Pull trivial tree from Jiri Kosina:
"Usual trivial tree updates. Nothing outstanding -- mostly printk()
and comment fixes and unused identifier removals"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
goldfish: goldfish_tty_probe() is not using 'i' any more
powerpc: Fix comment in smu.h
qla2xxx: Fix printks in ql_log message
lib: correct link to the original source for div64_u64
si2168, tda10071, m88ds3103: Fix firmware wording
usb: storage: Fix printk in isd200_log_config()
qla2xxx: Fix printk in qla25xx_setup_mode
init/main: fix reset_device comment
ipwireless: missing assignment
goldfish: remove unreachable line of code
coredump: Fix do_coredump() comment
stacktrace.h: remove duplicate declaration task_struct
smpboot.h: Remove unused function prototype
treewide: Fix typo in printk messages
treewide: Fix typo in printk messages
mod_devicetable: fix comment for match_flags
The first argument passed to find_probe_point_lazy() should be CU die,
which will be passed to die_walk_lines() when lazy_line matches.
Currently, when we probe with lazy_line pattern to file without function
name, NULL pointer is passed and causes a segment fault.
Can be reproduced as following:
$ perf probe -k vmlinux --add='fs/super.c;s->s_count=1;'
[ 1958.984658] perf[1020]: segfault at 10 ip 00007fc6e10d8c71 sp
00007ffcbfaaf900 error 4 in libdw-0.161.so[7fc6e10ce000+34000]
Segmentation fault
After this patch:
$ perf probe -k vmlinux --add='fs/super.c;s->s_count=1;'
Added new event:
probe:_stext (on @fs/super.c)
You can now use it in all perf tools, such as:
perf record -e probe:_stext -aR sleep 1
Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1428925290-5623-3-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix 'perf probe' to track down unnamed union/structure members.
perf probe did not track down the tree of unnamed union/structure
members, since it just failed to find given "name" in a parent
structure/union. To solve this issue, I've introduced 2 changes.
- Fix die_find_member() to track down the type-DIE if it is
unnamed, and if it contains the specified member, returns the
unnamed member.
(note that we don't return found member, since unnamed member
has the offset in the parent structure)
- Fix convert_variable_fields() to track down the unnamed union/
structure (one-by-one).
With this patch, perf probe can access unnamed fields:
-----
#./perf probe -nfx ./perf lock__delete ops 'locked_ops=ops->locked.ops'
Added new event:
probe_perf:lock__delete (on lock__delete in /home/mhiramat/ksrc/linux-3/tools/perf/perf with ops locked_ops=ops->locked.ops)
You can now use it in all perf tools, such as:
perf record -e probe_perf:lock__delete -aR sleep 1
-----
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Report-Link: https://lkml.org/lkml/2015/3/5/431
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.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/20150402073312.14482.37942.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Remove bias offset to find probe point by address.
Without this patch, probe points on kernel and executables are shown
correctly, but do not work with libraries:
# ./perf probe -l
probe:do_fork (on do_fork@kernel/fork.c)
probe_libc:malloc (on malloc in /usr/lib64/libc-2.17.so)
probe_perf:strlist__new (on strlist__new@util/strlist.c in /home/mhiramat/ksrc/linux-3/tools/perf/perf)
Removing bias allows it to show it as real place:
# ./perf probe -l
probe:do_fork (on do_fork@kernel/fork.c)
probe_libc:malloc (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17.so)
probe_perf:strlist__new (on strlist__new@util/strlist.c in /home/mhiramat/ksrc/linux-3/tools/perf/perf)
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150302124946.9191.64085.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix to handle optimized no-inline functions which have only function
definition but no actual instance at that point.
To fix this problem, we need to find actual instance of the function.
Without this patch:
----
# perf probe -a __up
Failed to get entry address of __up.
Error: Failed to add events.
# perf probe -L __up
Specified source line is not found.
Error: Failed to show lines.
