ENOENT) means that the given source line or function was not
found. With this patch, 'perf probe' shows the correct error message:
-----
# perf probe -L page_cgroup_init_flatmem
Specified source line is not found.
Error: Failed to show lines.
-----
There is also another debug error code is shown in the same function
after get_real_path(). This removes that too.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@kernel.org>
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/20140606071406.6788.47850.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix an error message when failed to find given address in --vars
mode.
Without this fix, perf probe -V doesn't show the final "Error"
message if it fails to find given source line. Moreover, it
tells it fails to find "variables" instead of the source line.
-----
# perf probe -V foo@bar
Failed to find variables at foo@bar (0)
-----
The result also shows mysterious error code. Actually the error
returns 0 or -ENOENT means that it just fails to find the address
of given source line. (0 means there is no matching address,
and -ENOENT means there is an entry(DIE) but it has no instance,
e.g. an empty inlined function)
This fixes it to show what happened and the final error message
as below.
-----
# perf probe -V foo@bar
Failed to find the address of foo@bar
Error: Failed to show vars.
-----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
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/20140606071359.6788.84716.stgit@kbuild-fedora.novalocal
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>
Allow to add events on the local functions without debuginfo.
(With the debuginfo, we can add events even on inlined functions)
Currently, probing on local functions requires debuginfo to
locate actual address. It is also possible without debuginfo since
we have symbol maps.
Without this change;
----
# ./perf probe -a t_show
Added new event:
probe:t_show (on t_show)
You can now use it in all perf tools, such as:
perf record -e probe:t_show -aR sleep 1
# ./perf probe -x perf -a identity__map_ip
no symbols found in /kbuild/ksrc/linux-3/tools/perf/perf, maybe install a debug package?
Failed to load map.
Error: Failed to add events. (-22)
----
As the above results, perf probe just put one event
on the first found symbol for kprobe event. Moreover,
for uprobe event, perf probe failed to find local
functions.
With this change;
----
# ./perf probe -a t_show
Added new events:
probe:t_show (on t_show)
probe:t_show_1 (on t_show)
probe:t_show_2 (on t_show)
probe:t_show_3 (on t_show)
You can now use it in all perf tools, such as:
perf record -e probe:t_show_3 -aR sleep 1
# ./perf probe -x perf -a identity__map_ip
Added new events:
probe_perf:identity__map_ip (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)
probe_perf:identity__map_ip_1 (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)
probe_perf:identity__map_ip_2 (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)
probe_perf:identity__map_ip_3 (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)
You can now use it in all perf tools, such as:
perf record -e probe_perf:identity__map_ip_3 -aR sleep 1
----
Now we succeed to put events on every given local functions
for both kprobes and uprobes. :)
Note that this also introduces some symbol rbtree
iteration macros; symbols__for_each, dso__for_each_symbol,
and map__for_each_symbol. These are for walking through
the symbol list in a map.
Changes from v2:
- Fix add_exec_to_probe_trace_events() not to convert address
to tp->symbol any more.
- Fix to set kernel probes based on ref_reloc_sym.
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/20140206053225.29635.15026.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Show source-level or symbol-level information for uprobe events.
Without this change;
# ./perf probe -l
probe_perf:dso__load_vmlinux (on 0x000000000006d110 in /kbuild/ksrc/linux-3/tools/perf/perf)
With this change;
# ./perf probe -l
probe_perf:dso__load_vmlinux (on dso__load_vmlinux@util/symbol.c in /kbuild/ksrc/linux-3/tools/perf/perf)
Changes from v2:
- Update according to previous patches.
Changes from v1:
- Rewrite the code based on new series.
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/20140206053223.29635.51280.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Show appropriate symbol for ref_reloc_sym based kprobes instead of
refpoint+offset when perf-probe -l runs without debuginfo.
Without this change:
# ./perf probe -l
probe:t_show (on _stext+889880 with m v)
probe:t_show_1 (on _stext+928568 with m v t)
probe:t_show_2 (on _stext+969512 with m v fmt)
probe:t_show_3 (on _stext+1001416 with m v file)
With this change:
# ./perf probe -l
probe:t_show (on t_show with m v)
probe:t_show_1 (on t_show with m v t)
probe:t_show_2 (on t_show with m v fmt)
probe:t_show_3 (on t_show with m v file)
Changes from v2:
- Check ref_reloc_sym to find correct unrelocated 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/20140206053220.29635.81819.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>
Since several local symbols can have same name (e.g. t_show), we need to
use the relative address from the symbol referred by kmap->ref_reloc_sym
instead of the target symbol name itself.
Because the kernel address space layout randomize (kASLR) changes the
absolute address of kernel symbols, we can't rely on the absolute
address.
Note that this works only with debuginfo.
