Currently, perf probe considers patterns including a '.' to be a file.
However, this causes problems on powerpc ABIv1 where all functions have
a leading '.':
$ perf probe -F | grep schedule_timeout_interruptible
.schedule_timeout_interruptible
$ perf probe .schedule_timeout_interruptible
Semantic error :File always requires line number or lazy pattern.
Error: Command Parse Error.
Fix this:
- by checking the probe pattern in more detail, and
- skipping leading dot if one exists when creating/deleting events.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/db680f7cb11c4452b632f908e67151f3aa0f4602.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
On powerpc ABIv2, if no debug-info is found and we use kallsyms, we need
to fixup the function entry to point to the local entry point. Use
offset of 8 since current toolchains always generate 2 instructions (8
bytes).
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/92253021e77a104b23b615c8c23bf9501dfe60bf.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use symbol table lookups by default if DWARF is not necessary, since
powerpc ABIv2 encodes local entry points in the symbol table and the
function entry address in DWARF may not be appropriate for kprobes, as
described here:
https://sourceware.org/bugzilla/show_bug.cgi?id=17638
"The DWARF address ranges deliberately include the *whole* function,
both global and local entry points."
...
"If you want to set probes on a local entry point, you should look up
the symbol in the main symbol table (not DWARF), and check the st_other
bits; they will indicate whether the function has a local entry point,
and what its offset from the global entry point is. Note that GDB does
the same when setting a breakpoint on a function entry."
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/88a10e22f4aaba2aef812824ca4b10d7beeea012.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix perf-probe --del option to delete all matched probes in both
of kprobes and uprobes at once.
When we have 2 or more events on different binaries as below,
----
# ./perf probe -l
probe:vfs_read (on vfs_read@ksrc/linux-3/fs/read_write.c)
probe_libc:malloc (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17
----
Trying to remove all event with '*' just removes kprobe events at first.
----
# ./perf probe -d \*
Removed event: probe:vfs_read
----
And in 2nd try, it removes all uprobe events.
----
# ./perf probe -d \*
Removed event: probe_libc:malloc
----
This fixes to remove all event at once as below.
----
# ./perf probe -d \*
Removed event: probe:vfs_read
Removed event: probe_libc:malloc
----
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
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/20150423134614.26128.18106.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>
When perf probe searched in a debuginfo file and failed, it tried with
an alternative, in function get_alternative_probe_event():
memcpy(tmp, &pev->point, sizeof(*tmp));
memset(&pev->point, 0, sizeof(pev->point));
In this case, it drops the retprobe flag and forgets to set it back in
find_alternative_probe_point(), so the problem occurs.
Can be reproduced as following:
$ perf probe -v -k vmlinux --add='sys_write%return'
...
Added new event:
Writing event: p:probe/sys_write _stext+1584952
probe:sys_write (on sys_write%return)
$ cat /sys/kernel/debug/tracing/kprobe_events
p:probe/sys_write _stext+1584952
After this patch:
$ perf probe -v -k vmlinux --add='sys_write%return'
Added new event:
Writing event: r:probe/sys_write SyS_write+0
probe:sys_write (on sys_write%return)
$ cat /sys/kernel/debug/tracing/kprobe_events
r:probe/sys_write SyS_write
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/1428925290-5623-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Support multiple probes on different binaries with just
one command.
In the result, this example sets up the probes on icmp_rcv in
kernel, on main and set_target in perf, and on pcspkr_event
in pcspker.ko driver.
-----
# perf probe -a icmp_rcv -x ./perf -a main -a set_target \
-m /lib/modules/4.0.0-rc5+/kernel/drivers/input/misc/pcspkr.ko \
-a pcspkr_event
Added new event:
probe:icmp_rcv (on icmp_rcv)
You can now use it in all perf tools, such as:
perf record -e probe:icmp_rcv -aR sleep 1
Added new event:
probe_perf:main (on main in /home/mhiramat/ksrc/linux-3/tools/perf/perf)
You can now use it in all perf tools, such as:
perf record -e probe_perf:main -aR sleep 1
Added new event:
probe_perf:set_target (on set_target in /home/mhiramat/ksrc/linux-3/tools/perf/perf)
You can now use it in all perf tools, such as:
perf record -e probe_perf:set_target -aR sleep 1
Added new event:
probe:pcspkr_event (on pcspkr_event in pcspkr)
You can now use it in all perf tools, such as:
perf record -e probe:pcspkr_event -aR sleep 1
-----
Reported-by: Arnaldo Carvalho de Melo <acme@infradead.org>
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/20150401102539.17137.46454.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 9b118acae3 ("perf probe: Fix to
handle aliased symbols in glibc") uses an absolute format '%lx' to
print u64 argument, which causes compiling error on ARM 32.
This patch replaces it with PRIx64.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1428459274-138470-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch add checks in places where map__kmap is used to get kmaps
from struct kmap.
