To match the semantics for list.h in the kernel, that are the
interface we use in them.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-mdp1heu9xjjc12zebh91232l@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To match the semantics for list.h in the kernel, that are the
interface we use in them.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0b5i2ki9c3di6706fxpticsb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And do nothing, just like free(), to avoid having to test it in callers,
usually in error paths.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-q42gj3b3znhho9z1mrbo4jce@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add --cache option to cache the probe definitions. This just saves the
result of the dwarf analysis to probe cache.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160615032840.31330.44412.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Uncomment and export synthesize_perf_probe_point() which had once
introduced but has been disabled for a long time. This renews the code
and re-enable it.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160608092949.3116.21958.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add perf_probe_event__copy() to copy perf_probe_event data structure and
sub data structures under given source perf_probe_event.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160608092940.3116.18034.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Check the return value of strbuf APIs in perf-probe
related code, so that it can handle errors in strbuf.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160510054707.6158.69861.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
ppc64le functions have a Global Entry Point (GEP) and a Local Entry
Point (LEP). While placing a probe, we always prefer the LEP since it
catches function calls through both the GEP and the LEP. In order to do
this, we fixup the function entry points during elf symbol table lookup
to point to the LEPs. This works, but breaks 'perf test kallsyms' since
the symbols loaded from the symbol table (pointing to the LEP) do not
match the symbols in kallsyms.
To fix this, we do not adjust all the symbols during symbol table load.
Instead, we note down st_other in a newly introduced arch-specific
member of perf symbol structure, and later use this to adjust the probe
trace point.
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/6be7c2b17e370100c2f79dd444509df7929bdd3e.1460451721.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf is not able to register probe in kernel module when dwarf supprt
is not there(and so it goes for symtab). Perf passes full path of
module where only module name is required which is causing the problem.
This patch fixes this issue.
Before applying patch:
$ dpkg -s libdw-dev
dpkg-query: package 'libdw-dev' is not installed and no information is...
$ sudo ./perf probe -m /linux/samples/kprobes/kprobe_example.ko kprobe_init
Added new event:
probe:kprobe_init (on kprobe_init in /linux/samples/kprobes/kprobe_example.ko)
You can now use it in all perf tools, such as:
perf record -e probe:kprobe_init -aR sleep 1
$ sudo cat /sys/kernel/debug/tracing/kprobe_events
p:probe/kprobe_init /linux/samples/kprobes/kprobe_example.ko:kprobe_init
$ sudo ./perf record -a -e probe:kprobe_init
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.105 MB perf.data ]
$ sudo ./perf script # No output here
After applying patch:
$ sudo ./perf probe -m /linux/samples/kprobes/kprobe_example.ko kprobe_init
Added new event:
probe:kprobe_init (on kprobe_init in kprobe_example)
You can now use it in all perf tools, such as:
perf record -e probe:kprobe_init -aR sleep 1
$ sudo cat /sys/kernel/debug/tracing/kprobe_events
p:probe/kprobe_init kprobe_example:kprobe_init
$ sudo ./perf record -a -e probe:kprobe_init
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.105 MB perf.data (2 samples) ]
$ sudo ./perf script
insmod 13990 [002] 5961.216833: probe:kprobe_init: ...
insmod 13995 [002] 5962.889384: probe:kprobe_init: ...
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1461680741-12517-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf can add a probe on kernel module which has not been loaded yet.
The current implementation finds the module name from path. But if the
filename is different from the actual module name then perf fails to
register a probe while loading module because of mismatch in the names.
For example, samples/kobject/kobject-example.ko is loaded as
kobject_example.
