Propagate error info from tp_format via ERR_PTR to get it all the way
down to the parse-event.c tracepoint adding routines. Following
functions now return pointer with encoded error:
- tp_format
- trace_event__tp_format
- perf_evsel__newtp_idx
- perf_evsel__newtp
This affects several other places in perf, that cannot use pointer check
anymore, but must utilize the err.h interface, when getting error
information from above functions list.
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>
Link: http://lkml.kernel.org/r/1441615087-13886-5-git-send-email-jolsa@kernel.org
[ Add two missing ERR_PTR() and one IS_ERR() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Without this patch, it is cumbersome to read the trace output but
ignoring the normal, potentially verbose, output of the debuggee. One
common example is doing something like the following:
perf trace -s find /tmp > /dev/null
Without this patch, the trace summary will be lost. Now, it will still
be printed at the end. This behavior is also applied by strace.
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/n/tip-tqnks6y2cnvm5f9g2dsfr7zl@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To work like strace and dereference syscall pointer args we need to
insert probes (or tracepoints) right after we copy those bytes from
userspace.
Since we're formatting the syscall args at raw_syscalls:sys_enter time,
we need to have a formatter that just stores the position where, later,
when we get the probe:vfs_getname, we can insert the pointer contents.
Now, if a probe:vfs_getname with this format is in place:
# perf probe -l
probe:vfs_getname (on getname_flags:72@/home/git/linux/fs/namei.c with pathname)
That was, in this case, put in place with:
# perf probe 'vfs_getname=getname_flags:72 pathname=filename:string'
Added new event:
probe:vfs_getname (on getname_flags:72 with pathname=filename:string)
You can now use it in all perf tools, such as:
perf record -e probe:vfs_getname -aR sleep 1
#
Then 'perf trace' will notice that and do the pointer -> contents
expansion:
# trace -e open touch /tmp/bla
0.165 (0.010 ms): touch/17752 open(filename: /etc/ld.so.cache, flags: CLOEXEC) = 3
0.195 (0.011 ms): touch/17752 open(filename: /lib64/libc.so.6, flags: CLOEXEC) = 3
0.512 (0.012 ms): touch/17752 open(filename: /usr/lib/locale/locale-archive, flags: CLOEXEC) = 3
0.582 (0.012 ms): touch/17752 open(filename: /tmp/bla, flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: 438) = 3
#
Roughly equivalent to strace's output:
# strace -rT -e open touch /tmp/bla
0.000000 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3 <0.000039>
0.000317 open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3 <0.000102>
0.001461 open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3 <0.000072>
0.000405 open("/tmp/bla", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = 3 <0.000055>
0.000641 +++ exited with 0 +++
#
Now we need to either look for at all syscalls that are marked as
pointers and have some well known names ("filename", "pathname", etc)
and set the arg formatter to the one used for the "open" syscall in this
patch.
This implementation works for syscalls with just a string being copied
from userspace, for matching syscalls with more than one string being
copied via the same probe/trace point (vfs_getname) we need to extend
the vfs_getname probe spec to include the pointer too, but there are
some problems with that in 'perf probe' or the kernel kprobes code, need
to investigate before considering supporting multiple strings per
syscall.
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: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-xvuwx6nuj8cf389kf9s2ue2s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The python binding still doesn't provide symbol resolving facilities,
but the recent addition of the trace_event__register_resolver() function
made it add as a dependency the machine__resolve_kernel_addr() method,
that in turn drags all the symbol resolving code.
The problem:
[root@zoo ~]# perf test -v python
17: Try 'import perf' in python, checking link problems :
--- start ---
test child forked, pid 6853
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: /tmp/build/perf/python/perf.so: undefined symbol: machine__resolve_kernel_addr
test child finished with -1
---- end ----
Try 'import perf' in python, checking link problems: FAILED!
[root@zoo ~]#
Fix it by requiring this function to receive the resolver as a
parameter, just like pevent_register_function_resolver(), i.e. do
not explicitely refer to an object file not included in
tools/perf/util/python-ext-sources.
[root@zoo ~]# perf test python
17: Try 'import perf' in python, checking link problems : Ok
[root@zoo ~]#
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: c3168b0db9 ("perf symbols: Provide libtraceevent callback to resolve kernel symbols")
Link: http://lkml.kernel.org/n/tip-vxlhh95v2em9zdbgj3jm7xi5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
So that beautifiers wanting to resolve kernel function addresses to
names can do its work, now, for instance, the 'timer' tracepoints
beautifiers works with 'perf trace', see the "function=tick..." part:
# perf trace --event timer:hrtimer_start
<SNIP>
0.000 timer:hrtimer_start:hrtimer=0xffff88026f3101c0 function=tick_sched_timer/0x0 expires=52098339000000 softexpires=52098339000000)
0.003 timer:hrtimer_start:hrtimer=0xffff88026f3101c0 function=tick_sched_timer/0x0 expires=52098339000000 softexpires=52098339000000)
<SNIP>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-n4i0hxpbl1tnleiqkok47fw2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We use raw_syscalls:sys_{enter,exit} events to show the syscalls, but were
using a rather lazy/inneficient way to implement our 'strace -e' equivalent:
filter out after reading the events in the ring buffer.
Deflect more work to the kernel by appending a filter expression for that,
that, together with the pid list, that is always present, if only to filter the
tracer itself, reduces pressure on the ring buffer and otherwise use
infrastructure already in place in the kernel to do early filtering.
If we use it with -v we can see the filter passed to the kernel,
for instance, for this contrieved case:
# trace -v -e \!open,close,write,poll,recvfrom,select,recvmsg,writev,sendmsg,read,futex,epoll_wait,ioctl,eventfd --filter-pids 2189,2566,1398,2692,4475,4532
<SNIP>
(common_pid != 2514 && common_pid != 1398 && common_pid != 2189 && common_pid != 2566 && common_pid != 2692 && common_pid != 4475 && common_pid != 4532) && (id != 3 && id != 232 && id != 284 && id != 202 && id != 16 && id != 2 && id != 7 && id != 0 && id != 45 && id != 47 && id != 23 && id != 46 && id != 1 && id != 20)
0.011 (0.011 ms): caribou/2295 eventfd2(flags: CLOEXEC|NONBLOCK) = 18
16.946 (0.019 ms): caribou/2295 eventfd2(flags: CLOEXEC|NONBLOCK) = 18
38.598 (0.167 ms): chronyd/794 socket(family: INET, type: DGRAM ) = 4
38.603 (0.002 ms): chronyd/794 fcntl(fd: 4<socket:[239307]>, cmd: GETFD) = 0
38.605 (0.001 ms): chronyd/794 fcntl(fd: 4<socket:[239307]>, cmd: SETFD, arg: 1) = 0
^C
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.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-ti2tg18atproqpguc2moinp6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Instead of calling perf_evsel__apply_filter straight away, so that
we can, in the next patches, expand the filter with more conditions
before actually calling the ioctl to pass the end result filter to
the kernel.
Now we need to call perf_evlist__apply_filters() after the filter
is completely setup, i.e. do the ioctl calls.
The perf_evlist__apply_filters() method was already in place, because
that is the model for the other tools that receives filters in the
command line: go on setting then in the evsel->filter and only at
the end, after parsing the whole command line, apply them.
We get, as a bonus, a more expressive message that states which
event, if any, failed to have the filter applied to, with an
error message stating what happened.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.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-f429pgz75ryz7tpe6v74etre@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>