Error messages are added at map__kmap to warn invalid accessing of kmap
(for the case of !map->dso->kernel, kmap(map) does not exists at all).
Also, introduces map__kmaps() to warn uninitialized kmaps.
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1428394966-131044-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix to get correctly unmapped symbol address on kernel. This allows us
to probe on syscall symbols which are aliases of SyS_ functions with
using debuginfo.
Without this fix:
----
# ./perf probe -a sys_write
Failed to find debug information for address 3b0100
Probe point 'sys_write' not found.
Error: Failed to add events.
----
The address 0x3b0100 is a mapped address, and not usable
in debuginfo.
With this fix:
----
# ./perf probe -a sys_write
Added new event:
probe:sys_write (on sys_write)
You can now use it in all perf tools, such as:
perf record -e probe:sys_write -aR sleep 1
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150322114022.32639.19096.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf tries to find probe function addresses from map when debuginfo
could not be found.
To the first added function, the value of ref_reloc_sym was set in
maps__set_kallsyms_ref_reloc_sym() and can be obtained from
host_machine->kmaps->maps. After that, new maps are added to
host_machine->kmaps->maps in dso__load_kcore(), all these new added maps
do not have a valid ref_reloc_sym.
When adding a second function, get_target_map() may get a map without
valid ref_reloc_sym, and raise the error "Relocated base symbol is not
found".
Fix this by using kernel_get_ref_reloc_sym() to get ref_reloc_sym.
This problem can be reproduced as following:
$ perf probe --add='sys_write' --add='sys_open'
Relocated base symbol is not found!
Error: Failed to add events.
After this patch:
$ perf probe --add='sys_write' --add='sys_open'
Added new event:
probe:sys_write (on sys_write)
You can now use it in all perf tools, such as:
perf record -e probe:sys_write -aR sleep 1
Added new event:
probe:sys_open (on sys_open)
You can now use it in all perf tools, such as:
perf record -e probe:sys_open -aR sleep 1
Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-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/1426816616-2394-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf fails to build with gcc "(GCC) 4.4.7 20120313 (Red Hat
4.4.7-4.0.9)" (a.k.a., RHEL6 / CentOS 6 / OL 6):
cc1: warnings being treated as errors
util/probe-event.c: In function ‘get_alternative_line_range’:
util/probe-event.c:359: error: missing initializer
util/probe-event.c:359: error: (near initialization for ‘pp.file’)
util/probe-event.c:359: error: missing initializer
util/probe-event.c:359: error: (near initialization for ‘result.function’)
Fix by bringing in initializers to declaration.
Signed-off-by: David Ahern <david.ahern@oracle.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/1426084580-60780-1-git-send-email-david.ahern@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A double free occurred when get source file path failed. If lr->path
failed to assign a new value, it will be freed as the old path and then
be freed again during line_range__clear(), and causes this:
$ perf probe -L do_execve -k vmlinux
*** Error in `/usr/bin/perf': double free or corruption (fasttop):
0x0000000000a9ac50 ***
======= Backtrace: =========
../lib64/libc.so.6(+0x6eeef)[0x7ffff5e44eef]
../lib64/libc.so.6(+0x78cae)[0x7ffff5e4ecae]
../lib64/libc.so.6(+0x79987)[0x7ffff5e4f987]
../bin/perf[0x4ab41f]
...
This patch fix this problem.
Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1425463302-1687-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It currently prevents adding probes in weak symbols. But there're cases
that given name is an only weak symbol so that we cannot add probe.
$ perf probe -x /usr/lib/libc.so.6 -a calloc
Failed to find symbol calloc in /usr/lib/libc-2.21.so
Error: Failed to add events.
$ nm /usr/lib/libc.so.6 | grep calloc
000000000007b1f0 t __calloc
000000000007b1f0 T __libc_calloc
000000000007b1f0 W calloc
This change will result in duplicate probes when strong and weak symbols
co-exist in a binary. But I think it's not a big problem since probes
at the weak symbol will never be hit anyway.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073129.6904.41078.stgit@localhost.localdomain
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When perf probe tries to add a probe in a binary using symbol name, it
sometimes failed since some symbols were discard during loading dso.
When it resolves an address to symbol, it'd be better to have just one
symbol at given address. But for finding address from symbol, it'd be
better to keep all names (including aliases).
So allow tools to state that they want to allow aliases via
symbol_conf.allow_aliases.
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: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073127.6904.3232.stgit@localhost.localdomain
[ Original patch passwd allow_alias to many functions, use symbol_conf.allow_aliases instead ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This reverts commit 906451b98b ("perf probe: Fix to fall back to find probe point in symbols").
Since 'perf probe' now retries with the address of given symbol searched from
map before this path, this fall back routine isn't needed anymore.
Signed-off-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: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073124.6904.1751.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix perf probe --line to handle aliased symbols correctly in glibc.