Before applying patch:
$ sudo ./perf probe -m /linux/samples/kobject/kobject-example.ko foo_show
Added new event:
probe:foo_show (on foo_show in kobject-example)
You can now use it in all perf tools, such as:
perf record -e probe:foo_show -aR sleep 1
$ cat /sys/kernel/debug/tracing/kprobe_events
p:probe/foo_show kobject-example:foo_show
$ insmod kobject-example.ko
$ lsmod
Module Size Used by
kobject_example 16384 0
Generate read to /sys/kernel/kobject_example/foo while recording data
with below command
$ sudo ./perf record -e probe:foo_show -a
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.093 MB perf.data ]
$./perf report --stdio -F overhead,comm,dso,sym
Error:
The perf.data.old file has no samples!
After applying patch:
$ sudo ./perf probe -m /linux/samples/kobject/kobject-example.ko foo_show
Added new event:
probe:foo_show (on foo_show in kobject_example)
You can now use it in all perf tools, such as:
perf record -e probe:foo_show -aR sleep 1
$ sudo cat /sys/kernel/debug/tracing/kprobe_events
p:probe/foo_show kobject_example:foo_show
$ insmod kobject-example.ko
$ lsmod
Module Size Used by
kobject_example 16384 0
Generate read to /sys/kernel/kobject_example/foo while recording data
with below command
$ sudo ./perf record -e probe:foo_show -a
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.097 MB perf.data (8 samples) ]
$ sudo ./perf report --stdio -F overhead,comm,dso,sym
...
# Samples: 8 of event 'probe:foo_show'
# Event count (approx.): 8
#
# Overhead Command Shared Object Symbol
# ........ ....... ................. ............
#
100.00% cat [kobject_example] [k] foo_show
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1461680741-12517-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Set kprobe group name as "probe" if it is not given.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426090413.11891.95640.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix a bug to close target elf file in get_text_start_address().
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426064737.1443.44093.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have addch() for chars, add() for fixed size data, and addstr() for
variable length strings, use them.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0ap02fn2xtvpduj2j6b2o1j4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
By extending the syntax of BPF object section names, this patch allows users to
config probing options like what they can do in 'perf probe'.
The error message in 'perf probe' is also updated.
Test result:
For following BPF file test_probe_glob.c:
# cat test_probe_glob.c
__attribute__((section("inlines=no;func=SyS_dup?"), used))
int func(void *ctx)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
#
# ./perf record -e ./test_probe_glob.c ls /
...
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data ]
# ./perf evlist
perf_bpf_probe:func_1
perf_bpf_probe:func
After changing "inlines=no" to "inlines=yes":
# ./perf record -e ./test_probe_glob.c ls /
...
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data ]
# ./perf evlist
perf_bpf_probe:func_3
perf_bpf_probe:func_2
perf_bpf_probe:func_1
perf_bpf_probe:func
Then test 'force':
Use following program:
# cat test_probe_force.c
__attribute__((section("func=sys_write"), used))
int funca(void *ctx)
{
return 1;
}
__attribute__((section("force=yes;func=sys_write"), used))
int funcb(void *ctx)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
#
# perf record -e ./test_probe_force.c usleep 1
Error: event "func" already exists.
Hint: Remove existing event by 'perf probe -d'
or force duplicates by 'perf probe -f'
or set 'force=yes' in BPF source.
event syntax error: './test_probe_force.c'
\___ Probe point exist. Try 'perf probe -d "*"' and set 'force=yes'
(add -v to see detail)
...
Then replace 'force=no' to 'force=yes':
# vim test_probe_force.c
# perf record -e ./test_probe_force.c usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.017 MB perf.data ]
# perf evlist
perf_bpf_probe:func_1
perf_bpf_probe:func
#
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In find_perf_probe_point_from_map(), the 'ret' variable is initialized
with -ENOENT but overwritten by the return code of
kernel_get_symbol_address_by_name(), and after that it is re-initialized
with -ENOENT again.