E.g. without this change;
----
# ./perf probe -a "t_show \$vars"
Added new events:
probe:t_show (on t_show with $vars)
probe:t_show_1 (on t_show with $vars)
probe:t_show_2 (on t_show with $vars)
probe:t_show_3 (on t_show with $vars)
You can now use it in all perf tools, such as:
perf record -e probe:t_show_3 -aR sleep 1
----
OK, we have 4 different t_show()s. All functions have
different arguments as below;
----
# cat /sys/kernel/debug/tracing/kprobe_events
p:probe/t_show t_show m=%di:u64 v=%si:u64
p:probe/t_show_1 t_show m=%di:u64 v=%si:u64 t=%si:u64
p:probe/t_show_2 t_show m=%di:u64 v=%si:u64 fmt=%si:u64
p:probe/t_show_3 t_show m=%di:u64 v=%si:u64 file=%si:u64
----
However, all of them have been put on the *same* address.
----
# cat /sys/kernel/debug/kprobes/list
ffffffff810d9720 k t_show+0x0 [DISABLED]
ffffffff810d9720 k t_show+0x0 [DISABLED]
ffffffff810d9720 k t_show+0x0 [DISABLED]
ffffffff810d9720 k t_show+0x0 [DISABLED]
----
With this change;
----
# ./perf probe -a "t_show \$vars"
Added new events:
probe:t_show (on t_show with $vars)
probe:t_show_1 (on t_show with $vars)
probe:t_show_2 (on t_show with $vars)
probe:t_show_3 (on t_show with $vars)
You can now use it in all perf tools, such as:
perf record -e probe:t_show_3 -aR sleep 1
# cat /sys/kernel/debug/tracing/kprobe_events
p:probe/t_show _stext+889880 m=%di:u64 v=%si:u64
p:probe/t_show_1 _stext+928568 m=%di:u64 v=%si:u64 t=%si:u64
p:probe/t_show_2 _stext+969512 m=%di:u64 v=%si:u64 fmt=%si:u64
p:probe/t_show_3 _stext+1001416 m=%di:u64 v=%si:u64 file=%si:u64
# cat /sys/kernel/debug/kprobes/list
ffffffffb50d95e0 k t_show+0x0 [DISABLED]
ffffffffb50e2d00 k t_show+0x0 [DISABLED]
ffffffffb50f4990 k t_show+0x0 [DISABLED]
ffffffffb50eccf0 k t_show+0x0 [DISABLED]
----
This time, each event is put in different address
correctly.
Note that currently this doesn't support address-based
probe on modules (thus the probes on modules are symbol
based), since it requires relative address probe syntax
for kprobe-tracer, and it isn't implemented yet.
One more note, this allows us to put events on correct
address, but --list option should be updated to show
correct corresponding source code.
Changes from v2:
- Refer kmap->ref_reloc_sym instead of "_stext".
- Refer map->reloc to catch up the kASLR perf fix.
Changes from v1:
- Use _stext relative address instead of actual
absolute address recorded in debuginfo.
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/20140206053216.29635.22584.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Show the name of binary file or modules in which the probes are set with
--list option.
Without this change;
# ./perf probe -m drm drm_av_sync_delay
# ./perf probe -x perf dso__load_vmlinux
# ./perf probe -l
probe:drm_av_sync_delay (on drm_av_sync_delay)
probe_perf:dso__load_vmlinux (on 0x000000000006d110)
With this change;
# ./perf probe -l
probe:drm_av_sync_delay (on drm_av_sync_delay in drm)
probe_perf:dso__load_vmlinux (on 0x000000000006d110 in /kbuild/ksrc/linux-3/tools/perf/perf)
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/20140206053213.29635.69948.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Remove unneeded symbol check for --list option.
This code actually checks whether the given symbol exists in the kernel.
But this is incorrect for online kernel/module and offline module too:
- For online kernel/module, the kprobes itself already
ensured the symbol exist in the kernel.
- For offline module, this code can't access the offlined
modules. Ignore 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/20140206053206.29635.7453.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Some perf-probe commands do symbol_init() but doesn't do exit call.
This fixes that to call symbol_exit() and releases machine if needed.
This also merges init_vmlinux() and init_user_exec() because both of
them are doing similar things. (init_user_exec() just skips init
vmlinux related symbol maps)
Changes from v2:
- Not to set symbol_conf.try_vmlinux_path in init_symbol_maps()
(Thanks to Namhyung Kim!)
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/20140206053204.29635.28334.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix perf-probe not to add offset value twice to uprobe probe address
when post processing.
The tevs[i].point.address struct member is the address of symbol+offset,
but current perf-probe adjusts the point.address by adding the offset.
As a result, the probe address becomes symbol+offset+offset. This may
cause unexpected code corruption. Urgent fix is needed.