----
With this patch:
----
# perf probe -a __up
Added new event:
probe:__up (on __up)
You can now use it in all perf tools, such as:
perf record -e probe:__up -aR sleep 1
# perf probe -L __up
<__up@/home/fedora/ksrc/linux-3/kernel/locking/semaphore.c:0>
0 static noinline void __sched __up(struct semaphore *sem)
{
struct semaphore_waiter *waiter = list_first_entry(&sem->wait_
struct semaphore_waite
4 list_del(&waiter->list);
5 waiter->up = true;
6 wake_up_process(waiter->task);
7 }
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150130093744.30575.43290.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
David reported that perf can segfault when adding an uprobe event like
this:
$ perf probe -x /lib64/libc-2.14.90.so -a 'malloc size=%di'
(gdb) bt
#0 parse_eh_frame_hdr (hdr=0x0, hdr_size=2596, hdr_vaddr=71788,
ehdr=0x7fffffffd390, eh_frame_vaddr=
0x7fffffffd378, table_entries=0x8808d8, table_encoding=0x8808e0 "") at
dwarf_getcfi_elf.c:79
#1 0x000000385f81615a in getcfi_scn_eh_frame (hdr_vaddr=71788,
hdr_scn=0x8839b0, shdr=0x7fffffffd2f0, scn=<optimized out>,
ehdr=0x7fffffffd390, elf=0x882b30) at dwarf_getcfi_elf.c:231
#2 getcfi_shdr (ehdr=0x7fffffffd390, elf=0x882b30) at dwarf_getcfi_elf.c:283
#3 dwarf_getcfi_elf (elf=0x882b30) at dwarf_getcfi_elf.c:309
#4 0x00000000004d5bac in debuginfo__find_probes (pf=0x7fffffffd4f0,
dbg=Unhandled dwarf expression opcode 0xfa) at util/probe-finder.c:993
#5 0x00000000004d634a in debuginfo__find_trace_events (dbg=0x880840,
pev=<optimized out>, tevs=0x880f88, max_tevs=<optimized out>) at
util/probe-finder.c:1200
#6 0x00000000004aed6b in try_to_find_probe_trace_events (target=0x881b20
"/lib64/libpthread-2.14.90.so",
max_tevs=128, tevs=0x880f88, pev=0x859b30) at util/probe-event.c:482
#7 convert_to_probe_trace_events (target=0x881b20
"/lib64/libpthread-2.14.90.so", max_tevs=128, tevs=0x880f88,
pev=0x859b30) at util/probe-event.c:2356
#8 add_perf_probe_events (pevs=<optimized out>, npevs=1, max_tevs=128,
target=0x881b20 "/lib64/libpthread-2.14.90.so", force_add=false) at
util/probe-event.c:2391
#9 0x000000000044014f in __cmd_probe (argc=<optimized out>,
argv=0x7fffffffe2f0, prefix=Unhandled dwarf expression opcode 0xfa) at
at builtin-probe.c:488
#10 0x0000000000440313 in cmd_probe (argc=5, argv=0x7fffffffe2f0,
prefix=<optimized out>) at builtin-probe.c:506
#11 0x000000000041d133 in run_builtin (p=0x805680, argc=5,
argv=0x7fffffffe2f0) at perf.c:341
#12 0x000000000041c8b2 in handle_internal_command (argv=<optimized out>,
argc=<optimized out>) at perf.c:400
#13 run_argv (argv=<optimized out>, argcp=<optimized out>) at perf.c:444
#14 main (argc=5, argv=0x7fffffffe2f0) at perf.c:559
And I found a related commit (5704c8c4fa71 "getcfi_scn_eh_frame: Don't
crash and burn when .eh_frame bits aren't there.") in elfutils that can
lead to a unexpected crash like this. To safely use the function, it
needs to check the .eh_frame section is a PROGBITS type.
Reported-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/20141230090533.GH6081@sejong
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>
Improve the error message if we can not find given member in the given
structure. Currently perf probe shows a wrong error message as below.
-----
# perf probe getname_flags:65 "result->BOGUS"
result(type:filename) has no member BOGUS.
Failed to find 'result' in this function.
Error: Failed to add events. (-22)
-----
The first message is correct, but the second one is not, since we didn't
fail to find a variable but fails to find the member of given variable.
-----
# perf probe getname_flags:65 "result->BOGUS"
result(type:filename) has no member BOGUS.
Error: Failed to add events. (-22)
-----
With this patch, the error message shows only the first one. And if we
really failed to find given variable, it tells us so.
-----
# perf probe getname_flags:65 "BOGUS"
Failed to find 'BOGUS' in this function.
Error: Failed to add events. (-2)
-----
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
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/20140606071345.6788.23744.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix a segfault bug by asking for variable it doesn't find.
Since the convert_variable() didn't handle error code returned
from convert_variable_location(), it just passed an incomplete
variable field and then a segfault was occurred when formatting
the field.
This fixes that bug by handling success code correctly in
convert_variable(). Other callers of convert_variable_location()
are correctly checking the return code.
This bug was introduced by following commit. But another hidden
erroneous error handling has been there previously (-ENOMEM case).
commit 3d918a12a1
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20140529105232.28251.30447.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
As Namhyung reported(https://lkml.org/lkml/2014/4/1/89),
current perf-probe -L option doesn't handle errors in line-range
searching correctly. It causes a SEGV if an error occured in the
line-range searching.
----
$ perf probe -x ./perf -v -L map__load
Open Debuginfo file: /home/namhyung/project/linux/tools/perf/perf
fname: util/map.c, lineno:153
New line range: 153 to 2147483647
path: (null)
Segmentation fault (core dumped)
----
This is because line_range_inline_cb() ignores errors
from find_line_range_by_line() which means that lr->path is
already freed on the error path in find_line_range_by_line().
As a result, get_real_path() accesses the lr->path and it
causes a NULL pointer exception.
This fixes line_range_inline_cb() to handle the error correctly,
and report it to the caller.