Setting ret=-ENOENT twice looks a bit redundant. This avoids the
overwriting and just returns -ENOENT if some error happens to simplify
the code.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/n/tip-ufp1zgbktzmttcputozneomd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It is possible that find_perf_probe_point_from_map() fails to find a
symbol but still returns 0 because of an small error when coding:
find_perf_probe_point_from_map() set 'ret' to error code at first, but
also use it to hold return value of kernel_get_symbol_address_by_name().
This patch resets 'ret' to error even kernel_get_symbol_address_by_name()
success, so if !sym, the whole function returns error correctly.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446729565-27592-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Allow probing on kernel modules when 'perf' is built without debuginfo
support.
Currently perf-probe --module requires linking with libdw, but this
doesn't make sense.
E.g.
----
# make NO_DWARF=1
# ./perf probe -m pcspkr pcspkr_event%return
Error: unknown switch `m'
----
With this patch
----
# ./perf probe -m pcspkr pcspkr_event%return
Added new event:
probe:pcspkr_event (on pcspkr_event%return in pcspkr)
You can now use it in all perf tools, such as:
perf record -e probe:pcspkr_event -aR sleep 1
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20151002125832.18617.78721.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf probe --list will get a segfault if the first kprobe event is on a
module and the second or latter one is on the kernel.
e.g.
----
# ./perf probe -q -m pcspkr pcspkr_event
# ./perf probe -q vfs_read
# ./perf probe -l
Segmentation fault (core dumped)
----
This is because the debuginfo_cache fails to handle NULL module name,
which causes segfault on strcmp. (Note that strcmp("something", NULL)
always causes segfault)
To fix this debuginfo_cache__open always translates the NULL module name
to "kernel" (this is correct, because NULL module name means opening the
debuginfo for the kernel)
----
# ./perf probe -l
probe:pcspkr_event (on pcspkr_event@drivers/input/misc/pcspkr.c
in pcspkr)
probe:vfs_read (on vfs_read@ksrc/linux-3/fs/read_write.c)
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150930164135.3733.23993.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf probe always failed to find appropriate line numbers because of
failing to find .text start address offset from debuginfo.
e.g.
----
# ./perf probe -m pcspkr pcspkr_event:5
Added new events:
probe:pcspkr_event (on pcspkr_event:5 in pcspkr)
probe:pcspkr_event_1 (on pcspkr_event:5 in pcspkr)
You can now use it in all perf tools, such as:
perf record -e probe:pcspkr_event_1 -aR sleep 1
# ./perf probe -l
Failed to find debug information for address ffffffffa031f006
Failed to find debug information for address ffffffffa031f016
probe:pcspkr_event (on pcspkr_event+6 in pcspkr)
probe:pcspkr_event_1 (on pcspkr_event+22 in pcspkr)
----
This fixes the above issue as below.
1. Get the relative address of the symbol in .text by using
map->start.
2. Adjust the address by adding the offset of .text section
in the kernel module binary.
With this fix, perf probe -l shows lines correctly.
----
# ./perf probe -l
probe:pcspkr_event (on pcspkr_event:5@drivers/input/misc/pcspkr.c in pcspkr)
probe:pcspkr_event_1 (on pcspkr_event:5@drivers/input/misc/pcspkr.c in pcspkr)
----
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: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150930164132.3733.24643.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix to remove dot suffix (e.g. .const, .isra) from the second or latter
events which has suffix numbers.
Since the previous commit 35a23ff928 ("perf probe: Cut off the gcc
optimization postfixes from function name") didn't care about the suffix
numbered events, therefore we'll have an error when we add additional
events on the same dot suffix functions.
e.g.
----
# ./perf probe -f -a get_sigframe.isra.2.constprop.3 \
-a get_sigframe.isra.2.constprop.3
Failed to write event: Invalid argument
Error: Failed to add events.