Without this fix:
---
# ./perf probe -x ./perf dso__load_vmlinux+4
# ./perf probe -l
probe_perf:dso__load_vmlinux (on 0x000000000006d2b8)
# nm ./perf.orig | grep dso__load_vmlinux\$
000000000046d0a0 T dso__load_vmlinux
---
You can see the given offset is 3 but the actual probed address is
dso__load_vmlinux+8.
With this fix:
---
# ./perf probe -x ./perf dso__load_vmlinux+4
# ./perf probe -l
probe_perf:dso__load_vmlinux (on 0x000000000006d2b4)
---
Now the problem is fixed.
Note: This bug is introduced by
commit fb7345bbf7
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: David Ahern <dsahern@gmail.com>
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/20140205051858.6519.27314.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Remove duplicated elf_section_by_name() functions from unwind.c and
probe-event.c and use one exported elf_section_by_name() instance
defined in symbol-elf.c.
Note that this also moves get_text_start_address() to merge
HAVE_DWARF_SUPPORT defined area.
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Cc: David Ahern <dsahern@gmail.com>
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: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140116093949.24403.38093.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
On a freshly installed system, after libelf-dev is installed we get:
CC /tmp/build/perf/util/probe-event.o
util/probe-event.c: In function ‘try_to_find_probe_trace_events’:
util/probe-event.c:753:46: error: unused parameter ‘target’ [-Werror=unused-parameter]
int max_tevs __maybe_unused, const char *target)
^
CC /tmp/build/perf/util/cgroup.o
util/probe-event.c: At top level:
util/probe-event.c:193:12: error: ‘get_text_start_address’ defined but not used [-Werror=unused-function]
static int get_text_start_address(const char *exec, unsigned long *address)
^
cc1: all warnings being treated as errors
make[1]: *** [/tmp/build/perf/util/probe-event.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [install] Error 2
Fix it by enclosing functions only used when those libraries are installed
under the suitable preprocessor define and using __maybe_unused to a function
that is only built when DWARF support is disabled.
Problem introduced in this changeset:
commit fb7345bbf7
Author: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Date: Thu Dec 26 05:41:53 2013 +0000
perf probe: Support basic dwarf-based operations on uprobe events
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: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
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-73kc2fopt81517hrdgdra18o@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Several areas already used this technique, so do some audit to
consistently use it elsewhere.
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: Namhyung Kim <namhyung@kernel.org>
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-9sbere0kkplwe45ak6rk4a1f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For the frequent idiom of:
free(ptr);
ptr = NULL;
Make it expect a pointer to the pointer being freed, so that it becomes
clear at first sight that the variable being freed is being modified.
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: Namhyung Kim <namhyung@kernel.org>
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-pfw02ezuab37kha18wlut7ir@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Its perfectly fine to call free(NULL), so no need to clutter the source
code with all those superfluous testing.
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: Namhyung Kim <namhyung@kernel.org>
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-uux5wpvevlerd42gqer13e7n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Support basic dwarf(debuginfo) based operations for uprobe events. With
this change, perf probe can analyze debuginfo of user application binary
to set up new uprobe event.
This allows perf-probe --add(with local variables, line numbers) and
--line works with -x option. (Actually, --vars has already accepted -x
option)
For example, the following command shows the probe-able lines of a given
user space function. Something that so far was only available in the
'perf probe' tool for kernel space functions:
# ./perf probe -x perf --line map__load
<map__load@/home/fedora/ksrc/linux-2.6/tools/perf/util/map.c:0>
0 int map__load(struct map *map, symbol_filter_t filter)
1 {
2 const char *name = map->dso->long_name;
int nr;
5 if (dso__loaded(map->dso, map->type))
6 return 0;
8 nr = dso__load(map->dso, map, filter);
9 if (nr < 0) {
10 if (map->dso->has_build_id) {
And this shows the available variables at the given line of the
function.
# ./perf probe -x perf --vars map__load:8
Available variables at map__load:8
@<map__load+96>
char* name
struct map* map
symbol_filter_t filter
@<map__find_symbol+112>
char* name
symbol_filter_t filter
@<map__find_symbol_by_name+136>
char* name
symbol_filter_t filter
@<map_groups__find_symbol_by_name+176>
char* name
struct map* map
symbol_filter_t filter
And lastly, we can now define probe(s) with all available
variables on the given line:
# ./perf probe -x perf --add 'map__load:8 $vars'
Added new events:
probe_perf:map__load (on map__load:8 with $vars)
probe_perf:map__load_1 (on map__load:8 with $vars)
probe_perf:map__load_2 (on map__load:8 with $vars)
probe_perf:map__load_3 (on map__load:8 with $vars)
You can now use it in all perf tools, such as:
perf record -e probe_perf:map__load_3 -aR sleep 1
Changes from previous version:
- Add examples in the patch description.