This makes line_range search failing back to address-based alternative
search as same as --add and --vars.
Without this patch;
-----
# ./perf probe -x /usr/lib64/libc-2.17.so -L malloc
Specified source line is not found.
Error: Failed to show lines.
-----
With this patch;
-----
# ./perf probe -x /usr/lib64/libc-2.17.so -L malloc
<__libc_malloc@/usr/src/debug/glibc-2.17-c758a686/malloc/malloc.c:0>
0 __libc_malloc(size_t bytes)
1 {
mstate ar_ptr;
void *victim;
__malloc_ptr_t (*hook) (size_t, const __malloc_ptr_t)
6 = force_reg (__malloc_hook);
7 if (__builtin_expect (hook != NULL, 0))
8 return (*hook)(bytes, RETURN_ADDRESS (0));
10 arena_lookup(ar_ptr);
12 arena_lock(ar_ptr, bytes);
-----
Note that this actually shows __libc_malloc, since it is the real
instance of malloc. User can use both __libc_malloc and malloc for
--line.
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: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073122.6904.18540.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix perf probe to handle aliased symbols correctly in glibc. In the
glibc, several symbols are defined as an alias of __libc_XXX, e.g.
malloc is an alias of __libc_malloc.
In such cases, dwarf has no subroutine instances of the alias functions
(e.g. no "malloc" instance), but the map has that symbol and its
address.
Thus, if we search the alieased symbol in debuginfo, we always fail to
find it, but it is in the map.
To solve this problem, this fails back to address-based alternative
search, which searches the symbol in the map, translates its address to
alternative (correct) function name by using debuginfo, and retry to
find the alternative function point from debuginfo.
This adds fail-back process to --vars, --lines and --add options. So,
now you can use those on malloc@libc :)
Without this patch;
-----
# ./perf probe -x /usr/lib64/libc-2.17.so -V malloc
Failed to find the address of malloc
Error: Failed to show vars.
# ./perf probe -x /usr/lib64/libc-2.17.so -a "malloc bytes"
Probe point 'malloc' not found in debuginfo.
Error: Failed to add events.
-----
With this patch;
-----
# ./perf probe -x /usr/lib64/libc-2.17.so -V malloc
Available variables at malloc
@<__libc_malloc+0>
size_t bytes
# ./perf probe -x /usr/lib64/libc-2.17.so -a "malloc bytes"
Added new event:
probe_libc:malloc (on malloc in /usr/lib64/libc-2.17.so with bytes)
You can now use it in all perf tools, such as:
perf record -e probe_libc:malloc -aR sleep 1
-----
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
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/20150306073120.6904.13779.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Warn if given uprobe event accesses memory on older kernel.
Until 3.14, uprobe event only supports accessing registers so this warns
to upgrade kernel if uprobe-event returns -EINVAL and an argument of the
event accesses memory ($stack, @+offset, and +|-offs() symtax).
With this patch (on 3.10.0-123.13.2.el7.x86_64);
-----
# ./perf probe -x ./perf warn_uprobe_event_compat stack=-0\(%sp\)
Added new event:
Failed to write event: Invalid argument
Please upgrade your kernel to at least 3.14 to have access to feature -0(%sp)
Error: Failed to add events.
-----
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20150228025329.32106.70581.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The minus operator has higher precedence than ?: Add parentheses around
?: fix this.
Before this patch:
$ echo 'p:myprobe do_sys_open' > /sys/kernel/debug/tracing/kprobe_events
$ perf probe -l -k ../vmlinux
kprobes:myprobe (on do_sys_open)
After this patch:
$ echo 'p:myprobe do_sys_open' > /sys/kernel/debug/tracing/kprobe_events
$ perf probe -l -k ../vmlinux
kprobes:myprobe (on do_sys_open@linux.git/fs/open.c)
Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1425034373-14511-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We could end up returning 0 (Ok) with a NULL raw_path. Fix it.
Acked-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>
Link: http://lkml.kernel.org/n/tip-l0kcbcg5f4nnzqt01cv42vec@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix get_real_path to free allocated memory when comp_dir is used for
complementing path and getting an error.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.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/20150226082504.28125.74506.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Recent linux kernel provides a blacklist of the functions which can not
be probed. perf probe can now check this blacklist before setting new
events and indicate better error message for users.
Without this patch,
----
# perf probe --add vmalloc_fault
Added new event:
Failed to write event: Invalid argument
Error: Failed to add events.
----
With this patch
----
# perf probe --add vmalloc_fault
Added new event:
Warning: Skipped probing on blacklisted function: vmalloc_fault
----
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150219143113.14434.5387.stgit@localhost.localdomain
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As tracefs may be mounted instead of debugfs to get to the event
directories, have perf know about tracefs, and use that file system over
debugfs if it is present.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20150202193553.340946602@goodmis.org
[ Fixed up error messages about tracefs pointed out by Namhyung ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