----
This fixes above issue as below:
----
# ./perf probe -f -a get_sigframe.isra.2.constprop.3 \
-a get_sigframe.isra.2.constprop.3
Added new events:
probe:get_sigframe (on get_sigframe.isra.2.constprop.3)
probe:get_sigframe_1 (on get_sigframe.isra.2.constprop.3)
You can now use it in all perf tools, such as:
perf record -e probe:get_sigframe_1 -aR sleep 1
----
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150930164130.3733.26573.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
And it is also a step in the direction of killing the separation of data
and text maps in map_groups.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-rrds86kb3wx5wk8v38v56gw8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In places where we were using its open coded equivalent.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-khkdugcdoqy3tkszm3jdxgbe@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have map_groups__find_by_name() to look at the list of modules that
are in place for a given machine, so use it instead of traversing the
machine dso list, which also includes DSOs for userspace.
When merging the user and kernel DSO lists a bug was introduced where
'perf probe' stopped being able to add probes to modules using its short
name:
# perf probe -m usbnet --add usbnet_start_xmit
usbnet_start_xmit is out of .text, skip it.
Error: Failed to add events.
#
With this fix it works again:
# perf probe -m usbnet --add usbnet_start_xmit
Added new event:
probe:usbnet_start_xmit (on usbnet_start_xmit in usbnet)
You can now use it in all perf tools, such as:
perf record -e probe:usbnet_start_xmit -aR sleep 1
#
Reported-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes: 3d39ac5386 ("perf machine: No need to have two DSOs lists")
Link: http://lkml.kernel.org/r/20150924015008.GE1897@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The init/exit_symbols_maps() functions are to setup and cleanup
necessary info for probe events. But they need to be called from out of
the probe code now, so this patch exports them.
However the names are too generic, so change them to have 'probe'. :)
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1441852026-28974-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The cleanup_perf_probe_events() frees all resources related to a perf
probe event. However it only freed resources in trace probe events, not
perf probe events. So call clear_perf_probe_event() too.
Reported-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1441852026-28974-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Switching to the fs.c related filesystem framework.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Raphael Beamonte <raphael.beamonte@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1441180605-24737-14-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Showing actual trace event when deleteing perf events is only needed in
perf probe command. But the add functionality itself can be used by
other places. So move the printing code into the cmd_probe().
The output is not changed.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Showing actual trace event when adding perf events is only needed in
perf probe command. But the add functionality itself can be used by
other places. So move the printing code into the cmd_probe().
Also it combines the output if more than one event is added.
Before:
$ sudo perf probe -a do_fork -a do_exit
Added new event:
probe:do_fork (on do_fork)
You can now use it in all perf tools, such as:
perf record -e probe:do_fork -aR sleep 1
Added new events:
probe:do_exit (on do_exit)
probe:do_exit_1 (on do_exit)
You can now use it in all perf tools, such as:
perf record -e probe:do_exit_1 -aR sleep 1
After:
$ sudo perf probe -a do_fork -a do_exit
Added new events:
probe:do_fork (on do_fork)
probe:do_exit (on do_exit)
probe:do_exit_1 (on do_exit)
You can now use it in all perf tools, such as:
perf record -e probe:do_exit_1 -aR sleep 1
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch drops struct __event_package structure. Instead, it adds a
'struct trace_probe_event' pointer to 'struct perf_probe_event'.
The trace_probe_event information gives further patches a chance to
access actual probe points and actual arguments.
Using them, 'perf probe' can get the whole list of added probes and
print them at once.
Other users like the upcoming bpf_loader will be able to attach one bpf
program to different probing points of an inline function (which has
multiple probing points) and glob functions.
Moreover, by reading the arguments information, bpf code for reading
those arguments can be generated.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-2-git-send-email-namhyung@kernel.org
[namhyung: extract necessary part from the existing patch]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The add_perf_probe_events() does 3 things:
1. convert all perf events to trace events
2. add all trace events to kernel
3. cleanup all trace events
But sometimes we need to do something with the trace events. So split
the funtion into three, so that it can access intermediate trace events
via struct __event_package if needed.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It should be useful to allow 'perf probe' probe at absolute offset of a
target. For example, when (u)probing at a instruction of a shared object
in a embedded system where debuginfo is not avaliable but we know the
offset of that instruction by manually digging.