Anyway, this just fixes a possible SEGV bug, Namhyung's patch
is also required.
Reported-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140402054831.19080.27006.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Jiri Olsa <jolsa@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>
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>
At this point, --fentry (mcount function entry) option for gcc fuzzes
the debuginfo variable locations by skipping the mcount instruction
offset (on x86, this is a 5 byte call instruction).
This makes variable searching fail at the entry of functions which
are mcount'ed.
e.g.)
Available variables at vfs_read
@<vfs_read+0>
(No matched variables)
This patch adds additional location search at the function entry point
to solve this issue, which tries to find the earliest address for the
variable location.
Note that this only works with function parameters (formal parameters)
because any local variables should not exist on the function entry
address (those are not initialized yet).
With this patch, perf probe shows correct parameters if possible;
# perf probe --vars vfs_read
Available variables at vfs_read
@<vfs_read+0>
char* buf
loff_t* pos
size_t count
struct file* file
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/20131011071025.15557.13275.stgit@udc4-manage.rcp.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix to find the correct (as much as possible) line information for
listing probes. Without this fix, perf probe --list action will show
incorrect line information as below;
probe:getname_flags (on getname_flags@ksrc/linux-3/fs/namei.c)
probe:getname_flags_1 (on getname:-89@x86/include/asm/current.h)
probe:getname_flags_2 (on user_path_at_empty:-2054@x86/include/asm/current.h)
The minus line number is obviously wrong, and current.h is not related
to the probe point. Deeper investigation discovered that there were 2
issues related to this bug, and minor typos too.
The 1st issue is the rack of considering about nested inlined functions,
which causes the wrong (relative) line number.
The 2nd issue is that the dwarf line info is not correct at those
points. It points 14th line of current.h.
Since it seems that the line info includes somewhat unreliable
information, this fixes perf to try to find correct line information
from both of debuginfo and line info as below.
1) Probe address is the entry of a function instance
In this case, the line is set as the function declared line.
2) Probe address is the entry of an expanded inline function block
In this case, the line is set as the function call-site line.
This means that the line number is relative from the entry line
of caller function (which can be an inlined function if nested)
3) Probe address is inside a function instance or an expanded
inline function block
In this case, perf probe queries the line number from lineinfo
and verify the function declared file is same as the file name
queried from lineinfo.
If the file name is different, it is a failure case. The probe
address is shown as symbol+offset.
4) Probe address is not in the any function instance
This is a failure case, the probe address is shown as
symbol+offset.
With this fix, perf probe -l shows correct probe lines as below;
probe:getname_flags (on getname_flags@ksrc/linux-3/fs/namei.c)
probe:getname_flags_1 (on getname:2@ksrc/linux-3/fs/namei.c)
probe:getname_flags_2 (on user_path_at_empty:4@ksrc/linux-3/fs/namei.c)
Changes at v2:
- Fix typos in the function comments. (Thanks to Namhyung Kim)
- Use die_find_top_inlinefunc instead of die_find_inlinefunc_next.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@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/20130930092144.1693.11058.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>
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>
gcc 4.6 generates a concrete out-of-line instance when there is a
function which is implicitly inlined somewhere but also has its own
instance. The concrete out-of-line instance means that it has an
abstract origin of the function which is referred by not only
inlined-subroutines but also a concrete subprogram.
Since current dwarf_func_inline_instances() can find only instances of
inlined-subroutines, this introduces new die_walk_instances() to find
both of subprogram and inlined-subroutines.
e.g. without this,
Available variables at sched_group_rt_period
@<cpu_rt_period_read_uint+9>
struct task_group* tg
perf probe failed to find actual subprogram instance of
sched_group_rt_period().
With this,
Available variables at sched_group_rt_period
@<cpu_rt_period_read_uint+9>
struct task_group* tg
@<sched_group_rt_period+0>
struct task_group* tg
Now it found the sched_group_rt_period() itself.
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/20110811110311.19900.63997.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix variable searching logic to search one in inner than local scope or
global(CU) scope. In the other words, skip searching in intermediate
scopes.
e.g., in the following code,
int var1;
void inline infunc(int i)
{
i++; <--- [A]
}
void func(void)
{
int var1, var2;
infunc(var2);
}
At [A], "var1" should point the global variable "var1", however, if user
mis-typed as "var2", variable search should be failed. However, current
logic searches variable infunc() scope, global scope, and then func()
scope. Thus, it can find "var2" variable in func() scope. This may not
be what user expects.
So, it would better not search outer scopes except outermost (compile
unit) scope which contains only global variables, when it failed to find
given variable in local scope.
E.g.
Without this:
$ perf probe -V pre_schedule --externs > without.vars
With this:
$ perf probe -V pre_schedule --externs > with.vars
Check the diff:
$ diff without.vars with.vars
88d87
< int cpu
133d131
< long unsigned int* switch_count
These vars are actually in the scope of schedule(), the caller of
pre_schedule().
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/20110811110305.19900.94374.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
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>