- Use .text section start address and dwarf symbol address
for calculating the offset of given symbol, instead of
searching the symbol in symtab again.
With this change, we can safely handle multiple local
function instances (e.g. scnprintf in perf).
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@kernel.org>
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: systemtap@sourceware.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20131226054152.22364.47021.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Expand given path to absolute path in the option parser, except for a
module name.
Since realpath at later stage in processing several probe point, can be
called several times (even if currently doesn't, it can happen when we
expands the feature), it is waste of the performance.
Processing it once at the early stage can avoid that.
Changes from previous one:
- Fix not to print null string.
- Allocate memory for given path/module name everytime.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: systemtap@sourceware.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20131226054150.22364.12187.stgit@kbuild-fedora.novalocal
[ Clarified the pr_warning message as per David Ahern's suggestion ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Move debugfs.* to api/fs/. We have a common tools/lib/api/ place where
the Makefile lives and then we place the headers in subdirs.
For example, all the fs-related stuff goes to tools/lib/api/fs/ from
which we get libapikfs.a (acme got almost the naming he wanted :-)) and
we link it into the tools which need it - in this case perf and
tools/vm/page-types.
acme:
"Looking at the implementation, I think some tools can even link
directly to the .o files, avoiding the .a file altogether.
But that is just an optimization/finer granularity tools/lib/
cherrypicking that toolers can make use of."
Fixup documentation cleaning target while at it.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
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: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <rric@kernel.org>
Cc: Stanislav Fomichev <stfomichev@yandex-team.ru>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1386605664-24041-2-git-send-email-bp@alien8.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is a preparatory patch to do with dso__set_long_name what was done
with the short name variant.
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: Namhyung Kim <namhyung@kernel.org>
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-mb7eqhkyejq1qcf3p22wz2x7@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>
This introduces the tools/lib/lk library, that will gradually have the
routines that now are used in tools/perf/ and other tools and that can
be shared.
Start by carving out debugfs routines for general use.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1361374353-30385-5-git-send-email-bp@alien8.de
[ committer note: Add tools/lib/lk/ to perf's MANIFEST so that its tarballs continue to build ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf uses sscanf extension %as to read and allocate a string in the same
step. This is a non-standard extension only present in new versions of
glibc.
Replacing the use of sscanf and %as with strtok_r calls in order to
parse a given string into its components. This is needed in Android
since bionic does not support
%as extension for sscanf.
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1348173470-4936-1-git-send-email-irina.tirdea@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf defines both __used and __unused variables to use for marking
unused variables. The variable __used is defined to
__attribute__((__unused__)), which contradicts the kernel definition to
__attribute__((__used__)) for new gcc versions. On Android, __used is
also defined in system headers and this leads to warnings like: warning:
'__used__' attribute ignored
__unused is not defined in the kernel and is not a standard definition.
If __unused is included everywhere instead of __used, this leads to
conflicts with glibc headers, since glibc has a variables with this name
in its headers.
The best approach is to use __maybe_unused, the definition used in the
kernel for __attribute__((unused)). In this way there is only one
definition in perf sources (instead of 2 definitions that point to the
same thing: __used and __unused) and it works on both Linux and Android.
This patch simply replaces all instances of __used and __unused with
__maybe_unused.
Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1347315303-29906-7-git-send-email-irina.tirdea@intel.com
[ committer note: fixed up conflict with a116e05 in builtin-sched.c ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The basename function may modify the string passed to it, so the string
should not be marked const.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Irina Tirdea <irina.tirdea@gmail.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1347116812-93646-3-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
- Enhances perf to probe user space executables and libraries.
- Enhances -F/--funcs option of "perf probe" to list possible probe points in
an executable file or library.
- Documents userspace probing support in perf.
[ Probing a function in the executable using function name ]
perf probe -x /bin/zsh zfree
[ Probing a library function using function name ]
perf probe -x /lib64/libc.so.6 malloc
[ list probe-able functions in an executable ]
perf probe -F -x /bin/zsh
[ list probe-able functions in an library]
perf probe -F -x /lib/libc.so.6
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Anton Arapov <anton@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120416120909.30661.99781.sendpatchset@srdronam.in.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The 'perf probe' command allows kprobe to be inserted at any offset from
a function start, which results in adding kprobes to unintended
location. (example: perf probe do_fork+10000 is allowed even though
size of do_fork is ~904).
My previous patch https://lkml.org/lkml/2012/2/24/42 addressed the case
where DWARF info was available for the kernel. This patch fixes the
case where perf probe is used on a kernel without debuginfo available.
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/4F4C544D.1010909@linux.vnet.ibm.com
Signed-off-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