This patch enables following perf probe command syntax:
# perf probe 0xffffffff811e6615
And
# perf probe /lib/x86_64-linux-gnu/libc-2.19.so 0xeb860
In the above example, we don't need a anchor symbol, so it is possible
to compute absolute addresses using other methods and then use 'perf
probe' to create the probing points.
v1 -> v2:
Drop the leading '+' in cmdline;
Allow uprobing at offset 0x0;
Improve 'perf probe -l' result when uprobe at area without debuginfo.
v2 -> v3:
Split bugfix to a separated patch.
Test result:
# perf probe 0xffffffff8119d175 %ax
# perf probe sys_write %ax
# perf probe /lib64/libc-2.18.so 0x0 %ax
# perf probe /lib64/libc-2.18.so 0x5 %ax
# perf probe /lib64/libc-2.18.so 0xd8e40 %ax
# perf probe /lib64/libc-2.18.so __write %ax
# perf probe /lib64/libc-2.18.so 0xd8e49 %ax
# cat /sys/kernel/debug/tracing/uprobe_events
p:probe_libc/abs_0 /lib64/libc-2.18.so:0x (null) arg1=%ax
p:probe_libc/abs_5 /lib64/libc-2.18.so:0x0000000000000005 arg1=%ax
p:probe_libc/abs_d8e40 /lib64/libc-2.18.so:0x00000000000d8e40 arg1=%ax
p:probe_libc/__write /lib64/libc-2.18.so:0x00000000000d8e40 arg1=%ax
p:probe_libc/abs_d8e49 /lib64/libc-2.18.so:0x00000000000d8e49 arg1=%ax
# cat /sys/kernel/debug/tracing/kprobe_events
p:probe/abs_ffffffff8119d175 0xffffffff8119d175 arg1=%ax
p:probe/sys_write _text+1692016 arg1=%ax
# perf probe -l
Failed to find debug information for address 5
probe:abs_ffffffff8119d175 (on sys_write+5 with arg1)
probe:sys_write (on sys_write with arg1)
probe_libc:__write (on @unix/syscall-template.S:81 in /lib64/libc-2.18.so with arg1)
probe_libc:abs_0 (on 0x0 in /lib64/libc-2.18.so with arg1)
probe_libc:abs_5 (on 0x5 in /lib64/libc-2.18.so with arg1)
probe_libc:abs_d8e40 (on @unix/syscall-template.S:81 in /lib64/libc-2.18.so with arg1)
probe_libc:abs_d8e49 (on __GI___libc_write+9 in /lib64/libc-2.18.so with arg1)
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch fixes a bug that, when offset is provided but function is
lost, parse_perf_probe_point() will give a "" string as function name,
so the checking code at the end of parse_perf_probe_point() become
useless. For example:
# perf probe +0x1234
Failed to find symbol in kernel
Error: Failed to add events.
After this patch:
# perf probe +0x1234
Semantic error :Offset requires an entry function.
Error: Command Parse Error.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-6-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When manually added uprobe point with zero address, 'perf probe -l'
reports error. For example:
# echo p:probe_libc/abs_0 /path/to/lib.bin:0x0 arg1=%ax > \
/sys/kernel/debug/tracing/uprobe_events
# perf probe -l
Error: Failed to show event list.
Probing at 0x0 is possible and useful when lib.bin is not a normal
shared object but is manually mapped. However, in this case kernel
report:
# cat /sys/kernel/debug/tracing/uprobe_events
p:probe_libc/abs_0 /path/to/lib.bin:0x (null) arg1=%ax
This patch supports the above kernel output.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
'perf probe -l' reports error if it is unable find symbol through
address. Here is an example.
# echo 'p:probe_libc/abs_5 /lib64/libc.so.6:0x5' >
/sys/kernel/debug/tracing/uprobe_events
# cat /sys/kernel/debug/tracing/uprobe_events
p:probe_libc/abs_5 /lib64/libc.so.6:0x0000000000000005
# perf probe -l
Error: Failed to show event list
Also, this situation triggers a logical inconsistency in
convert_to_perf_probe_point() that, it returns ENOMEM but actually it
never try strdup().
This patch removes !tp->module && !is_kprobe condition, so it always
uses address to build function name if symbol not found.
Test result:
# perf probe -l
probe_libc:abs_5 (on 0x5 in /lib64/libc.so.6)
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
'perf probe -l' panic if there is a manually inserted probing point with
absolute address. For example:
# echo 'p:probe/abs_ffffffff811e6615 0xffffffff811e6615' > /sys/kernel/debug/tracing/kprobe_events
# perf probe -l
Segmentation fault (core dumped)
This patch fix this problem by considering the situation that
"tp->symbol == NULL" in find_perf_probe_point_from_dwarf() and
find_perf_probe_point_from_map().
After this patch:
# perf probe -l
probe:abs_ffffffff811e6615 (on SyS_write+5@fs/read_write.c)
And when debug info is missing:
# rm -rf ~/.debug
# mv /lib/modules/4.2.0-rc1+/build/vmlinux /lib/modules/4.2.0-rc1+/build/vmlinux.bak
# perf probe -l
probe:abs_ffffffff811e6615 (on sys_write+5)
Signed-off-by: Wang Nan <wangnan0@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: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440509256-193590-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A problem can occur in a statically linked perf when vmlinux can be found:
# perf probe --add sys_epoll_pwait
probe-definition(0): sys_epoll_pwait
symbol:sys_epoll_pwait file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
Looking at the vmlinux_path (7 entries long)
Using /lib/modules/4.2.0-rc1+/build/vmlinux for symbols
Open Debuginfo file: /lib/modules/4.2.0-rc1+/build/vmlinux
Try to find probe point from debuginfo.
Symbol sys_epoll_pwait address found : ffffffff8122bd40
Matched function: SyS_epoll_pwait
Failed to get call frame on 0xffffffff8122bd40
An error occurred in debuginfo analysis (-2).
Error: Failed to add events. Reason: No such file or directory (Code: -2)
The reason is caused by libdw that, if libdw is statically linked, it
can't load libebl_{arch}.so reliable.
In this case it is still possible to get the address from
/proc/kalksyms. However, perf tries that only when libdw returns
-EBADF.
This patch gives it another chance to utilize symbol table, even if
libdw returns an error code other than -EBADF.
After applying this patch:
# perf probe -nv --add sys_epoll_pwait
probe-definition(0): sys_epoll_pwait
symbol:sys_epoll_pwait file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
Looking at the vmlinux_path (7 entries long)
Using /lib/modules/4.2.0-rc1+/build/vmlinux for symbols
Open Debuginfo file: /lib/modules/4.2.0-rc1+/build/vmlinux
Try to find probe point from debuginfo.
Symbol sys_epoll_pwait address found : ffffffff8122bd40
Matched function: SyS_epoll_pwait
Failed to get call frame on 0xffffffff8122bd40
An error occurred in debuginfo analysis (-2).
Trying to use symbols.
Opening /sys/kernel/debug/tracing/kprobe_events write=1
Added new event:
Writing event: p:probe/sys_epoll_pwait _text+2276672
probe:sys_epoll_pwait (on sys_epoll_pwait)
You can now use it in all perf tools, such as:
perf record -e probe:sys_epoll_pwait -aR sleep 1
Although libdw returns an error (Failed to get call frame), perf tries
symbol table and finally gets correct address.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440151770-129878-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Simplify the __add_probe_trace_events() code by taking out the
probe_trace_event__set_name() and updating show_perf_probe_event()
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.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/20150715091400.8915.85501.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that we can pass more info to strlist__new() without having to change
its function signature, just adding entries to the strlist_config struct
with sensible defaults for when those fields are not specified.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-5uaaler4931i0s9sedxjquhq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix failure to probe events on arm, the problem was introduced by commit
5a51fcd1f3 ("perf probe: Skip kernel symbols which is out of .text").
For some architectures, the '_etext' label is not in the .text section
(in the .notes section for arm/arm64). Labels out of the .text section
are not loaded as symbols and we get a zero value when looking up its
addresses, which causes all events to be wrongly skipped.
This patch skips checking the text address range when failing to get the
address of '_etext' and thus fixes the problem.
The problem can be reproduced on arm as follows:
# perf probe --add='generic_perform_write'
generic_perform_write+0 is out of .text, skip it.
Probe point 'generic_perform_write' not found.
Error: Failed to add events.
After this patch:
# perf probe --add='generic_perform_write'
Added new event:
probe:generic_perform_write (on generic_perform_write)
You can now use it in all perf tools, such as:
perf record -e probe:generic_perform_write -aR sleep 1
Signed-off-by: He Kuang <hekuang@huawei.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/1434595750-129791-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Speed up the "perf probe --list" by caching the last used debuginfo.
perf probe --list always open and load debuginfo for each entry of probe
list. This takes very a long time.
E.g. with vfs_* events (total 96 probes)
[root@localhost perf]# time ./perf probe -l &> /dev/null
real 0m25.376s
user 0m24.381s
sys 0m1.012s
To solve this issue, this adds debuginfo_cache to cache the
last used debuginfo on memory.
With this fix, the perf-probe --list significantly improves
its speed.
[root@localhost perf]# time ./perf probe -l &> /dev/null
real 0m0.161s
user 0m0.136s
sys 0m0.025s
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/20150617145854.19715.15314.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the last part of converted events are blacklisted or out-of-text,
those are skipped and perf probe doesn't show usage examples. This
fixes it to show the example even if the last part of event list is
skipped.
E.g. without this patch, events are added, but suddenly end:
# perf probe vfs_*
vfs_caches_init_early is out of .text, skip it.
vfs_caches_init is out of .text, skip it.
Added new events:
probe:vfs_fallocate (on vfs_*)
probe:vfs_open (on vfs_*)
...
probe:vfs_dentry_acceptable (on vfs_*)
probe:vfs_load_quota_inode (on vfs_*)
#
With this fix:
# perf probe vfs_*
vfs_caches_init_early is out of .text, skip it.
vfs_caches_init is out of .text, skip it.
Added new events:
probe:vfs_fallocate (on vfs_*)
...
probe:vfs_load_quota_inode (on vfs_*)
You can now use it in all perf tools, such as:
perf record -e probe:vfs_load_quota_inode -aR sleep 1
Note that this can be reproduced ONLY IF the vfs_caches_init* is the
last part of matched symbol list. I've checked this happens on
"3.19.0-generic #18-Ubuntu" kernel binary.
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/20150616115057.19906.5502.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix perf probe to return an error if no probe is added due to the given
probe point being on the blacklist.
To fix this problem, this moves the blacklist checking to right after
finding symbols/probe-points and marks them as skipped.
If all the symbols are skipped, "perf probe" returns an error as it
fails to find the corresponding probe address.
E.g. currently if a blacklisted probe is given:
# perf probe do_trap && echo 'succeed'
Added new event:
Warning: Skipped probing on blacklisted function: sync_regs
succeed
No! It must fail! With this patch, it correctly fails:
# perf probe do_trap && echo 'succeed'
do_trap is blacklisted function, skip it.
Probe point 'do_trap' not found.
Error: Failed to add events.
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/20150616115055.19906.31359.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since commit 5e17b28f1e ("perf probe: Add --quiet option to
suppress output result message") have replaced printf with pr_info,
perf probe -l outputs its result in stderr. However, that is not
what the commit expected.
E.g.:
# perf probe -l > /dev/null
probe:vfs_read (on vfs_read@ksrc/linux-3/fs/read_write.c)
With this fix:
# perf probe -l > list
# cat list
probe:vfs_read (on vfs_read@ksrc/linux-3/fs/read_write.c)
Of course, --quiet(-q) still works on --add/--del.
# perf probe -q vfs_write
# perf probe -l
probe:vfs_read (on vfs_read@ksrc/linux-3/fs/read_write.c)
probe:vfs_write (on vfs_write@ksrc/linux-3/fs/read_write.c)
-----
Reported-by: Naohiro Aota <naota@elisp.net>
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/20150613013116.24402.2923.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cut off the postfixes which gcc added for optimized routines from the
event name automatically generated from symbol name, since *probe-events
doesn't accept it. Those symbols will be used if we don't use debuginfo
to find target functions.
E.g. without this fix;
-----
# perf probe -va alloc_buf.isra.23
probe-definition(0): alloc_buf.isra.23
symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
[...]
Opening /sys/kernel/debug/tracing/kprobe_events write=1
Added new event:
Writing event: p:probe/alloc_buf.isra.23 _text+4869328
Failed to write event: Invalid argument
Error: Failed to add events. Reason: Invalid argument (Code: -22)
-----
With this fix;
-----
perf probe -va alloc_buf.isra.23
probe-definition(0): alloc_buf.isra.23
symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
[...]
Opening /sys/kernel/debug/tracing/kprobe_events write=1
Added new event:
Writing event: p:probe/alloc_buf _text+4869328
probe:alloc_buf (on alloc_buf.isra.23)
You can now use it in all perf tools, such as:
perf record -e probe:alloc_buf -aR sleep 1
-----
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/20150612050820.20548.41625.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Calling the function 'machine__new_module' implies a new 'module' will
be allocated, when in fact what is returned is a 'struct map' instance,
that not necessarily will be instantiated, as if one already exists with
the given module name, it will be returned instead.
So be consistent with other "find and if not there, create" like
functions, like machine__findnew_thread, machine__findnew_dso, etc, and
rename it to machine__findnew_module_map(), that in turn will call
machine__findnew_module_dso().
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-acv830vd3hwww2ih5vjtbmu3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 4c85935122 ("perf probe: Support
glob wildcards for function name") introduces segfault problems when
debuginfo is not available:
# perf probe 'sys_w*'
Added new events:
Segmentation fault
The first problem resides in find_probe_trace_events_from_map(). In
that function, find_probe_functions() is called to match each symbol
against glob to find the number of matching functions, but still use
map__for_each_symbol_by_name() to find 'struct symbol' for matching
functions. Unfortunately, map__for_each_symbol_by_name() does
exact matching by searching in an rbtree.
It doesn't know glob matching, and not easy for it to support it because
it use rbtree based binary search, but we are unable to ensure all names
matched by the glob (any glob passed by user) reside in one subtree.
This patch drops map__for_each_symbol_by_name(). Since there is no
rbtree again, re-matching all symbols costs a lot. This patch avoid it
by saving all matching results into an array (syms).
The second problem is the lost of tp->realname. In
__add_probe_trace_events(), if pev->point.function is glob, the event
name should be set to tev->point.realname. This patch ensures its
existence by strdup sym->name instead of leaving a NULL pointer there.
After this patch:
# perf probe 'sys_w*'
Added new events:
probe:sys_waitid (on sys_w*)
probe:sys_wait4 (on sys_w*)
probe:sys_waitpid (on sys_w*)
probe:sys_write (on sys_w*)
probe:sys_writev (on sys_w*)
You can now use it in all perf tools, such as:
perf record -e probe:sys_writev -aR sleep 1
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1432892747-232506-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
